JPH10194345A - Pulp-molded body and production thereof - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a pulp-molded body and the production thereof, by protecting the surface of the pulp-molded body with paper, plastic sheets, etc., to increase the strength of the surface and prevent paper powder from peeling out of the surface. SOLUTION: A paste is made from a starchy binder by adding water into a pulp-molding material containing pulp as a main raw material and the starchy binder and thermoexpansive hollow particles and heating the mixture at a higher temperature than a specified one to combine the pulp and the thermally- expansive hollow particles and form the pulp-molded body. Sheet members 9a, 9b are stuck on a part or the whole of the surface of the pulp-molded body.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

[0001] The present invention relates to a pulp mold material having a buffering property formed by using a pulp as a main material and a pulp mold material containing a starch-based binder and thermally expandable hollow particles. The present invention relates to a bonded pulp molded article and a method for producing the same.

[0002]

2. Description of the Related Art Styrofoam is conventionally used for packaging materials for electrical equipment such as televisions, video tape recorders, cassette tape recorders, etc., food trays for vegetables and fruits, and fish boxes for seafood and the like. Styrofoam molded articles are used. Since this polystyrene foam is lightweight, has relatively high strength and is excellent as a cushioning material, it is used in a large amount in a packaging material for electric equipment and the like.

As described above, the styrofoam molded article is an excellent cushioning material, but on the other hand, causes various problems in disposal after use. For example, when styrene foam is incinerated, high heat is generated during combustion, which damages the incinerator. Further, when styrofoam is directly embedded in soil, the styrofoam is not decomposed in soil and remains as it is without being soiled. As described above, since the styrofoam molded article has many problems in its disposal method, the use of a large amount of the styrofoam molded article has become an issue with the growing momentum for environmental protection and resource saving on a global scale.

[0004] In recent years, in view of such environmental problems and effective use of resources, there has been a demand for the development of molding materials such as non-polluting and resource-saving packaging materials as alternatives to Styrofoam. As one of them, conversion to a pulp molding material using waste paper such as newsprint as a main raw material is progressing.

[0005] As a molded article made of this pulp mold material, for example, a pulp mold slurry obtained from waste paper such as newsprint is adsorbed on a porous or netted mold and subjected to several stages of dehydration, pressing and drying processes. What is molded is known.

[0006]

However, in a pulp molded article as a molded article of the pulp molding material molded in this way, paper powder generated by pressing or die cutting after molding adheres to the surface. Therefore, when used as a cushioning material for a buffered object such as a television, a video tape recorder, and an audio device, when an external force such as vibration is applied from the buffered object with which the material comes into contact, the surface of the pulp molded article is removed. There was a problem that the paper powder peeled off.

Further, the pulp molding material has a specific gravity about 5 times that of the expanded polystyrene (for example, the mass of a 50-fold expanded polystyrene is about 0.02 g / cm ³ , while the mass of the pulp molding material is about 5 times. 0.08-0.14
g / cm ³ . Therefore, when used as a cushioning material, since it appears as the weight of the package to be buffered, there has been a problem that the transport weight is increased.

The present invention has been made in view of the above problems, and protects the surface of a pulp mold body with paper, a plastic sheet, or the like, increases the strength of the surface, and reduces paper dust from the surface. It is an object of the present invention to provide a pulp molded article that does not peel off and a method for producing the same.

[0009]

Means for Solving the Problems In order to solve the above-mentioned problems and achieve the above objects, a pulp molded article of the present invention comprises a pulp as a main raw material and a starch-based binder and heat-expandable hollow particles. By adding water to the pulp mold material containing the pulp and heating it to a predetermined temperature or more, the starch-based binder is gelatinized, and the pulp and the thermally expandable hollow particles are combined to form a pulp mold body. It is characterized in that a surface protection member is adhered to a part or the whole of the body surface.

[0010] The method for producing a pulp molded article of the present invention is characterized in that a pulp molding material containing pulp as a main raw material and a starch-based binder and heat-expandable hollow particles is used to form a starch-based binder. The pulp mold material to which water has been added is filled into a mold, and the filled pulp mold material is heated to a temperature at which the starch-based binder is gelatinized to gelatinize the starch binder to form a pulp mold body. It is characterized in that a surface protection member is adhered to a part or the whole of the surface of the pulp mold.

With the above-described structure, in the pulp molded article of the present invention, the surface protection member is adhered to the portion of the pulp molded body that comes into contact with the buffered object. Even when an external force such as vibration is input from the pulp, no troubles such as breakage of the contact portion and peeling of paper powder from the surface of the pulp mold material do not occur. Further, according to the method for producing a pulp molded article of the present invention, the pulp molded article can be produced efficiently and at low cost.

[0012]

Embodiments of the present invention will be described below with reference to the drawings. FIGS. 1 to 6 show a first embodiment of the present invention, in which a pulp molded article in which a surface protection member is adhered to a part of the surface of a pulp molded article, a molding die used in a method for producing the pulp molded article, It is a figure showing a compression device and a shaping device. 7 to 15 show a second embodiment of the present invention, in which a molding die for integrally molding a pulp molded body at a plurality of required positions of a base member, a manufacturing method thereof,
It is a figure showing a pulp molded object and its use state. 16 to 20 show a third embodiment of the present invention, in which another example of a molding die for integrally molding a pulp molded body at a plurality of required positions of a base member and a pulp molded body thereof FIG.

In the embodiment described below, a specific example of a pulp molded product is applied to a cushioning material for an electric device or the like, and a molding die for molding the cushioning material and a method for manufacturing the same will be described as examples. .

As shown in FIG. 1, a pulp molded article 1 as a cushioning material according to a first embodiment of the present invention.
Is formed by bonding a surface protection member to a part of the surface of a pulp mold body formed by hardening a pulp mold material. This pulp mold material is
Pulp is used as a main raw material and contains a starch-based binder and thermally expandable hollow particles.

The pulp molded article 1 has a substantially rectangular flat surface portion 1a, a bank portion 1b provided on one side edge of the flat surface portion 1a, and an upright wall portion provided on the opposite side of the bank portion 1b. 1c, and a side wall 1d extending from both ends of the upright wall 1c to the bank 1b side. A square notch 1e is formed at the upper center of the upright wall 1c. A surface protection sheet 9a showing one specific example of a surface protection member is provided on each surface of the flat portion 1a and the bank portion 1b of the pulp molded article 1.
And 9b are respectively adhered.

The pulp as a main raw material of the pulp molded article 1 is formed, for example, as follows. That is, newsprint was pulverized for 10 minutes with a fibrillator (HFC-23: manufactured by Orient Co., Ltd.), and a pulp fibrillated product was obtained through a filter having a diameter of 2.5 mm. The pulp defibrated material is mainly formed by mixing a small piece of paper having a size of about 2 mm square and a defibrated pulp. In this case, the pulverization is stopped before the whole is in a flocculent state in a state in which the flocculent fiber is larger than the small paper pieces.
By using a mixture of this flocculently defibrated material and a small piece of paper, it is easier to uniformly contain moisture than when only the flocculently defibrated material is used. Gelatinization is performed uniformly.

The pulp defibrated material contains 50% by weight of moisture, 3% by weight of expanded thermally expandable hollow particles (f-80D: manufactured by Matsumoto Yushi Seiyaku Co., Ltd.), and modified starch (EAT-4; acetylation degree: 3%). 10% by weight) and kneaded with a planetary mixer for 5 minutes to obtain a pulp mold material. In this pulp molding material, newspaper waste paper as a main raw material contains about 9% of water in an air-dried state, so that the total water content is over 36%.

