JPH05209083A - Production of reclaimed cushioning body - Google Patents

Abstract

PURPOSE:To provide a method for producing a reclaimed cushioning body of practical use readily in a short time from a waste cushioning material comprising a thermosetting resin or a synthetic polyolefinic resin having a relatively poor adhesive force or from a waste unfoamed material such as rubber chips. CONSTITUTION:A cushioning material 10 comprising a synthetic resin foam or its mixture with a different material such as rubber is crushed into small pieces of about 2-30mm in size. The crushed pieces are mixed with small pieces 11 of polystyrene foam, and the mixture is densely enclosed in a hermetically sealed container 12. The container 12 is then filled with a combustible gas 20, and the gas 20 is explosively burned to join the pieces of the cushioning material by bonding, thus giving the objective cushioning body.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing a regenerated buffer from waste of a synthetic resin buffer.

[0002]

2. Description of the Related Art Since synthetic resin foams such as polyurethane foams and polyethylene foams are lightweight and have excellent heat insulating properties and shock absorbing properties, they are widely used as cushioning materials, packaging materials, heat insulating materials, heat insulating materials, etc. There is.

However, in recent years, due to the large amount of foam used, the amount of foam discharged as a waste also becomes enormous, and its treatment has become a problem. In particular, recently, the global environment has become a major social issue, and the reduction of waste and the effective use of resources have been called for, and the recycling of foam has been required.

The following methods have been proposed for treating foam waste. One of them is to pulverize soft polyurethane foam etc. as waste into small pieces, mix the foam strips with an adhesive and heat the mixture under pressure to bond the foam strips and regenerate them. It is a method of manufacturing a buffer. The other method is a method in which a thermoplastic resin foam as waste is finely crushed and the foam pieces are pressed against a heater heated to a temperature below the ignition point of the foam to perform a melting treatment. (Described in JP-A-62-205138)

However, in the former method using an adhesive, when a regenerated buffer is produced from a thermoplastic resin foam, particularly a polyolefin foam waste such as polyethylene foam or polypropylene foam,
Since these foams are poor in adhesiveness, the regenerated buffer obtained is easy to separate into the original foam pieces, and there is a problem that it is difficult to obtain a practical regenerated buffer.

Further, in the latter method, since the foam strip must be pressed against the heater to melt it, the pores of the foam strip are easily crushed and a uniform regenerating buffer cannot be obtained. There is a problem that the processing such as the melting takes time. Further, the foam strip must be pushed out of the melting furnace while being pressed against the heater, which causes a problem that the device becomes complicated.

The inventors of the present invention previously stored the thermoplastic resin foam strips in a container tightly, filled the container with a combustible gas, and explosively burned the thermoplastic resin foam strips. Provided is a method for producing a regenerated foam by fusing the surfaces together to form a single foam. (Japanese Patent Application No. 3-29584)

According to this method, a practical recycled foam can be easily obtained from the waste of the thermoplastic resin foam.

However, in this method, when the thermoplastic resin foam is the above-mentioned polyolefin-based foam, the adhesive strength between the strips is poor, and the shape of the regenerated foam obtained may be lost. was there. In addition, it cannot be applied to non-foamed materials such as rubber chips and resins other than thermoplastic resins.

[0010]

SUMMARY OF THE INVENTION The present invention has been proposed in order to solve the above problems,
It is possible to easily and practically obtain a reclaimed buffer body having practicality from a thermosetting resin buffer body, a polyolefin-based synthetic resin buffer body having relatively poor adhesive strength, or a non-foamed waste such as a rubber chip. An object of the present invention is to provide a method of manufacturing a regenerative buffer that can be used.

[0011]

That is, the present invention is
The synthetic resin foam or the synthetic resin foam and a cushioning material made of a different material such as rubber are crushed into strips having a size of about 2 to 30 mm, and the strips and the polystyrene foam strips are mixed, and The mixture is tightly housed in a closed container, then the closed container is filled with a combustible gas, the combustible gas is explosively burned, and the buffer material strips are integrally joined to obtain a buffer body. The present invention relates to a method for manufacturing a regeneration buffer body.

