JPH05200890A - Reinforced foam and method for producing the same - Google Patents

Abstract

(57) [Summary] (Modified) [Objective] To provide a reinforced foam capable of remarkably improving the fracture resistance and splash resistance of the foam, and a method for producing the same. A reinforced foam in which a entangled sheet of fiber / metal mesh is disposed in at least an inner layer of the foam, the fiber being mainly composed of an adhesive component and a strong component, and a composite fiber 1 and / or a composite yarn. And a reinforced foam in which the entangled body sheet and the foam are bonded and integrated via an adhesive component of fibers. Further, a entangled body sheet in which a composite fiber and / or a composite yarn mainly composed of a metal mesh and an adhesive component and a strong component is entangled is disposed in a mold having a desired shape, and a material having a latent foaming property is formed in the mold. The space portion is filled and heated, and at the same time as foam molding, the adhesive component of the fiber is thermally deformed and / or melted, and the entangled body is bonded and integrated at least in the foam inner layer portion.

Description

Detailed Description of the Invention

[0001]

FIELD OF THE INVENTION This invention relates to reinforced foams.
More specifically, the present invention relates to a foam body in which a specific entangled body sheet made of a fiber / metal mesh is bonded and integrated to an inner layer of the foam body to be reinforced, and a method for producing the foam body.

[0002]

2. Description of the Related Art Conventionally, polystyrene-based foams are small in deformation against external force and have excellent shape retention and dimensional stability, so that they are suitable for packaging and packing electric appliances and precision equipment, cooler boxes, heat insulating building materials, etc. It has been widely used.

However, while the polystyrene foam has many advantages as described above, it is extremely brittle against external stress such as impact or bending, and may be cracked by slight deformation.
It has a drawback that it is easily broken and leads to the total destruction of the foam. Therefore, it has been considered as a material that is not suitable for a portion that is subjected to a strong impact force, bending, or twisting.

In order to reinforce the polystyrene foam, a method of mixing fibers to reinforce the polystyrene foam has been proposed (Japanese Patent Publication No. 47-28097 and Japanese Patent Publication No. 48-100471). ), Since the reinforcing fibers and the foam are poorly integrated, a substantial reinforcing effect cannot be obtained, and the inventions described in those publications cannot be said to be preferable methods. In addition, there is a proposal to combine it with plastic, but although some effect on strengthening is recognized, it is said that if it is subjected to a large bending action, the plastic itself will be broken or the plastic surface will be hard and the buffering property will be poor. There was a flaw.

[0005]

In view of the above-mentioned problems, an object of the present invention is to provide a reinforced foam capable of remarkably improving the fracture resistance and the splash resistance of the foam and a method for producing the same. is there.

[0006]

In order to achieve the above object, the present invention has the following constitution.

That is, the reinforced foam of the present invention is a reinforced foam in which a entangled sheet of fiber / metal mesh is disposed in at least the inner layer of the foam, and the fibers are mainly an adhesive component and a strong component. Composite fiber consisting of /
Alternatively, it is a composite yarn, which is a reinforced foam characterized in that the entangled body sheet and the foam are bonded and integrated via an adhesive component of the fiber.

The method for producing a reinforced foam of the present invention is
A entangled body sheet in which composite fibers and / or composite yarns mainly composed of a metal mesh and an adhesive component and a strong component are entangled is disposed in a mold having a desired shape, and a material having a latent foaming property is provided in the mold space portion. The method for producing a reinforced foam, characterized in that the entangled body is adhered and integrated at least in the inner layer of the foam by heating and heating to heat and deform the adhesive component of the fiber to heat and / or melt the same. Is.

Alternatively, the method for producing a reinforced foam of the present invention comprises the step of extruding a molten polymer / foaming agent mixture from an extruder to atmospheric pressure, and forming a foam which can be expanded by vaporizing the foaming agent, or after foaming. A metal mesh and a entangled body sheet in which a composite fiber and / or a composite yarn mainly composed of an adhesive component and a strong component are entangled between a plurality of sheets of the body, and the adhesive component of the fiber is thermally deformed and / or melted to form a foam. The method for producing a reinforced foam is characterized in that the entangled body is bonded and integrated to the inner layer of the.

