JP6851586B2 - Method for manufacturing a foam molded product composed of multiple layers - Google Patents

Description

The present invention relates to a method for producing a foam molded product composed of multiple layers, which can integrally mold a foam molded product in which a plurality of foam molded product layers are laminated with one molding mold.

Conventionally, in a wide range of fields such as packaging materials for various industrial products and fresh foods, interior materials for automobiles, and building materials, for example, foamed particles of polyolefin resin are molded so as to be fused to each other on substantially the entire surface. Molded bodies and foamed molded bodies molded so as to have gaps between the foamed particles so as to be point-fused to each other are widely used.

Recently, a foam composite molded body (for example, see Patent Document 1) in which a foam molded body layer having vibration damping properties and a foam molded body layer having breathability are laminated, and the surface of a core layer made of a foam molded body layer. Has been proposed, in which the above is laminated with a foam molded body layer having a specific composition and excellent fusion property (see Patent Document 2). In this way, when a plurality of foam molded product layers having different functions are laminated, each foam molded product layer exerts a unique effect, so that it is possible to provide an excellent material according to the intended use.
In addition, the applicant himself has developed a soundproofing material in which a non-breathable foam molded body layer and a breathable foam molded body layer are laminated, and has previously applied for a patent (see Patent Document 3).

However, in the conventional foam composite molded product, each foam molded product layer is molded separately and then bonded and integrated with an adhesive in a later step. Moreover, since each foam molded body layer is cut into a predetermined size and bonded to each other, there is a problem that the work is complicated and takes a long time. There is also a problem that the manufacturing cost is high.

Japanese Unexamined Patent Publication No. 11-42725 Japanese Patent No. 5829717 Japanese Patent No. 4079851

Therefore, it has been desired to develop a method for integrally molding a foam molded product in which a plurality of different foam molded product layers are laminated with one molding mold. However, in the foam molding process, heating by passing steam or heated air is desired. The process is indispensable, and if there is a foam molded product layer that does not have air permeability, it hinders the flow of steam, so there is a technical problem that it is not possible to integrally mold a multi-layered product in one molding mold. there were.
The present invention solves the above-mentioned conventional problems to obtain a foam molded product obtained by laminating a plurality of foam molded product layers having different non-breathable foam molded product layers and breathable foam molded product layers. It is an object of the present invention to provide a method for producing a foam molded product composed of multiple layers, which can be integrally molded with one molding mold instead of being bonded by secondary processing.

The present invention made to solve the above problems
Foam molding consisting of a multi-layer structure in which a first foam-molded body layer having a porosity of less than 5% and having no air permeability and a second foam-molded body layer having a porosity of 10 to 40% are laminated and integrated. It ’s a method of manufacturing the body.
The first breath that penetrates in the thickness direction by filling, heating, and cooling the raw material beads with the first pin for forming a breathing hole intruded into the primary cavity formed by the pair of fixed type and mobile type. A first foam molded body layer with holes is molded and
Next, after the first pin is retracted, the mobile mold is retracted together with the first foam molded body layer to form a secondary cavity between the fixed mold and the first foam molded body layer.
Next, the raw material beads are filled, heated, and cooled in the secondary cavity and inside the first breathing hole, and the heating / cooling medium is circulated through the first breathing hole to form a second foam molded product layer. This is a method for producing a foam molded product composed of multiple layers, which is characterized by molding the above, and this is the invention according to claim 1.

Further, according to a preferred embodiment, a first foam molded body layer having a porosity of less than 5% and having no air permeability, and second and third foam molding having a porosity of 10 to 40% having air permeability. It is a method for manufacturing a foam molded product composed of multiple layers in which body layers are laminated and integrated.
Raw material beads are filled, heated, and cooled to penetrate in the thickness direction with the first and second pins for forming breathing holes intruded into the primary cavity formed by the pair of fixed mold and mobile mold. The first foam molded body layer having the first breathing hole and the second breathing hole was formed, and
Next, after the first pin is retracted, the mobile mold is retracted together with the first foam molded body layer to form a secondary cavity between the fixed mold and the first foam molded body layer.
Next, the raw material beads are filled, heated, and cooled in the secondary cavity and inside the first breathing hole, and the heating / cooling medium is circulated through the first breathing hole to form a second foam molded product layer. Molded,
Next, after the second pin is retracted, only the mobile mold is retracted, leaving the first and second foam molded product layers in the fixed mold, and between the mobile mold and the first foam molded product layer. Form a tertiary cavity,
Next, the raw material beads are filled, heated, and cooled in the tertiary cavity and the inside of the second breathing hole, and the heating / cooling medium is circulated through the second breathing hole to form a third foam molded product layer. This is a method for producing a foam molded product composed of multiple layers, which is characterized by molding the above, and this is the invention according to claim 2.