Further, the heat-expandable hollow particles serve as a cushion in a cushioning material as a pulp mold formed by a molding apparatus described later. That is, when the cushioning material is pressed from the outside, the hollow particles are deformed and have a function of increasing the cushioning effect. As the thermally expandable hollow particles, the outer shell polymer covers the inner shell hydrocarbon, and the outer shell polymer is softened by heating, and the inner shell hydrocarbon is gasified to expand the volume several tens times. Heating these particles (heat-expandable microcapsules) into hollow particles can be used.

As such heat-expandable hollow particles, those having an outer shell having excellent elasticity to absorb stress well, having a heat deformation temperature of 130 ° C. or more, and having good heat resistance should be used. Is desirable. More specifically, for example, the boiling point of isobutane, pentane, petroleum ether, hexane, etc. is 5
A heat-expandable microcapsule (particle size distribution: 10 to 30 μm) obtained by enclosing an organic solvent at 0 ° C. to 100 ° C. with a thermoplastic resin composed of vinylidene chloride, acrylonitrile, acrylate, methacrylate, etc.
Heat to 50 ° C for a short time to increase the diameter by 4 to 5 times and the volume by 50 to
Hollow particles expanded 100 times and elastically deformed (true specific gravity 0.015 to 0.025, particle size distribution 40 to 20)
0 μm, average particle size 100 μm or less, pressure resistance 300 kg /
cm ² or more) can be used.

When such a heat-expandable microcapsule is used for producing a pulp molded article made of the pulp molding material of the present invention, it may be expanded in advance before mixing with the pulp to form hollow particles. And then expanded to form hollow particles.

In each of the embodiments described below, the heat-expandable hollow particles which have been expanded in advance are mixed into the pulp defibrated material. However, from the viewpoint of cost, it is more advantageous to expand the heat-expandable hollow particles after kneading them with the modified starch and water in the pulp defibrated material. When expanding after the kneading, it must be ensured that the hollow particles can expand sufficiently. The blending amount of the heat-expandable hollow particles can be appropriately determined according to the type of pulp to be used and the like, and the mixing ratio is determined in relation to a modified starch functioning as a binder described later.

For example, when the mixing ratio of the heat-expandable hollow particles is increased, the cushion function can be increased, but the cost increases. On the other hand, by reducing the mixing ratio of the heat-expandable hollow particles and increasing the added amount of the modified starch, it is possible to reduce the cost and increase the bonding force between the pulp defibrated material and the hollow particles. it can. Further, starch used as a binder has a part of hydroxyl groups in its molecule modified.

This modified starch is preferably one in which a part of the hydroxyl groups in the starch molecule has been substituted with an acetyl group or an ester group, has a low gelatinization temperature and is about 55 ° C. to 65 ° C. . Increasing the amount of the modified starch increases
Since the hardness of the cushioning material as a pulp molded article becomes harder, the cushioning effect decreases, and conversely, if the amount added is small, the strength of the cushioning material itself decreases. Therefore, the upper limit of the amount of modified starch to be added is how much the buffering effect is,
And the cost, and the lower limit is determined by the strength of the cushioning material itself.

The surface protection sheets 9a, 9b described above
For example, various sheet members such as paper and plastic sheets can be applied. These papers and plastic sheets need to be provided with sufficient ventilation and water permeability to allow the passage of water vapor during pulp molding. Here, "aeration and water permeability sufficient to allow water vapor to pass" means that the paper, plastic sheet, and the like are in the following state. The first is that if the gap between the fibers of paper or the like is large and it has sufficient air permeability and water permeability, the second is to provide a hole of a suitable size and number in paper or a plastic sheet, etc. This is the case where sufficient air permeability and water permeability are ensured by the holes. When this second hole is provided, the ventilation and water permeability can be freely adjusted by appropriately setting the diameter and the number of the holes.

The waste paper forming pulp as the main raw material is not limited to newspaper waste paper, but may be cardboard waste paper or other paper. Then, these waste papers can be shredded into strips or milled until they become cotton-like to prepare and use pulp defibrated materials.

Next, the pulp molding material 1 obtained as described above is used to mold the pulp molded article 1 as a cushioning material.
Will be described with reference to FIGS.

As shown in FIGS. 2 to 4, a mold 2 as a molding die includes, for example, a lower mold 3 having an upper surface serving as a main molding portion having a predetermined uneven shape, and a plate-like shape serving as a pressing portion. Upper mold 4
And a box-shaped frame 5 having upper and lower surfaces in which the lower mold 3 and the upper mold 4 are inserted. A large number of ventilation holes 3a, 4a and 5a are formed in the lower mold 3, the upper mold 4 and the frame 5, respectively, with a hole diameter of 6 mm and a pitch between adjacent holes of 15 mm, for example. . Steam supplied from a steam heating and molding apparatus described later passes through these vents 3a, 4a and 5a.

On both sides of the upper surface of the upper die 4, guide / fixing pieces 6 for the frame 5 are respectively provided upright. Each guide / fixing piece 6 is formed with a guide elongated hole 6a extending vertically. This guide slot 6a
The upper die 4 is inserted into the screw hole of the frame 5 so that the upper die 4 is
To be fixed. A flange 5b that protrudes outward is provided at a peripheral edge of an upper end of the frame 5. A pair of grips 8 facing each other are attached to both sides of the upper surface of the flange 5b.

As shown in FIG. 4, the compression device 10 has an air cylinder 12 installed in an upper half 11a of a machine frame base 11,
The lower half portion 11b is provided with a mold accommodating portion 13. At the lower end of the cylinder rod 12 a of the air cylinder 12, a pressing plate 14 that is inserted into the frame 5 of the mold 2 by pressurized sliding of the cylinder rod 12 a downward is attached. The pressing plate 14 is provided with a number of holes 14a through which water passes. Further, the mold accommodating portion 13 includes
A mold holding member 15 for holding the mold 2 from both sides is provided.

As shown in FIG. 5, in a steam heating and forming apparatus 17 which is a specific example of the heating and forming apparatus, a main body 18 and a mold accommodating chamber 19 are arranged continuously with the mold accommodating chamber 19 vertically interposed therebetween. An upper exhaust chamber 20 and a lower pressure regulating chamber 21,
It is held by the machine frame 22. This type accommodation room 19
The front wall portion can be opened and closed, and the exhaust chamber 20 formed in the shape of a truncated pyramid can be lifted up and opened with the rear end side of the mold accommodating chamber 19 as a fulcrum. The configuration is such that the work of attaching and detaching the mold 2 to and from the accommodation room 19 can be easily performed.

The mold accommodating chamber 19 and the pressure regulating chamber 21 are vertically divided by a mold support plate 23. The mold support plate 23 has a large number of ventilation holes, for example, a hole diameter of 6 m.
m, the holes are drilled at a pitch of 15 mm between adjacent holes, so that a sufficient amount of water vapor can be passed. A cavity 24 for fitting and holding the mold 2 is installed in the mold support plate 23 so as to communicate with the lower pressure regulating chamber 21. An opening 25 into which the frame 5 of the mold 2 is inserted is formed in the mold mounting surface 24 a on the upper surface side of the cavity 24. A toggle clamp 26 for fastening the frame 5 of the mold 2 at the flange 5b is attached to a surface surrounding the opening 25. The pressure regulating chamber 21 is formed in the shape of an inverted truncated pyramid, and has a water droplet prevention net 2 inside thereof.
7 is stretched.