[0012]

The mixture of the cushion material strip and the polystyrene foam strip contained in the container is expanded by the explosive combustion heat of the flammable gas filled in the container, and the thermoplastic resin foam in the polystyrene foam and the buffer material is foamed. Even if the olefin resin, urethane, rubber, etc. that the body surface melts and is difficult to adhere,
Adjacent strips are joined and integrated to form one regeneration buffer. At that time, if the mixture is densely housed in a container in a compressed state, adjacent strips are pressed against each other by the restoring force and are welded to each other, so that the welding is sure and strong. Moreover, since the bonding force is larger in welding than in bonding, there is no fear that the shape of the obtained cushioning body will collapse. In addition, the explosive combustion of flammable gas occurs instantly, and the generated pressure is evenly applied to the strip inside the container.Therefore, the time required to manufacture the regenerative buffer is extremely short, and the pores of the regenerative buffer are obtained. Is also uniform.

[0013]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below with reference to the accompanying drawings. FIG. 1 is a cross-sectional view of an airtight container at the time of accommodating a mixture of strips in an embodiment of the method for producing a regeneration buffer of the present invention, FIG. 2 is a perspective view showing an example of an airtight container used in the method of the present invention, and FIG. FIG. 4 is a perspective view showing an example of a net cage, FIG. 4 is a cross-sectional view showing another example of the manufacturing method of the present invention, FIG. 5 is a cross-sectional view showing a pressed state, FIG. It is a perspective view which shows the time of taking out a buffer.

First, the cushioning material made of plastic and / or rubber is pulverized in advance by a crusher to obtain a cushioning material strip 10. In this embodiment, polyethylene foam waste is used as the cushioning material.

As the cushioning material used in the present invention, in addition to polyethylene, thermoplastic resin foams such as polypropylene, polyvinyl chloride and polystyrene, thermosetting resin foams such as polyurethane, butyl rubber, SBR and NBR.
One kind or a mixture of two or more kinds of rubber materials such as is used.

The size of the buffer material strip 10 is about 2 to 30.
mm is preferred. If the size of the strip is smaller than 2 mm, the strip may be melted and lost due to explosive combustion. On the other hand, if it is larger than 30 mm, not only the gap between the strips becomes large and the adhesion becomes incomplete, but also the amount of polystyrene foam for adhering the strips increases and the cost may increase. The size of the strips 10 does not have to be uniform, but rather the strips are preferably formed in a non-uniform manner so that they can be densely housed in a container.

Polystyrene foam strips 11 are mixed and dispersed in this buffer strip 10 to obtain a strip mixture. This polystyrene foam strip 11 is used as a binder to enter between the buffer strip 10 and join the cushion strips 10 together, and polystyrene foam waste is used. The polystyrene foam strip 11 is previously crushed by a crusher similarly to the buffer strip 10, and the size thereof is slightly smaller than the size of the buffer strip 10, preferably 2 to 5 mm. In this example, the cushion strip 10 and the polystyrene foam strip 11
And the mixing ratio is 7: 3 (volume ratio). It should be noted that the mixing amount of the polystyrene foam strip 11 is appropriately set depending on the type and amount of the cushioning strip to be welded, and when the cushioning strip is a thermosetting resin or a rubber chip, the amount is increased to practical use. It is preferable to impart a specific adhesive force. At that time, the polystyrene foam strips 11 can be effectively attached to the cushioning strips 10 by generating static electricity in the cushioning strips 10.

1.5 to 1.8 cubic meters of the resulting mixture are converted into internal dimensions of 1005 × 2005 × 50 as shown in FIG.
A thickness of 5 mm with an internal volume of about 1.0 cubic meter 2
It is housed and sealed in a 0 mm iron plate hermetic container 12.

An example of the closed container 12 is shown in FIG. The closed container 12 has strength enough to endure explosive combustion of flammable gas and high tightness for effective filling of flammable gas. The closed container 12 has a lid 13 formed on one side so that it can be opened and closed, and one end thereof is connected to a suction pipe 14 and a gas filling pipe 15 connected to a vacuum pump (not shown) and a power source (not shown). A spark plug 16 and a pressure gauge (not shown) are provided. The spark plug 16 used is for an automobile.

The mixture of strips is packed in advance in a net cage 17 as shown in FIG. 3, and the net cage 17 is housed in the closed container 12. An upper portion of the net cage 17 is a lid 18 that can be opened and closed. Also,
The mesh of the mesh basket 17 is formed in a size such that the mixture of fine particles does not pop out. This makes it easier to store the mixture of debris in the closed container 12 and prevents the regeneration buffer from sticking to the wall surface of the closed container 12 during explosive combustion.

Next, the vacuum pump is actuated to suck out the air in the closed container 12 through the suction pipe 14, and when the internal pressure reaches 20 mmHg, the operation of the vacuum pump is stopped and the suction pipe 14 is provided. Close the valve (not shown) provided. The reason for sucking the air in the airtight container 12 to the outside is that if a large amount of air is present in the airtight container 12, not only is it difficult to fill the flammable gas described below, but the explosive combustion power of the flammable gas is This is because it will decrease.

Then, the volume ratio of hydrogen to oxygen is 2:
The flammable gas 20 mixed with 1.1 is filled into the closed container 12 through the gas filling pipe 15 at a rate of 0.5 cubic meters / minute. The pressure in the closed container 12 is 760 mm
At the time of reaching Hg, the valve (not shown) of the gas filling pipe 15 is closed. Filling time for flammable gas is about 2
It was a minute. The flammable gas is pressurized (for example, at a pressure of 2.5 to 3 kg / cm ² ) to be filled in the closed container 12, so that energy at the time of explosive combustion can be increased and welding can be performed more efficiently. it can.

As the combustible gas 20 in the method of the present invention, a mixture of various oxidants and oxidants is used. Hydrogen is most suitable as the oxidizable agent, but methane, ethane, propane, ethylene, propylene, acetylene and the like can also be used. On the other hand, oxygen is most suitable as the oxidant, but air, ozone, etc. can also be used. The optimum mixing ratio of the oxidizer and the oxidizer varies depending on the kind of the oxidizer and the oxidizer or the material of the synthetic resin foam used, but for example, hydrogen and oxygen are 2: 1 in volume ratio, Alternatively, the volume ratio of acetylene and oxygen is 2: 5. The explosive combustion of the combustible gas is performed by igniting the combustible gas 20 by the ignition plug 16 in the closed container.

The valve of the gas filling pipe 15 is left for 1 minute with the valve closed so that the combustible gas is evenly distributed in the closed container 12 and between the buffer material strips 10.
After that, the ignition plug 16 is ignited, and the combustible gas in the closed container 12 is exploded and burned. Immediately after that, the pressure in the closed container is adjusted to 760 by using the gas filling pipe 15.
Carbon dioxide is introduced into the closed container 12 until it returns to mmHg. This is because the explosive combustion of the combustible gas 20 is ended in an instant, and the entire strip mixture is prevented from being melted.

The pressure in the closed container, which has been reduced by the explosive combustion of the combustible gas, is set to the atmospheric pressure of 760 mmH.
The reason for returning to g is to make it easier to open the lid 13 of the closed container when the regeneration buffer is subsequently taken out.

1 was introduced by introducing carbon dioxide into the closed container 12.
After a lapse of minutes, the lid 13 of the closed container 12 is opened to open the net cage 17
Take out and then 500 × 100 from the mesh basket 17
One regeneration buffer consisting of a 0 × 2000 mm rectangular parallelepiped was taken out. The obtained regenerated buffer is a uniform one in which the polystyrene foam strips mixed and dispersed are melted and the adjacent strips of cushioning material are bonded together and firmly integrated, and the pores are hardly collapsed. there were.

4 to 7 show another embodiment of the present invention. First, as shown in FIG. 4, 1.47 cubic meters of the strip mixture used in the previous example is accommodated in an iron net cage 41 having an internal dimension of 1000 × 2000 × 700 mm and an internal volume of 1.4 cubic meters. did. The same reference numerals as those in FIG. 1 denote the same members in the drawings. The amount of the mixture of the strips was determined such that the strips were not excessively dense in the closed container and the contact area with the flammable gas described later was sufficient. In addition, the net cage 41
Has an opening at the top and a part of the side surface that can be opened and closed by a lid 48, and the mesh has a size such that the buffer material mixture contained therein does not pop out.

Then, the mesh basket 41 was housed in a closed container 42. The closed container 42 is made of an iron plate having a thickness of 70 mm, has an inner size of 1050 × 2050 × 780 mm, and can be opened / closed by a lid 43. In the figure, reference numeral 44 is a suction pipe whose one end is connected to a vacuum pump (not shown), 45 is a gas filling pipe, and 49
Is a spark plug connected to a power source (not shown).

A press plate 46 connected to an external hydraulic cylinder 47 is provided on the top of the closed container 42.
2 and the inside of the net cage 41 so as to be vertically movable.
A silicon mold release agent is applied to the lower surface of the press plate 46, and the hermetically sealed container 42 is used until the explosive combustion of combustible gas described later.
It is arranged at the top. The press plate 46 has a size of 980 ×
It is 1980 x 20 mm.

Then, by operating the vacuum pump, the air in the closed container 42 is sucked out through the suction pipe 44, and when the internal pressure reaches 20 mmHg, the operation of the vacuum pump is stopped and the suction pipe 44 is provided on the way. Close the valve (not shown) provided.

Then, the combustible gas 20 used in the previous embodiment, in which the volume ratio of hydrogen and oxygen was adjusted to 2: 1.1.
Is filled into the closed container 42 through the gas filling pipe 45 at a rate of 0.5 cubic meters / minute. Closed container 42
When the internal pressure reaches 760 mmHg, the valve (not shown) of the gas filling pipe 45 is closed. The filling time of the flammable gas was about 2 minutes.

The valve of the gas filling pipe 45 is left closed for 1 minute so that the combustible gas is evenly distributed in the closed container 42 and between the buffer material strips 10. After that, the ignition plug 49 is ignited, and the flammable gas in the closed container 42 is exploded and burned.

Immediately after the explosive combustion of the combustible gas, as shown in FIG. 5, the hydraulic cylinder 47 is operated to lower the press plate 46, and the buffer body is pressed to a height of 40 mm. The time required for pressing was about 20 seconds.

After the mixture of the strips is pressed by the press plate 46 for 3 minutes and 30 seconds, the pressure in the closed container is increased through the gas filling pipe 45 while maintaining the pressed state. Carbon dioxide is introduced into the closed container 42 until the pressure returns to 760 mmHg, and the hydraulic cylinder 47 is operated as shown in FIG.
6 is returned to the upper part of the closed container 42 to release the press.

As shown in FIG. 7, the lid 43 of the closed container 42 was opened to take out the net-like basket 41, and the lid 48 was opened to take out one regeneration buffer 50. The obtained buffer 50
Is a rectangular parallelepiped measuring 1000 × 2000 × 400 mm, and the adjacent cushioning material strips are joined together by the mixed polystyrene foam strips and are firmly integrated by pressing, and the pores are almost collapsed. It was not uniform.

[0036]

As shown and described above, according to the manufacturing method of the regenerating buffer of the present invention, the plastic and the
Or by dispersing polystyrene foam strips in rubber shock-absorbing strips, tightly storing both strips in a closed container, and filling the closed container with a flammable gas to explode and burn, Since the polystyrene foam strips are melted and the cushioning strips are welded together, it is practical even for non-foams such as rubber chips or wastes of polyolefin-based synthetic resin with relatively poor adhesion. The regeneration buffer can be easily obtained in a short time, and has great advantages in terms of reduction of industrial waste and effective use of resources.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a closed container at the time of accommodating a strip mixture in an embodiment of a method for manufacturing a regeneration buffer of the present invention.

FIG. 2 is a perspective view showing an example of a closed container used in the manufacturing method of the present invention.

FIG. 3 is a perspective view showing an example of a net cage.

FIG. 4 is a sectional view showing another example of the manufacturing method of the present invention.

FIG. 5 is a cross-sectional view showing a pressed state.

FIG. 6 is a cross-sectional view showing when the press is released.

FIG. 7 is a perspective view showing the time when the reproduction buffer is taken out.

[Explanation of reference numerals] 10 cushioning material strips 11 polystyrene foam strips 12 closed container 17 reticulated basket 20 flammable gas

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁵ Identification code Internal reference number FI technical display B29K 105: 26

Claims (2)

[Claims] 1. A synthetic resin foam or a synthetic resin foam and a cushioning material made of a different material such as rubber are crushed into strips having a size of about 2 to 30 mm, and the strips and the polystyrene foam strips are separated. With mixing, the mixture is tightly housed in a closed container, then filled with a flammable gas in the closed container,
A method for producing a regenerative buffer body, comprising the step of explosively burning the combustible gas to join the buffer material strips together to obtain a buffer body. 2. The method for producing a regenerated buffer body according to claim 1, wherein after the explosive combustion of the combustible gas, the buffer material strip in the closed container is pressed.