According to another preferred embodiment, the first foam-molded body layer is molded so that the raw material beads made of foamed particles are fused to each other on substantially the entire surface, and the second and third foam-molded body layers are formed. , The raw material beads made of foamed particles can be molded so as to be point-fused to each other so as to have voids between the foamed particles, and this is the invention according to claims 3 and 4 .

In the invention according to claim 1, a first foam molded body layer having a first breathing hole penetrating in the thickness direction is molded, and a heating / cooling medium is circulated through the first breathing hole to form a second foam molding. Since the body layer is molded, the first foam-molded body layer having no breathability and the second foam-molded body layer having breathability can be laminated and integrated in the mold. Further, since the resin of the second foam molded body layer has entered the inside of the first breathing hole, the bond between the first foam molded body layer and the second foam molded body layer is further strengthened. Can be.

In the invention according to claim 2, a first foam molded body layer having a first breathing hole and a second breathing hole is molded, a second foam molded body layer is molded, and then heating is performed through the second breathing hole. Since the third foam molded body layer is formed by circulating the cooling medium, the second foam molded body layer having breathability and the second foam molded body layer having breathability are formed on both sides of the first foam molded body layer having no breathability. The foam molded product layer of 3 can be laminated and integrated in the mold. Further, since the resin of the third foam molded body layer has entered the inside of the second breathing hole, the first foam molded body layer, the second foam molded body layer, and the third foaming are formed. The bond between the molded body layers can be made stronger.

In the invention according to claim 3, the foam-molded article is composed of a multi-layer in which a first foam-molded body layer having no breathability and a second foam-molded article layer having breathability are laminated and integrated. In the invention according to the invention, it is possible to obtain a foam molded product composed of a first foam molded product layer having no breathability and a multi-layered layer in which the second and third foam molded product layers having breathability are laminated and integrated.

It is a perspective view of the foam molded body composed of two layers obtained by the manufacturing method of this invention. It is an enlarged cross-sectional view which shows the main part of FIG. It is a perspective view of the foam molded body composed of 3 layers obtained by the manufacturing method of this invention. It is an enlarged cross-sectional view which shows the main part of FIG. It is explanatory drawing which shows the filling process of the raw material beads in the primary cavity in the molding process of the foam molded body composed of two layers. It is explanatory drawing which shows the raw material return process of FIG. It is explanatory drawing which shows the heating process of FIG. It is explanatory drawing which shows the cooling process of FIG. It is explanatory drawing which shows the process of retracting the 1st pin of FIG. It is explanatory drawing which shows the process of forming a secondary cavity. It is explanatory drawing which shows the process of filling raw material beads into a secondary cavity. It is explanatory drawing which shows the raw material return process of FIG. It is explanatory drawing which shows the heating process of FIG. It is explanatory drawing which shows the cooling process of FIG. It is explanatory drawing which shows the process of retreating the mobile type of FIG. It is explanatory drawing which shows the product take-out process of FIG. It is explanatory drawing which shows the filling process of the raw material beads in the primary cavity in the molding process of the foam molded body composed of three layers. It is explanatory drawing which shows the raw material return process of FIG. It is explanatory drawing which shows the heating process of FIG. It is explanatory drawing which shows the cooling process of FIG. It is explanatory drawing which shows the process of retracting the 1st pin of FIG. It is explanatory drawing which shows the process of forming a secondary cavity. It is explanatory drawing which shows the process of filling raw material beads into a secondary cavity. It is explanatory drawing which shows the raw material return process of FIG. It is explanatory drawing which shows the heating process of FIG. It is explanatory drawing which shows the cooling process of FIG. It is explanatory drawing which shows the process of forming a tertiary cavity. It is explanatory drawing which shows the process of retracting the 2nd pin of FIG. It is explanatory drawing which shows the process of filling raw material beads into a tertiary cavity. It is explanatory drawing which shows the raw material return process of FIG. It is explanatory drawing which shows the heating process of FIG. It is explanatory drawing which shows the cooling process of FIG. It is explanatory drawing which shows the product taking-out process of FIG.