[0010]

The present invention will be described in detail below. TECHNICAL FIELD The present invention relates to a reinforced foam which is adhesively integrated with a specific entangled body sheet in which a metal mesh, a composite fiber and / or a composite yarn are entangled in at least an inner layer of the foam, and a manufacturing method thereof.

More specifically, the specific entangled body sheet referred to in the present invention is a composite fiber comprising at least two components, an adhesive component capable of favorably adhering to a foam on a metal mesh and a strong component having high tenacity. And / or a metal mesh / fiber entangled sheet in which composite yarns are intertwined,
Such an entangled sheet is a sheet-like sheet in which the constituent fibers themselves are entangled with each other, and the fibers are entangled with each other by intruding the fibers into the eyes of the metal mesh. The metal mesh / fiber entangled sheet is adhered to the inner layer of the foam in a planar manner to achieve good adhesion and integration with the foam, and high resistance of the metal mesh and sufficient deformation resistance due to low elongation. It is possible to obtain a foam that is exerted and has good mechanical performance.

The present inventors have already filed Japanese Patent Application No. 3-319.
No. 125 has filed an application relating to a reinforced foam which is adhesively integrated with a specific entangled body in which a metal mesh and composite fibers and / or composite threads are entangled on at least one surface of the foam, and a method for producing the same. However, the present invention is one in which the entangled body is integrally bonded to the surface of the foam,
In terms of strengthening, a remarkable effect can be exhibited. However, since there is a entangled body containing a hard metal mesh on the surface of the foam, the reinforcing foam as a whole has a cushioning property, but the surface is inferior in cushioning property as compared with the conventional foam. It was a thing.

In the reinforced foam of the present invention, the fiber portion of the entangled body sheet, which has good adhesiveness, is adhered to the inner layer of the foam in a planar shape, and therefore, when subjected to external stress, it has excellent characteristics of a metal mesh. Deformation resistance and high strength can work effectively,
Deformation and defects do not occur easily, and even if defects occur, the propagation of fracture is stopped by the metal mesh structure part, so that total destruction does not occur, and the foam surface has a conventional foam Therefore, it has a feature that it also has an excellent cushioning property. Needless to say, the present invention requires that the entangled body sheet be present as an integrated adhesive body in the inner layer of the foam. I do not care. In this case, higher strengthening is achieved, which is preferable.

That is, the reinforced foam of the present invention will not be broken unless it is subjected to a stress enough to cut the metal mesh. Further, depending on the disposition condition of the entangled body, it is possible to obtain a waterproofing effect by forming a film of the adhesive component.

The "metal mesh" referred to in the present invention is composed of various high-strength metal components and has a large number of through holes in the sheet-like surface, and is particularly limited as long as it satisfies such requirements. Not done. That is, the material is made of steel and non-ferrous metal material, pure iron, carbon steel, special steel, cast iron and cast steel for steel material, aluminum, magnesium, titanium, zinc, nickel, copper for non-ferrous metal material,
Lead, tin and alloys thereof, and used in any one or more of them. In addition, such forms include metal laths such as flat laths, cobras, corrugated laths, rib laths, wide laths (wire metal), high laths, composite laths, expanded metals, and their lath sheets, rhombus nets,
Kikko net, plain weave net, crimp net, twill net, twill weave net,
Wire mesh such as tatami mesh and various punching metals are applied. These wire diameter, mesh, mesh and porosity are appropriately selected according to the purpose and application. The metal mesh may be any fiber / metal mesh entangled body sheet in which a part of the entangled fibers may substantially exist in the through hole, and is not particularly limited to the above-mentioned one. .

The foam used in the method of the present invention is, for example, polystyrene, styrene / ethylene copolymer, acrylonitrile / styrene copolymer, bead molding or extrusion molding of polystyrene resin such as ABS resin. The foamed molded article or the raw material thereof can be preferably applied. In addition, other various resins such as polyethylene, polypropylene, phenol, polyurethane, polyester, urea, polyvinyl chloride, silicone, epoxy, polyimide and melamine can be applied.

The preferred form of the conjugate fiber is a core / sheath type fiber, a bimetal type fiber, a multi-layered joint type fiber, a radial multi-layered type fiber or the like, and among them, many sheath components are contained in the sheath component. A multi-core / sheath type composite fiber which is a fiber having a structure is preferable. For example, they are represented by polymer array fibers, mixed spun fibers and the like.

