JP3003278B2 - Composite foam molded article and method for producing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a composite foam molded article obtained by integrating a non-foamed layer and a foamed layer of a thermoplastic elastomer powder and a method for producing the same.

More specifically, the present invention relates to a non-foamed layer which has a complicated shape, a light weight, an excellent softness, and which can easily produce a high-grade grained or stitched pattern without residual strain. The present invention relates to a composite foam molded article made of a thermoplastic elastomer powder, in which a foamed layer having uniform cells and a smooth surface and a high expansion ratio is integrally molded by a simple molding operation, and a method for producing the same.

[0003]

2. Description of the Related Art In recent years,
As a covering material for an automobile interior material, a material which is lightweight, has excellent softness, and is provided with a luxurious leather grain pattern or stitch pattern has been required more and more.

Conventionally, a powder molding method using a vinyl chloride resin powder composition has been spotlighted as such a covering material.

The feature of this powder molding is that a mold at a temperature of 180 ° C. or more and a powder supply box are integrated and rotated, oscillated, or sprayed to weld the powder to the inner surface of the mold.
Unwelded powder is to be collected automatically or forcibly into a powder supply box (Japanese Patent Application Laid-Open No. 58-132507).

[0006] Next, the covering material produced by the powder molding method is formed by injecting and foaming a urethane raw material and bonding the same as in the case of a conventional vacuum molded product, thereby obtaining a final molded product. This urethane foam plays a role of imparting cushioning properties. However, this urethane-bonded product has unfavorable aspects such as the fact that the amine compound at the time of urethane foaming significantly promotes discoloration of the covering material of the vinyl chloride resin, and the urethane raw material is expensive.

Further, it has been attempted to produce a cushioning covering material in which a non-foamed layer made of a vinyl chloride resin and a foamed layer made of a vinyl chloride resin are simultaneously and integrally molded by a powder molding method. Although this covering material achieves the purpose of easily forming a soft grained and stitched pattern with an excellent softness, it also has the problem of recycling, waste disposal, and disposal of end-of-life vehicles. There are inconveniences such as the problem of air pollution of acidic substances caused by incineration of interior materials.

Against this background, recently, a covering material obtained by vacuum forming an olefin-based thermoplastic elastomer (hereinafter referred to as TPO) sheet has been developed. TPO vacuum molded products have a better effect than vinyl chloride resin in terms of lightness and clean materials, and achieve the purpose, but have a complex texture with high-quality leather grain or stitch pattern. It is difficult to shape a material having an irregular shape, and a large residual strain is generated during vacuum forming, and a crack may occur when used for a long period of time. Furthermore, vacuum-formed products are formed from sheets, resulting in poor product yields and high costs.

[0009]

In view of such circumstances, the present inventors have developed a method of forming a non-foamed layer and a foamed material by using a clean material that maintains high fluidity even when little pressure and shear force are applied during shaping. As a result of intensive studies on the production of a composite foam molded body with integrated layers, the powder molding method eliminates residual distortion and warpage of the molded body, forms complicated shapes such as sharp edges and overhangs, and Thus, the present inventors have found that a composite foam molded article made of a thermoplastic elastomer powder having a uniform cell and a smooth surface and a high expansion ratio can be produced, and the present invention has been completed by further various studies.

That is, the present invention relates to a composite foamed molded article in which a non-foamed layer and a foamed layer are integrated, wherein the non-foamed layer is formed from a thermoplastic elastomer powder of the following (A). Is added to 100 parts by weight of the following thermoplastic elastomer powder (A) and (B) a pyrolytic foaming agent.
2.0 to 11 parts by weight or (B) a pyrolytic foaming agent
2.0 to 11 parts by weight and (C) a liquid coating agent 0.1
An object of the present invention is to provide a composite foam molded article characterized in that it is a layer formed by blending and foaming up to 8 parts by weight . . (A) A thermoplastic elastomer powder comprising an elastomer composition of an ethylene / α-olefin copolymer rubber and a polyolefin resin, or a mixture of an ethylene / α-olefin copolymer rubber and a polyolefin resin as a crosslinking agent Is a thermoplastic elastomer powder composed of a partially crosslinked elastomer composition dynamically crosslinked in the presence of
The complex dynamic viscosity η * (1) measured in radians / second is 1.
5 × 10 ⁵ poise or less and frequency 1 radian /
The Newtonian viscosity index n calculated using the complex dynamic viscosity η * (1) in seconds and the complex dynamic viscosity η * (100) at a frequency of 100 radians / sec is 0.67 or less. Thermoplastic elastomer powder. n = {logη * (1) −logη * (100)} / 2

The present invention also relates to a method for producing a composite foamed molded article in which a non-foamed layer and a foamed layer are integrally molded by a powder molding method and heated, wherein the non-foamed layer comprises a thermoplastic elastomer of the following (A): Using a powder, 2 to 11 parts by weight of a pyrolytic foaming agent, or 2 to 11 parts by weight of a pyrolytic foaming agent and 100 parts by weight of a thermoplastic elastomer powder of the following (A) as a foaming layer, and a liquid coating agent 0 .1 to
An object of the present invention is to provide a method for producing a composite foam molded article, which comprises using a foamable thermoplastic elastomer powder composition mixed with 8 parts by weight. (A) A thermoplastic elastomer powder comprising an elastomer composition of an ethylene / α-olefin copolymer rubber and a polyolefin resin, or a mixture of an ethylene / α-olefin copolymer rubber and a polyolefin resin as a crosslinking agent Is a thermoplastic elastomer powder composed of a partially crosslinked elastomer composition dynamically crosslinked in the presence of
Complex dynamic viscosity η ^* (1) measured in radians / second is 1.
5 × 10 ⁵ poise or less and frequency 1 radian /
The Newtonian viscosity index n calculated using the complex dynamic viscosity η ^* (1) in seconds and the complex dynamic viscosity η ^* (100) at a frequency of 100 radians / sec is 0.67 or less. Thermoplastic elastomer powder. n = {logη ^* (1) −logη ^* (100)} / 2