Each pipe is connected to the main body 18 of the steam heating and forming apparatus 17 configured as described above. Therefore, an exhaust port 28 is provided in the upper surface portion 20 a of the exhaust chamber 20, and first and second air supply ports 29 and 30 with a valve and an exhaust port 31 with a valve are provided in the bottom surface 21 a of the pressure regulating chamber 21. It is attached. An exhaust pipe 32 is connected to an exhaust port 28 of the exhaust chamber 20. A first pipe 33 for pressurized steam supply is connected to a first valve supply port 29 of the pressure regulating chamber 21, and a room temperature pressurized air supply is connected to a second valve supply port 30. Second piping 34 is connected. A drain pipe 35 for drainage is provided in the drain port 31 with a valve.
Are connected.

The exhaust pipe 32 is connected to a blower 36 for sucking air inside the main body 18 and discharging the air to the outside. The first pipe 33 is connected to a boiler 38 for generating pressurized steam via a switching valve 37, and a drain pipe 40 is connected to a middle part of the first pipe 33 via a drain valve 39. I have. Further, the second pipe 34 is connected to the compressor 41, and the drain pipe 35 is led to a drain.

The thus configured mold 2 and compression device 1
Next, the step of molding the pulp molded article 1 using the pulp molding material described above using the steam heating apparatus 17 and the steam heating molding apparatus 17 will be described.

As shown in FIG. 2 and FIG.
The lower die 3 is fitted to the lower end of the frame 5 of the above. The upper surface of the lower die 3 has a hole or the like through which a sufficient amount of water vapor can pass at the time of pulp molding. Lay excellent surface protection sheets 9a and 9b. The pulp molding material P described above is placed on the surface protection sheets 9a and 9b.
M is charged in a predetermined amount, and is pressed and filled so as to spread over the entire upper surface side of the uneven shape of the lower mold 3. After the filling of the pulp molding material, the upper mold 4 is inserted through the upper opening of the frame 5 and placed on the pulp molding material PM. In this state, upper mold 4
The fastening screw member 7 with a handle is inserted into the guide slot 6a of the guide / fixing piece 6 on both sides of the upper surface of the upper die 4.
To the extent that can slide.

The mold 2 filled with the pulp mold material PM is accommodated in the mold accommodating portion 13 of the compression device 10, and the mold 2 is squeezed and held by the mold holding member 15 from both sides. 10 is set at a predetermined position. In this state,
By operating the air cylinder 12, the cylinder rod 12a is projected downward. The pressing plate 14 is moved downward by the protrusion of the cylinder rod 12 a, and as a result, the pressing plate 14 is inserted into the frame 5 of the mold 2 and pressed against the upper surface of the upper die 4. Further, the upper die 4 is pressed by the pressing plate 14 by operating the cylinder rod 12a, and the pulp molding material PM in the die 2 is compressed at a predetermined pressure.

Thus, the pulp molding material PM is
For example, the density after drying is 0.125 g / cm ³ (125
kg / m ³ ), and formed into a shape along the concave and convex shape of the lower mold 3. In this state, the tightening screw member 7 with the handle is tightened, and the upper die 4 is fixed to the guide / fixing piece 6.
And is fixed to the frame body 5 via. After this, the air cylinder 12
The cylinder rod 12a is raised by the returning operation,
The mold 2 is taken out of the mold accommodating portion 13 of the compression device 10 and transported to the steam heating and molding device 17. Then, the pulp molding material P in the mold 2 is
The molded body of M is combined and dried to form a pulp molded body 1 having a predetermined shape.

In the steam heating and forming apparatus 17, first,
The mold 2 is housed in the mold housing chamber 19. This housing is performed by opening the front wall portion of the mold housing room 19 and jumping up the exhaust chamber 20, and the mold mounting surface portion 2 of the cavity portion 24 in the mold housing room 19.
4a and the opening 25 are exposed. The mold 2 is inserted into the opening 25, and the flange 5 b of the frame 5 is attached to the mold mounting surface 2.
4 a, and is clamped and fixed by the toggle clamp 26. Thereafter, the front wall is closed and the exhaust chamber 20 is closed.
Is closed, and the mold accommodating chamber 19 is sealed.

In this state, the first pipe 33 on the pressure regulating chamber 21 side
Is opened, and the boiler 38 is driven to generate pressurized steam. This pressurized steam has a pressure of approximately 1 atm.
The pressure is set to 100 ° C. to 110 ° C. when converted to heat at 5 atm, and the air is sent from the first valved air supply port 29 to the pressure regulating chamber 21 through the first pipe 33. This pressure regulating chamber 21
Inside, the water droplets of the pressurized steam are removed by the water droplet prevention net 27, and the pressure is equalized so that the mold accommodating chamber 1
9 is supplied into the cavity 24.

At this time, if the pressure of the steam is too high, the heat-expandable hollow particles of the pulp molding material PM are deformed or cracked. Conversely, if the pressure of the steam is too low, the modified starch will not be sufficiently gelatinized. The water droplets condensed in the pressure regulating chamber 21 are drained from a drain port 31 with a valve through a drain pipe 35, and the water droplets condensed in the first pipe 33 are drained from a drain pipe 40 by opening a drain valve 39. .

In this manner, by closing the valve of the drain port 31 and the drain valve 39 in a state where the dew condensation in the pressure regulating chamber 21 and the first pipe 33 is eliminated, the steam is removed from the cavity of the mold accommodating chamber 19. 24, the pulp molding material PM in the mold 2 is supplied. At this time, the water vapor in the cavity 24 is supplied to the lower mold 3 of the mold 2 and the ventilation holes 3 a and 5 of the frame 5.
a into the mold 2 through the pulp mold material PM
Passes through the ventilation hole 4 a of the upper mold 4 and reaches the exhaust chamber 20 above the mold accommodating chamber 19.

When the heated steam passes through the mold 2,
By supplying heat and moisture to the pulp mold material PM, the modified starch is gelatinized. After that, steam is exhausted into the exhaust chamber 2
For example, the exhaust gas is forcibly exhausted at a negative pressure of about 0.5 atm by the exhaust fan 36 from the exhaust port 28 of the upper surface 20a of the zero through the exhaust pipe 32. Thus, the pulp mold material PM is heated while being added with water by the steam supplied from the lower part of the mold 2 and passing through the pulp mold material PM.

The supply of the steam and the forced evacuation continue for a required time (for example, several tens of seconds), and the first valved air supply port 29 is closed and the second valved air supply port is used together with the forced exhaust. 30 and open the compressor 4 from the second pipe 34.
A gas at a temperature lower than the gelatinization temperature of the modified starch as a binder at a predetermined pressure generated by the step 1, for example, a dry room temperature air of about 1.4 atm is blown into the pressure regulating chamber 21 and the blowing is continued for several tens of seconds. I do. After the completion of the blowing and the forced exhaust, the mold accommodating chamber 19 is opened, and the mold 2 is taken out from the steam heating and forming apparatus 17. Then, the mold 2 is disassembled, and the molded body of the pulp mold material PM is released from the mold 2.

Thus, the pulp molding material PM in the mold 2 is steam-heated in the main body 18 of the steam heating and molding apparatus 17, during which the modified starch added as a binder is gelatinized. After the steam heating, the pulp molding material PM is held in the mold 2 taken out of the steam heating molding device 17, and the gelatinization of the modified starch proceeds by the heat applied by the steam, Evaporation of the water content of the gelatinized starch increases the binding strength of the starch. As a result, the hardness of the pulp molded article becomes sufficiently hard to maintain the original shape against the resistance force when the mold is released from the mold 2.

Then, the pulp molded product released from the mold is dried by a dryer, and subjected to secondary drying until the moisture content of the pulp molding material PM becomes about 15% or less. Thereby, a pulp molded article as the cushioning material 1 in which the surface of a necessary portion is protected by the surface protection sheets 9a and 9b is obtained. According to the pulp molded article 1, when used as the cushioning material 1, even if it is subjected to vibration or external force due to contact with an object to be buffered, the surface protection sheet 9a,
9b prevents the pulp mold material PM from being destroyed, and effectively prevents the paper powder from peeling off from the surface of the molded body.

In the heat molding method using steam according to the first embodiment, heat and moisture are supplied to the pulp mold material PM when passing through the pulp mold material PM. Has a water content of 20
It may be up to 60% by weight. The lower limit of 20% by weight of the water content is an amount necessary to easily knead the flocculence of a piece of paper and the thermally expandable hollow particles and modified starch. However, although the amount of water necessary for gelatinizing the modified starch is slightly insufficient, the insufficient amount is compensated for by the heated steam. The upper limit of 60% by weight of the water content is determined by the drying time and releasability of the molded article.

In this embodiment, the compression device 10
Although the example in which the steam heating and forming apparatus 17 is provided separately from the steam heating and forming apparatus 17 has been described, the two apparatuses 10 and 17 may be integrated into one steam heating and compression forming apparatus. For example, there is a case where the compression device 10 is provided as it is in the mold storage chamber 19 of the steam heating and forming device 17 described above.
In this case, since the heating steam can be supplied simultaneously while compressing the pulp molding material PM, the production efficiency of the pulp molding can be made more effective.

At this time, after the pulp molding material PM is supplied to the frame 5 in which the lower mold 3 of the mold 2 is inserted, the lower mold 3 and the upper mold 4 are pressed while the upper surface thereof is pressed by the upper mold 4 having air permeability. Water vapor heated above the gelatinization temperature of the modified starch is supplied from the cavity 24 of the main body 18 for about one minute. Thereby, moisture and heat required for gelatinization are added to the pulp mold material PM, and the water vapor is added to the pulp mold material PM.
The modified starch is gelatinized by being evacuated upward around the entirety of the pulp, and the bonding force as a pulp molded article is imparted.

Further, as the heat molding apparatus, an apparatus having a structure as shown in FIG. 6 can be used. This heat molding apparatus uses hot air as a heating medium, and is a hot air heat molding apparatus that heats and molds a pulp mold material PM with hot air. The mold and compression device used in the hot air heating molding device 117 according to the second embodiment of the heat molding device are the same as the mold 2 and the compression device 10 of the first embodiment described above, Is omitted, and only the hot air heating molding device 117 will be described.

As shown in FIG. 6, the hot-air heating and molding apparatus 117 has a lower part formed by a main body 118 and an upper exhaust chamber 120 which is disposed continuously with the die housing chamber 119 vertically interposed therebetween. And a pressure regulating chamber 121 on the side thereof, and is held by a machine frame base 122. The mold accommodating chamber 119 can open and close the front wall portion, and the exhaust chamber 120 formed in a truncated pyramid shape can be jumped open with the rear end side of the mold accommodating chamber 119 as a fulcrum. Thereby, the attachment / detachment work of the mold 2 to / from the mold accommodating chamber 119 can be easily performed.

The mold accommodation chamber 119 and the pressure regulating chamber 121 are vertically divided by a mold support plate 123. The mold support plate 123 has a large number of air holes as a whole, for example.
The holes are drilled at a hole diameter of 6 mm and a pitch of 15 mm. The mold support plate 123 has a cavity 12 for inserting and holding the mold 2.
4 is installed in communication with the lower pressure regulating chamber 121.
The mold mounting surface portion 124a on the upper surface side of the cavity portion 124 includes:
An opening 125 into which the frame 5 of the mold 2 is inserted is formed. A toggle clamp 126 for fastening the frame 5 of the mold 2 at the flange 5b is attached to the surface surrounding the opening 125. In addition, the pressure regulating chamber 121
Is formed in the shape of an inverted truncated pyramid, and a water droplet prevention net 127 is stretched in the inside thereof.

The hot air heating and forming apparatus 1 thus configured
Each pipe is connected to a main body 118 of the pipe 17. An exhaust port 128 is provided on an upper surface portion 120 a of the exhaust chamber 120, and first and second air supply ports 129 and 130 with a valve and a drain port 13 with a valve are provided on a bottom surface 121 a of the pressure regulating chamber 121.
1 and are provided in parallel. The exhaust port 12 of the exhaust chamber 120
An exhaust pipe 132 is connected to 8. Further, a first pipe 133 for hot air supply is connected to a first valve air supply port 129 of the pressure regulating chamber 121, and a room temperature pressurized air air supply is connected to a second valve air supply port 130. Of the second pipe 134
Are connected. A drain pipe 135 for drainage is connected to the drain port 131 with a valve.

The exhaust pipe 132 is connected to a blower 136 for sucking air inside the main body 118 and discharging the air to the outside. The first pipe 133 is connected to a hot air blower 142 via a switching valve 137. Further, the second pipe 134 is connected to the compressor 141, and the drain pipe 135 is led to a drain.

As the pulp molding material PM which is heat-molded by the hot air heating molding device 117, a material having a higher moisture content than the pulp molding material PM which is molded by the steam heating molding device 17 using steam of the first embodiment is used. . That is, this pulp mold material PM has 30 to 8
Those having a water content of 0% by weight are used. The lower limit of 30% by weight is sufficient for the mixture of the paper pieces and the flocculent one with the hollow particles and the modified starch to be easily mixed and heated by the modified starch to gelatinize. Only the amount of water. In addition, the upper limit of 80% by weight
Is determined by the drying time and the releasability. Both the upper limit and the lower limit of the water content take into account the amount of water lost when heated by hot air.

Next, a process of heat-forming the above-described pulp molded article using the hot-air heating molding apparatus 117 configured as described above will be described. The moisture content of the pulp mold material PM used in this embodiment is 80% by weight based on the defibrated material.

First, the mold 2 taken out of the compression device 10
Is accommodated in the mold accommodating chamber 119 of the hot air heating and molding apparatus 117. In this accommodating operation, the front wall portion of the mold accommodating chamber 119 is opened, and the exhaust chamber 120 serving as the upper lid is jumped up and opened to expose the mold attaching surface 124a of the cavity portion 124 in the mold accommodating chamber 119. Then, the mold 2 is inserted into the opening 125, and the flange 5 b of the frame 5 is engaged and mounted on the mold mounting surface 124 a, and is tightened and fixed by the toggle clamp 126. After that, the front wall portion is closed and the exhaust chamber 120 is closed, so that the mold accommodating chamber 119 is sealed.

In this state, the first piping 13 of the pressure regulating chamber 121 is
While the switching valve 137 of No. 3 is opened, the drain 131 is closed, and the hot air blower 142 is driven to generate hot air.
With this, hot air set to a temperature of 100 ° C. to 110 ° C. when converted to heat at a pressure of approximately 1 atm to 1.5 atm flows from the first valved air supply port 129 through the first pipe 133. The air is sent to the pressure regulating chamber 121, and the pressure is equalized and supplied to the cavity 124 of the mold housing chamber 119. This hot air flows from the cavity 124 to the lower mold 3 and the ventilation holes 3 of the frame 5.
a and 5a, enters the mold 2, passes through the pulp mold material PM therein while heating and absorbing moisture,
The gas reaches the exhaust chamber 120 from the ventilation hole 4 a of the upper mold 4. The hot air containing the water vapor is exhausted from the exhaust port 128 of the upper surface 120a through the exhaust pipe 132 by being forcibly sucked by the exhaust fan 136.

As described above, the molded product of the pulp molding material PM supplied from the lower part of the mold 2 is heated, and the hot air that has passed through the molded product is discharged by the air blower 136 to about 0.5 atm. It is forcibly sucked and exhausted by negative pressure. The heating by the hot air and the forced exhaust are continued for a required time (several tens of seconds), the first supply port 129 with a valve is closed, the second supply port 130 with a valve is opened, and the compressor 141 is connected through the second pipe 134 to the compressor 141. Gas below the gelatinization temperature of the modified starch at a given pressure generated by
Dry normal temperature air of about atmospheric pressure is blown into the pressure regulating chamber 121, and this blowing is continued for several tens seconds.

After the completion of the blowing and forced evacuation, the mold 2 is taken out of the hot air heating molding apparatus 117, and the molded body of the pulp molding material PM is released. By heating the molded body of the pulp mold material PM in the mold 2 with hot air in this manner, the modified starch added as a binder is gelatinized, and the moisture of the gelatinized modified starch evaporates, thereby modifying the modified starch. Is sufficient to release the molded body from the mold 2. Thereby, the surface of the necessary portion is protected by the surface protection sheets 9a and 9b, and the pulp mold can be prevented from being broken or generating paper powder even when subjected to vibration or external force due to contact with the buffer. The molded body 1 can be manufactured.

When a thermoplastic plastic sheet is used as the surface protection sheets 9a and 9b, the plastic sheet set in the mold is softened and deformed by heating, and adheres to the surface of the mold. Even if the sheet is a plastic sheet, a surface protective layer conforming to the outer shape of the pulp molded article 1 can be formed. Further, in order to arrange the protective layer of the surface protective sheet along the uneven surface of the pulp molded article 1, a box made of three-dimensionally assembled paper or plastic can be used as a core material.

A second embodiment of the present invention shown in FIGS. 7 to 15 is a plastic sheet 4 as a surface protection member.
5 are provided with bulging portions 50a and 50b,
The pulp mold bodies 46a and 46b are integrally formed by filling the pulp mold material PM into the pulp mold material 50b, and the pulp mold bodies 43, 56, 60, and 61.

Of these, the pulp molded articles 43 and 56 shown in FIGS. 7 to 10 show an embodiment in which a support member is not attached to the back surface of the surface protection sheet. The pulp molded article 60 shown in FIGS. 11 to 13 is an example in which the same sheet as the surface protection sheet is adhered to the back surface of the surface protection sheet as a support member. Further, the pulp molded article 61 shown in FIGS.
Shows an example in which cardboard or other thick paper is adhered to the back surface of a surface protection sheet as a support member.

FIG. 7 shows a lower mold 44 constituting one of the molds according to the present embodiment, and a surface protection in which pulp mold bodies 46a and 46b are formed using the lower mold 44 and an upper mold (not shown). The plastic sheet 45 as a member is shown. The plastic sheet 45 has a sufficient number and number of ventilation holes 47 to allow the passage of water vapor or the like from the water vapor heating molding device 17 or the like during pulp molding.
Are drilled.

The ventilation holes 47 are formed, for example, by providing holes having a diameter of 6 mm at a pitch of 15 mm throughout the sheet, similarly to the ventilation holes provided in the surface protection sheets 9a and 9b, the mold and the like in the above-described embodiment. Is done. However, the diameter and pitch of the ventilation holes are not limited to this example. For example, while the hole diameter is reduced to 3 mm, the hole pitch is set to 8 mm, and the number of the holes is increased to increase the ventilation and communication. It is good also as a structure which secures aqueous. Furthermore,
It is not necessary to provide a ventilation hole as long as it is a material that allows sufficient passage of water vapor without providing a hole.

The plastic sheet 45 has a rectangular flat portion 45a and four side portions 45b continuous with the four corners of the flat portion 45a. The boundary between the flat portion 45a and each side portion 45b is Bending means such as perforations are provided so that each can be easily bent. Therefore, by bending the four side surfaces 45b at each perforation or the like, a bag body that opens upward with four surfaces surrounded by the side surface 45b with the flat surface 45a as the bottom surface is obtained.

The lower mold 44 is formed of a rectangular block having an appropriate thickness, and a cavity 48 is formed on the upper surface thereof. The cavity 48 of the lower mold 44
Has a shape corresponding to the plastic sheet 45 in plan view, and a core that can be fitted into the cavity 48 is provided in an upper mold (not shown). Further, pulp mold bodies 46a, 46
Forming holes 49a and 49b for forming b are provided. That is, two molding holes 49a are provided at positions of the cavity 48 corresponding to the flat portions 45a of the plastic sheet 45, and two molding holes 49b are provided at positions corresponding to the four side surfaces 45b. ing.
As shown in FIG. 8, a plurality of through holes 5 opening on the lower surface of the lower mold 44 are formed on the bottom surfaces of the molding holes 49a and 49b.
1 are provided.

The sheet pressing jig 52 as shown in FIG. 8A is used for forming the pulp mold bodies 46a and 46b using the lower mold 44 having such a configuration. The sheet pressing jig 52 has a plate-shaped jig main body having substantially the same shape as the planar shape of the cavity 48, and one surface of the jig main body has respective forming holes 49a, 4b.
Pressing protrusions 53a, 53 which are removably fitted to 9b.
3b is provided. The projecting portions 53a and 53b of the sheet pressing jig 52 form bulging portions 50a and 50b on the plastic sheet 45, and the bulging portions 50a and 50b are formed.
Mold material P in the recess set on the opposite side of
M is filled.

The molding operation of the pulp mold using the sheet pressing jig 52 is performed, for example, as follows. First, as shown in FIG. 8A, a plastic sheet 45 is fitted into a cavity 48 of the lower mold 44, a sheet pressing jig 52 is overlapped on this sheet, and molding holes 49a, 49b are formed via the plastic sheet 45. Pressing convex part 5
3a and 53b face each other. Then, by pressing the sheet pressing jig 52 and inserting the pressing protrusions 53a and 53b into the molding holes 49a and 49b, the bulging portions 50a and 50b are formed at predetermined positions of the plastic sheet 45, respectively.

In this case, a thermoplastic synthetic resin material is used as the plastic sheet 45, and when the sheet pressing jig 52 is inserted, the pressing convex portions 53 a and 53 b are heated to increase the temperature of the plastic sheet 45, so that the pressing convex portion is formed. The portions in contact with the portions 53a and 53b are made flexible to cause plastic deformation, and the bulging portions 50a and 50b can be formed easily and reliably.

Thereafter, as shown in FIG. 8B, the pulp molding material PM is filled into the recesses set inside the bulging portions 50a and 50b of the plastic sheet 45. Then, after the air-permeable upper mold is superimposed on the plastic sheet 45, the plastic sheet 45 filled with the pulp mold material PM is similar to the above-described embodiment.
Is set in a heat molding device such as the steam heat molding device 17. Thereafter, steam heated above the gelatinization temperature of the modified starch is supplied from below the mold for about one minute.

As a result, the steam flows around the entire pulp mold material PM, and the moisture and heat necessary for gelatinization are added to gelatinize the modified starch. The pulp mold bodies 46a and 46b
A certain degree of binding force is developed. At the same time,
By the gelatinization of the modified starch, the pulp mold material PM is adhered to the inner surface of the concave portion of the plastic sheet 45. As a result, as shown in FIGS. 8C and 9, a pulp molded product 43 having a plurality of pulp molded products 46 a and 46 b covered with a surface protection sheet on the other five surfaces except the back surface of the pulp molded product is obtained. It is formed. According to the pulp molded body 43, substantially the entire surface that may come into contact with the buffer object is covered with the plastic sheet 45, so that the pulp molded bodies 46 a and 46 b
This can reliably prevent destruction of the paper and peeling of the paper powder constituting the paper.

FIG. 10 shows a usage example of the pulp molded article 43 manufactured in this manner. 10A is a cross-sectional view of the pulp mold bodies 46a and 46b, and FIG. 10B is an electronic device (for example, a pulp mold body 43 or 56 mounted on a cardboard box 55 as an exterior body). A perspective view showing a state in which a buffered object 54 such as an audio speaker, a cassette tape recorder, etc.) is held, and FIG. C is a longitudinal sectional view at the center of FIG.

The corrugated cardboard box 55 includes four side plates 55a surrounding four sides of the buffered object 54, four upper plates 55b continuous above the respective side plates 55a, and a continuous lower plate below the respective side plates 55a. And four lower plates 55c. Then, of the four lower plates 55c, the lower plates 55c located on the sides facing each other are sequentially bent inward and overlapped to form a bottom portion, and the four upper plates 55c are formed.
The upper surface portion 55b is formed by sequentially bending the upper surface plates 55b located on the sides facing each other inward to overlap each other, thereby forming an upper surface portion.

On the bottom of the cardboard box 55, the flat portion 45a of the pulp mold 43 is
a is protruded upward, and each side plate 55a
Side portions 45b of the pulp molded body 43 are respectively arranged on the inner surface of the pulp molded body 43 with the pulp molded body 46b protruding inward. The buffer object 54 is inserted and held inside the pulp molded body 43, the buffer object 54 is supported by the pulp mold body 46a positioned below, and the pulp mold body 46b positioned laterally moves the buffered object 54b. Movement is regulated.

A pulp molded body 56 for the upper surface, which is separately manufactured, is disposed on the upper surface of the buffer object 54. The pulp molded body 56 is made up of a plastic sheet 56a having substantially the same size and structure as the plane portion 45a of the pulp molded body 43, and two pulp molded bodies 56b formed integrally with the plastic sheet 56a. The upward movement of the buffer object 54 is regulated by the pulp mold body 56b. still,
Flat portion 45a and side portion 45 of pulp molded article 43
As shown in FIG. 10C, the portion connecting to b may be bent at a right angle as shown by a solid line, or may be bent in an arc shape as shown by a two-dot chain line.

According to the pulp molded article 43,
Since the pulp mold bodies 46a and 46b can sufficiently exhibit the function as a cushioning material, and the surface protection member is formed of a plastic sheet 45 having a high flexibility, the pulp mold bodies 46a and 46b are used as cushioning materials.
The position of the buffer object 5 can be easily corrected.
4 can easily absorb changes in length and size.

As shown in FIGS. 11 to 13, a plastic sheet 57 as a support member is disposed on the back surface of the pulp molded article 43 and joined to the plastic sheet 45, and the whole pulp molding material PM is Pulp molds 58a,
The pulp molded body 60 having a structure obtained by molding the 58b can also be formed.

In this case, a mold and a sheet pressing jig for forming the pulp molded body 60 are the same as those shown in FIG.
8 and the plastic sheets 45 and 57 before and after wrapping the pulp mold material PM.
Of these, it is preferable to apply an adhesive such as a water-soluble adhesive to the joining surface of one sheet. By bonding the front and rear plastic sheets 45 and 57 with this adhesive, the integrity of the pulp molded article 60 can be further ensured. Note that, without applying the adhesive, the contact surfaces of the two sheets 45 and 5 were fused together.
7 may be joined.

The method of manufacturing the pulp molded article 60 is different from the method of manufacturing the pulp molded article 43 described above in that the pulp is formed in a concave portion set on the opposite side of the bulging portions 50a and 50b of the plastic sheet 45. Front plastic sheet 4 filled with mold material PM
5 is that the rear plastic sheet 57 is superimposed and adhered to the back surface of the sheet 5 so as to close the recess.

That is, as shown in FIG. 11A, the front plastic sheet 45 is attached to the lower mold 44 and a part thereof is bulged into the molding holes 49a and 49b.
The pulp mold material PM is filled in the recess set inside 50b. Thereafter, the rear plastic sheet 57 is overlapped so as to close the recess filled with the pulp mold material PM, and the contact surfaces of the two sheets 45 and 57 are joined together to be integrated. Subsequent steps are the same as in the case of FIG. 8C, and the bulging portion 5 is formed through the molding holes 49a and 49b.
11A, the pulp mold material P is removed from the lower mold 44 as shown in FIG. 11B.
A pulp molded article 60 having pulp molded articles 58a and 58b in which M is entirely covered with the surface protection sheet is obtained.

FIG. 13 shows an example of the use of the pulp molded article 60 thus manufactured. 13A is a cross-sectional view of the pulp mold bodies 58a and 58b, and FIG. 13B is a pulp mold body 43 mounted inside a corrugated cardboard box 55 as an exterior body. FIG. 6 is a cross-sectional view of a main part showing a state where the device is held. According to the pulp molded body 60, the entire surface of the pulp molded bodies 58a and 58b is
5, 5 and 57, it is possible to increase the holding force of the buffer object 54 and to more reliably prevent the pulp mold from being broken and the paper dust from being generated.

Further, as shown in FIGS. 14 and 15, a corrugated cardboard 62 as a plate-like member is arranged on the back surface of the pulp molded body 43 and joined to the plastic sheet 45.
The entire pulp molding material PM is converted into a plastic sheet 4
It is also possible to form a pulp molded body 61 having a structure in which the pulp molded bodies 63a and 63b are formed by being covered so as to be sandwiched between the pulp molded body 63 and the corrugated cardboard 62.

This embodiment differs from the embodiment shown in FIGS. 11 to 13 in that a cardboard 62 is used in place of the plastic sheet 57. As the plate-like member, cardboard, cardboard or other thick paper, plastic plate, wood or metal plate, or the like can be used as well as cardboard. Further, in this embodiment, the vent hole 64 is formed only in the portion where the pulp mold material PM is bonded, instead of providing the vent hole in the entire cardboard 62. This configuration can also be applied to the plastic sheet 45. Other configurations and manufacturing methods are the same as in the above-described embodiment.

FIG. 15 shows an example of the use of the pulp molded article 61 thus manufactured. 15A is a cross-sectional view of the pulp mold bodies 63a and 63b, and FIG. 15B is a pulp mold body 61 as a box.
FIG. 9C is a perspective view showing a pulp molded body 65 serving as a lid and a pulp molded body 61, 65 mounted inside a cardboard box 55 serving as an exterior body. It is principal part sectional drawing which shows the holding | maintenance state.

As shown in FIG. 15B, the pulp molded body 61 formed as described above is
The side part 61b is bent at a right angle to 1a to assemble it into a box. The buffered object 54 is fitted into this casing, and the buffered object 54 is supported from below by a pulp mold 63a provided on the flat portion 61a of the pulp molded body 61, and is attached to each side surface 61b surrounding the four sides. By supporting the buffered object 54 from the side with the provided pulp molded body 63b, the buffered object 54 is securely held by the pulp molded body 61 as a cushioning material. The vertical movement is regulated by the pulp molded body 65 mounted so as to close the upper opening side.

The pulp molded article 65 has the same configuration as the pulp molded article 61, and includes a plastic sheet 45 as a surface protection member and a cardboard 62 as a support member, and is provided between these. A pulp mold body 65a filled with a pulp mold material is formed.

According to the pulp molded articles 61 and 65 having such a configuration, the pulp molded articles 63a and 63
Since the entire surfaces of 3b and 65a are covered with the plastic sheet 45 and the cardboard 62 without leakage, it is possible to more reliably prevent breakage of the pulp mold and generation of paper dust. In addition, since the rigidity of the cardboard 62 is relatively high, as shown in FIG. 15B, the whole is assembled into a box, and the buffer object 54 is fitted and held therein as shown in FIG. The buffer 54 is securely held by the tall box to prevent its movement, and the buffer 54 is used as a cushioning material.
Can always be held at a predetermined position in a predetermined state.

When the plastic sheet 45 is relatively difficult to adhere to the pulp molding material PM,
An adhesive may be applied to the surface of the plastic sheet 45 or the cardboard 62 on the pulp mold material PM side in advance. As a result, apart from the adhesive force of the modified starch of the pulp mold material PM, the adhesive force of the adhesive is further added, and a pulp molded article in which the bonding strength of the pulp molded article is enhanced is obtained.

The pulp molded article according to the present invention can of course be used as a cushioning material for protecting only a necessary part by mounting it on a part of an object to be buffered. In this case, after the pulp molded article is attached to a required portion of the buffered object, an appropriate position of the plastic sheet 45 is fixed to the buffered object with an adhesive tape or the like, so that the pulp molded article is moved to a predetermined position of the buffered object. It can be prevented from moving out of position.

Next, a third embodiment of the present invention will be described with reference to FIGS. In this embodiment, a pulp mold body 71a, 71b is formed by sticking a surface protection piece only to the tip of the pulp mold body,
1 shows a pulp molded article 70 that protects only a portion that comes into contact with an object to be buffered. In this embodiment, a mold 72 having a configuration as shown in FIG. 16 is used.

This mold 72 is made of a pulp mold 71
a and 71b, and a mold body 7
3 includes a mold outer frame 74 covering the other five surfaces except for the upper surface of the mold 3, and a mold upper lid 75 covering the upper surface of the mold body 73. The mold body 73 is formed of a rectangular block, and the mold body 73 is provided with molding holes 76a, 76b for molding the pulp mold bodies 71a, 71b so as to penetrate between the upper and lower surfaces. . One molding hole 76a of the mold body 73 is a hole that opens linearly from the upper surface to the lower surface, and the other molding hole 76b is a hole in which a step is set in the middle. I have. Therefore, one pulp molded body 71a is formed as a prismatic convex, and the other pulp molded body 71b is formed as a prismatic convex having a step in the middle.

The mold outer frame 74 has the mold body 7 on its upper surface.
3 is a box-shaped box body having a concave portion 77 into which is inserted and fitted, and all the bottom and side surfaces thereof have vent holes 7 sufficient to allow water vapor to pass therethrough during pulp molding.
8 are drilled. The mold upper lid 75 is made of a plate that can cover the entire upper surface of the mold outer frame 74,
As in the case of the mold outer frame 74, a large number of ventilation holes 79 sufficient to allow water vapor to pass during pulp molding are formed on the entire surface.

In the molding holes 76a, 76b of the mold body 73 of the mold 72 having such a configuration, surface protection pieces 80, 81 showing another embodiment of the surface protection member are set.
The surface protection pieces 80 and 81 are made of a pulp mold body 71.
It has a shape corresponding to the distal end shape of a, 71b, and is attached to the distal end portion of the molding holes 76a, 76b. One surface protection piece 80 has a shape in which a rectangular rectangular sheet is bent at a plurality of locations in the longitudinal direction, and is attached to the tip end surface of the molded body. Further, the other surface protection piece 81 is formed of a rectangular housing having an opening on one surface, and is mounted so as to cover the tip of the molded body of the pulp molding material PM.
These surface protection pieces 80 and 81 also have a large number of ventilation holes 80.
a and 81a are provided respectively.

The mold 72 having such a configuration is used, for example, in the following manner, whereby the pulp mold 71 with the surface protection pieces 80, 81 adhered to the tips.
The pulp molded article 70 having the components a and 71b is manufactured. In the case of the mold 72 shown in FIG. 16, first, the mold body 73 is fitted into the concave portion 77 of the mold frame 74, and the surface protection pieces 80, 81 are inserted into the molding holes 76a, 76b, respectively. Then, it is laid so as to be in contact with the inner surface of the mold frame 74. In the case of the lower mold 44 shown in FIG.
The surface protection pieces 80 and 81 are inserted into 9a and 49b, respectively, and are laid so as to be in contact with the bottom surfaces thereof.

Next, as shown in FIG.
The pulp molding material PM is filled in 9a, 49b or 76a, 76b, a plastic sheet 57 or a corrugated cardboard 62 is overlaid thereon, and a mold lid 75 is placed thereon, thereby pressing the pulp molding material PM. Subsequent steps are the same as those in the above-described embodiment. The steam is supplied to the steam heating molding device 17 or the like, and the pulp mold material PM is molded and fixed by heating while giving appropriate humidity.

As a result, as shown in FIG. 17B, a pulp molded body 70 in which the back surfaces of the pulp molded bodies 71a and 71b are adhered to the plastic sheet 57 is obtained.
Also, as shown in FIG.
A pulp molded article 70 having the back surface 1b adhered to the cardboard 62 is obtained. These pulp molded articles 7
Since the surface protection pieces 80 and 81 are respectively adhered to the leading end of the zero, the destruction of the pulp mold bodies 71a and 71b and the separation of the paper powder constituting the pulp mold bodies 71a and 71b can be reliably prevented.

The surface protection piece is not integrally formed with the pulp molding material PM as described above, but is formed as shown in FIG.
As shown in (1), after the pulp mold body is formed, the surface protection pieces 82 and 83 may be adhered to the front end surface or the front end portion thereof using a fixing means such as an adhesive. The one surface protection piece 82 can protect only the tip end surface of the pulp mold body 71a, and is formed by bending a strip-shaped sheet member into a crank shape. The other surface protection piece 83 is a pulp mold body 71b.
A predetermined range of the front end of the sheet member can be protected, and is formed so as to form a housing by bending four sides of a sheet member provided in advance to a predetermined width.

FIG. 20 shows a usage example of the pulp molded article 70 thus manufactured. 20, FIG. 20A is a cross-sectional view of the pulp mold bodies 71a and 71b, and FIG. 20B is a view showing a box body as one buffer formed by combining two pulp mold bodies 70. . Each pulp molded product 70 is composed of three side plates 84a surrounding three sides and a bottom plate 84b surrounding these bottom portions, and one box body is formed by overlapping one side portion opening to each other. It is configured.

In the embodiment of the mold 72 shown in FIG.
Vent holes 78 and 7 are formed in the entire mold outer frame 74 and the mold lid 75.
9 has been described, but the forming holes 76a, 7
6b, the ventilation holes 78, 79 may be provided only around the molding holes 76a, 76b. In addition, the shape of the surface protection piece that is adhered and fixed to the tips of the pulp mold bodies 71a and 71b is not limited to that of the present embodiment. For example, a housing that can cover the entire molded body It may be something like

As described above, the present invention is not limited to the above-described embodiment. In the above-described embodiment, an example in which the pulp molded article is applied to a cushioning material accommodated in an outer casing such as a cardboard box is described. Although described, it goes without saying that, for example, the pulp molded article itself can be used as a packaging container. Thus, the present invention can be variously modified without departing from the spirit thereof.

[0101]

As described above, according to the present invention,
Since the surface protection member is adhered to part or all of the surface of the pulp mold material, the surface of the portion of the pulp mold body that comes into contact with the buffer can be reliably protected. Therefore, even when an external force such as vibration or impact due to contact with a buffered object such as a television or an audio device is input, the buffered object can be reliably protected, and the pulp mold body may be broken by the external force. Provided is a pulp molded article capable of preventing paper powder from peeling off from the surface thereof, and a method of manufacturing a pulp molded article capable of easily and efficiently producing the pulp molded article. Can be.

Although the pulp molding material has a specific gravity about 5 times that of styrene foam, a pulp molding body is provided only on a required portion of the surface protection member, and the pulp molding body is arranged only on a portion that comes into contact with the buffer. By suppressing the increase in the weight of the entire pulp molded article, it is lightweight as a whole, and when used as a cushioning material, it is less likely to appear as an increase in the packing weight of the material to be buffered, and the transportation weight is reduced. The effect is obtained that reduction can be achieved or increase in weight can be minimized.

[Brief description of the drawings]

FIG. 1 is a perspective view showing a first embodiment of a pulp molded article molded using a pulp mold material according to the present invention.

FIG. 2 is a sectional view showing a first embodiment of the pulp molded article shown in FIG. 1 and a mold for molding the molded article.

FIG. 3 is an exploded perspective view of the first embodiment of the mold shown in FIG. 2;

FIG. 4 is a perspective view showing a first embodiment of a compression device according to the present invention for compressing a pulp mold material filled in a mold shown in FIG. 3;

FIG. 5 is a system diagram showing a configuration of a first embodiment of a heat forming apparatus according to the present invention for supplying steam to the mold shown in FIG. 2;

FIG. 6 is a system diagram showing the configuration of a second embodiment of the heat forming apparatus according to the present invention.

FIG. 7 is a perspective view showing a second embodiment of the mold according to the present invention.

8 shows the use state of the mold shown in FIG. 7, wherein FIG. A shows a state before the surface protecting member is pushed into the mold by the pressing plate, and FIG. FIG. C is an explanatory view showing a state in which the pulp mold is taken out from the mold, and FIG.

FIG. 9 is a perspective view showing a second embodiment of the pulp molded article of the present invention formed using the mold shown in FIG. 7;

10A and 10B illustrate a use state of the pulp molded article shown in FIG. 9; FIG. 10A is a cross-sectional view of the pulp molded article; FIG. FIG. C is a longitudinal sectional view of FIG.

11A and 11B illustrate a method of manufacturing a pulp molded article according to a third embodiment of the present invention. FIG. 11A shows a state where a pulp mold material is filled in a concave portion of a surface protection member, and FIG. It is explanatory drawing which shows the state which takes out a pulp molded body from each.

FIG. 12 shows a third example of the pulp molded article of the present invention formed by using the mold and the surface protection member shown in FIG.
It is an exploded perspective view showing an example.

13A and 13B are diagrams illustrating a use state of the pulp molded article illustrated in FIG. 10, wherein FIG. A is a cross-sectional view of the pulp mold body, and FIG. is there.

14 shows a state in which a pulp molded body is molded using cardboard instead of the plastic sheet as the surface protection member shown in FIG. 11, and FIG. And FIG. B is an explanatory view showing a state in which the pulp molded article is taken out from the mold.

15A and 15B illustrate a use state of the pulp molded body shown in FIG. 14, wherein FIG. 15A is a cross-sectional view of the pulp molded body, and FIG. 15B is a perspective view illustrating an assembled state of the pulp molded body. FIG. C is a longitudinal sectional view of a state in which the buffer object is held by the cushioning material assembled according to FIG.

FIG. 16 is an exploded perspective view showing a third embodiment of the mold according to the present invention.

FIGS. 17A and 17B illustrate a method of manufacturing a pulp molded article according to a fourth embodiment of the present invention. FIG. 17A shows a state in which a pulp mold material is filled in a concave portion of a surface protection member, and FIG. It is explanatory drawing which shows the state which takes out a pulp molded body from each.

FIG. 18 is a perspective view showing a pulp molded product formed by using the mold shown in FIG.

FIG. 19 is a perspective view showing a state where a surface protection piece is adhered to a molded product of a pulp molded product molded by using the mold shown in FIG. 17;

20 shows a use state of the pulp molded article shown in FIG. 18, wherein FIG. 20A is a sectional view of the pulp molded article, and FIG. 20B is a perspective view for explaining an assembled state of the pulp molded article. .

[Explanation of symbols]

1, 43, 56, 60, 61, 65, 70 Pulp molded article, 2, 72 Mold (mold), 9a, 9
b Surface protection sheet (surface protection member), 10 compression device, 16, 58a, 58b, 63a, 63b, 71
a, 71b pulp mold body, 17 steam heating molding device (heating molding device), 44 lower mold, 45, 57
Plastic sheet (surface protection member), 52 sheet pressing jig, 54 buffer object, 62 cardboard (plate-like member), 80, 81 surface protection piece (surface protection member),
117 Hot air heating molding device (heating molding device), PM
Pulp mold material

Claims (10)

[Claims] 1. A pulp molding material containing pulp as a main raw material and containing a starch-based binder and heat-expandable hollow particles, by adding moisture and heating the pulp-molded material to a predetermined temperature or higher to gelatinize the starch-based binder and to produce the pulp. And a heat-expandable hollow particle, thereby forming a pulp mold body, and a surface protection member is adhered to a part or the entire surface of the pulp mold body. 2. The pulp molded article according to claim 1, wherein the surface protection member is formed of a paper or a plastic sheet having air and water permeability through which water vapor can pass between the front and back surfaces. A pulp molded article characterized by covering and protecting the surface. 3. The pulp molded article according to claim 1, wherein the surface protection member is formed of a paper or plastic sheet having air and water permeability through which water vapor can pass between the front and back surfaces, and a base member. A pulp molded article, wherein the surface protection sheet covers and protects the surface of the pulp molded article, and the base member fixes and supports the back surface of the pulp molded article. 4. The pulp molded article according to claim 1, wherein the pulp is made of a mixture of a paper piece obtained by cutting waste paper into several mm or less and a cotton-like defibrated material obtained by further pulverizing the paper piece. Characteristic pulp molded product. 5. The pulp molded article according to claim 1, wherein the starch-based binder is an acetylated modified starch or an esterified modified starch in which a part of hydroxyl groups in the starch molecule is modified. Pulp moldings to be made. 6. The pulp molded article according to claim 1, wherein the heat-expandable hollow particles are such that a polymer of an outer shell covers hydrocarbons of an inner shell, and the polymer of the outer shell is softened by heating, and the inner polymer is heated. A pulp molded article, wherein the shell hydrocarbon is particles that expand by gasification. 7. The pulp molded article according to claim 1, wherein the pulp molded article is disposed at a plurality of locations on the surface protection member so as to contact a plurality of locations on the buffered article. A pulp molded article characterized by being used as a cushioning material by being supported by individual pulp molded articles. 8. A mold is filled with a pulp mold material containing pulp as a main raw material and containing a starch binder and thermally expandable hollow particles, and water for gelatinizing the starch binder is added to the pulp mold material. After the addition, the starch-based binder is gelatinized by heating to a temperature equal to or higher than the gelatinization of the starch-based binder, and the pulp and the thermally expandable hollow particles are combined to form a pulp mold body. A method for producing a pulp molded article, characterized in that a surface protection member is adhered to a part or the whole of the surface of the molded article. 9. The method for producing a pulp molded article according to claim 8, wherein the supply of water to the pulp mold material and the heating are performed by steam heated to a temperature at which the starch-based binder gelatinizes. A method for producing a pulp molded article, characterized by comprising: 10. The method for producing a pulp molded article according to claim 8, wherein the pulp molding material is heated by hot air heated to a temperature at which the starch-based binder gelatinizes. A method for producing a molded article.