JPH09132900A - Forming mold for pulp mold, forming of pulp mold and pulp mold - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a pulp mold having desired facial shape and to provide a forming mold for forming the pulp mold and a method for forming the mold. SOLUTION: This mold 10 for forming a pulp mold is installed along a forming face 12 and a suction hole 18 is opened on the bottom and it has many water through grooves 14 for keeping clearances between the opening on a forming face 12 of the suction hole 18 and a network body 16 when suctioned from the suction hole 18. Therefore, clearances corresponding to the depth of the water-passing grooves 14 are preserved and the pulp is sucked through the water through grooves 14 also when the pulp is sucked and dehydrated. Consequently, sufficient suction force is obtained even by in a part isolated from the opening of the suction hole 18 to form the pulp of sufficient thickness and deformation of the network body 16 due to only localized sucking is suppressed to provide the objective pulp mold having desired face shape.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulp mold molded from pulp slurry, a mold for molding the pulp mold, and a molding method.

[0002]

2. Description of the Related Art When a predetermined product or the like is transported, the product or the like is packed with a package or cushioning material having a recess corresponding to the shape of the product or the like. As such a packaging and cushioning material, expanded polystyrene or the like is usually used. However, it has recently become a serious problem that these materials cause environmental pollution upon disposal.

On the other hand, for the purpose of effectively utilizing recovered resources, packaging materials are manufactured from pulp of waste paper such as corrugated board and newsprint, which can be easily disposed of,
Such packaging is called a pulp mold. Such a pulp mold usually has a molding surface having a corresponding shape and has a large number of suction holes opened in the molding surface, and the molding surface of the molding die is placed in pulp slurry. It is formed by sucking pulp from the suction hole in the immersed state and adsorbing the pulp to its molding surface, and after the adsorbed pulp is sucked and dehydrated to a water content of such an extent that the shape can be maintained, It is manufactured by releasing from the mold and drying with hot air in a drying furnace.

[0004]

The suction holes opened on the molding surface of the above-mentioned molding die are, for example, round holes having a diameter of about 3 mm and are provided at a rate of about 1 per 1 cm ² . . Therefore, if the pulp is directly adsorbed on the molding surface, there is a problem that it is difficult to form a predetermined pulp mold by being sucked into the suction hole in the state of pulp slurry and the suction hole is easily clogged. Therefore, when the above-mentioned molding die is used, usually, a mesh-like body such as a wire mesh of about # 40 formed according to the shape of the molding surface is fixed on the molding surface, and the pulp is adsorbed to the mesh-like body. Has been.

However, even if the pulp is sucked through the reticulated body as described above, after the reticulated body and the pulp come into close contact with the molding surface, the suction hole opening and the reticulated body come into close contact with each other. Only the part facing the hole, i.e. only part of the surface with a small proportion to the entire molding surface, is sucked exclusively. Therefore, the suction force is insufficient in the portion that does not face the opening of the suction hole, and the pulp is not sufficiently adsorbed to obtain the desired thickness. Since the suction force locally becomes excessive in the part facing the hole, the mesh body is recessed toward the suction hole side, and a large convex portion following the shape is formed on the surface of the molded pulp mold. At the same time, the pulp is pulled to the suction hole side through the mesh, and the pulp fibers are pulled into the suction hole side, producing a projection of the pulp,
The desired surface shape cannot be obtained.

The above-mentioned generation of pulp protrusions can be prevented by, for example, making the mesh body finer than about # 80. By doing so, even if the pulp fibers are sucked with a relatively large suction force, the pulp fibers are not drawn into the suction hole side through the mesh body, so that the protrusion of the pulp hardly occurs. However, since the fine mesh has a smaller wire diameter at the same time, the gap between the opening on the molding surface side of the suction hole and the mesh becomes smaller, and the pulp is more likely to be present in the portion not facing the opening of the suction hole. It becomes difficult to be adsorbed, which causes a problem that the thickness of the entire pulp mold becomes more uneven.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a pulp mold having a desired surface shape, a molding die capable of obtaining the pulp mold, and a molding method. To do.

[0008]

In order to achieve such an object, the gist of the molding die of the pulp mold of the present invention is that it has a large number of suction holes opened in the molding surface, Is sucked from the suction hole in the state that it is covered with a mesh, and the pulp in the pulp slurry is adsorbed on the mesh in the pulp slurry, and the adsorbed pulp is outside the pulp slurry on the molding surface. A mold for pulp mold for forming a pulp mold by dehydrating with, (a) the suction hole provided along the molding surface is opened to the inner surface thereof, and is sucked from the suction hole. In this case, a large number of water passage grooves for maintaining a gap between the opening on the molding surface side of the suction hole and the net-like body are included.

[0009]

[Effects of the First Invention] According to the present invention, the molding die of the pulp mold is formed along the molding surface, and the suction hole is opened to the inner surface thereof, and when the suction hole is sucked, the suction hole is molded. It is configured to include a large number of water passage grooves for maintaining a gap between the opening on the surface side and the mesh body. Therefore, even when pulp is adsorbed on the molding surface and when the pulp is sucked and dewatered, the depth of the water passage groove formed on the molding surface is between the opening on the molding surface side of the suction hole and the mesh body. A gap corresponding to the height will be maintained. Therefore, suction is performed through the water passage, and sufficient suction force is obtained even in the portion that does not face the opening of the suction hole, the pulp is adsorbed in a sufficient thickness, and the entire molding surface is In addition to obtaining a substantially uniform pulp thickness, it is possible to prevent the partial deformation of the mesh due to local suction of only a small area, which corresponds to the suction hole on the surface of the pulp mold. A large convex portion is not formed, and a pulp mold having a desired surface shape can be obtained. Moreover, the gap between the opening on the molding surface side of the suction hole and the net-like body is maintained in the same manner when a fine net-like body is used. It is possible to prevent the occurrence of

