JP6962716B2 - Fiber complex - Google Patents

Description

The present invention relates to fiber complexes. More specifically, it relates to a fiber complex having excellent strength in a high temperature environment.

Since fiber-reinforced synthetic resin reinforced with fibers is lightweight and has high mechanical strength, in recent years, light weight and high mechanical strength in the fields of automobiles, ships, aviation, medical treatment, etc. have been required. Its use is expanding in the fields where it is used.

As a composite having a fiber-reinforced synthetic resin, a fiber composite in which a foam is used as a core material and a fiber-reinforced synthetic resin is laminated and integrated on the surface of the core material is proposed for the purpose of weight reduction and improvement of heat insulation. (See Patent Documents 1 and 2).

Further, it has been proposed to use a highly heat-resistant resin such as a polyamide resin or a polyethylene terephthalate resin for the foam of the core material (see Patent Documents 3 and 4).

Japanese Unexamined Patent Publication No. 2015-83365 Japanese Unexamined Patent Publication No. 2005-313613 Japanese Unexamined Patent Publication No. 2014-208417 Japanese Unexamined Patent Publication No. 2013-188953

In recent years, there has been an increasing demand for fiber complexes that can withstand use in a higher temperature environment and for shortening the molding cycle thereof.

However, although the fiber composite of Patent Document 1 is composed of a core material having a bubble structure and a surface material made of a thermoplastic resin and carbon fibers, it is not possible to obtain a fiber composite having good rigidity in a high temperature environment such as 100 ° C. difficult.

The composite of Patent Document 2 defines the strength of the reinforcing fibers in the skin material, and although the strength is high in a room temperature environment, it is possible to obtain a fiber composite having good rigidity in a high temperature environment such as 100 ° C. difficult.

The fiber composite of Patent Document 3 uses a polyamide foam sheet having high heat resistance for the foamed resin, and a polyethylene terephthalate foam having high heat resistance for the fiber composite of Patent Document 4, but in an environment of 100 ° C. , Bending strength is still insufficient.

Therefore, an object of the present invention is to provide a fiber composite capable of obtaining rigidity and an aesthetic appearance in a high temperature (for example, 100 ° C.) environment.

In order to solve the above problems, the present inventors are a fiber composite in which a skin material containing fibers and a resin is laminated on at least a part of the surface of the core material, and the above-mentioned cross section of the fiber composite in the thickness direction. By including a resin portion having a specific width or more and bubbles having an average cell ratio in a specific range in the core material, excellent rigidity and an aesthetic appearance can be obtained in a high temperature (for example, 100 ° C.) environment. This has led to the present invention.

That is, the present invention is as follows.
(1)
A fiber complex containing a core material containing a foamed resin and having a skin material containing fibers and a resin laminated on at least a part of the surface of the core material.
Wherein in the thickness direction of the cross section of the fiber composite, the width 8μm or more resin portion in the core material (A), and average major axis is viewed contains air bubbles (C) of 5～800Myuemu,
In the cross section, at least a part of the resin portion (A) is continuously connected from one surface of the core material to the other surface.
In the cross section, the structure in which the plurality of bubbles (C) are surrounded by the resin portion (A) is included.
A fiber composite characterized in that the foamed resin is a polyamide-based resin.
(2)
The fiber composite according to (1), wherein the resin portion (A) has a continuous point where the width of the resin portion is 8 μm or more and continues for 1 mm or more.
(3)
The fiber composite according to (1) or (2), wherein the resin portion (A) has an average width of 8 to 40 μm.

According to the present invention, it is possible to provide a fiber composite capable of obtaining rigidity and an aesthetic appearance in a high temperature (for example, 100 ° C.) environment.

FIG. 1 is a schematic view showing a cross-sectional view of an example of the fiber composite of the present embodiment.

Hereinafter, a mode for carrying out the present invention (hereinafter, also referred to as “the present embodiment”) will be described in detail. The following embodiments are examples for explaining the present invention, and the present invention is not limited to the following embodiments, and can be variously modified and implemented within the scope of the gist thereof.

[Fiber complex]
The fiber composite of the present embodiment is a fiber composite containing a core material containing a foamed resin, and a skin material containing a fiber and a resin is laminated on at least a part of the surface of the core material. In the cross section in the thickness direction of the above, the core material contains a resin portion (A) having a width of 8 μm or more and bubbles (C) having an average major axis of 5 to 800 μm.

The fiber composite of the present embodiment is preferably a composite in which a skin material containing fibers and a resin is arranged on at least a part of at least one surface of a core material containing a foamed resin. The skin material may be provided on both surfaces of the core material, or may be provided on one side. The skin material may be provided on a part of the surface of the core material, or may be provided on the entire surface.

That is, in the fiber composite of the embodiment, the portion of the surface of the core material on which the skin material is arranged may be appropriately determined according to the shape of the core material, for example, in the case of a sheet (see Examples described later). May be all or part of one side or both sides, in the case of a lump, it may be all or part of the surface that can be seen from a specific direction in a stationary state, and in the case of a linear shape, the extending direction from one end. May be all or part of the surface for a given length.

A cross section of the fiber composite of the present embodiment will be described with reference to FIG.
FIG. 1 is a cross section of the fiber composite of the present embodiment in the thickness direction. The fiber composite 1 is a fiber composite 1 in which the skin material 3 is laminated on the entire surfaces of both sides of the core material 2. The core material 2 includes a substantially solid resin portion (A) 4 having a width of 8 μm or more and bubbles (C) 6 having an average major axis of 5 to 800 μm. By having the wide resin portion (A), it is excellent in rigidity, appearance, and surface cosmeticity in a high temperature environment.
In the example of FIG. 1, the bubble (C) 6 is surrounded by a thin resin portion (B) and / or a thick resin portion (A). That is, the boundary between adjacent bubbles is composed of a resin portion (A) and / or a resin portion (B). In particular, since a plurality of bubbles surrounded by the resin portion (B) are contained in the region surrounded by the resin portion (A), the rigidity at high temperature is further excellent.
Further, the resin portion (A) 4 is continuous in the thickness direction from one surface (for example, the upper surface of FIG. 1) of the core material on which the skin material 3 is laminated to the other surface (lower surface of FIG. 1). Are connected. The connection may be straight or may be connected in a mesh pattern as shown in FIG. Further, most of the resin portion (A) 4 is closed, and the closed resin portion (A) 4 contains the resin portion (B) 5 and the bubbles 6.

(Core material)
The core material in the fiber composite of the present embodiment contains a foamed resin. The core material may contain a member other than the foamed resin, depending on the purpose and application. However, from the viewpoint that the characteristics of the foamed resin can be easily obtained, it is preferable that the resin contained in the core material is only the foamed resin, and it is more preferable that the core material is composed of only the foamed resin. Further, the core material is preferably a foam containing a foamed resin, and more preferably a foam made of only a foamed resin.

-Foam resin-
The foamed resin is preferably a resin having high heat resistance, more preferably a foamed resin containing a polyester resin, a polyamide resin, a polyphenylene ether resin, a (meth) acrylic resin or the like as a main component, and particularly preferably a polyamide. It is a based resin and a polyphenylene ether based resin.
The foamed resin may be used alone or in combination of two or more.
Here, the term "main component" means that the total amount of the foamed resin (100% by mass) is 50% by mass or more, 60% by mass or more, or 100% by mass.

A skin material, which will be described later, can be superposed on the core material to raise the temperature and pressure to form a laminated fiber composite. Therefore, the higher the elastic modulus of the core material, the better the appearance of the fiber composite such as the thickness when it is made into a fiber composite. From this point of view, a polyamide resin or a polyphenylene ether resin is used as the foamed resin. Suitable.

As the polyester-based resin, a high molecular weight linear polyester obtained as a result of a condensation reaction of a dicarboxylic acid and a dihydric alcohol is preferable. Of these, aromatic polyester resins are preferable.
The polyester resin may be used alone or in combination of two or more.