Hereinafter, the present invention will be described in detail. The ethylene / α-olefin copolymer rubber used in the present invention is:
A rubber containing an olefin as a main component, for example, ethylene-propylene copolymer rubber, ethylene-propylene-
Non-conjugated diene copolymer rubber. Examples of non-conjugated dienes include dicyclopentadiene, ethylidene norbornene, 1,4-hexadiene, cyclooctadiene, methylene norbornene, and the like. Among them, ethylene-propylene-ethylidene norbornene rubber (hereinafter referred to as EPDM)
), An elastomer powder having excellent heat resistance, tensile properties and the like can be obtained. In particular, ASTM D-9
The Mooney viscosity (ML _{1 + 4} 100 ° C.) measured at 100 ° C. according to 27-57T is 130 to 350, preferably 200 to 300 per 100 parts by weight of an ethylene / α-olefin-based copolymer rubber. An oil-extended olefin-based copolymer rubber containing 30 to 120 parts by weight of a mineral oil-based softening agent such as a paraffin-based process oil is preferred in that the balance between tensile properties and fluidity can be achieved.

As the polyolefin resin, polypropylene or a copolymer of propylene and an α-olefin is preferably used. In particular, when propylene and an α-olefin copolymer resin are used, the hardness of the molded article can be reduced. 230 ° C according to JISK-7210,
2.Melt flow rate (MF) measured at 16 kg load
R) is preferably 20 g / 10 min or more, particularly preferably 50 g / 10 min or more. A thermoplastic elastomer powder produced using a polyolefin resin having a melt flow rate of less than 20 g / 10 minutes only softens the powder at the time of molding the powder, so that the powders hardly adhere to each other, and a molded article having high strength is obtained. I can't. The mixing ratio of the ethylene / α-olefin copolymer rubber and the olefin resin is 5% by weight or more and 80% by weight or less of the ethylene / α-olefin copolymer rubber and 20% by weight or more and 95% by weight or less of the olefin resin. It is preferred that

As a crosslinking agent for dynamically crosslinking a mixture of the ethylene / α-olefin copolymer rubber and the polyolefin resin, an organic peroxide is used. Dialkyl peroxide is preferably used as the organic peroxide. Furthermore, it is preferable to carry out dynamic crosslinking using a very small amount of an organic peroxide in the presence of a crosslinking assistant such as a bismaleimide compound. By doing so, ethylene-α-
The olefin copolymer rubber can be appropriately crosslinked to have heat resistance and at the same time to realize high fluidity. At this time, the crosslinking assistant is used in an amount of 1.5 parts by weight or less, preferably 0.6 parts by weight or less, based on 100 parts by weight of the mixture of the ethylene / α-olefin-based copolymer rubber and the polyolefin-based resin. The organic peroxide as a crosslinking agent is also used in an amount of 0.2 parts by weight or less, preferably 0.1 parts by weight or less, more preferably 0.07 parts by weight or less.

As a device used for the dynamic crosslinking, a continuous kneading extruder such as a single screw kneading extruder or a twin screw kneading extruder is preferably used. In particular, it is preferable to carry out continuous extrusion crosslinking at a shear rate of ≥10 ³ sec ^-1 using a twin-screw kneading extruder. If extrusion crosslinking is performed at a shear rate of <10 ³ sec ⁻¹ , the dispersed particle size of the ethylene / α-olefin-based copolymer rubber becomes large, making it difficult to realize low viscosity.

The partially crosslinked elastomer composition produced under these conditions has a complex dynamic viscosity η ^* (1) measured at a frequency of 1 radian / sec in a dynamic viscoelasticity measurement at 250 ° C. of 1.5 × 10 ⁵ poise. Or less, preferably 1.0 × 10 ⁵
Less than poise.

When the complex dynamic viscosity η ^* (1) measured at a frequency of 1 radian / sec exceeds 1.5 × 10 ⁵ poise, the elastomer powder produced using such an elastomer composition is melted on a mold surface. The powder slush molding method, which has a very low shear rate of 1 / sec ^-1 or less during processing, makes molding impossible.

The partially crosslinked elastomer composition produced under these conditions has a complex dynamic viscosity η measured at a frequency of 1 radian / sec in a dynamic viscoelasticity measurement at 250 ° C.
^{* Using the} (1) and the complex dynamic viscosity η ^* (100) measured at a frequency of 100 radians / second, the Newtonian viscosity index n calculated by the following equation is 0.67 or less, preferably 0.60.
It is as follows. n = {logη ^* (1) −logη ^* (100)} / 2

If the Newtonian viscosity index n exceeds 0.67, even if the complex dynamic viscosity η ^* (1) measured at a frequency of 1 radian / sec is 1.5 × 10 ⁵ poise or less, the complex dynamic The frequency dependence of the viscosity increases, and the molding pressure during molding is very small, such as 1 kg / cm ² or less, such as powder molding. Only a molded article with low physical properties can be obtained.

The elastomer used in the present invention may be an uncrosslinked ethylene-α-olefin copolymer rubber or an ethylene-α-olefin copolymer resin.
By blending 50 parts by weight or less with respect to 0 parts by weight, an elastomer having excellent flexibility can be obtained. In this case, as the α-olefin, propylene, butene, or the like is used alone or in combination. In particular, the ethylene content is 40 to 90% by weight, preferably 70 to 85% by weight.
ML 1 _{+ 4} 100 with ethylene-propylene copolymer rubber
Those having a temperature of 50 ° C. or less are preferred.