FIG. 1 to FIG. 7 are schematic cross-sectional schematic model views showing model embodiments of the conjugate fiber used in the present invention.

In such a composite fiber, the adhesive component is preferably arranged on the outer periphery or outer shell of the composite fiber. For example, in the core / sheath type composite fibers as shown in FIGS. 1, 2 and 3, it is preferable to arrange them in the sheath component. Further, in the bimetal type or multi-layer bonding type composite fiber as shown in FIGS. 4, 5, 6 and 7, it may be arranged in any component, but it is arranged in a portion having a large exposed area to the outside. It is more effective and preferable. In these figures, 1 is a composite fiber, 2'is a core component, and 3 is a sheath component.

The thickness of the composite fiber is not particularly limited as long as it is suitable as a fiber entangled body or a reinforcing material for its specific use, and is generally 0.1 to 1000 for the composite fiber. The range of denier is suitable, and in the multi-core / sheath type composite fiber, the thickness of the core fiber is usually preferably about 1/3 to 1/1000 of that of the composite fiber, and
The number of cores in the composite fiber is preferably in the range of 3 to 10000, and particularly preferably 10 to 1000.

As the adhesive component in the composite fiber, it is important that it is thermally deformed or melted by heating so as to have high adhesiveness with the foam.
Alternatively, it is preferable that B is satisfied. That is, A: a polymer containing the same monomer units as the foam, B: a polymer having good adhesiveness and compatibility with the foam, and especially A is preferable, but the foam is Even if it does not contain the same monomer unit as above, the present invention can be sufficiently achieved as long as the anchor effect or the like acts between the foam and the foam by heat deformation or melting to achieve preferable adhesion. The heat distortion temperature of the adhesive component is preferably lower than the heat distortion temperature of the foam by at least 10 ° C or more. Such preferable examples include a polystyrene copolymer obtained by copolymerizing styrene with a higher alcohol ester of acrylic acid or methacrylic acid, a polyester copolymer having an acid component of terephthalic acid / isophthalic acid, and a glycol component of ethylene glycol. ..

On the other hand, as a strong component, polyesters typified by polyethylene terephthalate, polyamides typified by nylon 6, nylon 66, aramids, other polyarylate, polyacrylonitrile, polyethylene, polypropylene, polyvinyl alcohol,
It is possible to apply polymers having various spinnability such as polyurethane and copolymer modified products thereof or a mixture of other components. Depending on the foam type from these polymer groups, One kind or two or more kinds of polymers are used depending on the purpose and application of the foam.

Further, in the above description, the case of the composite fiber obtained by the composite spinning has been described, but the present invention is not limited to the case of using such a composite fiber, and the core component or It is also possible to use a composite yarn such as a sheath component, or a mixed yarn (including a twisted yarn) made of fibers made of a polymer described as an adhesive component or a strong component. That is, in the present invention, a composite yarn using a combination of fibers or yarns made of an adhesive component and fibers or yarns made of a strong component may be used.

Further, in the present invention, by coating the metal mesh with the above-mentioned mainly adhesive component resin or similar resin, it is more preferable to bond and integrate the metal mesh and the foam or the metal mesh and the fiber. This is an effective means for increasing the above, and is preferable.

The form of the fibers may be any of cotton-like materials (short fibers) and long fibers (filaments), and these may be used in whole or in part to produce web-like materials, non-woven fabrics, woven fabrics and knitted fabrics. , A net-sheet-shaped material or the like, or a composite material thereof, or the like is used. It is preferable that a part of the fiber exists in the through hole of the metal mesh and can connect the front and back of the metal mesh. The basis weight of the fiber portion, the texture, the use of threads, etc. are not particularly limited. However, in order to create a structure in which the fibers enter the metal mesh structure and are entangled with each other, not only a strong structure structure, but also a cotton-like material, a non-woven fabric or the like and a composite material such as a woven fabric, a knitted fabric or a net sheet-like substance. Is preferably used.

One of the typical methods for producing an entangled body sheet in the present invention is to form a short fiber or long fiber non-woven web into a sheet by using a card, a cross wrapper, a random web or the like. It is performed by laminating metal meshes and entwining them with each other by needle punching and / or water jet punching. Such punching may be performed on either one side or both sides, and the method or degree of other punching is not particularly limited, and may be performed by a conventionally known method.