The aromatic polyester resin is preferably a polyester containing an aromatic dicarboxylic acid component and a diol component, and examples thereof include polyethylene terephthalate, polypropylene terephthalate, polybutylene terephthalate, polycyclohexanedimethylene terephthalate, polyethylene naphthalate, and polybutylene naphthalate. Among them, polyethylene terephthalate is preferable.
In addition to the aromatic dicarboxylic acid component and the diol component, the aromatic polyester resin includes, for example, tricarboxylic acids such as tricarboxylic acids such as trimellitic acid and tetracarboxylic acids such as pyromellitic acid, and trivalent or higher polyvalent carboxylic acids thereof. It may contain an anhydride, a triol such as glycerin, a trivalent or higher polyvalent alcohol such as tetraol such as pentaerythritol, or the like as a constituent component.

When polyethylene terephthalate or the like is used as the polyester resin, it may be crosslinked with a crosslinking agent. Known cross-linking agents are used, and examples thereof include acid dianhydrides such as pyromellitic anhydride, polyfunctional epoxy compounds, oxazoline compounds, and oxazine compounds. The cross-linking agent may be used alone or in combination of two or more.

Examples of the polyamide-based resin include polyamides, polyamide copolymers, and mixtures thereof.
The polyamide resin may be used alone or in combination of two or more.

Examples of the polyamide include nylon 66, nylon 610, nylon 612, nylon 46, nylon 1212, etc. obtained by polycondensation of diamine and dicarboxylic acid; nylon 6, nylon 12, etc. obtained by ring-open polymerization of lactam. ; Etc. can be mentioned.

Examples of the polyamide copolymer include nylon 6/66, nylon 66/6, nylon 66/610, nylon 66/612, nylon 66 / 6T (T represents a terephthalic acid component), and nylon 66 / 6I (T). I represents an isophthalic acid component), nylon 6T / 6I, and the like. Of these, aliphatic polyamides are preferable, and nylon 6, nylon 66, nylon 6/66, nylon 66/6 and the like are more preferable.

Examples of the mixture of the polyamide resin include a mixture of nylon 66 and nylon 6, a mixture of nylon 66 and nylon 612, a mixture of nylon 66 and nylon 610, a mixture of nylon 66 and nylon 6I, and nylon 66. Examples thereof include a mixture of nylon 6T and a mixture of nylon 6 and nylon 6I / 6T. Above all, from the viewpoint of increasing the crystallinity of the foamed resin and sufficiently improving the heat resistance and the surface cosmetic property of the composite, the polyamide-based resin in the case of the mixture preferably contains more than 50% by mass of the aliphatic polyamide. , 60% by mass or more is more preferable.
In the molecule of the polyamide resin, such a substituent is used by using a compound or a polymer having a substituent (hereinafter, also referred to as a reactive substituent) that reacts with an amino group or a carboxyl group of the polyamide resin. The degree of cross-linking of the polyamide-based resin may be increased by forming a cross-linked structure via the above.

Examples of the reactive substituent include functional groups such as glycidyl group, carboxyl group, carboxylic acid metal salt, ester group, hydroxyl group, amino group and carbodiimide group, and particularly from the viewpoint of reaction speed. , Glysidyl group and carbodiimide group are preferable.
The above-mentioned reactive substituents may be used alone or in combination of two or more. Further, a compound having a reactive substituent, a polymer, or the like may have a plurality of types of functional groups in one molecule.
The amount of the reactive substituent introduced into the polyamide resin should be such that gelation or the like does not occur in the resin due to cross-linking.

The highly reactive functional groups (amino group and carboxyl group) of the polyamide resin at the ends are changed to low reactive functional groups by adding an end-capping agent in the synthesis of the polyamide resin (polyamide resin). Can be closed).
In this case, the time for adding the end-capping agent includes the time when the raw material is charged, the time when the polymerization is started, the time when the polymerization is in the middle stage, or the time when the polymerization is completed.

The terminal encapsulant is not particularly limited as long as it is a monofunctional compound capable of reacting with an amino group or a carboxyl group of a polyamide resin, and is not particularly limited, for example, monocarboxylic acid, monoamine, or acid anhydride. Examples include substances, monoisocyanates, monoacid halides, monoesters, monoalcohols and the like. The end sealant may be used alone or in combination of two or more.
In particular, when used in a high temperature environment, a heat stabilizer may be used together with the foamed resin, and in particular, the heat stabilizer effectively prevents long-term heat aging in a high temperature environment of 120 ° C. or higher. From the viewpoint, a copper compound is preferable, and a combination of this copper compound and an alkali metal halide compound is also preferable. Here, examples of the alkali metal halide compound include lithium chloride, lithium bromide, lithium iodide, sodium fluoride, sodium chloride, sodium bromide, sodium iodide, potassium fluoride, potassium chloride, potassium bromide, and iodide. Examples include potassium. These may be used individually by 1 type, and may be used in combination of 2 or more type.

［式中、Ｒ₁、Ｒ₂、Ｒ₃、及びＲ₄は、それぞれ独立して、水素原子；ハロゲン原子；アルキル基；アルコキシ基；フェニル基；ハロゲン原子と一般式（１）中のベンゼン環との間に少なくとも２個の炭素原子を有するハロアルキル基又はハロアルコキシ基で第３α−炭素を含まない基；からなる群から選択される一価の基である。］ The polyphenylene ether (PPE) -based resin refers to a polymer containing a repeating unit represented by the following general formula (1), for example, a homopolymer composed of a repeating unit represented by the following general formula (1), the following. Examples thereof include a copolymer containing a repeating unit represented by the general formula (1).

[In the formula, R ₁ , R ₂ , R ₃ , and R ₄ are independently hydrogen atom; halogen atom; alkyl group; alkoxy group; phenyl group; halogen atom and the benzene ring in the general formula (1). It is a monovalent group selected from the group consisting of a haloalkyl group having at least two carbon atoms or a haloalkoxy group containing no 3α-carbon; ]

The polyphenylene ether-based resin is not particularly limited, and for example, poly (2,6-dimethyl-1,4-phenylene) ether, poly (2,6-diethyl-1,4-phenylene) ether, poly (2-). Methyl-6-ethyl-1,4-phenylene) ether, poly (2-methyl-6-propyl-1,4-phenylene) ether, poly (2,6-dipropyl-1,4-phenylene) ether, poly (2,6-dipropyl-1,4-phenylene) ether, poly ( 2-Ethyl-6-propyl-1,4-phenylene) ether, poly (2,6-dibutyl-1,4-phenylene) ether, poly (2,6-dilauryl-1,4-phenylene) ether, poly (2,6-dilauryl-1,4-phenylene) ether, poly (2,6-dilauryl-1,4-phenylene) ether, poly (2,6-dilauryl-1,4-phenylene) ether, poly (2,6-dilauryl-1,4-phenylene) ether. 2,6-diphenyl-1,4-diphenylene) ether, poly (2,6-dimethoxy-1,4-phenylene) ether, poly (2,6-diethoxy-1,4-phenylene) ether, poly (2-) Methoxy-6-ethoxy-1,4-phenylene) ether, poly (2-ethyl-6-stearyloxy-1,4-phenylene) ether, poly (2,6-dichloro-1,4-phenylene) ether, poly (2-Methyl-6-phenyl-1,4-phenylene) ether, poly (2,6-dibenzyl-1,4-phenylene) ether, poly (2-ethoxy-1,4-phenylene) ether, poly (2) Examples thereof include −chloro-1,4-phenylene) ether and poly (2,6-dibromo-1,4-phenylene) ether. Among them, in particular, in the above general formula (1), R ₁ and R ₂ are alkyl groups having 1 to 4 carbon atoms, and R ₃ and R ₄ are hydrogen atoms or alkyl groups having 1 to 4 carbon atoms. A polymer containing is preferable.
The polyphenylene ether-based resin may be used alone or in combination of two or more.

The polyphenylene ether-based resin may be used in combination with other resins, and is preferably 40 to 80% by mass, more preferably 40 to 70% by mass, based on 100% by mass of the resin component of the foamed resin. %. When the PPE content is 40% by mass or more, excellent heat resistance can be obtained, and when the PPE content is 80% by mass or less, excellent processability can be obtained.