Hereinafter, preferred embodiments of the present invention will be shown with reference to the drawings.
In the foam molding machine used in the present invention, raw material beads are filled in cavities formed by a fixed mold and a mobile mold, and then a heating medium or a cooling medium is supplied from a chamber chamber on the back side of each mold to heat and cool. It is a general molding machine that processes and molds a foam molded product (not shown).
FIG. 1 is a perspective view of a two-layer foam molded product obtained by the production method of the present invention, FIG. 2 is an enlarged cross-sectional view of a main part of FIG. 1, and FIG. 3 is a view obtained by the production method of the present invention3. A perspective view of the foam molded product composed of layers, FIG. 4 is an enlarged cross-sectional view of a main part of FIG. 5 to 16 are explanatory views showing a molding process of a foam molded product composed of two layers, and FIGS. 17 to 34 are explanatory views showing a molding process of a foam molded product composed of three layers.

In FIGS. 1 to 4, 1 is a multi-layer foam molded product, 1a is a first foam molded product layer, 1b is a second foam molded product layer, and 1c is a third foam molded product layer.
The first foam-molded body layer 1a is formed so that raw material beads made of foamed particles are fused to each other on substantially the entire surface, and is not breathable. Further, the second foam-molded body layer 1b and the third foam-molded body layer 1c are formed so that the raw material beads made of the foamed particles are point-fused to each other so as to have voids between the foamed particles. , Breathable.

As described above, the multi-layer foam molded product of the present invention is composed of two layers in which a first foam molded product layer 1a having no breathability and a second foam molded product layer 1b having breathability are laminated and integrated. It will be. Alternatively, the first foam molded body layer 1a having no breathability is used as a core material, and the second foam molded body layer 1b having breathability and the third foam molded body layer 1c having breathability are laminated on both sides thereof. It consists of three integrated layers.

The porosity of the first foam molded product layer 1a is preferably less than 5%, and the porosity of the second and third foam molded product layers 1b and 1c is preferably 10 to 40%. This is because if the porosity of the first foam molded product layer 1a is 5% or more, it cannot be said that the first foam molded product layer 1a does not have air permeability. Further, if the porosity of the second and third foam molded product layers 1b and 1c is less than 10%, it cannot be said that the product has sufficient air permeability, while if it is larger than 40%, the strength of the molded product is weakened. Because.
As described above, by forming a multi-layer molded body composed of different layers, it is possible to provide a composite that exhibits the characteristics of each layer and exerts a plurality of effects that have never existed before.

The first to third foam molded product layers are made of a thermoplastic resin. Specifically, those made of polystyrene-based resin, polyethylene-based resin, polypropylene-based resin, polyolefin-based resin and the like are preferable. Alternatively, the resin may consist of a mixture of two or more of these resins. From the viewpoint of moldability, mechanical strength, fusion property and the like, polystyrene-based resin, polyethylene-based resin, or a mixed resin thereof is particularly preferable.

(Manufacturing method of foam molded product consisting of two layers)
Next, a method for producing the foam molded product composed of two layers will be described with reference to FIGS. 5 to 16.
In the figure, 2 is a concave fixed type, 3 is a convex moving type, and 4a is a primary cavity formed by the pair of fixed types 2 and the moving type 3. Reference numeral 5 denotes a filler for raw material beads provided on the back surface of the fixed mold 2, and reference numeral 6a is a first pin for forming a breathing hole. Unlike the one shown in the drawing, the fixed mold 2 can be made convex and the movable mold 3 can be made concave, and the filler 5 and the first pin 6a can be arbitrarily provided on the mobile mold 3 side.

First, as shown in FIG. 5, the primary cavity 4a (thickness: t1) formed by the pair of fixed molds 2 and the mobile mold 3 is filled with the first pin 6a for forming a breathing hole intruded. Fill the raw material beads from the vessel 5. After the filling of the raw material beads is completed, as shown in FIG. 6, the excess raw material beads in the filler 5 are returned to the raw material hopper (not shown). The first pin 6a can be moved freely by, for example, an air cylinder 7.

Next, as shown in FIG. 7, a heating medium (heated steam) is supplied to the chamber chamber on the back side of the mold to perform heat treatment, and the raw material beads made of foamed particles are fused to each other on substantially the entire surface. After that, as shown in FIG. 8, a cooling medium (cooling air) is supplied to the chamber chamber on the back side of the mold to perform a cooling treatment, and the first foam molded body layer 1a (thickness: t1) having no air permeability is performed. ) Is molded. This heating / cooling treatment process is basically the same as the conventional foamed resin molding process.

Next, as shown in FIG. 9, the first pin 6a is retracted to a position where its tip is flush with the bottom surface of the fixed mold 2. As a result, the first breathing hole 8a penetrating in the thickness direction is formed in the first foam molded body layer 1a. After that, as shown in FIG. 10, the mobile mold 3 is retracted together with the first foam molded body layer 1a, and a secondary cavity 4b (thickness: t2) is placed between the fixed mold 2 and the first foam molded body layer 1a. ) Is formed.

Next, as shown in FIG. 11, the secondary cavity 4b is filled with the raw material beads from the filler 5. At this time, the raw material beads are also filled in the first breathing hole 8a. After the filling of the raw material beads is completed, as shown in FIG. 12, the excess raw material beads in the filler 5 are returned to the raw material hopper (not shown).

Next, as shown in FIG. 13, a heating medium (heated steam) is supplied to the chamber chamber on the back side of the mold to perform heat treatment, and the raw material beads made of foamed particles are mutually arranged so as to have voids between the foamed particles. Dot fusion to. At this time, the first foam molded body layer 1a having no air permeability is interposed, but the heating medium flows between the chamber chambers on the back surface side of the mold through the first breathing hole 8a, so that the heat treatment is sufficient. It can be performed.
After that, as shown in FIG. 14, a cooling medium (cooling air) is supplied to the chamber chamber on the back side of the mold to perform the cooling process. At this time as well, the cooling medium flows between the chamber chambers on the back surface side of the mold through the first breathing hole 8a, so that the cooling process can be sufficiently performed.
As a result, the first foam-molded body layer 1a having no breathability and the second foam-molded body layer 1b having breathability are laminated and integrated, and the second breathing hole 8a is filled with the second foam-molded body layer 1b. Since the foam-molded resin of the above is in the state, a foam-molded body composed of two layers more firmly bonded is formed.

Then, as shown in FIG. 15, after the mobile mold 3 is retracted, as shown in FIG. 16, the foam molded product is discharged to the outside of the fixed mold 2 by the operation of the eject pin (not shown). It will be.
In this way, a foam molded product composed of a multi-layer in which a first non-breathable foam molded product layer 1a and a second foam molded product layer 1b having breathability are laminated and integrated is produced by a foam molding machine. It can be manufactured in a cycle, and it can be molded in a shorter time than the conventional manufacturing method in which separately molded products are bonded and integrated with an adhesive in a subsequent process.

(Manufacturing method of foam molded product consisting of 3 layers)
Next, a method for producing the foam molded product composed of three layers will be described with reference to FIGS. 17 to 34.
As shown in FIG. 17, a state in which the first pin 6a and the second pin 6b for forming a breathing hole are invaded into the primary cavity 4a (thickness: t1) formed by the pair of fixed molds 2 and the mobile mold 3. Then, the raw material beads are filled from the filler 5. After the filling of the raw material beads is completed, as shown in FIG. 18, the excess raw material beads in the filler 5 are returned to the raw material hopper (not shown). The first pin 6a and the second pin 6b can be moved freely by, for example, an air cylinder 7.

Next, as shown in FIG. 19, a heating medium (heated steam) is supplied to the chamber chamber on the back side of the mold to perform heat treatment, and the raw material beads made of foamed particles are fused to each other on substantially the entire surface. After that, as shown in FIG. 20, a cooling medium (cooling air) is supplied to the chamber chamber on the back side of the mold to perform a cooling treatment, and the first foam molded body layer 1a (thickness: t1) having no air permeability is performed. ) Is molded. This heating / cooling treatment process is basically the same as the conventional foamed resin molding process.

Next, as shown in FIG. 21, the first pin 6a is retracted to a position where its tip is flush with the bottom surface of the fixed mold 2. The second pin 6b is left in the primary cavity 4a. As a result, the first breathing hole 8a penetrating in the thickness direction is formed in the first foam molded body layer 1a. After that, as shown in FIG. 22, the mobile mold 3 is retracted together with the first foam molded body layer 1a, and the secondary cavity 4b (thickness: t2) is placed between the fixed mold 2 and the first foam molded body layer 1a. ) Is formed.

Next, as shown in FIG. 23, the raw material beads are filled in the secondary cavity 4b from the filler 5. At this time, the raw material beads are also filled in the first breathing hole 8a. After the filling of the raw material beads is completed, as shown in FIG. 24, the excess raw material beads in the filler 5 are returned to the raw material hopper (not shown).

Next, as shown in FIG. 25, a heating medium (heated steam) is supplied to the chamber chamber on the back side of the mold to perform heat treatment, and the raw material beads made of foamed particles are mutually arranged so as to have voids between the foamed particles. Dot fusion to. At this time, the first foam molded body layer 1a having no air permeability is interposed, but the heating medium flows between the chamber chambers on the back surface side of the mold through the first breathing hole 8a, so that the heat treatment is sufficient. It can be performed.
After that, as shown in FIG. 26, a cooling medium (cooling air) is supplied to the chamber chamber on the back side of the mold to perform the cooling process. At this time as well, the cooling medium flows between the chamber chambers on the back surface side of the mold through the first breathing hole 8a, so that the cooling process can be sufficiently performed.
As a result, the first foam molded body layer 1a having no breathability and the second foam molded body layer 1b having breathability are laminated and integrated, and further, a second foam molded body layer 1b is formed in the first breathing hole 8a. Since the foam-molded resin is contained in the foam-molded product, a foam-molded product composed of two layers in a more firmly bonded state is molded.

Next, as shown in FIG. 27, the foam molded body composed of two layers is left in the fixed mold 2 and only the mobile mold 3 is retracted, and a tertiary cavity is formed between the mobile mold 3 and the first foam molded body layer 1a. Form 4c (thickness: t3). After that, as shown in FIG. 28, the second pin 6b is retracted to a position where the tip portion thereof is flush with the bottom surface of the fixed mold 2 to form a second breathing hole 8b penetrating in the thickness direction.

Next, as shown in FIG. 29, the raw material beads are filled into the tertiary cavity 4c from the filler 9 on the mobile side. At this time, the raw material beads are also filled in the second breathing hole 8a. After the filling of the raw material beads is completed, as shown in FIG. 30, the excess raw material beads in the filler 9 are returned to the raw material hopper (not shown).

Next, as shown in FIG. 31, a heating medium (heated steam) is supplied to the chamber chamber on the back side of the mold to perform heat treatment, and the raw material beads made of foamed particles are mutually arranged so as to have voids between the foamed particles. Dot fusion to. At this time, the first foam molded body layer 1a having no air permeability is interposed, but the heating medium flows between the chamber chambers on the back surface side of the mold through the second breathing hole 8b, so that the heat treatment is sufficient. It can be performed.
After that, as shown in FIG. 32, a cooling medium (cooling air) is supplied to the chamber chamber on the back side of the mold to perform the cooling process. At this time as well, the cooling medium flows between the chamber chambers on the back surface side of the mold through the second breathing hole 8b, so that the cooling process can be sufficiently performed.
As a result, the first foam molded body layer 1a having no air permeability is used as the central layer, and the second foam molded body layer 1b and the third foam molded body layer 1c having air permeability on both sides thereof are laminated and integrated. Will be done. Moreover, since the second foam-molded resin is contained in the first breathing hole 8a and the third foam-molded resin is contained in the second breathing hole 8b, the resin is stronger. A foam molded body composed of three layers joined to the above will be molded.