In the present invention, the pulverization of the elastomer composition is preferably performed by a freeze pulverization method using liquid nitrogen. −
The elastomer composition pellets cooled to 70 ° C. or lower, preferably −90 ° C. or lower can be obtained by a mechanical grinding method using a ball mill or the like. Pulverization at a temperature higher than -70 ° C is not preferable because the particle size of the pulverized elastomer powder becomes coarse and powder moldability decreases. In order to prevent the polymer temperature from exceeding the glass transition temperature during the pulverization operation, a method that generates less heat and has a high pulverization efficiency is preferable. Further, it is preferable that the crushing device itself is cooled by external cooling.

The obtained elastomer powder is preferably ground to such an extent that 95% or more of the total weight passes through 32 mesh of a Tyler standard sieve. If the cumulative ratio on the 32 mesh sieve exceeds 5%, this is one of the causes of thickness unevenness during pulverization molding. The thickness unevenness gives unevenness to the flexibility of the molded product, and becomes a factor that impairs the commercial value of the molded product, such as easily causing breakage wrinkles.

One of the features of the present invention is as described above.
An elastomer having a specific viscoelasticity that can be powder molded,
For example, pulverizing at a low temperature below the glass transition temperature to form a powder, making the powder a non-foamed layer, and blending a pyrolytic foaming agent with the same powder, or a pyrolytic foaming agent and a liquid coating agent As a foamed layer, there is a composite foamed molded article in which a non-foamed layer and a foamed layer are integrated.

The thermal decomposition type blowing agent used in the present invention is not particularly limited as long as it decomposes when heated and melted in powder molding to generate gas, and a general organic or inorganic chemical blowing agent can be used. it can. Specifically, azo compounds such as azodicarbonamide, 2,2′-azobisisobutyronitrile, azohexahydrobenzonitrile, diazoaminobenzene, benzenesulfonylhydrazide, benzene-
1,3-sulfonylhydrazide, diphenylsulfone-
Sulfonyl hydrazide compounds such as 3,3'-disulfonyl hydrazide, diphenyl oxide-4,4'-disulfonyl hydrazide, 4,4'-oxybis (benzenesulfonyl hydrazide), and paratoluenesulfonyl hydrazide; N, N'-dinitroso Nitroso compounds such as pentamethylenetetramine, N, N'-dinitroso-N, N'-dimethylterephthalamide, terephthalazide, p
-Azide compounds such as tertiary butyl benzazide; and inorganic compounds such as sodium bicarbonate, ammonium bicarbonate and ammonium carbonate, and at least one of them is used. Among them, azodicarbonamide and 4,4 ′
-Oxybis (benzenesulfonyl hydrazide) is preferred. The thermal decomposition type foaming agent used in the present invention has a decomposition temperature of usually 120 to 200C, preferably 120 to 180C.

Further, a foaming accelerator or a foaming aid can be used for the purpose of lowering the decomposition temperature of the thermal decomposition type foaming agent. Examples of the foaming accelerator or foaming assistant include zinc white, zinc nitrate, lead phthalate, lead carbonate, phosphate trichloride, inorganic salts such as tribasic lead sulfate, zinc fatty acid soap, lead fatty acid soap, and cadmium. Examples include metal soaps such as fatty acid soaps, borax, acids such as oxalic acid, succinic acid and adipic acid, urea, biurea, ethanolamine, glucose and glycerin.

On the other hand, a foaming inhibitor can be used for the purpose of raising the decomposition temperature of the thermal decomposition type foaming agent. As the foam inhibitor, for example, maleic acid, fumaric acid, phthalic acid, maleic anhydride, organic acids such as phthalic anhydride, stearoyl chloride, halogenated organic acids such as phthaloyl chloride,
Nitrogen compounds containing polyhydric alcohols such as hydroquinone, fatty acid amines, amides, oximes, isocyanates, etc., sulfur compounds containing mercaptans, sulfides, etc., phosphates such as phosphites, dibutyltin malate, tin chloride , Tin compounds such as tin sulfate, and hexachlorocyclopentadiene.

The pyrolytic foaming agent is used in an amount of 2.0 to 1 with respect to 100 parts by weight of the thermoplastic elastomer powder for powder molding.
1 part by weight, preferably 3 to 7 parts by weight.

In the present invention, a liquid coating agent can be used simultaneously with the above-mentioned pyrolytic foaming agent. The liquid coating agent used in the present invention is preferably a coating agent that cures at room temperature to 220 ° C. Specifically, thermosetting coating agents for protecting the surface of plastics such as polysiloxane, melamine, urethane, and fluorine-containing plastics, and polyester resins such as unsaturated polyester, alkyd, oil-free alkyd, and linear polyester resin , Melamine resin, amino resin such as modified melamine resin, novolak type,
Epoxy resins such as β-methyl epichloro type, cycloaliphatic type, acyclic aliphatic type, epoxidized fatty acid ester type, polycarboxylic acid ester type, aminoglycidyl type, chlorinated type, resorcinol type, oil modified, moisture cured block Polyurethane resin such as one-pack type polyurethane resin, two-pack type of catalyst-cured polyol-cured polyurethane resin, organic solvent type,
Aqueous type, non-solvent type acrylic resin and methacrylic acid ester-based acrylic resin are exemplified. Among these liquid coating agents, polysiloxane, acyclic aliphatic type and cycloaliphatic type epoxy resin,
Solvent-free acrylic resins such as acrylic syrup are preferred, and among them, epoxy resins that cure at room temperature to 150 ° C. are particularly preferred.

The liquid coating agent is usually 50
Although those having a viscosity of about 50,000 cps can be used, they can be diluted with a solvent at the time of use. In the present invention, an ordinary curing agent can be used in combination for the purpose of accelerating the curing of the liquid coating agent. Examples of the curing agent for the epoxy resin include amines such as diethylenetriamine, triethylenetetramine, tetraethylenepentamine, 2,4,6-tris (dimethylaminomethyl) phenol, and meta-xylylenediamine; phthalic anhydride; Examples thereof include acid anhydrides such as hydrophthalic acid, methylnadic anhydride, and pyromellitic anhydride, polyamide resins, and mixtures thereof. Examples of the curing agent for the acrylic resin include organic compounds such as dicumyl peroxide, di-tert-butyl peroxide, 2,5-dimethyl-2,5-di (tert-butylperoxy) hexane, benzoyl peroxide, and laurocloperoxy. At least one peroxide can be used.

The liquid coating agent is used in an amount of 0.1 part by weight per 100 parts by weight of the thermoplastic elastomer powder for powder molding.
To 8 parts by weight, preferably 0.2 to 5 parts by weight.
The curing agent used in combination with the liquid coating agent is usually blended in an amount of 100 parts by weight or less based on 100 parts by weight of the liquid coating agent.

The production method of the present invention is an improved powder molding method, that is, a fluid immersion method, an electrostatic coating method, a powder spraying method, a powder rotational molding method, and a powder slush molding method. An improved method is preferred, and the powder slush molding method refers to the molding method described in JP-A-58-132507.

That is, the production method of the present invention
(1) A container having an opening containing a required amount of a specific thermoplastic elastomer powder is fixed to a mold having an opening heated to a temperature sufficiently higher than the melting temperature of the powder by fixing the opening to the container. It is fixed to the hollow part inside the mold and integrated,
A step of rapidly supplying powder from the container to each part in the mold with rotation and / or rocking, adhering and melting, and discharging excess powder into the container; and (2) a thermoplastic elastomer similar to the above. 2 to 11 parts by weight of a pyrolytic foaming agent, or 2 to 11 parts by weight of a pyrolytic foaming agent and 0.1 to 100 parts by weight of a powder, based on 100 parts by weight of a powder.
A container having an opening in which a required amount of the foamable thermoplastic elastomer powder composition containing 8 parts by weight was added was obtained in the step (1) in which the container was heated to a temperature sufficiently higher than the melting temperature of the powder composition. The mold having a non-foamed layer and the opening are fixed together, or fixed to the hollow part in the mold and integrated, and the foamable thermoplastic elastomer powder composition is non-foamed from the container with rotation and / or rocking. A step of rapidly supplying, adhering and melting to each part in the layer, discharging an excess powder composition into a container, and (3) a step of heating and foaming the molded article obtained in the step. It is possible to provide a method for producing a composite foam molded article characterized by the following.

Therefore, the thermoplastic elastomer powder and the expandable thermoplastic elastomer powder composition used in such a powder molding method are excellent in powder flowability and are mainly supplied from a mold under a low shear rate and a low pressure. It must be easily melted by heat.

The mold heating system used in the powder molding method according to the present invention is not particularly limited. For example, a gas heating furnace system, a heating medium oil circulation system, a heating medium oil or hot fluid sand can be used. Immersion method or high-frequency induction heating method and the like, when foaming the molten powder composition,
These heating sources can be used.

The molding temperature of the non-foamed layer of the present invention is usually 16
It is 0-300 degreeC, Preferably it is 180-280 degreeC. The molding time is not particularly limited, and is appropriately selected depending on the size of the molded body, the thickness of the molded body, and the like. The temperature at which the foamed layer of the present invention is foamed is usually from 180 to 2
80 ° C., preferably 180 to 260 ° C. The foaming time is not particularly limited, and is appropriately selected depending on the thickness of the foamed layer and the foaming ratio.

The method for blending the pyrolytic foaming agent, or the pyrolytic foaming agent and the liquid coating agent into the powdery thermoplastic elastomer powder is not particularly limited. It is preferable to previously mix a pyrolytic foaming agent with the powder, and then mix a liquid coating agent with these compositions.

When the molded article formed by powder molding with the expandable thermoplastic elastomer powder composition used in the present invention is released from the mold, the inner surface of the mold is strongly adhered. Trouble may occur. Therefore, it may be necessary to coat the inner surface of the mold before molding by spraying a generally used release agent, for example, dimethylpolysiloxane. However, in order to continuously produce many pieces, it is necessary to coat a release agent every time several pieces are molded, which leads to an increase in molding cost.
In such a case, a method of improving the mold material may be considered. However, a methylpolysiloxane compound as an internally added mold release agent is added to the elastomer powder composition in an amount of 2 parts by weight or less per 100 parts by weight of the elastomer powder composition. Is effective. In this case, the timing of addition may be before or after powdering. In this case, the methylpolysiloxane compound may have a viscosity at 25 ° C. of 20 centistokes or more. The preferred viscosity range is 50-5
000 centistokes. If the viscosity is too high, the effect as a release agent is reduced. On the other hand, when the amount of the internally added release agent is more than 2 parts by weight, heat fusion between the elastomer powders is hindered, and only a molded article having poor mechanical properties can be obtained. In addition, the internally added mold release agent bleeds on the mold surface, and the mold is undesirably contaminated.

In the present invention, known heat stabilizers such as phenol-based, sulfite-based, phenylalkane-based, phosphite-based, amine-based or amide-based stabilizers,
Antioxidants, weathering stabilizers, antistatic agents, lubricants such as metallic soaps and waxes, coloring pigments and the like can be added in necessary amounts.

[0039]

As described above in detail, according to the present invention, a non-foamed layer capable of forming a molded article having a small residual strain and a complicated shape by a powder molding method, Thus, it is possible to easily produce a composite foam molded article made of a thermoplastic elastomer powder in which a foam layer having a uniform cell and a smooth surface and a high foam ratio is integrated.

Further, the present invention can provide a composite foam molded article excellent in light weight and cleanness. The composite foam molded article of the present invention is, for example, in the automotive field, instrument panel, console box, armrest, headrest, door trim, rear panel, pillar trim, sun visor, trunk room trim, trunk lid trim,
Airbag storage boxes, seat buckles, headliners, glove boxes, steering wheel covers, interior skin materials such as ceiling materials, kick plates, change lever boots, interior moldings such as ceiling materials, spoilers, side moldings, license plate housings, Suitable for car exterior parts such as mirror housing, air dam skirt, mudguard, etc.

Further, the composite foam molded article of the present invention is used in the fields of home electric appliances and office automation equipment, for example, for televisions, videos,
Washing machine, dryer, vacuum cleaner, cooler, air conditioner, remote control case, microwave oven, toaster, coffee maker, pot, jar, dishwasher, electric razor, hair dryer, microphone, headphones, beauty equipment, CD / cassette box Suitable for skin materials and housings of personal computers, typewriters, projectors, telephones, copiers, facsimile machines, telexes, etc.

In the field of sports goods, the composite foam molded article of the present invention can be used, for example, for decorative parts for sports shoes,
Rackets for various ball games, grips for sports equipment and supplies,
Suitable for the saddle skin and handle grip of bicycles, motorcycles, and tricycles.

The composite foam molded article of the present invention can be used in the field of construction and housing, for example, for skin materials such as furniture, desks and chairs, gates,
Doors, fences and other skin materials, wall decoration materials, ceiling decoration materials, curtain wall skin materials, indoor flooring materials such as kitchens, washrooms, toilets, etc., outdoor flooring materials such as verandas, terraces, balconies and carports, and entrances Mats, tablecloths, coasters,
Suitable for rugs such as ashtrays.

In the field of industrial products, the composite foam molded article of the present invention is suitable, for example, for grips of electric tools, hoses, skin materials thereof, and packing materials.

In addition to the above, the composite foam molded article of the present invention can be used for molding bags, cases, files, notebooks, albums, stationery, camera bodies, skin materials such as dolls and other toys, and watch bands and the like. Suitable for body, forehead frame and skin material.

[0046]

Next, the present invention will be described in more detail with reference to examples, but the present invention is not limited to these examples.

The appearance of the composite foam molded article, the thickness of the composite foam molded article, the state of the foam layer cell, and the expansion ratio of the foam layer in the examples and comparative examples were evaluated as follows. The appearance foam layer of the composite foam molded article was visually observed and evaluated as follows. ：: There is no unevenness in the thickness and the foam is uniformly formed. Δ: Thickness unevenness, but almost uniform foaming. X: Thickness unevenness is large and foaming is uneven. XX: Almost no foaming. The thickness of the non-foamed layer and the foamed layer of the composite foamed molded article were measured with a dial gauge manufactured by Toyo Seiki. The state of the foam layer cell The cross section of the foam was visually observed and evaluated as follows. ：: The cells are uniform. Δ: Cells are slightly uneven. ×: The cells are non-uniform. Expansion ratio of foam layer The expansion ratio was calculated by the following equation. Expansion ratio = density of non-foamed layer / density of foamed layer The density of the foamed layer is a density meter (Dens manufactured by Toyo Seiki Seisaku-sho, Ltd.)
It was measured in water using an imeter-H).

The decomposition temperature of the pyrolytic foaming agent was measured as follows. The sample was placed in a capillary tube, heated at a rate of 2 ° C./min with a melting point measuring apparatus (MP type, Yanagimoto Seisakusho), and the temperature at which the sample started foaming was measured as a decomposition temperature.

Example 1 Mineral oil-based softener (Diana Process PW # 380, manufactured by Idemitsu Kosan Co., Ltd.) per 100 parts by weight of EPDM (ML _{1 + 4} 100 ° C. = 242, propylene content = 28% by weight, iodine value = 12) ) Oil-extended EPDM with 100 parts by weight
(ML _{1 + 4} 100 ° C. = 53) 40 parts by weight, 60 parts by weight of a propylene / ethylene random copolymer resin (ethylene content = 5% by weight, MFR = 85 g / 10 minutes) and a crosslinking assistant (manufactured by Sumitomo Chemical; After kneading 0.4 part by weight of a registered trademark Sumifine BM (bismaleimide compound) using a Banbury mixer for 10 minutes, a pellet-like masterbatch for crosslinking (hereinafter referred to as MB) using an extruder. did.

This M. B. 100 parts by weight of an organic peroxide (manufactured by Sanken Kako, registered trademark Samperox APO,
0.04 parts by weight of 2,5-dimethyl-2,5-di (t-butylperoxynohexane) was added, and the mixture was heated to 220 ° C. using a twin-screw kneader (registered trademark TEX # 44, manufactured by Nippon Steel Works).
Was performed to obtain elastomer composition pellets. After cooling the pellets to a temperature of −100 ° C. using liquid nitrogen, the pellets are frozen and pulverized to have a complex dynamic viscosity η ^* (1) of 3.1 × 10 ³ poise and a Newton viscosity index n of 0.2.
Thus, No. 4 thermoplastic elastomer powder for powder molding was obtained. This powder passed 99% by weight through a 32 mesh Tyler standard sieve.

A metal mold (30 cm × 30 cm) made of nickel and a flat plate was heated in a gear oven at 300 ° C. When the surface temperature of the mold reached 220 ° C., the thermoplastic elastomer powder for powder molding was sprinkled for 5 seconds. Immediately after the excess powder is discharged, 100 parts by weight of the same thermoplastic elastomer powder for powder molding as described above is applied to a pyrolytic blowing agent azo compound (Cermic CAP, manufactured by Sankyo Chemical Co., Ltd.).
-500, main component: azodicarbonamide, decomposition temperature 1
(50 ° C.) A foamable thermoplastic elastomer powder composition prepared by blending 5 parts by weight was sprinkled for 20 seconds to discharge an excessive powder composition. Further, the mold is heated to an ambient temperature of 2
The composition was placed in a gear oven at 20 ° C. and heated for 60 seconds to foam the composition. Next, the mold was taken out of the gear oven, cooled with water, and the composite foam molded article was released from the mold. Table 1 shows the evaluation results of the composite foam molded article.

Example 2 The propylene / ethylene random copolymer resin 60 was used in place of 40 parts by weight of the oil-extended EPDM in Example 1 and 50 parts by weight.
Except that the weight part is changed to 50 parts by weight, the complex dynamic viscosity η ^* (1) is 1.5 × 10 ⁴ poise under the same conditions as in Example 1.
A thermoplastic elastomer powder for powder molding having a Newtonian viscosity index n of 0.47 was obtained. This powder passed 99% by weight through a 32 mesh Tyler standard sieve. 5 parts by weight of the same pyrolytic foaming agent as in Example 1 was added to 100 parts by weight of the same powder as this powder to obtain a foamable thermoplastic elastomer powder composition. Less than,
A composite foam molded article was manufactured under the same conditions as in Example 1. Table 1 shows the evaluation results of the composite foam molded article.

Example 3 Except that 60 parts by weight of a propylene-butene random copolymer resin (butene content = 24% by weight, MFR = 90 g / 10 minutes) was used, and that 40 parts by weight of oil-extended EPDM in Example 1 was used. Complex dynamic viscosity η ^{* under the} same conditions as in Example 1 ^.
(1) is 6.9 × 10 ³ poise, Newton viscosity index n
Was 0.39 to obtain a thermoplastic elastomer powder for powder molding. This powder passed 99% by weight through a 32 mesh Tyler standard sieve. 5 parts by weight of the same pyrolytic foaming agent as in Example 1 was added to 100 parts by weight of the same powder as this powder to obtain a foamable thermoplastic elastomer powder composition. Hereinafter, a composite foam molded article was manufactured under the same conditions as in Example 1. Table 1 shows the evaluation results of the composite foam molded article.

Example 4 A complex was obtained under the same conditions as in Example 3 except that 40 parts by weight of the oil-extended EPDM in Example 3 was changed to 50 parts by weight and 60 parts by weight of the propylene-butene random copolymer resin was changed to 50 parts by weight. Dynamic viscosity η ^* (1) is 1.8 × 10 ⁴ poise,
A thermoplastic elastomer powder for powder molding having a Newtonian viscosity index n of 0.52 was obtained. This powder passed 98% by weight of a 32 mesh Tyler standard sieve. 5 parts by weight of the same pyrolytic foaming agent as in Example 1 was added to 100 parts by weight of the same powder as this powder to obtain a foamable thermoplastic elastomer powder composition. Less than,
A composite foam molded article was manufactured under the same conditions as in Example 1. Table 1 shows the evaluation results of the composite foam molded article.

Example 5 50 parts by weight of a propylene-ethylene random copolymer resin (ethylene content = 3% by weight, MFR = 60 g / 10 minutes) was used, and 40 parts by weight of the oil-extended EPDM in Example 1 was 50 parts by weight. A thermoplastic elastomer powder for powder molding having a complex dynamic viscosity η ^* (1) of 3.4 × 10 ⁴ poise and a Newtonian viscosity index n of 0.59 was obtained under the same conditions as in Example 1 except that Was. This powder passed 99% by weight through a 32 mesh Tyler standard sieve. Example 1 was added to 100 parts by weight of a powder similar to this powder.
5 parts by weight of the same thermally decomposable foaming agent as in Example 1 was blended to obtain a foamable thermoplastic elastomer powder composition. Hereinafter, a composite foam molded article was manufactured under the same conditions as in Example 1. Table 1 shows the evaluation results of the composite foam molded article.

Example 6 The same powder as in Example 1 was used as a thermoplastic elastomer powder for powder molding. Further, a thermal decomposition type blowing agent sulfonyl hydrazide compound (manufactured by Sankyo Chemical Co., Ltd., CellMike S, 4,4'-oxybis (benzenesulfonyl hydrazide), decomposition temperature 155 ° C., relative to 100 parts by weight of the same powder as this powder. 5) parts by weight to obtain a foamable thermoplastic elastomer powder composition. Hereinafter, a composite foam molded article was manufactured under the same conditions as in Example 1. Table 1 shows the evaluation results of the composite foam molded article.

Example 7 The same powder as in Example 3 was used as the thermoplastic elastomer powder for powder molding. Also, 100 parts by weight of the same powder as this powder was added to the pyrolytic foaming agent 5.
A liquid coating agent (manufactured by Sumitomo Chemical Co., Ltd., Sumiuni, registered trademark) diluted with 20 ml of ethyl acetate was added to the foamable thermoplastic elastomer powder composition for powder molding obtained in Example 3, which was mixed with parts by weight. A main component: polysiloxane) was added in an amount of 0.5 part by weight to obtain a foamable thermoplastic elastomer powder composition. Hereinafter, a composite foam molded article was manufactured under the same conditions as in Example 3. Table 1 shows the evaluation results of the composite foam molded article.

Example 8 The same powder as in Example 3 was used as a thermoplastic elastomer powder for powder molding. Also, 100 parts by weight of the same powder as this powder was added to the pyrolytic foaming agent 5.
The foamable thermoplastic elastomer powder composition for powder molding obtained in Example 3 was mixed with a liquid coating agent (Sumitomo Chemical Industry Co., Ltd., registered trademark SUMIPEX CEMENT 7, main component: acrylic resin) ) 0.5 part by weight and one drop of a curing agent containing benzoyl peroxide as a main component were blended to obtain a foamable thermoplastic elastomer powder composition. Hereinafter, a composite foam molded article was manufactured under the same conditions as in Example 3. Table 1 shows the evaluation results of the composite foam molded article.

Example 9 The same powder as in Example 5 was used as the thermoplastic elastomer powder for powder molding. Further, for 100 parts by weight of the same powder as this powder, 5 parts by weight of the same pyrolytic foaming agent as in Example 1 and a liquid coating agent (Wako Pure Chemical Industries, Quetal, ethylene glycol diglycidyl ether) 0 .25 parts by weight, 0.23 parts by weight of methylnadic anhydride and 0.02 part by weight of 2,4,6-tris (dimethylaminomethyl) phenol were mixed to obtain a foamable thermoplastic elastomer powder composition. Hereinafter, a composite foam molded article was manufactured under the same conditions as in Example 1. Table 1 shows the evaluation results of the composite foam molded article.

Comparative Example 1 A composite foam molded article was produced in the same manner as in Example 1, except that the blending amount of the pyrolytic foaming agent in Example 1 was changed to 1.5 parts by weight. Table 1 shows the evaluation results of the composite foam molded article.

Example 10 The blending amount of the pyrolytic blowing agent in Example 1 was changed to 3 parts by weight.
A composite foam molded article was produced in the same manner as in Example 1 except that the amount was changed to parts by weight. Table 1 shows the evaluation results of the composite foam molded article.

Example 11 The blending amount of the pyrolytic foaming agent in Example 1 was changed to 8 parts by weight to 8 parts by weight.
A composite foam molded article was produced in the same manner as in Example 1 except that the amount was changed to parts by weight. Table 1 shows the evaluation results of the composite foam molded article.

Example 12 The blending amount of the pyrolytic foaming agent of Example 1 was changed to 1 part by weight.
A composite foam molded article was produced in the same manner as in Example 1 except that the amount was 0 part by weight. Table 1 shows the evaluation results of the composite foam molded article.

Comparative Example 2 The blending amount of the pyrolytic foaming agent in Example 1 was 5 parts by weight
Except for using 2 parts by weight, a composite foam molded article was produced in the same manner as in Example 1. Table 1 shows the evaluation results of the composite foam molded article.

Example 13 The same powder as in Example 3 was used as the thermoplastic elastomer powder for powder molding. Also, 100 parts by weight of the same powder as this powder was added to the pyrolytic foaming agent 5.
The foaming thermoplastic elastomer powder composition for powder molding obtained in Example 3 was mixed with a liquid coating agent (manufactured by Sumitomo Chemical Co., Ltd., Sumiepoxy ELA115 registered trademark, epichlorohydrin and bisphenol A). Cycloaliphatic epoxy resin)
5 parts by weight and 0.05 parts by weight of a curing agent triethylenetetramine were blended to obtain a foamable thermoplastic elastomer powder composition. Hereinafter, a composite foam molded article was manufactured under the same conditions as in Example 3. Table 1 shows the evaluation results of the composite foam molded article.

Example 14 The blending amount of the liquid coating agent in Example 13 was 0.5.
1 part by weight and 0.05 part by weight of a curing agent are 0.1 part by weight.
A composite foam molded article was manufactured in the same manner as in Example 13 except that the amount was changed to parts by weight. Table 1 shows the evaluation results of the composite foam molded article.

Example 15 The blending amount of the liquid coating agent in Example 13 was 0.5.
3 parts by weight, and 0.05 part by weight of a curing agent to 0.3 part by weight.
A composite foam molded article was manufactured in the same manner as in Example 13 except that the amount was changed to parts by weight. Table 1 shows the evaluation results of the composite foam molded article.

Comparative Example 3 The blending amount of the liquid coating agent in Example 13 was 0.5
A composite foam molded article was produced in the same manner as in Example 13 except that the weight part was changed to 10 parts by weight. Table 1 shows the evaluation results of the composite foam molded article.

[0069]

Example 16 A white pigment (manufactured by Sumika Color Co., Ltd., White PV-74) was added to the same powder as the thermoplastic elastomer powder obtained in Example 3.
2) 1.0 part by weight of a colored thermoplastic elastomer powder (5000 g of resin powder) is supplied to a super mixer having a capacity of 20 liters and mixed at 500 rpm for 10 minutes to obtain a thermoplastic elastomer powder composition for powder molding (non-dispersed). 5050 g of a white product (for a foam layer) was obtained.

A powder composition (0.7 parts by weight of White PV-742, manufactured by Sumika Color Co., Ltd., Bl) was added to the same powder composition as the foamable thermoplastic elastomer powder composition obtained in Example 3.
1.0 part by weight of ackPV-817 was mixed) to obtain 5300 g of a foamable thermoplastic elastomer powder composition colored in gray.

Two rectangular containers (powder supply boxes) made of stainless steel as shown in FIGS. 1 to 3 are prepared, and one contains a thermoplastic elastomer powder composition for a non-foamed layer, and the other contains
4000 g of the foamable thermoplastic elastomer powder composition was supplied to the table. This square container is 600mm x 2
It has a rectangular opening 1 of 20 mm, a depth of 210 mm, and is attached to the uniaxial rotating device 3.

On the other hand, the nickel electroforming mold shown in FIGS. 4 to 6 having the opening 1 of the powder supply box shown in FIG. 1 and the opening 4 having the same size was preheated in a gas furnace at 300 ° C. . This mold has a thickness of 3 mm, and has a complicated shape in which an inner surface is provided with a wrinkle pattern 5 and a grain pattern 6. When the surface temperature of the mold reaches 250 ° C., the heated mold is immediately placed in the opening 4 (600 mm × 220 m).
m) is directed downward, and is placed in the opening 1 of the powder supply box filled with the thermoplastic elastomer powder composition for the non-foaming layer, and the outer frame attached around both openings is placed. They were brought into close contact, fixed with clips 2 and integrated.

When the surface temperature of the mold reached 220 ° C., the powder supply box filled with the thermoplastic elastomer powder composition for the non-foamed layer was immediately rotated by 180 °, and the powder was brought into contact with the mold for 3 seconds. Fused. Immediately, the powder supply box was rotated back by 180 °, and excess powder attached to the complicated shape portion was blown off to the powder supply box.