Examples of other resins used together with the polyphenylene ether-based resin include thermoplastic resins and the like, and examples thereof include polyolefin-based resins such as polyethylene, polypropylene, and EVA (ethylene-vinyl acetate copolymer); polyvinyl alcohol; polyvinyl chloride; Polyvinylidene chloride; ABS (acrylonitrile-butadiene-styrene) resin; AS (acrylonitrile-styrene) resin; polystyrene resin; methacrylic resin; polyamide resin; polycarbonate resin; polyimide resin; polyacetal resin; polyester resin; Acrylic resin; Cellulosic resin; Polystyrene-based, Polyvinyl chloride-based, Polyurethane-based, Polyester-based, Polyamide-based, 1,2-Polybutadiene-based, Fluoro-rubber-based thermoplastic elastomer; Polyamide-based, Polyacetal-based, Polyester-based, Fluorine-based thermoplastic engineering plastics; and the like. Further, a modified or crosslinked resin may be used as long as the object of the present invention is not impaired. Of these, polystyrene resins are preferable from the viewpoint of compatibility.
The other resins may be used alone or in combination of two or more.

Examples of the polystyrene-based resin in other resins used together with the polyphenylene ether-based resin include homopolymers of styrene or styrene derivatives, copolymers containing styrene and / or styrene derivatives as main components, and the like. Here, "mainly composed" means that the content of the structural unit derived from styrene and / or the styrene derivative is 60% by mass or more with respect to the total amount of the copolymer (100% by mass).

The styrene derivative is not particularly limited, but is, for example, o-methylstyrene, m-methylstyrene, p-methylstyrene, t-butylstyrene, α-methylstyrene, β-methylstyrene, diphenylethylene, chlorostyrene, bromo. Examples include styrene.

Examples of homopolymers of styrene or styrene derivatives include polystyrene, polyα-methylstyrene, polychlorostyrene and the like.

Examples of the copolymer containing styrene and / or a styrene derivative as a main component include a styrene-α-olefin copolymer; a styrene-butadiene copolymer; a styrene-acrylonitrile copolymer; a styrene-maleic acid copolymer; Styrene-maleic anhydride copolymer; styrene-maleimide copolymer; styrene-N-phenylmaleimide copolymer; styrene-N-alkylmaleimide copolymer; styrene-N-alkyl substituted phenylmaleimide copolymer; styrene- Acrylic acid copolymer; Styrene-methacrylic acid copolymer; Styrene-methylacrylate copolymer; Styrene-methylmethacrylate copolymer; Styrene-n-alkylacrylate copolymer; Styrene-n-alkylmethacrylate copolymer; Ethylvinylbenzene-divinylbenzene copolymer; ternary copolymer such as ABS, butadiene-acrylonitrile-α-methylbenzene copolymer; styrene graft polyethylene, styrene graft ethylene-vinyl acetate copolymer, (styrene-acrylic acid) ) Graft copolymers such as graft polyethylene and styrene graft polyamide; and the like. These may be used individually by 1 type, or may be used in combination of 2 or more type. Further, the polystyrene resin may be used by adding a rubber component such as butadiene, if necessary. The content of the rubber component is preferably 1.0 to 20% by mass, and may be, for example, 6% by mass with respect to 100% by mass of the polystyrene-based resin.

As the polycarbonate-based resin in other resins used together with the above-mentioned polyphenylene ether-based resin, in addition to those obtained by reacting a dihydroxy compound and a carbonate precursor by an interfacial polycondensation method or a molten ester exchange method, a carbonate prepolymer is solid-phased. Examples thereof include those obtained by polymerizing by an ester exchange method and those obtained by polymerizing a cyclic carbonate compound by a ring-opening polymerization method. The dihydroxy component used here may be any as long as it is used as the dihydroxy component of aromatic polycarbonate, and may be bisphenols or aliphatic diols.

Examples of bisphenols include 4,4'-dihydroxybiphenyl, bis (4-hydroxyphenyl) methane, 1,1-bis (4-hydroxyphenyl) ethane, and 1,1-bis (4-hydroxyphenyl) -1-. Phenylethane, 2,2-bis (4-hydroxyphenyl) propane, 2,2-bis (4-hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxyphenyl) -3,3,5 -Trimethylcyclohexane, 2,2-bis (4-hydroxy-3,3'-biphenyl) propane, 2,2-bis (4-hydroxy-3-isopropylphenyl) propane, 2,2-bis (3-t-) Butyl-4-hydroxyphenyl) propane, 2,2-bis (4-hydroxyphenyl) butane, 2,2-bis (4-hydroxyphenyl) octane, 2,2-bis (3-bromo-4-hydroxyphenyl) Propane, 2,2-bis (3,5-dimethyl-4-hydroxyphenyl) propane, 2,2-bis (3-cyclohexyl-4-hydroxyphenyl) propane, 1,1-bis (3-cyclohexyl-4-hydroxyphenyl) Hydroxyphenyl) cyclohexane, bis (4-hydroxyphenyl) diphenylmethane, 9,9-bis (4-hydroxyphenyl) fluorene, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, 1,1-bis ( 4-Hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) cyclopentane, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxy-3,3'-dimethyldiphenyl ether, 4,4'-sulfonyl Diphenol, 4,4'-dihydroxydiphenylsulfoxide, 4,4'-dihydroxydiphenylsulfide, 2,2'-dimethyl-4,4'-sulfonyldiphenol, 4,4'-dihydroxy-3,3'-dimethyl Diphenyl sulfoxide, 4,4'-dihydroxy-3,3'-dimethyldiphenylsulfide, 2,2'-diphenyl-4,4'-sulfonyldiphenol, 4,4'-dihydroxy-3,3'-diphenyldiphenylsulfoxide , 4,4'-Dihydroxy-3,3'-diphenyldiphenylsulfide, 1,3-bis {2- (4-hydroxyphenyl) propyl} benzene, 1,4-bis {2- (4-hydroxyphenyl) propyl } Benzene, 1,4-bis (4-hydroxyphenyl) cyclohexane , 1,3-bis (4-hydroxyphenyl) cyclohexane, 4,8-bis (4-hydroxyphenyl) tricyclo [5.2.1.0 (2,6)] decan, 4,4'-(1, 3-adamantandiyl) diphenol, 1,3-bis (4-hydroxyphenyl) -5,7-dimethyladamantan and the like can be mentioned.

Examples of aliphatic diols include 2,2-bis- (4-hydroxycyclohexyl) -propane, 1,14-tetradecanediol, octaethylene glycol, 1,16-hexadecanediol, and 4,4'-bis (2-). Hydroxyethoxy) biphenyl, bis {(2-hydroxyethoxy) phenyl} methane, 1,1-bis {(2-hydroxyethoxy) phenyl} ethane, 1,1-bis {(2-hydroxyethoxy) phenyl} -1- Phenylethane, 2,2-bis {(2-hydroxyethoxy) phenyl} propane, 2,2-bis {(2-hydroxyethoxy) -3-methylphenyl} propane, 1,1-bis {(2-hydroxyethoxy) ) Phenyl} -3,3,5-trimethylcyclohexane, 2,2-bis {4- (2-hydroxyethoxy) -3,3'-biphenyl} propane, 2,2-bis {(2-hydroxyethoxy)- 3-Isopropyl} propane, 2,2-bis {3-t-butyl-4- (2-hydroxyethoxy) phenyl} propane, 2,2-bis {(2-hydroxyethoxy) phenyl} butane, 2,2 -Bis {(2-hydroxyethoxy) phenyl} -4-methylpentane, 2,2-bis {(2-hydroxyethoxy) phenyl} octane, 1,1-bis {(2-hydroxyethoxy) phenyl} decan, 2 , 2-bis {3-bromo-4- (2-hydroxyethoxy) phenyl} propane, 2,2-bis {3,5-dimethyl-4- (2-hydroxyethoxy) phenyl} propane, 2,2-bis {3-Cycloxyl-4- (2-hydroxyethoxy) phenyl} propane, 1,1-bis {3-cyclohexyl-4- (2-hydroxyethoxy) phenyl} cyclohexane, bis {(2-hydroxyethoxy) phenyl} diphenylmethane , 9,9-bis {(2-hydroxyethoxy) phenyl} fluorene, 9,9-bis {4- (2-hydroxyethoxy) -3-methylphenyl} fluorene, 1,1-bis {(2-hydroxyethoxy) ) Phenyl} cyclohexane, 1,1-bis {(2-hydroxyethoxy) phenyl} cyclopentane, 4,4'-bis (2-hydroxyethoxy) diphenyl ether, 4,4'-bis (2-hydroxyethoxy) -3 , 3'-dimethyldiphenyl ether, 1,3-bis [2-{(2-hydroxyethoxy) phenyl} propyl] benzene, 1 , 4-bis [2-{(2-hydroxyethoxy) phenyl} propyl] benzene, 1,4-bis {(2-hydroxyethoxy) phenyl} cyclohexane, 1,3-bis {(2-hydroxyethoxy) phenyl} Cyclohexane, 4,8-bis {(2-hydroxyethoxy) phenyl} tricyclo [5.2.1.0 (2,6)] decane, 1,3-bis {(2-hydroxyethoxy) phenyl} -5, 7-Dimethyladamantan, 3,9-bis (2-hydroxy-1,1-dimethylethyl) -2,4,8,10-tetraoxaspiro (5,5) undecane, 1,4: 3,6-dianhydro Examples thereof include −D-sorbitol (isosorbide), 1,4: 3,6-dianhydro-D-mannitol (isomannide), 1,4: 3,6-dianhydro-L-iditol (isoidide) and the like. Among these, aromatic bisphenols are preferable, and among them, 1,1-bis (4-hydroxyphenyl) -1-phenylethane, 2,2-bis (4-hydroxyphenyl) propane, and 2,2-bis (4). -Hydroxy-3-methylphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 1,1-bis (4-hydroxyphenyl) -3,3,5-trimethylcyclohexane, 4,4'-sulfonyl Diphenol, 2,2'-dimethyl-4,4'-sulfonyldiphenol, 9,9-bis (4-hydroxy-3-methylphenyl) fluorene, 1,3-bis {2- (4-hydroxyphenyl) Propyl} benzene and 1,4-bis {2- (4-hydroxyphenyl) propyl} benzene are preferred. In particular 2,2-bis (4-hydroxyphenyl) propane, 1,1-bis (4-hydroxyphenyl) cyclohexane, 4,4'-sulfonyldiphenol and 9,9-bis (4-hydroxy-3-methyl) Phenyl) fluorene is preferred. Of these, 2,2-bis (4-hydroxyphenyl) propane, which has excellent strength and good durability, is most preferable. Moreover, these may be used individually or in combination of 2 or more types. Further, the polycarbonate resin may be a branched polycarbonate resin by using a branching agent in combination with the above dihydroxy compound.

Examples of the trifunctional or higher-functional polyfunctional aromatic compound as a branching agent used in such a branched polycarbonate resin include fluoroglucolcin, fluoroglucolside, and 4,6-dimethyl-2,4,6-tris (4-hydrokidiphenyl). Hepten-2,2,4,6-trimethyl-2,4,6-tris (4-hydroxyphenyl) heptane, 1,3,5-tris (4-hydroxyphenyl) benzene, 1,1,1-tris (1,1,1-tris) 4-Hydroxyphenyl) ethane, 1,1,1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane, 2,6-bis (2-hydroxy-5-methylbenzyl) -4-methylphenol, 4 − {4- [1,1-bis (4-hydroxyphenyl) ethyl] benzene} -Trisphenols such as α and α-dimethylbenzylphenol can be mentioned. Also, tetra (4-hydroxyphenyl) methane, bis (2,4-dihydroxyphenyl) ketone, 1,4-bis (4,4-dihydroxytriphenylmethyl) benzene, or trimellitic acid, pyromellitic acid, benzophenone tetracarboxylic acid. Acids and their acid chlorides and the like can be mentioned. Of these, 1,1,1-tris (4-hydroxyphenyl) ethane and 1,1,1-tris (3,5-dimethyl-4-hydroxyphenyl) ethane are preferable, and 1,1,1-tris (4-hydroxyphenyl) ethane is particularly preferable. Hydroxyphenyl) ethane is preferred. Further, regarding the polycarbonate resin, the end may be sealed with phenol or the like.

The (meth) acrylic resin is produced by polymerizing a (meth) acrylic monomer. The (meth) acrylic means either one or both of acrylic and methacryl.
The (meth) acrylic resin may be used alone or in combination of two or more.

The (meth) acrylic monomer is not particularly limited, and (meth) acrylic acid, methyl (meth) acrylate, ethyl (meth) acrylate, butyl (meth) acrylate, lauryl (meth) acrylate, ( Examples thereof include 2-ethylhexyl acrylate, cyclohexyl (meth) acrylate, benzyl (meth) acrylate, and (meth) acrylamide.
Further, the (meth) acrylic resin may contain a monomer component copolymerizable with the (meth) acrylic monomer in addition to the (meth) acrylic monomer. Examples of such a monomer include maleic acid, maleic anhydride, fumaric acid, itaconic acid, itaconic anhydride, crotonic acid, maleic acid amide, and maleic acid imide.
Furthermore, by performing a dehydration reaction, a deethanolation reaction, and an amine exchange reaction using heat and, if necessary, a salt, an alkali, or an acid, a glutaric anhydride, a (meth) acrylicimide ring, or a lactone ring can be added to the main chain. By introducing it, heat resistance may be imparted. Particularly preferably, a methacrylicimide-based resin, a copolymer resin of maleic anhydride and (meth) acrylic and styrene, and the like can be mentioned.

The foamed resin may further optionally contain other components such as additives, a trace amount of gas, and the like. Other components that may be contained in the foamed resin include stabilizers, impact modifiers, flame retardants, lubricants, pigments, dyes, weather resistance improvers, antistatic agents, impact modifiers, crystal nucleating agents, and glass. Examples thereof include beads, an inorganic filler, a cross-linking agent, a nucleating agent such as talc, and other thermoplastic resins, and may be added as long as the object of the present invention is not impaired. The content of the other components in the foamed resin may be 30 parts by mass or less, preferably 25 parts by mass or less, and more preferably 20 parts by mass or less with respect to 100 parts by mass of the foamed resin.

In particular, the stabilizer is not particularly limited, and for example, organic antioxidants such as hindered phenolic antioxidants, sulfur-based antioxidants, phosphorus-based antioxidants, phosphite compounds, and thioether-based compounds. Agents and heat stabilizers; light stabilizers such as hindered amines, benzophenones and imidazoles; ultraviolet absorbers; metal deactivators and the like.
These may be used individually by 1 type, and may be used in combination of 2 or more type.

The trace gas that may be contained in the foamed resin is one that is contained in the foamed resin manufacturing process (described later). The gas is not particularly limited, and examples thereof include air, carbon dioxide gas, various gases used as a foaming agent, an aliphatic hydrocarbon-based gas, and alcohol. Specific examples of the aliphatic hydrocarbon gas include butane and pentane. Examples of the alcohol include methanol, ethanol, butanol, pentanol and the like.
The content of the trace gas is preferably less than 0.1% by mass, more preferably 0.07% by mass or less, and particularly preferably not contained in 100% by mass of the core material. It is preferable that the amount of gas is small because it is possible to prevent the foamed resin from swelling due to the influence of the gas in an environment of 100 ° C. when the fiber complex is formed, and the appearance is preferable.

Further, the foamed resin may contain other thermoplastic resins. Examples of other thermoplastic resins include polyolefin resins such as polyethylene, polypropylene, and EVA (ethylene-vinyl acetate copolymer); polyvinyl alcohol; polyvinyl chloride; polyvinylidene chloride; polycarbonate resin; polyimide resin; polyacetal. Resins; Cellulosic resins; Polyvinyl chloride-based, Polyurethane-based, Polyester-based, 1,2-polybutadiene-based, Fluoro-rubber-based thermoplastic elastomers; Polyacetal-based, Polyester-based, Fluorine-based thermoplastic engineering plastics; etc. Can be mentioned. Further, a modified or crosslinked resin may be used as long as the object of the present invention is not impaired. These may be used individually by 1 type, or may be used in combination of 2 or more type.

-Resin part (A)-
The core material contains a resin portion (A) and air bubbles (C), and preferably further contains a resin portion (B). The core material may have a structure other than the resin portion (A), the resin portion (B), and the air bubbles (C).