As an example of a method for adhering and integrating the entangled body sheet and the foam, one is to arrange the entangled body in a mold having a desired shape, and to form various latent foams in the space of the mold. Formable material, for example, material such as expandable polymer beads is filled and heated by supplying steam or hot air to heat-deform and / or melt the adhesive component of the fiber simultaneously with foam molding,
It is performed by bonding and integrating an entangled body to a part or the whole of the surface of the foam.

Further, the present invention is not limited to the foam formed by the in-mold foam molding method in the mold as described above,
It can also be applied in extruded foam by using an extruder. As an example of the method, a foaming agent is mixed in a molten polymer, and the mixture is extruded under pressure from an extruder at atmospheric pressure to foam by foaming the foaming agent to form a foam, or after the foaming. Laminate the body and confounding sheet (hereinafter,
This is carried out by a method in which the adhesive component of the fibers is thermally deformed and / or melted by "lamination treatment" to bond and integrate the entangled body with the inner layer of the foam. In this case, the extruded foam is preferably formed immediately after extrusion and by laminating and adhering the foam / entangled sheet while the temperature is higher than the heat distortion temperature of the adhesive component of the composite fiber. Of course, also in the in-mold foam molding method and the extrusion foam molding method, the entangled body sheet existing in the inner layer of the foam may be a single layer or a plurality of layers.

In the metal mesh, if the area occupied by the through holes is large, the fibers are laminated on the front and back of the metal mesh and heat-treated or pressure-contacted with the heating body, even if the fiber-metal mesh is not entangled. By doing so, there may be a case where the front and back fibers are adhered to each other to form a bridge structure in the through hole, but of course, such a case where the fibers are fused to each other to form an entangled structure can be preferably used. In addition, disposing fibers / metal mesh / unentangled body of fibers or unentangled body of fiber / metal mesh in the foam inner layer, and performing entangling and adhesive integration at once by foaming treatment or lamination treatment. You can also

Such treatment heat-deforms or melts the adhesive component so that it can sufficiently adhere to the foam, does not significantly deform or melt the foam, and does not reduce the high strength of the strong component. It is preferable to carry out under the range of conditions.

The foam obtained according to the present invention is used for construction and civil engineering such as road mud-preventing materials, various civil engineering materials, partitions for offices, etc. It can be preferably applied to the field. In addition, the heat insulation industry, vehicle fields such as automobile interior materials, packaging and
It can also be applied to the packing field, transportation pallets such as forklift trucks and containers, transportation and transportation fields such as containers, and sports and miscellaneous goods fields without auxiliary materials. In particular, since it has a higher level of impact resistance and superior cushioning properties as compared with the conventional reinforced foam, it can be preferably used for a shock absorbing plate or a vehicle bumper for protecting oneself from a vehicle collision accident. Further, it can be preferably used as a concrete form or a heat insulating material that also serves as a concrete form, by taking advantage of the good bending resistance.

[0032]

The present invention will be described in more detail with reference to the following examples.

In the examples, all "percentages" are by weight.

Example 1 As a composite fiber, a polymer array fiber having a sheath component of 80 parts by weight of styrene / 20 parts by weight of 2-ethylhexyl acrylate copolymer and a core component of nylon 6 (fiber length: 51
mm, number of islands: 36, denier of composite fiber: 3d), a web was produced through the steps of card and cross wrapper, and then needle punching was performed to produce two nonwoven fabrics. In the middle, 10 mesh, wire number 25, wire diameter 0.
A plain weave wire mesh made of stainless steel having a size of 50 mm and an opening of 2.0 mm was inserted, and further water jet punched to fabricate fibers forming the nonwoven fabric and an entangled body sheet in which the fibers and the wire mesh were entangled with each other.

Using the polystyrene foam molding machine, after disposing the entangled body sheet in the center of the mold space, expandable polystyrene beads are filled in the upper space part and the lower space part of the mold and steam is supplied. Thus, a reinforced foam body in which the foam-molded and entangled body was adhered and integrated with the inner layer of the foam body was obtained.

