JPH1058476A - Method for producing continuous molded body of air-permeable and water-permeable foamed resin - Google Patents

Abstract

(57) [Summary] The conventional technology is a so-called batch processing method.
The molding process was performed for each predetermined amount, and was not performed continuously. Alternatively, in the case of foaming by heating in the continuous moving process, since the method for simultaneously forming the voids for ensuring the air permeability, the operating conditions are complicated at present, and there are many variations in molded products. Was done. A plurality of foams made of a thermoplastic resin are continuously supplied into a continuous partitioned mold having a conveying means, and a partial surface of each of the supplied foams is sequentially fused to each other. By doing so, a continuous body having a large number of communicating voids is formed. The foam to be supplied into the compartment mold is
A foam that is appropriately foamed is used, but it may be further foamed in a compartment mold after the supply.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a foamed resin molded article having air permeability and water permeability, and more particularly, to a method for producing a continuous air-permeable and water-permeable foamed resin molded article formed as a continuous body having a large number of interconnected voids. About.

[0002]

[Prior art]

(A) Conventionally, examples of a foamed resin molded article having air permeability and water permeability (or water permeability) and a method for producing the same are described in JP-A-55-88949, “Foamed resin model for mold”,
-93339 "Drainage material for culvert", JP-A-4-15302
6 "Vented and water-permeable foamed resin molded article and method for producing the same".

The technology disclosed by these applications is summarized as follows. A large number of granular foams obtained by heating and foaming a synthetic resin are adhered and accumulated by an adhesive or fused and accumulated by a heating means to form a molded body. Was to do.

(B) Further, as an example of a foamed resin continuous molded article having air permeability and water permeability and a method for producing the same, JP-B-53-21898, “Method for producing open-cell foam” and JP-B-58-58370, Manufacturing method of open cell "
60499 "Method for producing open-cell foam", Japanese Patent Publication No. 3-597
3 "Continuous molding method of phenol resin foam",
169622 "Method for producing olefin resin open cell foam".

[0005] The techniques disclosed in these applications are summarized as follows: a foaming agent is mixed or kneaded with various foamed resin raw materials, and heated and foamed and fused in a continuous moving process to form a continuous molded article. Was to do.

[0006]

However, in the above-mentioned conventional example, the technique (a) is a so-called batch processing method, in which a molding process is performed for each predetermined amount. It was not something. For example,
In the case of the kneading extrusion molding method using an extruder, once the production is stopped, this mixed material is solidified in the apparatus, and it has been difficult to switch to the continuous production method.

[0007] In summary, the technique (b) is a method in which raw material beads are formed into a sheet shape and heated and foamed in a continuous moving process, and at the same time, a void for ensuring air permeability is also formed. At present, the operating conditions are complicated, for example, delicate control is required in consideration of the foaming state, the environmental temperature, the moving speed, and the like, and there are many variations in molded products.

[0008]

Therefore, the present invention has been made in view of the above-mentioned problems, and is intended to form a large number of communicating voids by fusing a part of surfaces of a foamed small lump foam with each other.
An object of the present invention is to provide a method of producing a continuous molded article of a gas-permeable / water-permeable foamed resin, which is provided with air permeability and water permeability and is continuously formed instead of a batch type.

[0009]

Means for Solving the Problems In order to achieve the above object, a method for producing a continuous molded article of a gas-permeable and water-permeable foamed resin according to the present invention is constituted as follows.

A large number of foams made of a thermoplastic resin are continuously supplied into a communicating partitioned mold having a conveying means, and a partial surface of each of the supplied foams is sequentially fused to each other. The method is characterized in that a continuous body having a large number of communicating voids is formed by the process.

The foam used here may be a foam obtained by foaming raw material beads at an appropriate expansion ratio, or a small-lumped foam of an existing product, for example, spherical, granular, square, or the like. Interlock shape, saddle shape, Shiba boat shape, S
It is also possible to use a bubble having a character shape or the like. Furthermore, a foam that has been formed into various shapes as a sheet, a block, a bar, or a cushioning material may be used as a small lump by means such as cutting or pulverization. That is, a so-called recycled product may be used as long as it is a foam made of a fusible thermoplastic resin, and the above-described various foams may be mixed and used.

In the above-mentioned manufacturing method, the foam supplied into the compartment mold may be further foamed and a partial surface of each foam may be sequentially fused together. The fusing means may be performed by a heating means.

[0013] In addition to the above-described manufacturing method, a continuous pressurization is performed from the inlet side in the compartment mold with a predetermined pressing force, and a compressive force is applied to the foam group in the compartment mold as it moves. You may do it. The application of the compressive force may be performed, for example, by moving the inside of the sectional mold configured so that the cross-sectional area in the sectional mold gradually decreases in the moving direction.

Still further, in addition to the above-described manufacturing method, a step of applying a coating material to a continuous body delivered from the partitioned mold is additionally provided.

[0015]

According to the above-mentioned manufacturing method, the air bubbles and the water-permeable foamed resin continuous molded article in which a large number of interconnected voids are formed by fusing some of the surfaces of the foam groups sent into the compartment mold with each other. (Hereinafter, abbreviated as “continuous molded body”) is continuously molded.

The fusion is adjusted by the addition of the pressing force and the compressive force, and the porosity and the compressive strength of the continuous body are adjusted. By moving the inside of the section mold configured such that the sectional area in the section mold gradually decreases in the moving direction, a compressive force is continuously applied.

[0017]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Next, an example of a specific apparatus for realizing a method for producing a continuous molded article according to the present invention will be described with reference to the drawings. FIG. 1 is a schematic view of the apparatus of the present embodiment.

The foams 2 are stored in a feeder 4, and are extruded forward from an extruder 5 configured so that the foams do not fuse and fuse with each other, and are supplied into a compartment mold 3. The outlet of the extruder 5 is connected in communication with the inlet of the section mold 3, and the extruded foam is supplied into the section mold 3 with a predetermined pressing force.

As the foam 2 used here, all foams produced by foaming a thermoplastic resin can be used. For example, polystyrene, polyethylene, acrylonitrile-based resin, polyamide-based resin, fluorine-based resin, polyester-based resin, or ether-based resin are widely used.

Further, these foams 2 are provided with an antistatic function, a conductive function, a flame-retardant function, a weather-resistant function, a fungicide-proof function, a crosslinked or colored one, and a talc, glass fiber, carbon fiber or the like. A material having various functions added, such as a material having a filler mixed therein, may be used. By using the foam 2 having such additional functions, these functions can be enjoyed when the continuous molded body 1 is formed.

Here, the shape of these foams 2 to be used does not need to be specially formed.
What is usually used as a small-lumped collecting buffer, for example, spherical, granular, S-shaped, chip-shaped,
May be used alone or in combination of two or more.

The size of the foam 2 depends on the extruder 5, but it can be about 0.5 mm to 100 mm, but preferably 2 mm to 20 mm.

Next, the space type of the partitioning mold 3 has a cylindrical shape having a rectangular cross section which communicates with each other, and upper and lower surfaces are constituted by belt conveyors 6 and 6 as conveying means with the same gradient which is vertically symmetrical. Thereby, the space cross-sectional shape is formed in a tapered shape that gradually decreases in the moving direction (arrow a). By the operation of the belt conveyors 6 arranged above and below, the foam 2 is conveyed, and a compressive force is applied as it moves.

The mechanism for applying the compressive force in accordance with this movement is not limited to this structure, and although not shown in the drawings, for example, the space may be shifted upward or downward or both in the moving direction. A configuration in which a plurality of changed rollers are arranged, and a compression force and a conveyance force are applied by sandwiching the rollers may be employed.

The partition mold 3 is placed in a heated atmosphere. As the heating means, a hot air heater 7 is used, which is arranged inside the upper and lower belt conveyors 6, 6 so that the hot air hits the group of the bubbles 2 through the air-permeable conveyor belt. ing. The temperature of the warm air at this time is set to a temperature at which the surface of the foam 2 melts.

With this configuration, the surface of the group of bubbles 2 moving in the partition mold 3 is slightly melted by hot air, and is compressed and fused together. The fusion state at this time is such that the entire surface of the foam 2 is not fused, but a part of the surface is fused to each other. As a result, a large number of gaps are formed between the foams 2, and since these are communicated with each other, connected voids that can pass not only air but also water are formed. The size of the communicating voids can be freely set depending on the amount of compressive force applied, but it is necessary that at least some surfaces of the bubbles 2 are fused to each other at least to the extent that they can be held as a continuous body. There is.

The applied compressive force depends on the pressing force from the extruder 5, the moving speed of the belt conveyor 6, and the
It is set by appropriately adjusting the reduction gradient of the cross-sectional area inside.

By the way, in the above-described embodiment, the partition type 3
The foam 2 to be supplied into the inside is formed by foam molding from foamed resin beads as a raw material, and the expansion ratio is appropriately selected from the product specifications and the requirement of the porosity. Also,
Even after supplying these foamed foams 2 to the compartment mold 3,
Further, foaming may be performed. In this case, the temperature environment in the partition mold 3 is set to a temperature at which foaming can be further performed.

Further, in the above-described embodiment, the fusion of the bubbles 2 is performed by blowing hot air. However, the present invention is not limited to this. It is widely applicable. For example, steam heating, ultrasonic heating, dielectric heating, or friction heating by vibration can be considered.

Next, the continuous molded product 1 discharged from the partition mold 3 is formed as a product even in this state, but it may have an additional function.
For example, when water resistance is given as an additional function, as shown in the figure, a spray nozzle 8 of a water resistant agent is arranged on a moving line of the continuous molded body 1, and thereby spreads to the surface of the foam 2 through a gap. In this way, the coating process of applying the waterproofing agent, the liquid removal process by the blowing means 9 after the coating process, and then the coating material drying process of moving in the hot air drying furnace 10 may be sequentially performed. In this embodiment, as a coating material having a water resistance function, for example,
Styrene / butadiene paint, acrylic paint, vinyl acetate paint, urethane paint, etc. are used. However, it is necessary to appropriately set the dilution ratio of the viscosity of the coating material to be applied in consideration of the clogging of the voids in the continuous molded body 1.

Although the above process is described with respect to the application of a waterproofing agent, the present invention is not limited to this. For example, the conductive function, the flame-retardant function, and the like described in the description of the additional function of the foam 2 can be used. A drug for addition may be applied.

[0032]

[Possibility of Another Embodiment] The conceptual diagram of the above embodiment is an example of realizing the manufacturing method of the present invention, and it is needless to say that the present invention is not limited to this.

That is, in the above-described embodiment, the continuous molded body manufactured by arranging the partition mold 3 in the horizontal direction moves in the horizontal direction. It may be arranged vertically and supplied with foam from above to form a continuous molded body in a substantially vertical descending direction. In this case, the pressing force and the compressing force may be applied only by the own weight of the foam without requiring the pressing force from the entrance (above) of the partition mold 3 or the compressive force applied to the side surface.

[0034]

Next, examples of the above-mentioned manufacturing method will be described. Table 1 shows Examples 1 to 3, and Table 2 shows Examples 4 to 6.
And Table 3 shows Examples 7 to 9.

[0035]

[Table 1]

[0036]

[Table 2]

[0037]

[Table 3] The following is a detailed description of a specific device based on Example 3 shown in Table 1 above.

First, beads of HA grade polystyrene manufactured by Sekisui Plastics Co., Ltd. (trade name: Eslen beads, particle size of about 1.8 mm) are prefoamed with steam of 0.15 kg gauge pressure and cured for 24 hours. Particle size 7.0 to 7.5
mm pre-expanded beads.

The pre-expanded beads were inserted into a biaxially different-direction rotating screw (flight outer diameter 25
0mmφ, flight interval 80mm, shaft base diameter 50mmφ)
At a feed rate of 3.85 cubic meters per hour using an extruder consisting of The compartment type used here has an entrance height of 53.5.
mm / outlet height 50.0 mm, frame length 600 mm, width 1,0 m, with vertically symmetric caterpillar-type push plate and two upper and lower hot air injection nozzles Using. The hot air from the hot air jet nozzle is 96
At a degree C, a hot air volume of 110 liters was injected per liter of foam. As a result, a continuous body having a width of 1.0 m and a thickness of 50 mm could be formed at a stroke speed of 3.60 cubic meters per hour.

Further, after the above-described steps, a coating step, a liquid removing step, and a drying step were passed. In the application process, a mixture of 75 parts by weight of an emulsion paint (trade name: Asuka II) manufactured by Kansai Paint Co., Ltd. and 25 parts by weight of dilution water was sprayed at a rate of 290 kg per hour.
Then, after passing through a draining step of the coating liquid, the coating liquid was passed through a 6 m-long, 80 ° C. hot air drying furnace as a drying step to produce a water-resistant continuous molded article.

As a result, the porosity after drying was 33.4%, and the compressive strength was 5%.
0.6 kg / cm2, 10% compression strain
0.9 kg / cm2, compressive strain 20%
/ Square centimeter.

[0042]

[Effect] Since the present invention is configured as described above,
A resin foam molded article having air permeability and water permeability can be continuously formed. Therefore, unlike the conventional batch processing method, it is possible to freely cut a long material of various lengths into a product, and to quickly produce an appropriate product in a necessary place at a necessary length. There are advantages that can be.
Moreover, because it has air permeability and water permeability, as a building material,
Various uses are found, such as as a construction material under the ground and as a cushioning material having a higher cushioning effect than a conventional non-permeable foamed resin block due to a large number of voids between the foams.

In the case where a small-agglomerated foam that is conventionally available as a cushioning material is used and fused, the equipment configuration and its control mechanism can be simplified, resulting in inexpensive manufacturing. There is an advantage that it can be mass-produced at a low cost.

[Brief description of the drawings]

FIG. 1 is a schematic view of an apparatus of the present embodiment. DESCRIPTION OF SYMBOLS 1 ... Continuous molding of air-permeable / water-permeable foamed resin ("continuous molding") 2 ... Foam 3 ... Partition type 4 ... Feeder 5 ... Extruder 6 ... Belt conveyor 7 ... Hot air heater 8 ... Injection nozzle 9 ... Blowing means 10 ... Hot air drying furnace

Claims (7)

[Claims] 1. A method according to claim 1, further comprising the steps of:
By continuously supplying a large number of foams made of thermoplastic resin, and by sequentially fusing some surfaces of the supplied foams, a continuous body having a large number of interconnected voids is formed. A method for producing a continuously molded air-permeable / water-permeable foamed resin, characterized by being molded. 2. The method for producing a continuously permeable foamed resin molded article according to claim 1, wherein the foam supplied into the partition mold is
A method for producing a continuously molded air-permeable and water-permeable foamed resin, wherein foaming is further performed and a partial surface of each foam is sequentially fused together. 3. The method for producing a continuously molded air-permeable and water-permeable foamed resin according to claim 1, wherein the fusion is performed by a heating means. 4. A method for producing a continuously molded water-permeable foamed resin according to claim 1, 2 or 3, wherein a continuous pressing is performed with a predetermined pressing force from an inlet side in the compartment mold. For producing a continuous molded article of a gas-permeable / water-permeable foamed resin. 5. In addition to the method for producing a water-permeable foamed resin continuous molded article according to claim 1, a compressive force is applied to a group of foams in the partition mold as the foamed body moves. A method for producing a continuous molded article of a gas-permeable and water-permeable foamed resin. 6. A compressive force is applied by moving in a section mold configured such that a cross-sectional area in the section mold gradually decreases in a moving direction. A method for producing the continuous molded article of the air-permeable / water-permeable foamed resin according to the above. 7. In addition to the method for producing a water-permeable foamed resin continuous molded article according to claim 2, a coating material is applied to the continuous article delivered from the compartment mold. A process for producing a continuous molded article of a gas-permeable and water-permeable foamed resin, comprising a step.