Then, as shown in FIG. 33, after the mobile mold 3 is retracted, the foam molded product is discharged to the outside of the fixed mold 2 by the operation of the eject pin (not shown).
In this way, the first foam molded body layer 1a having no air permeability, the second foam molded body layer 1b having breathability located on both sides thereof, and the third foam molded body layer 1c are laminated and integrated. The foam molded product consisting of the three layers can be manufactured in one cycle by a foam molding machine, which is more than the conventional manufacturing method in which separately molded products are bonded and integrated with an adhesive in a subsequent process. It became possible to mold easily and in a short time.

The size of the inner diameters of the first breathing hole and the second breathing hole can be arbitrarily set according to the application of the multilayer foam molded product and various required characteristics. Further, the mounting pitch and mounting range of the first breathing hole and the second breathing hole can be arbitrarily set according to the application and various required characteristics.
Furthermore, it goes without saying that by repeating the manufacturing process described above, a foam molded product having four or more layers can be manufactured.

1 Foam molding 1a First foam molding layer 1b Second foam molding layer 1c Third foam molding layer 2 Fixed type 3 Mobile type 4a Primary cavity 4b Secondary cavity 4c Tertiary cavity 5 Filler 6a 1st pin 6b 2nd pin 7 Air cylinder 8a 1st breathing hole 8b 2nd breathing hole 9 Filler

Claims (4)

Foam molding consisting of a multi-layer structure in which a first foam-molded body layer having a porosity of less than 5% and having no air permeability and a second foam-molded body layer having a porosity of 10 to 40% are laminated and integrated. It ’s a method of manufacturing the body.
The first breath that penetrates in the thickness direction by filling, heating, and cooling the raw material beads with the first pin for forming a breathing hole intruded into the primary cavity formed by the pair of fixed type and mobile type. A first foam molded body layer with holes is molded and
Next, after the first pin is retracted, the mobile mold is retracted together with the first foam molded body layer to form a secondary cavity between the fixed mold and the first foam molded body layer.
Next, the raw material beads are filled, heated, and cooled in the secondary cavity and inside the first breathing hole, and the heating / cooling medium is circulated through the first breathing hole to form a second foam molded product layer. A method for producing a foam molded product composed of multiple layers, which comprises molding. From a multilayer in which a first foam molded body layer having a porosity of less than 5% and having no air permeability and a second and third foam molded body layers having a porosity of 10 to 40% are laminated and integrated. This is a method for manufacturing a foam molded product.
Raw material beads are filled, heated, and cooled to penetrate in the thickness direction with the first and second pins for forming breathing holes intruded into the primary cavity formed by the pair of fixed mold and mobile mold. The first foam molded body layer having the first breathing hole and the second breathing hole was formed, and
Next, after the first pin is retracted, the mobile mold is retracted together with the first foam molded body layer to form a secondary cavity between the fixed mold and the first foam molded body layer.
Next, the raw material beads are filled, heated, and cooled in the secondary cavity and inside the first breathing hole, and the heating / cooling medium is circulated through the first breathing hole to form a second foam molded product layer. Molded,
Next, after the second pin is retracted, only the mobile mold is retracted, leaving the first and second foam molded product layers in the fixed mold, and between the mobile mold and the first foam molded product layer. Form a tertiary cavity,
Next, the raw material beads are filled, heated, and cooled in the tertiary cavity and the inside of the second breathing hole, and the heating / cooling medium is circulated through the second breathing hole to form a third foam molded product layer. method for producing a foamed molded article comprising the multilayer, characterized in that shaping the. The first foam-molded body layer is formed so that the raw material beads made of foamed particles are fused to each other on substantially the entire surface, and in the second foam-molded body layer, the raw material beads made of foamed particles are gaps between the foamed particles. The method for producing a foamed molded article composed of multiple layers according to claim 1, wherein the foamed molded article is molded so as to have a point fusion with each other. The first foam-molded body layer is formed so that the raw material beads made of foamed particles are fused to each other on substantially the entire surface, and the second and third foam-molded body layers are formed by foaming the raw material beads made of foamed particles. The method for producing a foamed molded product composed of multiple layers according to claim 2, wherein the foam molded products are molded so as to have gaps between them so as to be point-fused to each other.

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