Immediately, the opening 4 of the mold on which the non-foamed layer is formed faces downward, and the opening 4 of the mold is
The powder supply box containing the foamable thermoplastic elastomer powder composition was placed in the opening 1 of the powder supply box, and the outer frames attached around both the openings were brought into close contact with each other, fixed with the clip 2 and integrated. The surface temperature of the mold at this time was 189 ° C.

Immediately, the powder supply box containing the expandable thermoplastic elastomer powder composition was rotated by 180 °, and the powder composition was brought into contact with the mold for 15 seconds to be fused. Next, the powder supply box was rotated back by 180 °, and the excess powder composition adhering to the complicated shape portion was blown off to the powder supply box. The mold was removed from the powder supply box with the mold opening 4 facing downward.
Subsequently, after the mold was post-heated in a heating furnace at 200 ° C. for 1 minute, it was immediately cooled with water and the molded article was released.

The obtained composite foamed molded article had a non-foamed layer of 1
The thickness was 20 g, the thickness was 0.7 mm, the foam layer was 110 g, the thickness was 3.3 mm, and the expansion ratio was 4.0. The non-foamed layer had no underfill or pinholes, and had a faithfully reproduced line pattern and grain pattern. The foam layer had uniform foam cells.

[Brief description of the drawings]

FIG. 1 is a plan view of a powder supply box.

FIG. 2 is an elevation view of a powder supply box.

FIG. 3 is a side view of the powder supply box.

FIG. 4 is a plan view of a mold.

FIG. 5 is an elevation view of a mold.

FIG. 6 is a side view of a mold.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Opening 2 ... Clip 3 ... Uniaxial rotation device (handle) 4 ... Opening 5 ... Latch pattern part in a mold 6 ... Mold inner grain pattern part

Continued on the front page (72) Inventor Tadashi Hikasa 5-1, Anesaki Beach, Ichihara-shi, Chiba Sumitomo Chemical Industries Co., Ltd. (72) Inventor Hiroaki Tsumori 5-1, Anesaki Beach, Ichihara-shi, Chiba Prefecture, Sumitomo Chemical (58) ) Field surveyed (Int. Cl. ⁷ , DB name) B32B 1/00-35/00 C08J 9/00-9/42

Claims (6)

(57) [Claims] 1. A composite material comprising a non-foamed layer and a foamed layer integrated with each other.
In the foam molded article, the non-foamed layer has a thermoplastic resin of the following (A).
It is a layer formed from lastmer powder,
The layer is a thermoplastic elastomer powder of the following (A)100
Parts by weightAnd (B) a pyrolytic foaming agent2.0-11 parts by weight
Or (B) a pyrolytic foaming agent2.0-11 parts by weightWhen
(C) Liquid coating agent0.1 to 8 parts by weightIs compounded
Foam molding characterized by being a layer formed by foaming
body. (A) Ethylene / α-olefin copolymer rubber and poly
Thermoplastic made of elastomer composition with olefin resin
Plastic elastomer powder or ethylene α-ole
Mixing of fin copolymer rubber and polyolefin resin
-Crosslinking type gel obtained by dynamically cross-linking the product in the presence of a crosslinker
Thermoplastic elastomer powder comprising a stoma composition
At a frequency of 1 in the dynamic viscoelasticity measurement at 250 ° C.
The complex dynamic viscosity η * (1) measured in radians / second is 1.
5 × 10^FiveLess than poise and frequency 1 radian /
Complex dynamic viscosity η * (1) in seconds and frequency 100 radians
/ Complex dynamic viscosity η * (100)
The calculated Newton's viscosity index n is 0.67 or less
Thermoplastic elastomer powder. n = {logη * (1) −logη * (100)} / 2 2. The composite foam molded article according to claim 1, wherein (B) the pyrolytic foaming agent is an azo compound or a sulfonyl hydrazide compound. 3. The composite foam molded article according to claim 1, wherein (C) the liquid coating agent is a coating agent selected from polysiloxane, epoxy resin and acrylic resin. 4. A method for producing a composite foamed molded article in which a non-foamed layer and a foamed layer are integrally molded by a powder molding method and heated, wherein a thermoplastic elastomer powder of the following (A) is used as the non-foamed layer, As a foamed layer, 2 to 11 parts by weight of a pyrolytic foaming agent or 2 to 11 parts by weight of a pyrolytic foaming agent with respect to 100 parts by weight of a thermoplastic elastomer powder of the following (A).
A method for producing a composite foam molded article, comprising using a foamable thermoplastic elastomer powder composition, which is prepared by mixing 0.1 parts by weight of a liquid coating agent with 0.1 parts by weight of a liquid coating agent. (A) A thermoplastic elastomer powder comprising an elastomer composition of an ethylene / α-olefin copolymer rubber and a polyolefin resin, or a mixture of an ethylene / α-olefin copolymer rubber and a polyolefin resin as a crosslinking agent Is a thermoplastic elastomer powder composed of a partially crosslinked elastomer composition dynamically crosslinked in the presence of
Complex dynamic viscosity η ^* (1) measured in radians / second is 1.
5 × 10 ⁵ poise or less and frequency 1 radian /
The Newtonian viscosity index n calculated using the complex dynamic viscosity η ^* (1) in seconds and the complex dynamic viscosity η ^* (100) at a frequency of 100 radians / sec is 0.67 or less. Thermoplastic elastomer powder. n = {logη ^* (1) −logη ^* (100)} / 2 5. The method according to claim 4, wherein (B) the pyrolytic foaming agent is an azo compound or a sulfonyl hydrazide compound. 6. The method according to claim 4, wherein (C) the liquid coating agent is a coating agent selected from polysiloxane, epoxy resin and acrylic resin.