[0010]

[Other Aspects of the First Aspect of the Invention] Here, it is preferable that the suction hole that is opened in the inner surface of the water passage is formed along a longitudinal direction of the water passage with respect to a normal direction of the molding surface. It is provided so as to be inclined at a predetermined angle. By doing so, since the suction direction of the suction holes is along the longitudinal direction of the water passage groove, it is further suppressed that the mesh body is depressed toward the suction hole side and the suction force is more uniform over the entire molding surface. Is obtained, and a pulp mold having a better surface shape can be obtained. Moreover, when suction dewatering is performed outside the pulp slurry, the water dewatered from the pulp easily flows along the water passages to accelerate dewatering, and the dewatering rate increases to improve the shape retention after release. Will be done.

Further, preferably, at least a part of the water passage groove is provided in a pattern corresponding to a predetermined figure formed in a convex shape on the surface of the pulp mold.
By doing so, the pulp adsorbed on the molding surface is slightly projected toward the water passage groove together with the mesh body by being sucked from the suction hole, so that the surface of the pulp mold to be molded is A minute convex portion corresponding to the water passage is formed, but at least a part of the water passage is provided in a pattern corresponding to a figure (for example, a symbol or a pattern) formed on the surface of the pulp mold. From, by simply adsorbing the pulp mold on the molding surface and dehydrating,
A desired figure is provided on the surface of the pulp mold by the minute projections formed.

Further, the width of the water passage groove is preferably 0.2 to 2.0 mm on the molding surface. In this way, since the lower limit value of the width of the water passage is made sufficiently large, the adsorption rate of pulp is sufficiently fast and a sufficiently high molding efficiency is obtained, and the water generated by suction dehydration is water passed. While being efficiently discharged through the groove, the upper limit value is sufficiently small that deformation of the mesh is suppressed and the height of the convex portion formed on the pulp mold surface due to the deformation is sufficiently small. To be done.

Preferably, the suction hole has a cross-sectional area on the inner surface side of the molding die larger than that of the opening on the inner surface of the water passage groove. In this way, the cross-sectional area of the suction hole can be made sufficiently large on the inner surface side of the molding die, so that it is possible to suppress clogging due to pulp fibers or the like.

Further, preferably, the suction holes are provided at intervals of 200 mm or less in each of the plurality of water passage grooves. With this configuration, since the distance between the suction holes is sufficiently small, the suction force is less likely to be insufficient due to the pressure loss in the water passage, and a sufficiently high adsorption efficiency and dewatering efficiency can be obtained.

Preferably, the water passages are provided with a pitch of 30 mm or less, more preferably 20 mm or less. If this is done, the gap is made sufficiently small so that the reticulate body and pulp adhere to the molding surface and suction is not possible due to non-uniformity of the pulp mold thickness or the occurrence of holes, etc. The occurrence of defects is further suppressed. In order to keep the rigidity of the molding surface sufficiently high, the area of the water passage is preferably about 1/15 to 1/2 of the entire molding surface, and the pitch is preferably 2 mm or more.

[0016]

A second aspect of the present invention for achieving the above object is to provide a method for forming a pulp mold from pulp slurry. (b) A molding die having a large number of suction holes that open on the molding surface and a plurality of water passage grooves that are provided along the molding surface and that open on the inner surface of the suction holes. Soaking in the pulp sludge in a state of being covered with the body, by sucking through the suction hole, the adsorption step of adsorbing the pulp in the pulp sludge onto the mesh body, (c) outside the pulp sludge And a dehydration step of dehydrating the pulp adsorbed on the mesh body by suction through the suction hole on the molding surface.

[0017]

[Effects of the Second Invention] In this way, a molding die provided with a large number of water passage grooves provided along the molding surface and having suction holes opening to the inner surface is in a state where the molding surface is covered with a mesh body. Soaking in the pulp sludge with, and sucking through the suction holes, the adsorption process of adsorbing the pulp in the pulp sludge onto the mesh, and the suction outside the pulp sludge is adsorbed on the mesh. The pulp mold is molded by a process including a dehydration process of dehydrating the pulp on the molding surface.
Therefore, when sucked from the suction hole, that is, when the pulp in the pulp slurry is adsorbed and when the pulp is dehydrated, a large number of the suction holes are formed between the opening on the molding surface side and the mesh. A gap corresponding to the depth of the water passage will be maintained. Therefore, in the adsorption step and the dehydration step, suction is performed through the water passage,
Sufficient suction force is obtained even in the part that does not face the opening of the suction hole, the pulp is adsorbed in a sufficient thickness, and a substantially uniform pulp thickness is obtained on the entire molding surface, and only a part of a small area is obtained. It is possible to prevent the mesh body from being locally sucked and deformed, a large convex portion corresponding to the suction hole is not formed on the surface of the pulp mold, and a pulp mold having a desired surface shape can be obtained. Moreover, the gap between the opening on the molding surface side of the suction hole and the net-like body is maintained in the same manner when a fine net-like body is used. It is possible to prevent the occurrence of

[0018]

[Third Means for Solving the Problems] Further, the gist of the pulp mold of the third invention for achieving the above object is that it is molded by the method for molding a pulp mold of the second invention. There is something.

[0019]

In this way, the pulp mold is molded by the pulp mold molding method of the second invention. Therefore, a pulp mold having a desired surface shape, which has a substantially uniform thickness as a whole and does not have a large convex portion corresponding to the suction hole, can be obtained. Moreover, when a mesh having a sufficiently fine mesh is used, a pulp mold having a desired surface shape and no pulp protrusion can be obtained.

[0020]

DESCRIPTION OF THE PREFERRED EMBODIMENTS One embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a view showing the appearance of a pulp mold 10 according to an embodiment of the present invention. This mold 10
Is made of, for example, an epoxy resin, an aluminum alloy, or the like, and has a molding surface 12 having an uneven shape corresponding to the shape of the pulp mold to be molded. A large number of water passages 14 having a plurality of suction holes 18 opening on the bottom surface are, for example, 2 to 20 mm.
A net-like body 16 is fixedly provided at a predetermined center interval (pitch) and covers the entire molding surface 12 thereof.

FIG. 2 is an enlarged view showing a part of the molding surface 12 of the molding die 10. The water flow groove 14 provided in the molding surface 12 has, for example, a U-shaped cross section perpendicular to the molding surface 12, and has a width of 0.2 to 3.0 mm.
The width is preferably 1 to 5 times, preferably 1 to 2.5 times the width along the molding surface 12 in the range of 0.2 to 2.0 mm and the depth of 0.5 to 10 mm. This water channel 14
The bottom surface of the die has a diameter of 0.5 that penetrates the die 10 in the thickness direction.
Approximately 3.0mm suction hole 18 along the longitudinal direction,
The openings are opened at a predetermined interval of, for example, about 15 to 200 mm, including the relationship with the suction holes 18 provided in the peripheral water passage 14. The diameter of the suction hole 18 is ± 0.5 mm with respect to the width of the water passage groove 14 at the opening on the water passage groove 14 side.
However, the size is preferably about 0 to 0.5 mm, but as shown in the cross section along the water passage 14 in FIG. 3, on the inner surface side of the molding die 10, that is, on the back surface side of the molding surface 12, It is formed in a stepped hole shape so as to have a relatively large diameter. Further, regarding the relationship between the pitch and the width of the water flow grooves 14, it is preferable that the total area of the water flow grooves 14 be the molding surface 1.
It is set to be about 1/15 to 1/2 with respect to the whole 2.

Further, as shown in FIG. 3 above, the suction hole 1
Since 8 is inclined with respect to the molding surface 12 by a predetermined angle of, for example, about 30 °, its opening surface has an elliptical shape as shown in FIG. That is, the suction hole 18
Is provided at a predetermined angle with respect to the normal direction of the molding surface 12 along the longitudinal direction of the water passage groove 14. Further, as a general rule, the suction holes 18 are provided at intervals of 15 to 200 mm as described above, but as shown in FIG. 2, the corners that are concave with respect to the molding surface 12 are independent of the intervals. Are all provided.

Further, the suction hole 18 is provided at a portion within 20 mm from the ridge of the peripheral edge of the convex portion of the molding surface 12 excluding the ridge.
A mold-releasing purge hole 20 in the shape of an elongated hole having a diameter of 1 to 3 mm, which is slightly larger than the above, is formed. The mold release purge hole 20 is provided for facilitating the mold release by ejecting air at the time of releasing the pulp mold molded on the molding surface 12 and preventing damage at that time. It is formed mainly in the water flow groove 14, particularly when a molded pulp mold is used as a packing material, at a position where it does not hit the product. Further, the reason why it is formed on the peripheral portion of the convex portion is to suppress the deformation of the pulp mold when the mold is released. Therefore, it is not necessarily provided in all water passages 14, for example, 30 to 100 m
They are provided so that the intervals are about m. If the space is 100 mm or more, mold release failure may occur.
In the following, the man-hours will be increased without contributing to the improvement of releasability. Further, it is desirable that the air amount is larger than the suction hole 18 so that the air amount is sufficient at the time of release, but if the diameter is less than 1 mm, the air amount will be insufficient. When sucking in this way, a convex shape is generated in the pulp mold.

The reticulate body 16 fixed to the molding surface 12 is, for example, a polyester non-woven fabric having a basis weight of about ²⁰ to 50 g / m ^2.
It is attached by being adhered to the substrate with an adhesive or the like, and is prevented from being peeled off from the peripheral edge by the net-like body presser 27 fixed to the peripheral edge as shown in FIG. The reason why the non-woven fabric is doubled is to make the thickness of the mesh body 16 sufficiently thick, and for example, a polyester non-woven fabric having a basis weight of about 100 g / m ² may be fixed. In addition, in FIG. 1 and the like, the mesh body pressing member 27 is omitted.

Incidentally, FIG. 3 is a diagram schematically showing a mounting state of the molding die 10 in the pulp molding apparatus. In the figure, the chamber 23 is fixed to the tip of the support arm 22. The base 24 to which the molding die 10 is attached by the bolts 26 is fixed to the flange surface 23a of the chamber 23 by the bolts 25a and the nuts 25b. As shown in the figure, the molding die 10 has a thickness of, for example, about 2 cm and has a molding surface 1
2 has a recess 28 having a shape along 2 and the recess 28
The chamber 23 forms a closed space 30. Both the suction hole 18 and the release purge hole 20 are opened in the recess 28. Therefore, during the molding of the pulp mold, the mold release purge hole 20 also functions as a suction hole, while the suction hole 18 also functions as a mold release air ejection hole. Therefore, the size of the release purge hole 20 is limited to 3 mm or less as described above.

The closed space 30 formed by the recess 28 and the chamber 23 is connected to the switching valve 34 through the hole 32 of the support arm 22. The switching valve 34 is switched between a suction position connected to the suction pump 38 via the drain tank 36 and a jetting position connected to the compressor 40 according to the operation of a timer or the like (not shown). Therefore, according to the switching position, the suction pump 38
Due to the negative pressure in the closed space 30, the suction hole 18
The air is sucked from the air, or the air is ejected from the suction hole 18 by the compressor 40. The water stored in the drain tank 36 is appropriately discharged by a discharge pump 42.

FIG. 4 is a diagram schematically showing the overall structure of a pulp mold forming apparatus to which the mold 10 is attached. The pulp molding apparatus includes a rotation shaft 94 rotatably supported by a support device (not shown) about an axis perpendicular to the paper surface, and the rotation shaft 94 has a pair of support arms 22 (22a, 22b). ) Are mounted at rotational angle positions that differ from each other by 180 °. Those support arms 2
Molds 10a and 10b are attached to the tips of 2a and 22b, respectively. A liquid tank 98 in which pulp sludge 96 is stored is provided below the rotating shaft 94, and molding dies 10a and 10b attached to the tips of the support arms 22a and 22b respectively have a pulp sludge 9 at the lower end position.
It is designed to be dipped in 6 That is, the molding dies 10a and 10b are provided on the opposite sides of the rotary shaft 94, and are alternately positioned in the pulp slurry 96 by being rotated around the axis thereof. The pulp is adsorbed on the molding surface 12 by being sucked from the suction hole 18 while being immersed in 96.
The pulp mold 100 is formed by suction and dehydration outside the pulp slurry 96.

Above the rotary shaft 94, it is movable in the left-right direction in the drawing and vertically above the rotary shaft 94, and at the lower end position thereof, the pulp mold 100 on the molding surface 12 is provided. Release device 1 for adsorbing and transporting
02 is provided. The pulp mold 100 dehydrated on the molding surface 12 is released from the molding dies 10a and 10b by the mold releasing device 102 and sent to a drying process (not shown).

A method of molding the pulp mold 100 using the pulp mold molding apparatus configured as described above will be described with respect to one molding die 10a with reference to FIG. 4 and FIG. 5 showing the molding process. First, in the dipping step of step 1, by rotating the rotating shaft 94, the molding die 10a located on the upper side is rotated downward and the molding die 10b located on the lower side according to the arrow in FIG.
Rotate upwards. Next, in the suction step of step 2, during the rotation, the suction pump 38 is operated and the switching valve 34 connected to the molding die 10a is switched to the suction position, so that the suction hole 18 of the molding die 10a is removed. Start aspiration. The suction pump 38
Is already operated, the switching valve 34 is switched while the operation is continued.

Then, by further rotating, the molding die 10a is put into the pulp slurry 96 in the liquid tank 98, so that in the adsorption process of step 3, the pulp slurry 96 is held in the pulp slurry 96 for a predetermined adsorption time. Pulp is adsorbed on the molding surface 12. This predetermined adsorption time is set to a relatively short time, for example, about 2 seconds. When the above predetermined time has passed,
In the pulling up step of step 4, the molding die 10a is taken out of the pulp slurry while continuing the suction from the suction hole 18, and the step 5
In the dehydration step, the pulp adsorbed on the molding surface 12 is dehydrated by further continuing suction for a predetermined time of, for example, about 10 seconds to mold the pulp mold 100. Since the suction from the suction hole 18 is continuously performed, the dehydration step is executed immediately after the molding die 10a is taken out of the pulp slurry 96 in the pulling up step.

At this time, the basis weight is 100 g / m ^{2 on the} molding surface 12.
Since the mesh body 16 having a sufficiently fine mesh made of a non-woven fabric is adhered, the adsorbed pulp will not be drawn into the suction hole 18 side from the mesh body 16.
Moreover, since the molding surface 12 is provided with the water passage groove 14 and the suction hole 18 is opened to the water passage groove 14, the reticulate body 16 and the adsorbed pulp are sucked in the suction hole even during the above dehydration. 18 can not be brought into close contact with the opening on the molding surface 12 side,
In the meantime, a gap corresponding to the depth of the water passage 14 shown by h in FIG. 2 is maintained. As a result, the mesh body 16 is brought into close contact with the opening of the suction hole 18, and the suction force becomes excessive at the opening portion, while the suction force does not become insufficient in the portion other than the opening portion. Thus, a substantially uniform suction force can be obtained over the entire surface. Therefore, only a part of the reticulate body 16 and the pulp is locally sucked at the opening of the suction hole 18 to form a large convex portion on the pulp mold, and the pulp is sufficiently adsorbed at the portion separated from the opening. Insufficient thickness is suppressed. Moreover, the dehydrated water flows along the water passage groove 14 and is efficiently discharged from the suction hole 18.

After the dehydration is completed as described above, in the releasing step of step 6, the switching valve 34 is switched to the ejection position to eject the air from the suction hole 18 and the releasing purge hole 20, and at the same time, the releasing apparatus 102. By pulp mold 100
Are adsorbed on the mold 10a, released from the molding die 10a, conveyed to a drying step, and then dried by a predetermined drying device to obtain a dried product of the pulp mold 100. At this time,
As shown in the cross section of FIG. 6, a small ridge 104 having a height of 0.5 mm or less corresponding to the water passage groove 14 is formed on the surface of the pulp mold 100 (and the dried product) (the surface on the molding surface 12 side). However, a large convex portion corresponding to the suction hole 18 or a protrusion (so-called fluff) of the drawn pulp is not generated. Note that, in FIG. 6, the protrusion 104 is exaggeratedly drawn for the sake of explanation.

By the way, the molding die 10 is, for example,
It is manufactured according to the process shown in FIG. First, FIG.
As shown in (a), a master (master mold) 44 made of gypsum or wood having the shape of the molding die 10 is produced, and one surface corresponding to the molding surface 12 is machined, for example, by an end mill or sandblast. Thus, a groove 45 having the size and shape of the water flow groove 14 is formed. Silicone rubber 46 is applied to one surface of the prototype 44 on which the groove 45 is formed, and after curing, the silicone rubber 46 is removed from the prototype 44, and as shown in FIG. 48 inside 5
The duplication mold 52 having 0 is obtained.

Next, the inner surface 50 of the above-mentioned duplication mold 52.
For example, a so-called gel coat method (lamination method) in which epoxy resin is applied repeatedly with a brush to form a surface layer portion having a thickness of about 2 to 10 mm, and for backing epoxy resin (for lamination)
By coating the above resin, an epoxy resin layer 54 having a thickness of, for example, about 10 to 30 mm is formed as shown in FIG. 7 (c). At this time, the epoxy resin layer 54 is formed with a groove corresponding to the protrusion 48, that is, a water passage groove 18.
Further, as shown in FIG. 7D, for example, a reinforcing member 56, which is a plate made of FRP or the like assembled in a grid pattern, is fixed to the inner surface side of the epoxy resin layer 54 to reinforce the epoxy resin layer 54, thereby duplicating the mold 52. After removing the suction hole 18 with a drill, etc.
By forming the mold release purge hole 20, the molding die 10 is obtained. The reinforcing member 56 is omitted in FIG.

When the molding die 10 is used, it is necessary that the reticulated body 16 is attached to the molding surface 12. For example, as described above, the reticulated body 16 is made of a polyester nonwoven fabric. When the polyester non-woven fabric is heated on the molding surface 12 to a temperature of about 120 to 150 ° C., it is molded into a shape following the molding surface 12 and bonded at several places with a cyanoacrylate adhesive or the like. It is fixed on the molding surface 12.

Here, in the present embodiment, the pulp mold 10 is provided along the molding surface 12 and the suction hole 18 is opened at the bottom surface thereof, and when suction is performed from the suction hole 18, the suction hole 18 is sucked. Opening of the hole 18 on the molding surface 12 side and the mesh body 1
It is configured to include a large number of water flow grooves 14 for maintaining a gap between the water flow grooves 6. Therefore, even when the pulp is adsorbed on the molding surface 12 and when the pulp is sucked and dewatered, the depth of the water passage groove 14 is between the opening of the suction hole 18 on the molding surface 12 side and the net body 16. The gap corresponding to h (about 0.5 to 10 mm in this embodiment) is maintained. Therefore, suction is performed through the water flow groove 14, and sufficient suction force is obtained even in the portion of the suction hole 18 that does not face the opening, and the pulp is adsorbed to a sufficient thickness and molded. Surface 1
(2) A substantially uniform pulp thickness is obtained over the entire surface, and it is suppressed that only a part of a small area is locally sucked and the mesh body 16 is deformed as in the conventional case, and the pulp is sucked onto the surface of the pulp mold 100. A large convex portion corresponding to the hole 18 is not formed, and the pulp mold 100 having a desired surface shape can be obtained. In addition, the gap between the opening of the suction hole 18 on the molding surface 12 side and the net-like body 16 is maintained similarly when the fine net-like body 16 is used as in the present embodiment. It is possible to prevent the generation of pulp protrusions (fluffing) at the same time as obtaining the surface shape.

Further, according to the present embodiment, the suction hole 18 opening at the bottom surface of the water passage 14 has a predetermined angle with respect to the normal direction of the molding surface 12 along the longitudinal direction of the water passage 14. For example, it is provided so as to be inclined with respect to the molding surface 12 at about 30 °. With this configuration, the suction direction of the suction holes 18 is the direction along the longitudinal direction of the water passage groove 14, so that the mesh body 16 is further suppressed from being recessed toward the suction holes 18 and the entire molding surface 12 is covered. A more uniform suction force can be obtained, and the pulp mold 100 having a better surface shape can be obtained. Moreover, when suction dehydration is performed outside the pulp sludge 96, the water dehydrated from the pulp easily flows along the water passages 14 to accelerate the dehydration, and the dehydration rate becomes high, so that the shape retention after the mold release is maintained. Will be improved.

Further, according to the present embodiment, the water flow groove 14 has a width on the molding surface 12 of 0.2 to 2.0 mm. In this way, since the lower limit value of the width of the water passage groove 14 is made sufficiently large, the adsorption rate of pulp is sufficiently fast and sufficiently high molding efficiency is obtained, and the water generated by suction dehydration is passed through. While being efficiently discharged through the water groove 14, the upper limit value is sufficiently small, so that the deformation of the net-like body 16 is suppressed and the protrusions or ridges formed on the surface of the pulp mold 100 due to the deformation are suppressed. The height of 104 is made sufficiently small.

Further, according to this embodiment, the suction hole 18 is
The cross-sectional area of the molding die 10 on the recess 28 side, that is, on the inner surface side is made larger than the cross-sectional area of the opening on the bottom surface of the water passage 14. By doing so, the cross-sectional area of the suction hole 18 can be made sufficiently large on the inner surface side of the molding die 10,
It is possible to suppress clogging due to pulp fibers and the like.

Further, in this embodiment, the suction hole 18
Are provided at intervals of 200 mm or less in each of the plurality of water passages 14. By doing so, the gap between the suction holes 18 is made sufficiently small, so that the suction force is less likely to be insufficient due to the pressure loss in the water passage 14, and a sufficiently high adsorption efficiency and dewatering efficiency can be obtained. In this embodiment, since the suction area is determined by the water passage 14, the number of suction holes 18 should be reduced as compared with the conventional case within a range where a substantially uniform suction force can be obtained in the water passage 14. Is possible. Therefore, the number of steps for forming the minute suction holes 18 can be made simpler than in the conventional case, and the molding die 10 can be manufactured at low cost.

Further, according to this embodiment, the water passage 14 is
Since they are provided at a pitch of 20 mm or less and the distance therebetween is sufficiently small, the unevenness of the thickness of the pulp mold 100 due to the reticulate body 16 and the pulp coming into close contact with the molding surface 12 and the suction cannot be performed. The occurrence of suction defects such as the formation of holes is further suppressed. Moreover, the total area of the water passages 14 is about 1/15 to 1/2 with respect to the entire molding surface 12, and the pitch is 2 mm or more.
The rigidity of No. 2 is kept sufficiently high.

Further, in this embodiment, since the duplication mold 52 for manufacturing the molding die 10 is made of flexible silicone rubber, when the molding die 10 is manufactured and released. Even in the case of the duplication mold 52 that includes a so-called undercut shape that makes a negative angle with respect to the drawing direction, it is possible to easily release the molding die 10 by deforming the duplication mold 52 and pulling it out. Is.

Further, in this embodiment, the molding die 10 provided with a large number of water passage grooves 14 provided along the molding surface 12 and having the suction holes 18 opened on the bottom surface is used.
6 is immersed in the pulp sludge 96 in a state of being covered with 6, and sucked from the suction hole 18 to adsorb the pulp in the pulp sludge 96 onto the mesh body 16 and outside the pulp sludge 96. The pulp mold 100 is molded by a process including a dehydration process of dehydrating the pulp adsorbed on the mesh body 16 on the molding surface 12 by suction through the suction holes 18.

Therefore, when sucking through the suction hole 18,
That is, when the pulp in the pulp slurry 96 is adsorbed and when the pulp is dehydrated, a large number of water passages 14 are formed between the openings of the suction holes 18 on the molding surface 12 side and the mesh body 16. A gap corresponding to the depth h will be maintained. Therefore, in the adsorption process and the dehydration process, suction is performed through the water passage groove 14, and the suction hole 1
8 has a sufficient suction force even in the portion not facing the opening, and the pulp is adsorbed in a sufficient thickness, and a substantially uniform pulp thickness is obtained on the entire molding surface, and only a small area is locally Being restrained from being deformed by being sucked mechanically, the pulp mold 100 is suppressed.
A large convex portion corresponding to the suction hole 18 is not formed on the surface of the pulp mold 100, and the pulp mold 100 having a desired surface shape can be obtained. In addition, the gap between the opening of the suction hole 18 on the molding surface 12 side and the net-like body 16 is maintained similarly when the fine net-like body 16 is used as in the present embodiment. It is possible to prevent the generation of pulp protrusions while obtaining the surface shape.

Next, another embodiment of the present invention will be described. In the following description, the same parts as those in the above-described embodiment will be designated by the same reference numerals and the description thereof will be omitted.

FIG. 8 shows a grid-like water passage groove 58 on the molding surface 12.
It is a figure which shows the principal part of the shaping | molding die 10 provided with. The water passage 58 is formed so that its cross section perpendicular to the molding surface 12 has a V shape, and although not shown, the suction hole 18 and the mold release purge hole are provided at the V-shaped tip portion. 20 is opened. Even when such a lattice-shaped water passage groove 58 is provided, close contact between the molding surface 12 and the net-like body 16 can be avoided as in the case where the longitudinal water passage groove 14 is provided. Therefore, it is possible to obtain the same effect as that of the above-described embodiment.

The molding die 1 having the above water passage groove 58.
0 is produced as follows, for example. That is, as shown in FIG. 9 (a), for example, φ5 mm is formed on one surface 64 corresponding to the molding surface 12 of the concave mold 60 made of, for example, gypsum.
A low melting point paraffin 62 formed into a spherical shape is pressed and attached to the entire surface, cooled to a predetermined temperature of, for example, about 18 ° C. to be cured, and then released to prepare a prototype. At this time, as shown in FIG. 9 (b), which is a cross section of the main part of the master 68 before release, the one surface 64 side of the spherical paraffin 62 attached to the concave mold 60 is the one surface 64 as a whole.
At the same time, the curved surface 65 on the one surface 64 side of the spherical paraffin 62 remains after being attached, so that the curved surface 65 is formed on the molding surface on the one surface 64 side of the prototype 68. A groove 66 having a V-shaped cross section, that is, a grid-shaped groove corresponding to the grid-shaped water passage groove 58 is formed. That is, in the present embodiment, spherical paraffin 62 is used instead of forming a groove in the prototype by machining or the like.
By attaching the mold to the concave mold 60 and releasing the mold 6
At the same time that 8 is manufactured, lattice-shaped grooves are formed in the prototype 68.

After the master 68 is formed as described above, the mold 10 is formed in the same manner as the embodiment shown in FIG.
Is obtained. Therefore, the molding surface 1 of the obtained molding die 10
As described above, the water passages 58 having a V-shaped cross section perpendicular to the molding surface 12 are formed in the grid 2 in the shape of a grid. As shown in this embodiment, the cross sectional shape of the water passage is U
The shape of the groove is not limited to the V shape, and may be various shapes such as a V shape. Further, the method for forming the groove of the prototype is not limited to machining.
It is also possible to use a method such as attaching the spherical paraffin 62 to the concave mold 60 as described above. In addition, in the case of the present embodiment, there is an advantage that it is not necessary to form a groove in the master 68.

In the process of manufacturing the prototype 68, as shown in FIGS. 9A and 9B, the bottom corner portion 7 of the concave mold 60 is formed.
When the radius of curvature of 0 is small, the shape cannot be accurately transferred by directly attaching the spherical paraffin 62. Therefore, when using the concave mold 60 having the bottom corner 70 having such a small radius of curvature, for example, as shown in FIG.
It is preferable to attach the paraffin 62 first and then attach the spherical paraffin 62 as described above.

FIG. 11 is a view showing still another embodiment, in which a master mold for manufacturing a mold having striped water passage grooves 14 similar to the mold 10 shown in FIG. 1 is prepared. The other method will be described. First, the protrusion 4 is formed by inverting the molding die 10 with gypsum or the like, that is, having the same inner surface shape as the duplication die 52 made of silicone rubber.
A concave mold 74 having no 8 is manufactured. Then, the concave mold 7
The entire surface of one surface 75 corresponding to the molding surface 12 of
2 to φ8 mm rod-shaped thermosetting clay (for example,
Epoxy resin type clay etc.) 76 is pressed, and as shown in an enlarged view in FIG. 12, it is incompletely crushed and stuck so that the deformation rate Δd / D is about 0 to 40%. In the figure, the broken line represents the cross-sectional shape of the thermosetting clay 76 before deformation. Then, by heating this at a predetermined temperature to cure the thermosetting clay 76, the mold is released to obtain the above prototype. At this time, if releasing is difficult, a backing material for gel coat (for example, epoxy resin mixed with glass cloth or glass fiber)
After strengthening with etc., it is good to release.

Even with the above arrangement, the structure shown in FIGS.
In the same manner as the example shown in (1), a curved surface 78 remains on the attached thermosetting clay 76, and the pair of curved surfaces 78, 78 of the adjoining thermosetting clay 76 causes A groove 80 having a V-shaped cross section is formed on one surface corresponding to the molding surface 12.

FIG. 13 shows a pulp mold 10 to be molded.
It is a figure which shows the principal part of the shaping | molding surface 82 of a shaping | molding die for forming a figure, such as a predetermined symbol and a pattern, on the surface of 0. In the figure, a water passage groove 84 is formed on the molding surface 82, and a part of the water passage groove 84 is formed, for example, in the pulp mold 100.
Of the product number (A112-R in the figure) is the figure water passage groove portion 85 provided in an inverted shape, and several suction holes 18 are provided in the independent water passage groove 84 that constitutes each character. Is open. Molded pulp mold 10 as described in the embodiment shown in FIG.
On the surface of 0, minute protrusions 1 having a shape corresponding to the water flow groove 84
04 is formed, the pulp mold 100
The product number and the like are formed in a convex shape on the surface of the.

That is, in this embodiment, the water passage 8
By appropriately setting the planar shape of No. 4, the molding surface 82
A groove for pattern formation is separately provided in the pulp mold, or the pulp mold 100 is pressed from both sides for the purpose of improving the surface accuracy of the mold after so-called after-pressing. It is possible to form a figure such as a product number on the surface of the mold 100. In the figure, the suction holes 18 in the stripe-shaped water passage grooves 84 are omitted.

14 (a) and 14 (b) are water passage grooves 86, 88 which are still another example of the shape of the water passage groove provided on the molding surface 12.
It is a figure which shows the cross-sectional shape perpendicular | vertical to the shaping surface 12 of FIG. FIG.
In FIG. 11A, the water passage groove 86 is provided in a step shape, and in FIG. 11B, the water passage groove 88 is provided in a sawtooth shape. These water passage grooves 86, 88 do not have a definite groove shape, but the virtual forming surface 9 shown by the one-dot chain line in the figure.
0 (that is, the molding surface formed by the mesh body 16) forms a gap 92, which serves to guide water to the suction hole 18 during suction dehydration. Even the water passage grooves 86 and 88 having such a shape have the same effects as the water passage groove 14 and the like.

That is, in the present invention, the "water passage" means a gap between the opening of the suction hole 18 on the molding surface 12 side and the mesh body 16 when the molding surface 12 and the mesh body 16 are in close contact with each other. The shape is not particularly limited as long as it can maintain and secure a sufficient suction area and a flow path of water generated by dehydration, and that substantially fulfills the function of the water passage groove.

Although one embodiment of the present invention has been described in detail with reference to the drawings, the present invention can be carried out in still another mode.

For example, in the above-described embodiment, the water flow grooves 14 and the like are provided on the molding surface 12 and the like in a stripe shape or a lattice shape, but a substantially uniform suction force is obtained on the entire molding surface 12 and the like. If it is provided, for example, it may be provided in a curved shape. Therefore, as in the embodiment shown in FIG. 12, the pattern is formed on the surface of the pulp mold 100 so as to form a predetermined figure, and in addition to the pattern being inverted, the appearance is enhanced or the cushioning action is enhanced. The water flow groove 14 and the like may be formed by various curved lines and the like so that various patterns such as swords are formed.

Further, in the embodiment, by machining or pasting paraffin or thermosetting clay, etc.,
Grooves corresponding to the water flow grooves 14 and the like are formed on the prototype 44 and the like,
For example, the groove may be formed on the master mold 44 or the like with a marking needle or the like. When the groove is formed by the sticking method, not only paraffin and thermosetting clay but also various thermoplastic resins and thermosetting resins can be used.

Although the mold 10 and the like are made of epoxy resin in the examples, metals such as aluminum and its alloys and stainless steel, other resins such as urethane and silicone, gypsum or plaster surface are coated with resin or chemically. It may be composed of a plated material, a wood material or a wood material similarly coated on the surface thereof.

Further, in the embodiment, a groove corresponding to the water passage groove 14 etc. is formed in the master mold 44 etc. and silicone rubber is applied to the master mold 44 etc. to make a replica mold 52, and the replica mold 52 is produced. Although the water-permeable groove 14 and the like were formed at the same time as forming the molding die 10 made of epoxy resin from the working die 52 by gel coating, for example, the water-permeable groove 14 and the like were directly formed on the molding die 10 and the like by etching or machining. You may. For example, when the molding die 10 or the like is made of aluminum casting or the like, the water passage groove 1 of the molding die 10 or the like is used.
It is also possible to form the water flow grooves 14 and the like by coating the portions where the 4 and the like are not formed with resin or plating and chemically etching using a corrosive agent such as caustic soda.
When the molding die 10 or the like is made of gypsum, wood, resin, or the like, it is possible to directly form the water flow grooves 14 or the like in them by machining or the like.

Further, in the above-mentioned embodiment, the molding die 1 is used.
0 and the like were made of epoxy resin, but the replication mold 5
The molding die 10 and the like may be manufactured by gel-coating an inner surface corresponding to the second molding surface 12 with another thermosetting resin such as phenol resin.

In addition, in the embodiment, the mold 10 is provided with the mold release purge hole 20 in addition to the suction hole 18, but if the mold release is possible only by the suction hole 18, the mold release purge is carried out. The hole 20 does not necessarily have to be provided.

Further, in the embodiment, all the suction holes 18 are provided so as to be opened at the bottom surface of the water passage groove 14, but they may be provided so as to be opened at the side surface, for example. Furthermore, a part of the suction hole 18 may be provided in a portion other than the water passage groove 14 on the molding surface 12.

Further, in the embodiment, the suction hole 18 is formed as a stepped hole in which the area of the opening on the inner surface side of the molding die 10 is larger than the area of the opening on the water passage groove 14 side. It may be formed in a conical shape whose cross-sectional area gradually increases from the groove 14 side toward the inner surface of the molding die 10. If clogging is unlikely to occur, the entire structure may have the same cross-sectional area.

In the embodiment, a non-woven fabric made of polyester is used as the mesh body 16. However, for example, another non-woven fabric such as polyester or polypropylene or tricot, a mesh made of resin, stainless steel or brass is used. Etc. may be used. In addition, when a mesh is used, the effect of suppressing pulp protrusions (fluffing) can be obtained with # 40 to # 400 (wire diameter 0.03 to 0.22 mm).
Since the wire diameter of the mesh is preferably 0.01 mm or more from the viewpoint of durability, it is preferable to use a mesh having a mesh opening coarser than about # 100, for example, a mesh of about # 80.

Although not specifically exemplified, the present invention is
Various changes can be made without departing from the spirit of the invention.

[Brief description of the drawings]

FIG. 1 is a diagram showing an entire pulp mold of a first embodiment of the present invention.

FIG. 2 is an enlarged view showing a part of a molding surface of the molding die of FIG.

FIG. 3 is a view showing an attached state of the molding die of the molding die of FIG. 1 in a pulp molding apparatus, in a cross section taken along a water passage.

FIG. 4 is a diagram schematically showing a configuration of a pulp mold molding apparatus in which the molding die of FIG. 1 is used.

5A and 5B are process diagrams illustrating a pulp mold forming method by the pulp mold forming apparatus in FIG.

6 is a diagram showing a cross-sectional structure of a pulp mold obtained by the process of FIG.

FIG. 7 is a diagram illustrating a manufacturing process of the molding die of FIG. 1.

FIG. 8 is a view showing a main part of a molding die according to another embodiment of the present invention.

9 (a) and 9 (b) are views for explaining a method of manufacturing the molding die of FIG.

FIG. 10 is a diagram illustrating a method of processing a concave bottom corner portion in the manufacturing method of FIG. 9;

FIG. 11 is a view for explaining another example of the method for manufacturing the mold having the stripe-shaped water passage grooves.

FIG. 12 is a view showing a cross section of thermosetting clay that is stuck in a concave shape in the manufacturing method of FIG. 11.

FIG. 13 is a diagram showing another example of the planar shape of the water passage groove.

14 (a) and 14 (b) are diagrams showing another example of the shape of a water passage groove.

[Explanation of symbols]

 10: Molding die 12: Molding surface 14: Water passage groove 16: Net body 18: Suction hole 96: Pulp slurry 100: Pulp mold

Front Page Continuation (72) Inventor Fumitaka Miwa 3-36 Noritake Shinmachi, Nishi-ku, Nagoya, Aichi Prefecture Noritake Company Limited 3-36 Noritake Company Limited Limited

Claims (5)

[Claims] 1. A large number of suction holes opened on a molding surface,
Suction from the suction hole in a state in which the molding surface is covered with a mesh, while adsorbing the pulp in the pulp slurry on the mesh in the pulp slurry, the adsorbed pulp outside the pulp slurry. A mold of a pulp mold for forming a pulp mold by dehydrating on the molding surface, the suction hole being provided along the molding surface, the suction hole opening to the inner surface, and suction from the suction hole. A molding die for pulp mold, comprising a plurality of water passage grooves for maintaining a gap between the opening of the suction hole on the side of the molding surface and the mesh body when subjected to a pressure treatment. 2. The suction hole opening on the inner surface of the water passage is provided so as to be inclined at a predetermined angle along the longitudinal direction of the water passage with respect to the normal direction of the molding surface. A mold for a pulp mold according to claim 1. 3. The mold for a pulp mold according to claim 1, wherein at least a part of the water passage is provided in a pattern corresponding to a predetermined figure formed in a convex shape on the surface of the pulp mold. 4. A method for molding a pulp mold from pulp slurry, comprising a number of suction holes opening on a molding surface, and a plurality of passages provided along the molding surface, the suction holes opening on an inner surface thereof. A molding die having a water groove is immersed in the pulp slurry in a state where the molding surface is covered with a mesh, and suction is carried out from the suction hole to remove the pulp in the pulp slurry onto the mesh. And a dewatering step of dewatering the pulp adsorbed on the reticulated body on the molding surface by sucking from the suction hole outside the pulp sludge. Mold forming method. 5. A pulp mold formed by the method for forming a pulp mold according to claim 4.