The resin portion (A) contained in the core material of the present embodiment is a substantially solid resin portion having a width of 8 μm or more in a cross section obtained by cutting the fiber composite in the thickness direction. Is preferable. When the width of the resin portion (A) is 8 μm or more, the rigidity of the fiber composite in a high temperature environment is high, which is preferable. It is more preferably 9 μm or more, still more preferably 12 μm or more.
Here, the width of the resin portion (the width of the resin portion at an arbitrary point a on the outer circumference of the bubble) means the distance between the outer circumferences of the adjacent bubbles, specifically, on the outer circumference of the bubble in the above cross section. The length of the line segment connecting two points whose minimum distance is the length of the line segment connecting the point a and the point b on the outer circumference of the bubble adjacent to the bubble. However, it is assumed that the line segment passes only through the resin portion and the bubble (C) does not pass through. When the width of the resin portion at the point a on the outer periphery of the bubble is 8 μm or more, it is preferable that the width of the resin portion at the point a and the width of the resin portion at the point b are both 8 μm or more.

The resin constituting the resin portion (A) may be the same as or different from the foamed resin. The width of the resin portion (A) and the major axis of the bubbles are measured by the method described in Examples described later.

From the viewpoint of further excellent rigidity in a high temperature environment, the resin portion (A) preferably has a width of 8 μm or more continuously of 1 mm or more, more preferably 5 mm or more, and foaming. It is more preferable that it lasts at least the thickness of the body, and it is particularly preferable that it lasts at least 1.5 times the thickness of the foam. Above all, the point where the width of the resin portion is 8 μm or more is preferably continuously 1 mm or more in the thickness direction, and more preferably 5 mm or more. Further, it is preferable that it continues by 50% or more with respect to 100% of the thickness of the foam, and more preferably 100% continuously in the thickness direction.

The average width of the resin portion (A) contained in the core material is preferably 8 to 40 μm from the viewpoint of further excellent rigidity in a high temperature environment.
The average width of the resin portion (A) can be measured by the method described in Examples described later.

In the cross section of the resin portion (A), it is preferable that at least a part of the resin portion (A) is continuously connected from one surface of the core material on which the skin material is laminated to the other surface. By continuously connecting the wide resin portions (A) in this way, the structure of the core material as a structural material can be formed by the thick resin portion (A), and the thick resin portion (A) can be formed even at a high temperature. ) Plays a role as a support material, so that the bending strength of the core material of the fiber composite can be maintained, which is preferable.
In the above cross section, the resin portion (A) may be continuously connected in a linear shape in the thickness direction, or may be continuously connected in a curved shape. Above all, from the viewpoint of further excellent rigidity in a high temperature environment, it is preferable to have a plurality of resin portions (A) that are continuously connected in the thickness direction, and a resin that is continuously connected in the thickness direction in a linear and / or curved shape. It is more preferable to have a network structure (see FIG. 1) having a plurality of portions (A) and connecting these resin portions in the width direction (direction orthogonal to the thickness direction in the cross section). The network structure may be a part of the core material of the cross section, or may be the entire core material.

From the viewpoint of further excellent rigidity in a high temperature environment, it is preferable that the interface between the core material and the skin material contains a resin portion (A) in the above cross section, and the entire surface may be a resin portion (A). (See FIG. 1), and a part of the resin portion (A) may be used.
Further, in the above cross section, the interface between the core material and air (both ends in the width direction of the cross section, etc.) may include a resin portion (A), or the entire surface may be a resin portion (A). (See FIG. 1), and a part of the resin portion (A) may be used.

-Resin part (B)-
The resin portion (B) is a resin portion having a width of 6 μm or less. The resin portion (B) shows a partition wall between bubbles contained in the core material and corresponds to a wall surface of the bubbles. When the width of the resin portion (B) is 6 μm or less, the distance between the bubbles is short, it means that the bubbles are densely present in the core material, and it is lightweight and the rigidity at high temperature is uniform, which is preferable. It is more preferably 5 μm or less, still more preferably 4 μm or less. The method for measuring the width of the resin portion (B) is the method described in Examples described later.

The average width of the resin portion (B) contained in the core material is preferably 0.6 to 6 μm from the viewpoint of further excellent rigidity in a high temperature environment.
The average width of the resin portion (B) can be measured by the method described in Examples described later.
The average width of the resin portion (A) and the resin portion (B) in the present specification means a value obtained from any 30 resin portions whose widths satisfy a specific range.

-Bubble (C)-
The average major axis of the bubble (C) is preferably 5 to 800 μm, more preferably 10 to 700 μm. When the average major axis of the bubbles is in this range, it is preferable that the impact energy can be sufficiently absorbed, especially in a high temperature environment of 100 ° C.
In this specification, the average major axis of bubbles means a value measured by the method described in Examples described later. The average major axis in the present specification means a value obtained from any 30 bubbles whose average major axis satisfies a specific range.

In the above cross section, it is preferable to include a structure in which a plurality of bubbles (C) are surrounded by a resin portion (A). It is preferable that the resin portion (B) and the bubbles (C) in the core material of the present embodiment are surrounded by the resin portion (A). A core material containing a thin resin portion (B) and air bubbles (C) and not containing the resin portion (A) is generally easily broken at a high temperature and has low strength. By being surrounded by the thick resin portion (A), when stress is applied to the fiber complex at a high temperature, the resin portion (A) can withstand the stress, which is preferable. Further, it is more preferable that the resin portion (B) and the air bubbles (C) are surrounded by the resin portion (A) finely pasted around in the core material in a mesh pattern. The unit surrounded by the resin portion (A) preferably has a major axis of 100 μm to 3 mm, more preferably 300 μm to 3 mm.

The resin constituting the resin portion (A) and the resin portion (B) in the core material may be the same or may be different.
As a method for producing the fiber composite of the present embodiment, a foamed resin composed of a resin portion (B) and bubbles (C) may be packed between the mesh-like resin portions (A) prepared above, or the resin portion ( The resin portion (A) may be formed by laminating the foamed resin composed of B) and the bubbles (C) with the resin which is the raw material of the resin portion (A), or the resin portion (B) and the bubbles (C) may be formed. A resin portion (A) may be formed by welding a foamed resin made of the above material to remove air bubbles.

The apparent density of the core material is preferably from 10~700kg / m ^3, more preferably 20~600kg / m ^3. If the apparent density is moderate, stress concentration parts are less likely to occur due to buckling of bubbles when a strong impact is applied to the fiber composite, especially even in a high temperature environment such as 100 ° C, and the skin material is easy to use. It is preferable because there is little risk of deformation and destruction. It is also preferable for the purpose of weight reduction.
In the present specification, the apparent density means a value measured by the method described in Examples described later, which is obtained from the measured volume and weight by cutting out only the core material from the fiber-reinforced composite.

(Skin material)
The skin material containing fibers and resins used in the fiber composite of the present embodiment is preferably made by impregnating reinforcing fibers with a reinforcing synthetic resin.

The skin material does not have to be laminated and integrated on both surfaces of the core material, as long as the skin material is laminated and integrated on at least one surface of the core material. The lamination of the skin material may be determined according to the use of the fiber composite. Above all, in consideration of the impact resistance of the fiber composite, it is preferable that the skin material is laminated and integrated on each surface of the upper and lower surfaces in the thickness direction of the core material. As shown in FIG. 1, such a fiber composite 1 has a core material 2 made of a foamed resin and a skin material 3 laminated and integrated on both sides of the core material 2.

The fibers constituting the skin material are preferably reinforcing fibers. Reinforcing fibers include inorganic fibers such as glass fibers, carbon fibers, silicon carbide fibers, alumina fibers, tyranno fibers, genbuiwa fibers, and ceramics fibers; metal fibers such as stainless steel fibers and steel fibers; aramid fibers, polyethylene fibers, and polyparaphenylene. Organic fibers such as benzoxador (PBO) fibers; boron fibers and the like can be mentioned. The reinforcing fibers may be used alone or in combination of two or more. Among them, carbon fiber, glass fiber and aramid fiber are preferable, and carbon fiber is more preferable. These reinforcing fibers have excellent mechanical strength in spite of being lightweight.

The reinforcing fiber is preferably used as a reinforcing fiber base material processed into a desired shape. Examples of the reinforcing fiber base material include woven fabrics made of reinforcing fibers, knitted fabrics, non-woven fabrics, and face materials made by binding (sewn) fiber bundles (strands) in which reinforcing fibers are aligned in one direction with threads. .. Examples of the weaving method of the woven fabric include plain weave, twill weave, satin weave and the like. Examples of the thread used for bundling the fiber bundles include synthetic resin threads such as polyamide resin threads and polyester resin threads, and stitch threads such as glass fiber threads.

As the reinforcing fiber base material, only one reinforcing fiber base material may be used, or a plurality of reinforcing fiber base materials may be laminated and used as a laminated reinforcing fiber base material. As the laminated reinforcing fiber base material, (1) a plurality of laminated reinforcing fiber base materials prepared by preparing only one kind of reinforcing fiber base material and laminating these reinforcing fiber base materials, and (2) a plurality of types of reinforcing fiber base materials. , And multiple laminated reinforcing fiber base materials in which these reinforcing fiber base materials are laminated, and (3) a plurality of face materials made by binding (sewn) fiber bundles (strands) in which reinforcing fibers are aligned in one direction with a thread. A laminated reinforcing fiber base material, etc., which is prepared by preparing a sheet, superimposing these face materials so that the fiber directions of the fiber bundles are directed to different directions, and integrating (sewn) the superposed face materials with a thread. Can be mentioned. Examples of the thread used when integrating the face materials include synthetic resin threads such as polyamide resin threads and polyester resin threads, and stitch threads such as glass fiber threads.

The skin material is preferably a reinforcing fiber impregnated with a reinforcing resin. The impregnated reinforcing resin can bind and integrate the reinforcing fibers. As the reinforcing resin to be impregnated with the reinforcing fibers, either a thermoplastic resin or a thermosetting resin can be used, and the thermosetting resin is preferably used. The reinforcing resin may be used alone or in combination of two or more.

The thermosetting resin is not particularly limited, and for example, a thermosetting epoxy resin, an unsaturated polyester resin, a phenol resin, a melamine resin, a thermosetting polyurethane resin, a silicon resin, a maleimide resin, a vinyl ester resin, and a cyanate ester. Examples thereof include a resin, a resin obtained by prepolymerizing a maleimide resin and a cyanate ester resin, and the like, and an epoxy resin and a vinyl ester resin are preferable because they are excellent in heat resistance, shock absorption or chemical resistance. The thermosetting resin may contain additives such as a curing agent and a curing accelerator.

The thermoplastic resin is not particularly limited, and examples thereof include an olefin resin, a polyester resin, a thermoplastic epoxy resin, an amide resin, a thermoplastic polyurethane resin, a sulfide resin, an acrylic resin, and the like, and adhesion to a foam. Polyester-based resins and thermoplastic epoxy resins are preferable because they have excellent properties or adhesiveness between the reinforcing fibers constituting the fiber-reinforced plastic layer and also have high heat resistance.

The epoxy resin as the thermoplastic resin includes a polymer or a copolymer of epoxy compounds having a linear structure, an epoxy compound, and a monomer capable of polymerizing with the epoxy compound. Examples thereof include a copolymer which is a copolymer and has a linear structure. Specifically, for example, bisphenol A type epoxy resin, bisphenol fluorene type epoxy resin, cresol novolac type epoxy resin, phenol novolac type epoxy resin, cyclic aliphatic type epoxy resin, long chain aliphatic type epoxy resin, glycidyl ester type epoxy. Examples thereof include a resin and a glycidylamine type epoxy resin, and a bisphenol A type epoxy resin and a bisphenol fluorene type epoxy resin are preferable.

Examples of the polyurethane resin as the thermoplastic resin include a polymer having a linear structure obtained by polymerizing a diol and a diisocyanate.
Examples of the diol include ethylene glycol, diethylene glycol, propylene glycol, dipropylene glycol, 1,3-butanediol, and 1,4-butanediol. The diol may be used alone or in combination of two or more.
Examples of the diisocyanate include aromatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates. The diisocyanate may be used alone or in combination of two or more.

The content of the resin (preferably a synthetic resin for strengthening) in the skin material is preferably 20 to 70% by mass, more preferably 30 to 60% by mass, based on 100% by mass of the skin material. If the content of the resin (preferably a synthetic resin for strengthening) is too small, the binding property between the fibers and the adhesiveness between the skin material and the core material become insufficient, and the mechanical strength of the skin material and the fiber composite There is a risk that the impact resistance cannot be sufficiently improved. Further, if the content of the resin is too large, the mechanical strength of the skin material is lowered, and the impact resistance of the fiber composite may not be sufficiently improved. Further, it is preferable that the heat resistance of the resin is high in order to maintain the rigidity at high temperature, but if it is too high, a high temperature is required for bonding, the molding time becomes long, and the productivity is lowered. The heat resistance can be expressed by the glass transition temperature of the resin, and in the case of a thermosetting resin, it is expressed by the glass transition temperature after curing. The preferred glass transition temperature is 70 to 150 ° C, more preferably 75 to 140 ° C. The glass transition temperature can be measured based on JIS K7121.

The thickness of the skin material is preferably 0.02 to 2 mm, more preferably 0.05 to 1 mm per layer. The skin material having a thickness within the above range is excellent in mechanical strength despite being lightweight.

Basis weight of the skin material is preferably ^{50~4000g / m 2, 100~1000g / m} 2 is more preferable. The skin material having a basis weight within the above range is excellent in mechanical strength in spite of being lightweight.

[Production method]
(Manufacturing method of core material)
As a method for producing the core material containing the foamed resin of the present embodiment, a known production method can be used. Specifically, (1) a foamed molded product (foaming) is obtained by filling a mold with foamable resin particles and heating them with steam or the like to foam the resin particles and at the same time heat-sealing the resin particles to each other. Method for producing body) (in-mold foam molding method), (2) Supplying synthetic resin to an extruder, melt-kneading in the presence of a foaming agent such as a chemical foaming agent or a physical foaming agent, and extrusion foaming from the extruder (Extrusion foaming method), (3) Synthetic resin and chemical foaming agent are supplied to the extruder and melt-kneaded at a temperature lower than the decomposition temperature of the chemical foaming agent, and the foamable resin molded product is melted and kneaded from the extruder. , And the foamable resin molded body is foamed to produce a foamed product. Above all, the in-mold foam molding method has advantages such that the product shape can be easily set and a foam molded product having a high foaming ratio can be easily obtained. It is possible to provide the resin portion (A) by post-processing in the extrusion foaming method of (2) and (3), but among them, the in-mold foam molding method of (1) is a preliminary resin portion (preliminary resin portion) due to welding in the resin particles. It is preferable that the precursor of A) is obtained and foamed to obtain the resin portion (B) and bubbles in one molding.

Examples of the resin particles used in the in-mold foam molding method include pre-foamed particles and the like. For example, when producing a polyamide-based resin foam, polyamide-based preliminary foamed particles can be used.
In addition, in this specification, the preliminary foaming particles refer to resin particles (beads, etc.) having foamability that have not been foamed in the final stage.

The pre-foamed particles can be obtained by impregnating (impregnating) a resin that is a raw material of the foamed resin with a foaming agent to cause foaming. For example, the method of containing (impregnating) the foaming agent in the polyamide resin is not particularly limited, and may be a generally used method.

As a method of impregnating the resin with a foaming agent, a method of impregnating the resin with an aqueous medium in a suspension system such as water (suspension impregnation method) or a method of using a heat-decomposable foaming agent such as sodium bicarbonate (foaming agent decomposition method). ), A method in which the gas is brought into a liquid phase state with an atmosphere above the critical pressure and brought into contact with the resin (liquid phase impregnation method), and a method in which the gas is brought into an atmosphere below the critical pressure and brought into a gas phase state and brought into contact with the resin (gas phase). Impregnation method) and the like. As a method for containing a foaming agent, a vapor phase impregnation method is particularly preferable.

Examples of the foaming agent decomposition method include a method using a thermally decomposable foaming agent such as azodicarbonamide, dinitrosopentamethylenetetramine, hydrazoyldicarboxylicamide, and sodium bicarbonate. The thermal decomposition type foaming agent may be used alone or in combination of two or more.

In the gas phase impregnation method, the solubility of the gas in the resin is higher and the content of the foaming agent is likely to be higher than in the case of the suspension impregnation method carried out under high temperature conditions. Therefore, in the vapor phase impregnation method, it is easy to achieve a high foaming ratio, and the bubble size in the preliminary foamed particles tends to be uniform.

Further, the foaming agent decomposition method is also carried out under high temperature conditions like the suspension impregnation method. Further, in this method, not all of the added pyrolyzable foaming agent becomes gas, so that the amount of gas generated tends to be relatively small. Therefore, the vapor phase impregnation method has an advantage that the content of the foaming agent can be easily increased. Further, in the gas phase impregnation method, the equipment such as the pressure resistant device and the cooling device tends to be more compact and the equipment cost can be easily reduced as compared with the case of the liquid phase impregnation method.

The shape of the resin used in the vapor phase impregnation method is not particularly limited, and examples thereof include bead-shaped, pellet-shaped, spherical, and amorphous pulverized products, and the size thereof is pre-foaming after foaming. The average diameter is preferably 0.2 to 3 mm from the viewpoint of making the size of the particles appropriate, improving the ease of handling the pre-foamed particles, and making the filling denser at the time of molding.

The conditions of the gas phase impregnation method are not particularly limited, and for example, the atmospheric pressure may be 0.5 to 6.0 MPa from the viewpoint of more efficiently dissolving the gas in the resin. The atmospheric temperature is preferably 5 to 30 ° C.
Here, the foaming agent used in producing the pre-foamed particles is not particularly limited, and examples thereof include compounds that can be used as air or gas.

Examples of compounds that can be gas include inorganic compounds such as carbon dioxide, nitrogen, oxygen, hydrogen, argon, helium, and neon; trichlorofluoromethane (R11), dichlorodifluoromethane (R12), chlorodifluoromethane (R22), tetra. Fluorocarbons such as chlorodifluoroether (R112), dichlorofluoroethane (R141b), chlorodifluoroethane (R142b), difluoroethane (R152a), HFC-245fa, HFC-236ea, HFC-245ca, HFC-225ca; HFO-1234y, HFO-1234ze. Hydrofluoroolefins such as (E); saturated hydrocarbons such as propane, n-butane, i-butane, n-pentane, i-pentane, neopentane; dimethyl ether, diethyl ether, methyl ethyl ether, isopropyl ether, n-butyl ether, Examples thereof include ethers such as diisopropyl ether, furan, furfural, 2-methylfuran, tetrahydrofuran and tetrahydropyran; chlorinated hydrocarbons such as methyl chloride and ethyl chloride; alcohols such as methanol and ethanol; and the like.
These compounds that can be used as air or gas may be used alone or in combination of two or more.

As the foaming agent, those having little impact on the environment and having no flammability or flammability are preferable, and from the viewpoint of safety during handling, flammable and non-flammable inorganic compounds are more preferable, and the foaming agent is applied to the resin. Carbon dioxide gas (carbon dioxide gas) is particularly preferable from the viewpoint of solubility and ease of handling.

The method for causing foaming in the resin containing (impregnated) the foaming agent (foaming agent impregnated resin) is not particularly limited, but for example, a foaming agent impregnated resin such as a foaming agent impregnated polyamide resin is subjected to low pressure from a high pressure atmosphere. A method of expanding the gas as a foaming agent dissolved in the foaming agent-impregnated resin by bringing it into the atmosphere at once to cause foaming, or a method of heating using pressure steam or the like to heat the foaming agent-impregnated resin. A method of expanding the gas inside to cause foaming can be used, and in particular, the advantage of making the size (cell size) of bubbles inside the molded product, which is a product, uniform, and controlling the foaming ratio. Therefore, it is preferable to use the latter method of heating and foaming, because the advantage of facilitating the production of a molded product having a low foaming ratio can be obtained.

Here, when the pre-foamed particles are foamed to a desired expansion ratio, one-step foaming may be performed, or multi-step foaming including secondary foaming and tertiary foaming may be performed. When multi-step foaming is performed, it is easy to prepare pre-foamed particles having a high foaming ratio, and the pre-foamed particles used for molding are up to tertiary foaming from the viewpoint of reducing the amount of resin used per unit volume. It is preferable that the pre-foamed particles are the same.

In particular, in the case of multi-step foaming, it is preferable to pressurize the pre-foamed particles with gas before foaming at each step. The gas used for the pressure treatment is not particularly limited as long as it is inert to the resin, but an inorganic gas or a hydrofluoroolefin having high gas safety and a small global warming potential of the gas is preferable. Examples of the inorganic gas include air, carbon dioxide gas, nitrogen gas, oxygen gas, ammonia gas, hydrogen gas, argon gas, helium gas, neon gas and the like, and examples of the hydrofluoroolefin include HFO-1234y and the like. Examples thereof include HFO-1234ze (E), and air or carbon dioxide gas is particularly preferable from the viewpoint of ease of handling and economy. The method of the pressure treatment is not particularly limited, and examples thereof include a method of filling the pressure tank with prefoamed particles and supplying gas into the tank.

The foamed resin preferably contains the pre-foamed particles, and can be obtained, for example, by molding the pre-foamed particles. The pre-foamed particles may be used alone or in combination of two or more.

The method for molding the pre-foamed particles is not particularly limited, but for example, the pre-foamed particles are filled in the cavity of the molding die and heated to cause foaming and at the same time heat-melt the pre-foamed particles. After being dressed, the product can be solidified and molded by cooling. Here, the method for filling the pre-foamed particles is not particularly limited, but for example, a cracking method in which the pre-foamed particles are filled with the mold slightly open, or a pre-pressurized and compressed state with the mold closed. Examples thereof include a compression method in which foamed particles are filled, a compression cracking method in which the above-mentioned cracking method is performed after filling a mold with prefoamed particles pressure-compressed.
From the viewpoint of applying a constant gas pressure to the bubbles of the pre-foamed particles to make the size (cell size) of the bubbles inside the particles uniform, before filling the pre-foamed particles into the cavity of the molding mold, It is preferable to pressurize the prefoamed particles with a gas. The gas used for the pressurizing treatment is not particularly limited, and examples thereof include an inorganic gas from the viewpoint of flame retardancy, heat resistance, and dimensional stability. The method of the inorganic gas and the pressure treatment is the same as that of the pressure treatment with the gas applied to the pre-foamed particles in the case of multi-step foaming.

The heat medium used for molding the pre-foamed particles may be a general-purpose heat medium, and is preferably saturated steam or superheated steam from the viewpoint of suppressing oxidative deterioration of the foamed resin, and is uniform with respect to the foamed resin. Saturated steam is more preferred from the viewpoint of enabling heating.

The method for producing the foamed resin is, for example, a filling step of filling the cavity of the prefoamed particles with the prefoamed particles, and supplying water vapor below the heat fusion temperature of the prefoamed particles into the cavity for 5 to 30 seconds. By a preheating step of preheating the prefoamed particles and by supplying water vapor above the heat fusion temperature of the prefoamed particles into the cavity for 20 to 120 seconds to foam and heat-fuse the prefoamed particles. , A method having a fusion step for obtaining a foamed resin is preferable.

Further, the foamed resin is preferably obtained by heating the pre-foamed particles in two steps in a preheating step and a fusion step.

According to this method, in the first step, the prefoamed particles are preheated with steam below the heat fusion temperature of the prefoamed particles to make the temperature distribution in the entire aggregate of the prefoamed particles more uniform. be able to. Then, by the preliminary heating in the first step, when the pre-foamed particles are heated with steam above the heat fusion temperature in the second step, the foaming in the pre-foamed particles becomes more uniform, and the pre-foamed particles become more uniform. Is easy to mold into a foam.

Further, according to this method, in the obtained foamed resin, the crystallinity size of the resin becomes larger, the crystallinity becomes higher, and a core material having excellent heat resistance can be obtained.

As described above, it is desirable that the temperature at which the prefoamed particles are heated is close to the heat fusion temperature (Tf) of the prefoamed particles.
In the present specification, the heat fusion temperature refers to the temperature at which the prefoamed particles are heated in saturated steam and the prefoamed particles are fused to each other. The method for measuring the heat fusion temperature is as described below. In this specification, the heat fusion temperature refers to a value measured by the method described in Examples described later.