When such a reinforced foam was subjected to a falling ball test using 1080 g of stainless balls, it had a height of 300 c.
No destruction was observed in the drop ball test from m. Moreover, the reinforced foam had excellent cushioning properties similar to those of conventional foams. On the other hand, the conventional foam caused a total destruction at a height of only 15 cm, and the fragments were scattered around.

Example 2 Using the same two nonwoven fabrics as in Example 1, 6 mesh in the middle, wire number 21, wire diameter 0.8 mm, eye opening 3.4 mm.
The plain weave wire mesh made of stainless steel of No. 1 was inserted, and further water jet punched to fabricate the fibers forming the nonwoven fabric and the entangled body sheet in which the fibers and the wire mesh were entangled with each other. The entangled sheet was placed between the hot polystyrene extruded foam boards immediately after being discharged by the two extruders, and pressed through a metal roll to integrate the foam and the entangled sheet.

No breakage was observed in the reinforced foam in a falling ball test from 300 cm with 1080 g of stainless balls.

[0039]

INDUSTRIAL APPLICABILITY As described above, according to the present invention, a specific entangled body sheet composed of a composite fiber and a metal mesh is adhered and integrated to the inner layer of the foam to eliminate the brittleness which is a drawback of the conventional foam. It can be significantly improved and imparted with favorable mechanical properties. In particular, impact resistance, bending resistance, and fracture resistance can be remarkably improved, and in addition, excellent cushioning properties can be provided. It is also possible to impart effective waterproofness to the foam.

[Brief description of drawings]

FIG. 1 is a schematic perspective view showing a model of one embodiment of a core / sheath type composite fiber that can be used in the present invention.

FIG. 2 is a schematic perspective view showing a model of another embodiment of the core / sheath type conjugate fiber that can be used in the present invention.

FIG. 3 is a schematic perspective view showing a model of another embodiment of the core / sheath type conjugate fiber that can be used in the present invention.

FIG. 4 is a schematic perspective view showing a model example of one embodiment of a bimetal type composite fiber that can be used in the present invention.

FIG. 5 is a schematic perspective view showing a model of one embodiment of the multi-layered conjugate fiber that can be used in the present invention.

FIG. 6 is a schematic perspective view showing a model of another embodiment of the multi-layered conjugate fiber that can be used in the present invention.

FIG. 7 is a schematic perspective view showing another model example of the multi-layered conjugate fiber that can be used in the present invention.

[Explanation of symbols]

 1: composite fiber 2, 2 ': core component 3: sheath component

Claims (8)

[Claims] 1. A reinforced foam in which a entangled sheet of fiber / metal mesh is disposed in at least an inner layer of the foam, the fiber being a composite fiber and / or a composite mainly composed of an adhesive component and a strong component. A reinforced foam, which is a thread, wherein the entangled body sheet and the foam are bonded and integrated via an adhesive component of the fiber. 2. The reinforced foam according to claim 1, wherein the foam is a polystyrene resin foam. 3. The reinforced foam according to claim 1, wherein the surface of the metal mesh is covered with a polystyrene resin. 4. The reinforced foam according to claim 3, wherein the adhesive component and the polystyrene-based resin are lower than the heat distortion temperature of the foam resin by 10 ° C. or more at the heat distortion temperature. 5. The composite fiber or composite yarn is a core / sheath composite composite fiber or composite yarn.
The reinforced foam described. 6. The reinforced foam according to claim 5, wherein the core / sheath type composite structure is a multi-core / sheath type composite fiber. 7. A entangled body sheet in which a composite fiber and / or a composite yarn mainly composed of a metal mesh and an adhesive component and a strong component are entangled is disposed in a mold having a desired shape, and a material having a latent foaming property is formed. Reinforcement characterized by filling the space in the mold and heating it to foam-form and heat-deform and / or melt the adhesive component of the fiber at the same time so that the entangled body is bonded and integrated at least in the foam inner layer portion. Method for producing foam. 8. A metal mesh and a predominantly adhesive component between a plurality of foams during or after the formation of a foam that extrudes a molten polymer / foaming agent mixture from an extruder at atmospheric pressure and causes the foaming agent to evaporate. And laminating entangled body sheets in which composite fibers and / or composite yarns composed of strong components are entangled, and thermally deforming and / or melting the adhesive component of the fibers to bond and integrate the entangled body to the inner layer of the foam. A method for producing a reinforced foam, which comprises: