JP2002029174A - Mold for printing blanket - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide molds for a printing blanket, in which the labor and cost for manufacturing is reduced and, at the same time, their handleability at use is improved and, under the condition that the thickness of the printing blanket is prevented from varying widely in regions, in which the designed thicknesses are equal to one another in one and the same printing blanket, or among the same position of a plurality of printing blankets different from one another, the predetermined shape and thickness distribution in dimensions at the arbitrary position of the blanket can be formed by lessening the thicknesses of a pair of the molds. SOLUTION: Under the condition that the outer surface 11 side of one mold 1 between a pair of flat plate-like molds 1 and 2 corresponding to the ink carrying surface and the rear surface of the printing blanket is reinforced by H-steels 3, etc., as reinforcing member, the mold 1 is deformed by spacers S, etc., inserted between the H-steel 3 and an outer surface 11, resulting in forming a convex surface (a three-dimensional surface) having the predetermined dimensions and shape for forming a predetermined thickness distribution on a shaping surface 40 on the inner surface 10 side in a mold M for molding the printing blanket.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a printing blanket used for precision printing, for example.
It relates to a new molding die.

[0002]

2. Description of the Related Art Fine stripe patterns and mask patterns are printed on a substrate such as glass with high density and high precision.
For example, in the field of electronic devices, such as when manufacturing a liquid crystal color filter for a liquid crystal display element, precision printing by the offset printing method has recently been receiving attention. In the offset printing method, the ink image formed on the original plate is printed on the surface of a printing blanket made of an elastic material such as rubber (ink carrying surface).
Then, printing is performed by transferring from the ink carrying surface to the surface of a printing target such as a substrate.

Therefore, as the printing becomes more precise, it is required that the finishing accuracy of the surface of the ink carrying surface of the printing blanket be higher in order to improve the printing accuracy. In addition, the contact pressure of the printing blanket with the original and the object to be printed, that is, the printing pressure, is also a factor that affects the printing accuracy. In order to improve the printing accuracy, the printing pressure is required to be as uniform as possible. . In order to achieve this, irregular thickness variation in the same design blanket in the same design thickness is small, and thickness variation between the same positions of a plurality of different printing blankets is also reduced. It needs to be small.

For example, in a printing blanket for printing a liquid crystal color filter, a thickness variation within a region having an equal design thickness is required to be within 5/100 mm (= 50 μm). In addition, the type of elastic material that forms the printing blanket is also important for improving printing accuracy, and in particular, has less temperature dependence such as dimensional accuracy and compression characteristics than other materials. Silicone rubbers having various properties such as excellent resistance to a solvent to be used and no significant dimensional change due to swelling are preferably used.

A method for producing a printing blanket for precision printing using the above silicone rubber is described in the following 2
Law is conceivable.・ A pair of dies corresponding to the ink carrying surface of the printing blanket and the back surface of the ink carrying surface and back to back are arranged with an interval corresponding to the thickness of the printing blanket, and are placed in a gap formed between the two dies. A room-temperature-curable or heat-curable liquid silicone rubber is injected and cured. Heating the entire printing blanket while compressing it to the thickness of the printing blanket with a thermosetting silicone rubber sandwiched between a pair of molds corresponding to the ink carrying surface of the printing blanket and the back surface of this ink carrying surface and back to back. And cure.

[0006] Japanese Patent No. 2589635 discloses that in order to manufacture a printing blanket for precision printing by these methods, one of a pair of dies corresponding to the ink carrying surface of the printing blanket and the other of the dies. A molding die is described in which a flat shaping member having a shaping surface for shaping the ink carrying surface is formed on an inner surface facing the metal mold. According to the above molding die, by using a plate material whose shaping surface is mirror-finished, such as a glass plate or a polished metal plate, as a shaping member, the finishing accuracy of the ink carrying surface is improved. High printing blankets can be formed. In addition, when the molding surface is damaged, the molding die can be reused by simply replacing the molding member without the need for re-polishing, which is advantageous in terms of maintenance and cost. is there.

[0007]

However, since an elastic material such as silicone rubber generally expands in volume due to a curing reaction, the pressure of the expansion may cause the mold to be distorted or the space between the molds to increase. Therefore, the thickness of the printing blanket may vary irregularly. For more information,
Irregular thickness variations may occur in areas of equal design thickness within one and the same printing blanket, or irregularities may occur between identical locations on a plurality of different printing blankets.

[0008] As a result, there is a possibility that the printing accuracy is reduced due to the variation of the printing pressure. For example, according to studies by the inventors, when a silicone rubber is cured, a high pressure of about 1 to 10 kg / cm ² is applied to a mold. Therefore, for example, when the design thickness is 0.8
As a pair of molds for forming a flat printing blanket of 5 mm having the same thickness, a pair of dies having a thickness of 100 mm (about 117 to 118 of the thickness of the printing blanket to be formed).
In the case where a stainless steel plate having a length of about 1 m in both length and width directions is used, there is a possibility that the central portion may swell up to several hundred μm at the time of molding.

Thereafter, although the swelling gradually disappears with the progress of the curing reaction and the decrease in temperature after the molding, the completed printing blanket swells irregularly by about 100 to 200 μm at the center from the periphery. However, the thickness is not constant. Therefore, conventionally, the thickness of a pair of molds constituting a molding die is set to be remarkably large, for example, 250 times or more the thickness of a printing blanket to be molded, so as to resist the pressure of expansion. It takes a great deal of time to manufacture a large mold, and an increase in the cost of manufacturing the mold also poses a problem.

In particular, the inner surface of one mold for detachably attaching the shaping member, corresponding to the ink carrying surface of the printing blanket, and the other mold corresponding to the back surface, which is back to back with the ink carrying surface. It becomes more difficult to make the inner surface side a flat surface without distortion by cutting or polishing, etc., as the thickness of the mold increases. This is considered to be due to an increase in distortion of the mold), and in combination with an increase in the weight of the mold and poor handling during processing, it takes a great deal of time to produce a mold having a large thickness.

[0011] In addition, as described above, the time required for processing is combined with the fact that a thick and uniform metal material requires a high material cost, so that the cost for manufacturing a mold also increases. In addition, as described above, the mold having a large thickness also poses a problem of poor handling at the time of use due to an increase in weight. In addition, for example, in order to match the mounting state when the molded printing blanket is mounted on a printing press, or to cope with a bias or the like of a printing target that performs printing using the molded printing blanket, the printing is performed. There is a case where a predetermined distribution is given to the thickness of the blanket, in which case, a predetermined dimension, a predetermined size, at a predetermined position of an ink carrying surface of the printing blanket or a shaping surface corresponding to the back surface.
Forming a three-dimensional surface (concave surface, convex surface, etc.) having a shape is performed.

Conventionally, however, a process for forming such a three-dimensional surface must be added to the process of forming a shaped surface.
In particular, in the case of a mold having a large thickness as described above, there is a problem that the cost for manufacturing the mold further increases. Also, the manufactured mold can be used only to form a printing blanket having a thickness distribution of only one type corresponding to the three-dimensional surface formed on the imprinting surface, and has a different thickness distribution from it. In order to form a printing blanket, there is also a problem that a new mold having a three-dimensional surface having a different size and shape at another position on the shaping surface must be manufactured.

An object of the present invention is to reduce the labor and cost required for manufacturing since the thickness of the pair of molds does not need to be significantly increased as in the past, and is excellent in handleability during use. In addition, the thickness of the formed printing blanket can be prevented from being irregularly varied in an area having the same design thickness within one and the same printing blanket, or between the same positions of a plurality of different printing blankets. An object of the present invention is to provide a molding die in which an arbitrary and predetermined distribution can be easily formed in the thickness of a blanket, and the distribution of this thickness can be easily changed using the same die. .

[0014]

According to the first aspect of the present invention, there is provided an ink carrying surface of a printing blanket, and a pair of flat molds corresponding to the back surface of the ink carrying surface and the back surface thereof. Of the two dies, the inner surface of one of the dies, which faces the other die, is a shaping surface that shapes the ink-carrying surface of the printing blanket.
An inner surface facing one of the molds is a forming mold that is a shaping surface for shaping the back surface of the printing blanket, and at least one of the two molds has an inner surface and an outer surface back to back. The reinforcing member is reinforced by at least one reinforcing member, and the reinforcing member has a predetermined position on a surface that comes into contact with the outer surface of the mold, or a step is provided between the plurality of reinforcing members, and the mold has the For a printing blanket, a three-dimensional surface having a predetermined size and shape corresponding to the step is formed at a predetermined position of the shaping surface of the mold by being deformed according to the step. It is a molding die.

According to the second aspect of the present invention, the step is formed by inserting a thin plate-like spacer at a predetermined position between the outer surface of the mold and the surface of the reinforcing member which comes into contact with the outer surface of the mold. The molding die for a printing blanket according to claim 1, wherein the molding die is formed. According to the third aspect of the present invention, a pair of dies are disposed vertically, and the upper one of the dies is reinforced by a reinforcing member on the outer surface facing the inner surface with the inner surface facing downward with the inner surface facing downward. The molding die for a printing blanket according to claim 1, wherein the lower die is placed on a base plate having a flat surface with its inner surface facing upward. It is.

According to a fourth aspect of the present invention, the thickness of the pair of molds is 100% of the thickness of the printing blanket to be formed.
2. The molding die for a printing blanket according to claim 1, wherein the number is not more than twice. The invention according to claim 5 is the molding die for printing blanket according to claim 1, wherein the reinforcing member is a structural steel or a structural steel pipe. In the invention according to claim 6, the shaping surface for shaping the ink carrying surface of the printing blanket is formed on the surface of a flat shaping member which is detachably attached to the inner surface of one of the molds. The molding die for a printing blanket according to claim 1, wherein:

According to a seventh aspect of the present invention, there is provided a suction hole for mounting a shaping member by vacuum suction on the inner surface side of one of the molds.
The molding die for a printing blanket according to claim 6, wherein a suction groove is formed. Claim 8
The invention as set forth in claim 1 is the molding die for printing blanket according to claim 1, wherein the shaping surface for shaping the ink carrying surface of the printing blanket is a mirror-finished smooth surface.

In the molding die according to the first aspect of the present invention, at least one of a pair of flat die corresponding to the ink carrying surface of the printing blanket and the back surface that is back to back with the ink carrying surface. The reinforcing member is reinforced by a reinforcing member on the inner surface and the outer surface back to back. Thus, the elastic material, such as silicone rubber, resists swelling upon curing, resulting in irregular distortion of the mold and, consequently, in areas of equal design thickness in one and the same printing blanket, or in different areas. Irregular thickness variations between the same positions of the printing blanket can be reliably prevented.

Accordingly, the thickness and weight of the mold itself can be made smaller than before so that the labor and cost involved in manufacturing can be reduced, and the handleability during use can be improved. Further, in the molding die, the die is deformed into an arbitrary shape corresponding to the step by a predetermined position of a surface of the reinforcing member that abuts on the outer surface of the die or a step provided between the plurality of reinforcing members. By doing so, a three-dimensional surface having a predetermined size and shape corresponding to the step can be easily formed at a predetermined position of the shaping surface of the mold without performing a complicated processing step. Moreover, the three-dimensional surface can be easily changed only by changing the shape and position of the step provided on the reinforcing member.

Therefore, according to the present invention, an arbitrary and predetermined distribution can be easily formed in the thickness of the printing blanket to be molded, and the distribution of the thickness can be easily changed by using the same mold. Becomes possible. The step may be directly formed on the reinforcing member by processing the reinforcing member, for example, on a surface of the reinforcing member that comes into contact with the outer surface of the mold, but may be formed on the outer surface of the mold as described in claim 2. Preferably, the step is formed by inserting a thin plate-shaped spacer at a predetermined position between the reinforcing member and the surface that comes into contact with the outer surface of the mold.

With this configuration, it is not necessary to process not only the mold but also the reinforcing member, so that the processing time can be further reduced. Further, when the thickness distribution is changed, it is only necessary to change the shape of the spacer and the position at which the spacer is formed, so that the change is simple, and there is no need to replace the reinforcing member. Reinforcement by the reinforcing member may be performed on both of the pair of molds constituting the molding die, but when the molding die is actually used, the pair of molds may be arranged vertically. In many cases, in this case, the upper mold is placed with its inner surface facing downward, as described in claim 3.
It is preferable that the lower die is placed on a flat base plate with the inner surface facing upward, while the reinforcing member is reinforced by the reinforcing member on the outer surface side of the inner surface and the back surface.

In such a configuration, the lower mold has its own weight, the weight of the upper mold and the reinforcing member, or the pressure of the mold when clamping with a clamp or the like. Since the flatness is maintained by being pressed against the surface of the board, the thickness of the lower mold is made as small as the thickness of the upper mold reinforced by the reinforcing member, and the labor and cost required for manufacturing are reduced. , And the handleability during use is improved, and the structure can be simplified by omitting the reinforcing member.

The thickness of the pair of molds is set to ensure the above-described effect of reducing the thickness and weight.
Further, in order to deform the mold by the step formed on the reinforcing member and to easily form a three-dimensional surface on the shaping surface, as described in claim 4, each of the printing blankets to be molded is formed. Preferably, the thickness is about 100 times or less. As the reinforcing member, as described in claim 5, for example, a structural steel or a structural steel pipe having various sizes and shapes for a machine structure or the like is commercially available. This is preferable in that it is easy and suppresses an increase in cost.

According to a sixth aspect of the present invention, one of the molds corresponding to the ink carrying surface of the printing blanket has a shaping surface for shaping the ink carrying surface. It is preferably formed on the surface of a flat shaping member removably attached to the inner surface of the mold. With this configuration, it is possible to reuse the molding die without replacing the shaping member only when the shaping surface is damaged as described above, for example, by replacing the shaping member, It is further advantageous in terms of maintenance and cost.

In the case where the shaping member is used, a seventh aspect of the present invention is provided.
As described in the above, on the inner surface side of one of the molds, a suction hole or a suction groove for mounting the shaping member by vacuum suction is formed, and the shaping member is attached and detached by vacuum suction. This is preferable in terms of easy attachment and detachment. As described above, the configuration of the molding die of the present invention is suitable for molding a printing blanket for precision printing, in which the finishing accuracy of the ink carrying surface is high, in which case, as described in claim 8, In addition, the shaping surface for shaping the ink carrying surface is a mirror-finished smooth surface.

[0026]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS A molding die according to the present invention will be described below with reference to the drawings showing an example of the embodiment. As shown in FIG. 1 (a), a molding die M of this example includes an ink carrying surface of a printing blanket and a pair of flat molds 1 and 2 corresponding to the back surface of the ink carrying surface and the back surface thereof. It is arranged in.

The mold 1 is disposed on the upper side with the inner surface 10 corresponding to the ink carrying surface facing downward, and a flat shaping member 4 is provided on the inner surface 10. The surface of the shaping member 4 facing the inner surface 20 of the mold 2 on the lower side in the figure is a shaping surface 40 for shaping the ink carrying surface of the printing blanket. I have. The mold 1 is reinforced by a plurality of (three in the figure) H-shaped steels 3 as reinforcing members on the outer surface 11 side (upper side) of the inner surface 10 and back to back.

In order to reinforce the mold 1 with the H-shaped steel 3..., In the example shown in FIG.
Are used to fix H-section steels 3. That is, FIG.
As shown in FIG. 2 (b), a large number of through holes 31b are formed in the lower horizontal plate portion 31 constituting the surface 31a of the H-shaped steel 3 which comes into contact with the outer surface 11 of the mold 1, and the mold is 1 outer surface 11
Of the screw holes 1 at positions corresponding to the through holes 31b.
1a are formed, and the bolts B are screwed into the screw holes 11a through the through holes 31b and tightened, so that the H-shaped steel members 3 are fixed to the outer surface 11 side of the mold 1, and The mold 1 is reinforced.

At the time of this fixing, in the example shown in the figure, a rectangular H-shaped steel 3 of the three pieces has a rectangular shape between the outer surface 11 and the surface 31a which comes into contact with the outer surface 11 of the mold 1. By inserting a plurality of (four in the figure) spacers S in a thin plate shape, a step is provided at a predetermined position on the surface of the H-section steel 3 that comes into contact with the outer surface 11. By providing this step, the mold 1 is deformed, and the inner surface 10 of the mold 1 is deformed.
Side of the shaping surface 40 which is the surface of the shaping member 4,
At a position immediately below the spacer S corresponding to the step surface, a convex surface 40b is formed as a three-dimensional surface that protrudes more smoothly toward the mold 2 than the surrounding flat portion 40a.

The thickness, size, arrangement, etc. of the spacers S and how much a three-dimensional surface is formed are delicately determined based on the thickness of the mold 1 and other factors. Because it is different, the dimensions of the target three-dimensional surface,
It is preferable to set the thickness, the size, the arrangement, and the like of the spacer S while considering the shape and the like. For example, in the fixed structure in the figure,
When the mold 1 and the H-shaped steel 3 sandwiching the spacer S are tightened by the bolts B, not only the mold 1 but also the horizontal plate portion 31 of the H-shaped steel 3 is in the same direction as the deformation direction of the mold 1. Since it is slightly deformed in the opposite direction, the projection height of the convex surface 40b as a three-dimensional surface is a value slightly smaller than the thickness of the spacer S. Therefore, it is necessary to set the thickness of the spacer S in consideration of the protruding height of the convex surface 40b. For this purpose, back data such as the relationship between the spacer thickness and the protruding height of the convex surface is obtained in advance, and the data is molded. It is good to refer to when assembling the mold M.

The convex surface 40b in the illustrated example is not independent for each of the four spacers S, but has one continuous mountain shape straddling the four spacers S. This is because the interval between the adjacent spacers S is set to be narrow, and the deformation of the mold 1 does not follow this narrow gap. Therefore, as the spacer S, a continuous long strip-shaped one corresponding to the above-mentioned four sheets may be used.
As shown in FIG. 2 (a), the printing blanket BL formed by using the forming mold M in the figure provided with the convex surface 40b is as follows.
A concave portion BL2 recessed at a constant width over substantially the entire width in the width W direction of the printing blanket BL corresponding to the convex surface 40b at a central portion of the ink carrying surface BL1 formed by the forming surface 40; Become.

The printing blanket BL has a width W, for example.
A portion in which the concave portion BL2 is shallow at both ends in the direction is cut out, and the central portion in the length L direction can be used for printing, for example, in a state having a thickness distribution in which the center portion is thin and the front and rear portions are thick. In this case, the size to be molded should be set to be larger by the amount to be cut so that the printing blanket after cutting both ends in the width W direction as described above becomes the size to be actually used for printing. It is important.

Although not shown, the same shape as above,
The surfaces 31a, 31a of the two H-shaped steels 3, 3 on both sides, which are in contact with the outer surface 11 of the mold 1, and the outer surface, 11 is inserted between each of them and four convex surfaces having the same shape as described above are provided at two places of the shaping surface 40. Printing formed using a molding die provided with such convex surfaces As shown in FIG. 2 (b), the blanket BL is printed on the ink carrying surface BL1 formed by the shaping surface 40 at two positions at the front and rear ends in the length L direction corresponding to the convex surface. The blanket BL has concave portions BL2 and BL2 recessed at a constant width over substantially the entire width in the width W direction.

The printing blanket BL has a width W, for example.
The recesses BL2, BL2 at both ends in the length direction are cut off, and the recesses BL at both ends in the length L direction are also cut out.
2. The portion where BL2 becomes shallow is cut out, and it can be used for printing, for example, in a state having a thickness distribution in which the center portion in the length L direction is thick and the front and rear portions are thin. Also in this case, the width W direction and the length L
It is important that the size to be formed is set to be larger by the amount to be cut so that the printing blanket after cutting both ends in the direction becomes the size to be actually used for printing.

The spacer S may be formed so as to protrude from the horizontal plate portion 31b of the H-section steel 3 depending on the size and shape of the three-dimensional surface formed on the shaping surface 40. In that case, the H-section steel 3 and the mold 1 may be fixed by bolts B at positions where they do not interfere with the spacer S. The mechanism by which the shaping member 4 constituting the shaping surface 40 can be detachably attached to the inner surface 10 of the mold 1 is not particularly limited. For example, as shown in FIG. Are formed, and each of the suction holes 12a is formed inside the mold 1 by a pipe 12b.
, 12c, and vacuum-suctioned from the outside of the mold 1 using a suction device (pump or the like) (not shown) as shown by a white arrow in the figure, so that the shaping member 4 is placed on the inner surface of the mold 1. 10 and by stopping the vacuum suction, the shaping member 4
Is preferably detached from the inner surface 10 of the mold 1.

Also, as shown in FIG.
0, a suction groove 13a is formed, and the suction groove 13a is connected to a pipe 13c formed inside the mold 1 through a through hole 13b. The shaping member 4 is mounted on the inner surface 10 side of the mold 1 by vacuum suction as shown by a white arrow in the figure, and the shaping member 4 is stopped by stopping the vacuum suction. May be detached from the inner surface 10 side.

As the shaping member 4, for example, when the molding die M shown in the figure is used for molding a printing blanket for precision printing having a high finishing accuracy of the ink carrying surface, as described above, A plate material whose shaping surface is mirror-finished, such as a plate or a polished metal plate, is suitably used. As the reinforcing member, in addition to the H-shaped steel members 3,.
For example, a square steel pipe 3 'shown in FIG. 4 can be used.

The lower mold 2 combined with the above mold 1
Is used by being placed on a flat base plate (not shown) with its inner surface 20 facing upward, and as described above, its own weight, Since the upper mold 1 and the H-section steel 3 are pressed against the surface of the base plate by the weight of the H-shaped steel 3 and the clamping pressure to maintain the flatness, no reinforcing member is provided. As described above, the thickness of each of the molds 1 and 2 is set to be 1 thickness of the printing blanket to be formed.
It is preferably at most 00 times. The reason is as described above. In addition, the thickness of the molds 1 and 2 was reduced to reduce the labor and cost required for manufacturing the molding mold M, to improve the handleability during use, and to be deformed by the step formed on the reinforcing member. At this time, in order to further clarify the effect of the present invention that the three-dimensional surface is easily formed on the shaping surface, the two molds 1 and 2 are used.
In particular, the thickness of 2 is preferably about 60 times or less the thickness of the printing blanket to be formed, even within the above range.

However, when the thicknesses of both the dies 1 and 2 are too small, the expansion of the elastic material such as silicone rubber during curing, despite being reinforced by the reinforcing members such as the H-section steel 3. When the molds 1 and 2 are distorted or the gap between the molds is widened, the thickness of the printing blanket becomes equal in the same design blanket in one and the same printing blanket.
Alternatively, there is a possibility that irregular large variations occur between the same positions of a plurality of different printing blankets.

Therefore, the thickness of the two dies 1 and 2 is preferably at least 30 times, more preferably at least 50 times the thickness of the printing blanket to be formed. In FIG. 1, reference numeral 5 denotes a lower surface 40 of the shaping member 4 which is a shaping surface corresponding to the ink carrying surface of the printing blanket, and an inner surface of the lower mold 2 which is a shaping surface corresponding to the back surface of the printing blanket. 20 is an inter-mold spacer interposed between the two molding surfaces to form a gap corresponding to the thickness of the printing blanket between the two shaping surfaces.

The steps of manufacturing a printing blanket using room temperature curing type or heat curing type liquid silicone rubber using the molding die M shown in FIG. 1 having the above-mentioned parts are as follows. First, the above-mentioned parts are arranged in the order shown in FIG. 1, that is, the inner surface 2 of the lower mold 2 placed on a base plate (not shown).
On the inner surface 10, the shaping member 4 is mounted, and on the outer surface 11, the outer surface 11 is reinforced with H-shaped steel 3.
Are laminated on the shaping surface 40 and the mold 1 on which a three-dimensional surface such as the convex surface 40b is formed, and if necessary, a clamp or the like (not shown) arranged around the molds 1 and 2 is used. Close the mold.

Next, in this state, the mold 1 and the shaping member 4
., 4a.. Formed in each of the four corners, liquid silicone rubber is injected from the other three through holes 1a. Fill the gaps between the faces. Next, in the case of the room temperature curing type, the molding die is heated as it is, or in the case of the heat curing type, the entire molding die is heated to a temperature required for curing the silicone rubber, and each is left for a certain period of time to leave the silicone rubber. After curing, is removed from the mold, and if necessary, is cut out to a predetermined size as described above, and is subjected to a predetermined post-treatment such as surface polishing to produce a printing blanket.

The molding die M shown in FIG. 1 can also be used for a method for producing a printing blanket using a heat-curable millable silicone rubber.
This is the same as the above except that the millable silicone rubber is placed on the inner surface 20 of the mold 2 before the mold 1 is laminated, and then the mold 1 is laminated. That is, first, the lower mold 2 is placed on a platform (not shown), and the above-mentioned millable silicone rubber and the spacer 5 are laminated on the inner surface 20 of the mold 2.

Next, the shaping member 4 is placed on the inner surface 10 side.
, And the outer surface 11 side is reinforced with H-shaped steel, and spacers S are inserted into a part of the
And a mold 1 on which a three-dimensional surface such as a convex surface 40b is formed.
Further, if necessary, the mold is clamped by a clamp or the like (not shown) arranged around the dies 1 and 2. Then, in this state, the entire molding die M is heated to a temperature required for curing the silicone rubber and left for a certain period of time to cure the silicone rubber, and then removed from the mold. The printing blanket is manufactured by performing predetermined post-treatments such as cutting into pieces and surface polishing.

The printing blanket to be manufactured may be reinforced with a resin sheet, a fiber cloth, or the like, or may incorporate a functional component such as a sheet heater. For this purpose, in a state where the above-mentioned sheet, fiber cloth, functional parts, etc. are mounted at a predetermined position in the mold in advance, liquid silicone rubber is injected, or millable silicone rubber is placed, and the above procedure is performed. What is necessary is just to shape | mold.

[0046]

The present invention will be described below based on examples and comparative examples. Example 1 <Configuration of Molding Mold M> Molds 1 and 2: Both 1100 mm long, 900 mm wide,
It was formed of a stainless steel plate having a thickness of 50 mm.

Reinforcing member: Nominal dimensions (JIS G319)
2) Three H-shaped steel members 3 each having a size of 120 mm x 120 mm and a length of 900 mm were used. Spacer S: length 120mm, width 80mm, thickness 0.2m
m, four rectangular and thin plate-shaped spacers S were used. Reinforcement and insertion method of spacer S: the above three H-sections 3
.. Are placed on the outer surface 11 side which is the upper surface of the upper mold 1 as shown in FIG.
As shown in FIG. 3A, a plurality of bolts B are fixed in parallel to the lateral direction to reinforce.

In the above fixing, the surface 31a of the central H-section steel 3 of the three which comes into contact with the outer surface 11 of the mold 1 is used.
By inserting the four spacers S... Between the outer surface 11 and the outer surface 11 as shown in FIGS.
A step is provided at a predetermined position on a surface that comes into contact with the outer surface 11. Due to this step, one continuous, mountain-shaped convex surface 40b straddling the four spacers S is formed on the forming surface 40 of the forming member 4 described below. Convex surface 40
The protrusion height of b was 0.15 mm as a result of the H-shaped steel 3 being offset by the deformation of the horizontal plate portion 31.

Shaped member 4: 1100 mm long, 900 m wide
A glass plate having a thickness of 5.0 mm and a thickness of 5.0 mm was used. Spacer 5: formed of a stainless steel plate having a thickness of 0.85 mm. <Liquid Silicone Rubber> Room temperature curing type liquid silicone rubber KE1603 [manufactured by Shin-Etsu Chemical Co., Ltd.]
03AL) and a curing agent (KE1603BL) in a ratio of 1: 1 (weight ratio) of main agent: curing agent, and then subjected to vacuum defoaming.

<Manufacture of Printing Blanket> As described above, the lower mold 2, the spacer 5, and the shaping member 4 on the inner surface 10 side are mounted on the base (not shown), and three outer surfaces 11 are provided. H-shaped steel 3 ...
Four spacers S were inserted between the outer surface 11 and the outer surface 11, and the mold 1 having the convex surface 40b formed on the shaping surface 40 was laminated in this order. Next, from one of the four through holes 1a... 4a formed at the four corners of the mold 1 and the shaping member 4,
The above liquid silicone rubber is transferred to the other three through holes 1a.
a) to fill the gap between the two shaping surfaces by injecting it to the extent that it slightly overflows.

After leaving the silicone rubber at room temperature for 21 hours to cure the silicone rubber, the silicone rubber was taken out of the mold,
2 mm, width 900 mm, thickness 0.85 mm, and FIG.
As shown in (a), the ink blanking surface BL1 shaped by the shaping surface 40 is recessed at a constant width over substantially the entire width in the width W direction of the printing blanket BL corresponding to the convex surface 40b. A printing blanket having a concave portion BL2 having a thickness of 0.7 mm was manufactured.

The concave portion BL2 of the obtained printing blanket
The variation in the in-plane thickness of the ink carrying surface BL1 and the bottom surface of the concave portion BL2 other than the above was measured, and it was confirmed that each of them was 10 μm, which satisfied the above-mentioned standard for liquid crystal color filter printing. Was done. The maximum swelling amount of the upper mold 1 measured during curing of the silicone rubber was 20 μm. In addition, the molding die M did not require much labor in manufacturing the dies 1 and 2, and was excellent in handleability because both dies 1 and 2 were light.

Further, when the molding die M is damaged on the imprinting surface corresponding to the ink carrying surface of the printing blanket,
It was only necessary to replace the shaping member, and the maintenance was excellent. Example 2 As a reinforcing member, length 120 mm, width 120 mm, thickness 1
A molding die M was constructed in the same manner as in Example 1 except that three rectangular steel pipes 3 'each having a length of 0 mm and a length of 900 mm were used, and a printing blanket was manufactured. For fixing square steel pipes,
As in the first embodiment, a bolt B was used.

The obtained printing blanket BL1 is shown in FIG.
As shown in (a), the ink carrying surface BL has the same dimensions and the same shape as those of the first embodiment, and is other than the concave portion BL2.
1 and the variation in the in-plane thickness at the bottom surface of the concave portion BL2 were measured, and all of the variations were 7 μm.
It was confirmed that the above-described standard for liquid crystal color filter printing was satisfied. The maximum swelling amount of the upper mold 1 measured during curing of the silicone rubber is 15
μm.

In addition, the molding die M did not require much labor for manufacturing the dies 1 and 2, and was excellent in handleability because both dies 1 and 2 were light. Further, the above molding die M
Was only required to replace the shaping member when the shaping surface corresponding to the ink carrying surface of the printing blanket was damaged, and was excellent in terms of maintenance. Example 3 Except that eight spacers S having the same dimensions and the same shape as those described above were prepared, and four spacers S were inserted between the two H-section steels 3, 3 on both sides and the outer surface 11 instead of the center. A molding die M was formed in the same manner as in Example 1, and a printing blanket was manufactured.

The obtained printing blanket is 1100 m long.
m, width 900 mm, thickness 0.85 mm, and FIG. 2 (b)
As shown in (2), two portions at the front and rear ends in the length L direction of the ink carrying surface BL1 shaped by the shaping surface 40 are recessed at a constant width over substantially the entire width in the width W direction of the printing blanket BL. , 0.7 mm thick concave portions BL2, BL2
It had the following. When the dispersion of the in-plane thickness of the printing blanket on the ink carrying surface BL1 other than the concave portion BL2 and the bottom surfaces of the two concave portions BL2 and BL2 was measured, each of them was 10 μm. It was confirmed that the standards for use were cleared. The maximum swelling amount of the upper mold 1 measured during curing of the silicone rubber is 20 μm.
Met.

Further, the molding die M did not require much labor in manufacturing the dies 1 and 2, and was excellent in handleability because both dies 1 and 2 were light. Further, the molding die M could be easily constructed simply by changing the number of spacers and the insertion position by using the dies 1 and 2 used in the example. Further, when the molding surface corresponding to the ink carrying surface of the printing blanket is damaged, the molding die M only needs to replace the molding member, and is excellent in terms of maintenance.

COMPARATIVE EXAMPLE 1 Since the upper mold was not reinforced by the reinforcing member and the mold could not be deformed with the spacer interposed therebetween, the first embodiment was replaced with the same position on the inner surface of the mold. A molding die was formed in the same manner as in Example 1 except that the same convex surface as that when the mold 1 was deformed with the spacer interposed therebetween was formed by cutting, and a printing blanket was manufactured.

The obtained printing blanket BL1 is shown in FIG.
As shown in (a), the same dimensions and the same shape as in Example 1 were used, but the variation in the in-plane thickness of the ink carrying surface BL1 other than the concave portion BL2 and the bottom surface of the concave portion BL2 was measured. Both of them were 350 μm, and it was found that the above-mentioned criteria for liquid crystal color filter printing could not be satisfied. The maximum swelling amount of the upper mold measured during curing of the silicone rubber is 550 μm.
m.

Further, the above-mentioned molding die has a problem that it takes time and effort to produce the convex surface on the upper die. Comparative Example 2 A molding die was formed in the same manner as in Comparative Example 1 except that a shaping surface having a convex surface was formed directly on the inner surface of the upper mold without using the shaping member. Manufactured.

The obtained printing blanket BL1 is shown in FIG.
As shown in (a), the same dimensions and the same shape as in Example 1 were used, but the variation in the in-plane thickness of the ink carrying surface BL1 other than the concave portion BL2 and the bottom surface of the concave portion BL2 was measured. Both of them were 350 μm, and it was found that the above-mentioned criteria for liquid crystal color filter printing could not be satisfied. The maximum swelling amount of the upper mold measured during curing of the silicone rubber is 550 μm.
m.

In addition, the above-mentioned molding die requires a lot of trouble particularly in the production of the upper die, and when a shaping surface directly formed on the inner surface of the upper die is damaged, re-polishing is required. It was troublesome, and there was a problem in terms of maintenance. Table 1 summarizes the above results.

[0063]

[Table 1]

[Brief description of the drawings]

FIG. 1 (a) is an exploded perspective view showing an example of an embodiment of a molding die for a printing blanket of the present invention, and FIG. 1 (b).
FIG. 2 is an enlarged sectional view of a main part of the molding die.

FIG. 2A is a perspective view showing an appearance of a printing blanket formed by using the above-described molding die, and FIG. 2B is a perspective view showing an appearance of a modified example of the printing blanket. .

FIGS. 3 (a) and 3 (b) are plan views each showing a structure for adsorbing a shaping member, which is formed on the inner surface of an upper mold of the printing blanket molding mold. is there.

FIG. 4 is a perspective view showing a modification of a reinforcing member used in the printing blanket forming die.

[Explanation of symbols]

 M Mold 1, 2 Mold 10, 20 Inner surface 11 Outer surface 3 H-shaped steel (reinforcing member) 40 Shaping surface 40b Convex surface (three-dimensional surface) S Spacer

 ────────────────────────────────────────────────── ─── Continued on the front page (72) Inventor Jun Nishibayashi 3-6-9, Wakihama-cho, Chuo-ku, Kobe-shi, Hyogo F-term in Sumitomo Rubber Industries, Ltd. (Reference) 2H114 AA04 CA04 CA10 EA04 EA08 GA12

Claims (8)

[Claims] An ink carrying surface of a printing blanket, and a pair of flat molds corresponding to the back surface of the ink carrying surface and the back of the ink carrying surface, wherein one of the two dies is the other of the two dies. And an inner surface facing the ink blanking surface of the printing blanket, and an inner surface of the other mold facing the one mold, and a shaping surface shaping the back surface of the printing blanket. A molding die, wherein at least one of the two dies is reinforced by at least one reinforcing member on the outer surface side of the inner surface and back to back, and the outer surface of the die of the reinforcing member. And a step is provided between the plurality of reinforcing members, and the mold is deformed in accordance with the step, thereby forming a predetermined position on the shaping surface of the mold. , Predetermined dimensions and shapes corresponding to the steps Molding die for a printing blanket, wherein the solid surface is formed to have. 2. The method according to claim 1, wherein the step is formed by inserting a thin plate-shaped spacer at a predetermined position between the outer surface of the mold and a surface of the reinforcing member which comes into contact with the outer surface of the mold. The molding die for a printing blanket according to claim 1, wherein 3. A pair of dies are vertically arranged, and the upper one of the dies is reinforced by a reinforcing member on the outer surface facing the inner surface with the inner surface facing downward with the inner surface facing downward. 2. The molding die for printing blanket according to claim 1, wherein the lower die is placed on a base plate having a flat surface with its inner surface facing upward. 4. The printing blanket forming die according to claim 1, wherein the thickness of the pair of dies is 100 times or less the thickness of the printing blanket to be formed. 5. The mold according to claim 1, wherein the reinforcing member is a structural steel or a structural steel pipe. 6. A shaping surface for shaping an ink-carrying surface of a printing blanket is formed on a surface of a flat shaping member removably attached to an inner surface of one of the molds. The molding die for a printing blanket according to claim 1, wherein 7. A printing blanket according to claim 6, wherein a suction hole or a suction groove for mounting the shaping member by vacuum suction is formed on an inner surface side of one of the molds. Molding mold. 8. The printing blanket mold according to claim 1, wherein the shaping surface for shaping the ink carrying surface of the printing blanket is a mirror-finished smooth surface.