JP2589635B2 - Blanket molding dies for precision printing - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a blanket mold for precision printing.

[0002]

2. Description of the Related Art Recently, precision printing by the offset method has been attracting attention in the field of electronic circuit printing. Due to the nature of offset printing, printing performance is affected by the finishing accuracy of the blanket surface. Particularly when manufacturing color filters, it is necessary to print very fine lines densely, so that a high precision is required for finishing the surface of the blanket, and the blanket is required to have a uniform thickness. You.

[0003] Generally, a blanket is formed by laminating a rubber layer and a cloth layer three to four times, and the surface thereof is a rubber layer. Conventionally, a rubber paste is applied to the cloth layer and vulcanized and cured, and then the surface of the blanket, which is to be the ink-carrying surface, is buff-polished with paper or a grindstone. However, according to this method, the surface roughness and thickness accuracy of the ink carrying surface required by the blanket for precision printing cannot be satisfied.

[0004]

In view of the above, a method of manufacturing by heating and pressing using an upper mold and a lower mold has been attempted. According to this manufacturing method, the finishing accuracy of the surface serving as the ink carrying surface of the blanket is determined by the finishing accuracy of the inner surface of the mold. In this case, a mold made of stainless steel or the like in consideration of corrosiveness or the like was used, and the inner surface was finished to the surface roughness accuracy required for the blanket.

Incidentally, the precision required for a blanket for precision printing is, specifically, that the surface roughness is 3 to 10 in Rz.
μ or less (preferably 3 μ or less), and the blanket thickness accuracy is ± 10 μm or less. Inevitably, the same level of surface roughness accuracy is required on the pressing surface of the mold. However, in order to perform mirror finishing on the inner surface of a conventional die made of stainless steel or the like that satisfies the above surface roughness accuracy, an extremely large number of steps are required, and the cost is greatly increased. In addition, the mirror-finished inner surface cannot be used as a precision blanket molding die if it is slightly scratched, and the inner surface of the die must be polished again. Therefore, maintenance for maintaining the accuracy of the inner surface of the mold requires a great deal of cost.

An object of the present invention is to provide a blanket molding die for precision printing which satisfies the required precision at low cost and which is easy to maintain for maintaining the precision of the die.

[0007]

A blanket forming mold for precision printing according to claim 1 is a blanket forming mold for precision printing provided with a pair of molds. A plate member made of a glass plate, a ceramic plate, or a thin metal plate having a flat surface for forming an ink carrying surface of a blanket is detachably attached to an inner surface of one of the molds.

According to a second aspect of the present invention, there is provided a blanket forming mold for precision printing, wherein a suction hole or a suction groove for vacuum suctioning the plate member is provided on an inner surface of the die to which the plate member is attached. It is characterized by the following.

[0009]

According to the blanket forming die according to the first aspect of the present invention, the inner surface of the die for heating and pressing the blanket is provided on the inner surface of the die.
By providing a relatively inexpensive plate member consisting of a glass plate, ceramic plate or thin metal plate that can achieve high accuracy of surface roughness, there is no need to precisely finish the inner surface of the mold itself, resulting in significant cost reduction. The precision blanket can be formed while satisfying the surface roughness accuracy required by the precision blanket. Further, since the plate member is detachable, even if the plate member is damaged, it is only necessary to replace the plate member, and the mold can be easily maintained.

Further, according to the blanket molding die according to the second aspect, since the plate member is attached to the inner surface of the die by vacuum suction, removal is extremely simple, and maintenance of the die is further facilitated. I can do it.

[0011]

BRIEF DESCRIPTION OF THE DRAWINGS FIG. FIG. 1 is a partially sectional perspective view showing a blanket manufactured by a mold according to an embodiment of the present invention. Referring to FIG. 1, reference numeral A denotes a blanket molding die, which includes an upper die 1, a glass plate 4 as a plate member attached to the upper die 1, a lower die 2, and an upper die 1. And a lower mold 2.

FIG. 2 shows a state in which the glass plate 4 is attached to the upper mold 1. The upper die 1 is made of stainless steel, and a plurality of suction holes 11 extending from the inner surface 13 to the inside of the upper die 1 are provided in the inner surface 13 of the upper die 1. A tapered screw hole 1e is formed in the side surface 1c of the upper mold 1,
A collecting hole 12 extending from the screw hole 1e to the inside of the upper mold 1 perpendicular to the side surface 1c is provided. The plurality of suction holes 11 are all connected to and connected to the collecting holes 12. Further, a glass plate 4 is fitted on the inner surface 13 of the upper mold 1, and the glass plate 4 is connected via a suction hose (not shown) screwed into the tapered screw hole 1 e.
The inner surface 13 of the upper mold 1 is evacuated by vacuum suction means.
Is adsorbed. The lower surface of the glass plate 4 becomes a blanket forming surface 41 when the blanket is heated and pressed, and has a surface roughness Rz of 3 μm or less.

The lower mold 2 is made of stainless steel, and serves as a base on which a blanket material to be formed is laminated and placed on the upper surface 21 thereof. FIG. 3 is a schematic view showing a state in which the blanket material is heated and pressed. On the upper surface 21 of the lower mold 2, several layers of a base cloth layer 51 as a cloth layer and a rubber layer 52 are laminated. In this case, the cloth layer may be a resin film or a thin metal plate. The blanket material formed by laminating several layers is heated and pressed by the upper mold 1 from above to form a blanket.

The spacer 3 is a frame-shaped member for positioning the upper die 1 and the lower die 2 in the vertical direction when pressing the blanket. The spacer 3 includes an upper surface 21 of the lower mold 2 and a blanket molding surface 4 of the upper mold 1.
1 to adjust the thickness of the blanket to be formed. In order to obtain the required thickness accuracy, it is preferable that the thickness of the upper and lower molds 1 and 2 be equal to or more than 1/7 of the outer diameter of the mold.

FIG. 4 is a schematic diagram showing the positional relationship among the upper mold 1, the glass plate 4 and the spacer 3 when the blanket is pressed. The spacer 3 is an inner peripheral edge 3 of the spacer 3.
1 and an outer peripheral edge 42 of the glass plate 4 are positioned with respect to the upper mold 1 so as to form a predetermined gap. This gap is
It serves as an escape groove 6 for releasing the excess of blanket material when blanket is formed.

Referring to FIG. 1 again, according to this embodiment, the blanket material placed on the upper surface 21 of the lower mold 2 is heated and pressed by the upper mold 1 from above. At this time, the blanket molding surface 41 has a surface roughness of 3 in Rz.
Since the mirror finish is less than μ, the formed blanket can satisfy the surface roughness required by the precision blanket. Furthermore, this glass plate 4 can be finished at a low cost to the surface roughness required by the precision blanket.

The glass plate 4 is detachably attached to the upper mold body 1a by vacuum suction and can be easily removed. Therefore, even if the blanket molding surface 41 is damaged, It is only necessary to replace the glass plate 4, and maintenance for maintaining the accuracy of the mold can be easily performed. Furthermore, when the heat and pressure molding is performed, the extra blanket material is extruded into the clearance groove 6 formed around the glass plate 4 and the blanket material is press-molded under a uniform compressive stress state. The blanket has the same thickness accuracy as the precision blanket (± 10
μ or less) can be satisfied.

Here, the results of a study on the dimensions of the escape groove 6 will be described. The test results of the relationship between the volume of the clearance groove 6 and the surface condition and thickness accuracy of the formed blanket are shown. -In the case of the relief groove volume ratio of 15%, the surface condition is poor because air entrapment is observed in each part of the product.

Burrs occur at the product thickness accuracy of ± 30 μm, and the thickness accuracy is poor. -When the volume ratio of the escape groove is 18%, the surface condition is poor because air entrapment portions are observed in each part of the product. Burrs occur at a product thickness accuracy of ± 15 μ, and the thickness accuracy is poor. -When the volume ratio of the clearance groove is 20%, the surface condition is excellent because the same surface roughness accuracy as that of the mold side is obtained.

The product thickness accuracy is ± 10 μm or less, no burrs are generated, and the thickness accuracy is good. -In the case of the relief groove volume ratio of 25%, the surface condition is excellent because the same surface roughness accuracy as that of the mold side is obtained. The product thickness accuracy is ± 10 μm or less, no burrs are generated, and the thickness accuracy is good. However, the four corners of the product will be missing unless the amount of materials charged is increased.

Therefore, it is considered that the volume of the clearance groove 6 needs to be 20% or more of the finished volume of the blanket. Note that the present invention is not limited to the above-described embodiment, and a ceramic member may be used as a plate member in addition to a glass plate, or a surface roughness accuracy required by a precision blanket molding die. A rolled strip steel plate such as an SK material or other thin metal plate satisfying the following conditions may be used. The surface roughness of these plate members is preferably 3 μm or less.
It is permissible in the range of 10 μm or less.

In addition to the vacuum suction, the plate member may be attached to the mold by providing a substantially L-shaped member in the mold and holding the plate member in the substantially L-shaped member. If a rolled thin metal plate or the like is used as the plate member, the plate member may be mounted on a metal mold by magnetizing the metal mold and using a magnetic force. Further, in addition to providing the plurality of suction holes 11 in the upper mold 1, a suction groove may be provided. That is, as shown in FIG.
A suction groove 11a is provided on the inner surface 13 of the upper mold 1, and the suction groove 11a communicates with a collecting hole 12 provided inside the upper mold 1 from the side surface 1c of the upper mold 1 by a communication hole 12a. ,
The plate member 4 may be attached by vacuum suction. This method is cheaper in processing cost than the method in which a large number of suction holes 11 are provided. Also, since the groove area can be widened, the attraction force is large.

In addition, various design changes can be made without changing the gist of the present invention.

[0024]

According to the blanket molding die for precision printing according to the first aspect of the present invention, a plate member such as a glass plate is used which is inexpensive and can easily obtain surface roughness accuracy. Can be provided. Further, since the plate member is detachably attached to the mold, maintenance for maintaining the accuracy of the mold is easy.

Further, according to the blanket forming die for precision printing according to the second aspect, since the removal of the plate member attached to the die by vacuum suction is extremely simple, maintenance for maintaining the accuracy of the die is further improved. Easy.

[Brief description of the drawings]

FIG. 1 is a partial cross-sectional perspective view showing a blanket manufactured by a blanket molding die for precision printing according to an embodiment of the present invention.

FIG. 2A is a front sectional view of an upper mold. FIG. 3B is a partial cross-sectional bottom view of the upper mold.

FIG. 3 is a schematic diagram showing a state in which a blanket material is pressed.

FIG. 4 is a schematic diagram showing a positional relationship among an upper mold 1, a glass plate 4 and a spacer 3 when a blanket is pressed.

FIG. 5 (a) is a front sectional view showing another embodiment of a method of attaching a plate member to an upper die. (b) It is a bottom view which shows another Example of the attachment method to the upper metal mold | die of a plate member.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Upper die 11 Suction hole 13 Glass plate mounting surface 4 Glass plate (plate member) 41 Blanket forming surface 5 Blanket

Claims (2)

(57) [Claims] 1. A blanket forming mold for precision printing comprising a pair of dies, wherein a flat surface for forming an ink carrying surface of a blanket is formed on an inner surface of one of the dies. A blanket molding die for precision printing, wherein a plate member made of a glass plate, a ceramic plate, or a thin metal plate having the above is detachably attached. 2. The blanket for precision printing according to claim 1, wherein a suction hole or a suction groove for vacuum-sucking the plate member is provided on an inner surface of a mold to which the plate member is mounted. Molding mold.