The heating temperature in the first step is preferably lower than Tf (° C.), preferably Tf-20 ° C. or higher, more preferably Tf-15 ° C. or higher, and Tf-2 ° C. It is preferably the following, and more preferably Tf-5 ° C. or lower.
The heating time of the first step is preferably 2 seconds or more, more preferably 3 seconds or more, more preferably 20 seconds or less, and further preferably 15 seconds or less.

The heating temperature in the second stage is higher than Tf (° C.), preferably Tf + 15 ° C. or lower, more preferably Tf + 10 ° C. or lower, and particularly preferably Tf + 5 ° C. or lower.
The heating time of the second step is preferably 10 seconds or more, more preferably 15 seconds or more, preferably 60 seconds or less, and further preferably 45 seconds or less.

If the heating temperature and heating time of the first step and the second step are within the above ranges, the pre-foamed particles can be sufficiently heat-sealed, and the foam in which the crystallization of the resin is further promoted can be obtained. Obtainable.

^{The density of the foam before laminating is 20 kg / m 3} or more from the viewpoint of improving the appearance of the foamed resin or the fiber composite by making the strength of the foamed resin appropriate and making it difficult for the bubble film to break. it is preferred, further preferably 50 kg / m ³ or more, from the viewpoint of enhancing the light weight of the fiber composite, is preferably 800 kg / m ³ or less, still be less than 500 kg / m ³ preferable.
The density of the foam can be measured by the method described in Examples described later.

The closed cell ratio S of the foam before laminating improves the strength of the foamed resin and makes it difficult for water to be taken into the foam, which may occur in the open cell portion, so that the density of the foam is less likely to decrease. From the viewpoint, it is preferably 80% or more, and more preferably 85% or more.
The closed cell ratio S (%) is calculated by the formula represented by the following formula (3).
S (%) = {(Vx-W / ρ) / (Va-W / ρ)} x 100 ... (3)
In the formula, Vx is the true volume of the foam (cm ³ ), Va is the apparent volume of the foam (cm ³ ), W is the weight of the foam (g), and ρ is the weight of the foam. , The density of the base resin of the foam (g / cm ³ ).
The closed cell ratio can be measured by cutting the skin material from the fiber complex. In addition, the closed cell ratio can be measured by the method described in Examples described later.

The foam before lamination has a dimensional change rate of 1.5% or less, preferably 1.0% or less, at 150 ° C. from the viewpoint of suppressing deterioration of physical properties and heat shrinkage in a high temperature environment. Is even more preferable.
The dimensional change rate refers to a value measured in accordance with the dimensional stability evaluation method B of JIS K6767.

The expansion ratio of the foam before laminating is preferably 1.3 to 60 times, more preferably 1.5 to 30 times, and even more preferably 5 to 20 times. The foam having a foaming ratio within the above range has an appropriate heat transfer property, whereby a desired wide resin portion (A) is formed in the core material in the compression step during the production of the fiber composite. It becomes easy to form. In the present invention, the foaming ratio of the foam is a value measured in accordance with JIS K7222.

The fusion rate of the foam before laminating is very important for the formation of the resin portion (A), from the viewpoint of increasing the rigidity when stress such as bending strain is applied to the composite, and cutting the foam. From the viewpoint of suppressing the loss of the prefoamed particles from the molded product, the content is preferably 60% or more, more preferably 70% or more, and most preferably 80% or more.
The method for measuring the fusion rate is as described in the examples.

(Manufacturing method of fiber complex)
As a method for producing the fiber composite of the present embodiment, a known thermoforming method can be used, and examples thereof include a vacuum forming method, a pressure molding method, and a compression molding method. As thermoforming methods applying the vacuum forming method and the pneumatic forming method, for example, a straight forming method, a drape forming method, a plug assist forming method, a plug assist / reverse draw forming method, an air slip forming method, a snapback forming method, and a reverse drawing method. Examples thereof include a molding method, a plug-assisted air slip molding method, a match molding method, and a thermoforming method combining these molding methods.

Above all, when the foamed resin obtained by heat fusion foam molding using the preliminary foamed particles is used as the core material, heat and pressure are applied in a mold or a vacuum pack in a negative pressure state. In the method of integration, when voids or the like are present in the precursor of the resin portion (A) generated by heat fusion in advance, the voids are eliminated by heating and vacuum, and the width is substantially preferable. It is preferable because a solid resin portion (A) can be obtained. The vacuum pressure air molding method or the vacuum compression molding method is preferable, and specifically, the autoclave method and the mold cavity vacuum compression molding method are preferable.

An example of a procedure for producing a fiber composite by using a thermoforming method will be specifically described. In the method for producing a fiber composite of the present embodiment, a skin material containing reinforcing fibers impregnated with a reinforcing synthetic resin is laminated on at least a part of at least one surface of a core material (for example, a foam). The temperature of the foamed resin contained in the core material is 50 ° C. lower than the glass transition temperature of the reinforcing synthetic resin and 60 ° C. higher than the glass transition temperature of the reinforcing synthetic resin. A compression process in which the foamed resin contained in the core material is heated at a temperature 50 ° C. lower than the fusion temperature and 20 ° C. higher than the heat fusion temperature of the foamed resin, and is compressed by pressing 0.05 to 1 MPa for simultaneous molding. Examples include a method including. At this time, for example, a vacuum pack containing a laminate may be placed in an autoclave in advance, and heat and pressure (pressure air) may be applied from outside the vacuum pack while reducing the pressure inside the vacuum pack. When using a mold for compression, after putting the laminate in the mold cavity, a mechanism that can seal the O-ring, inro structure, etc. is provided on the parting surface to reduce the pressure inside the mold cavity. The laminate may be heated and compressed on the mold surface.

In the compression step, the foam is preferably compressed so that the compression deformation rate of the foam is 5 to 40%, more preferably more than 25% and less than 40%.
The compression deformation rate means that if the thickness of the molded product before the compression step is 10 mm and the thickness of the molded product after the compression step is 7 mm, the compression deformation rate of this molded product is 30%. The compression deformation rate can be controlled by the heating temperature of the laminate and the pressing force for compression. The heating temperature of the laminated body means the surface temperature of the skin material of the laminated body. When this heating temperature is 50 ° C. lower than the glass transition temperature of the reinforcing synthetic resin and 60 ° C. higher than the glass transition temperature, sufficient curing can be obtained within the curing time, so that the adhesion is improved. However, it is preferable that the rigidity is maintained in a high temperature environment of 100 ° C. Further, the heating temperature is also related to the heat fusion temperature of the foamed resin contained in the core material, and is preferably a temperature 40 ° C. lower than the heat fusion temperature or more and 20 ° C. higher than the heat fusion temperature, which is the condition. It is preferable that the average aspect ratio of the bubbles of the core material and the shape of the bubbles are appropriately maintained, the adhesion of the interface of the laminate becomes very high, and the rigidity is maintained in a high temperature environment of 100 ° C. If compression is performed at a temperature higher than 20 ° C. than the heat fusion temperature of the foamed resin contained in the core material, the core material melts and air bubbles in the core material burst and disappear, which is not preferable. More preferably, the temperature is 30 ° C. lower than the heat fusion temperature of the foamed resin contained in the core material, and 10 ° C. or higher than the heat fusion temperature of the foamed resin contained in the core material.

The pressing force is preferably 0.05 to 1 MPa, more preferably 0.1 to 0.7 MPa. When the pressing is in this range, the surface appearance of the fiber complex is good, the resin portion (A) is thick, and the strength at high temperature is high, which is preferable.

The pressing time depends on the heating temperature, but by removing the voids existing in the core material and continuing to apply pressure while the core material is softened to the extent that bubbles in the foam do not burst, the resin portion Since (A) is formed, it is preferably longer than 1 hour and less than 10 hours.

In the actual state of the present invention, since the core material (preferably a foam) contains air bubbles and therefore has low heat transfer property, it is difficult to heat the central portion of the core material. Therefore, before the compression step, it is preferable to carry out the preheating step on the laminate under the condition that no pressure is applied. By carrying out such a preheating step, it is possible to appropriately soften the inside and the surface of the core material without bubbles breaking. Further, in the compression step, by heating the laminate at a predetermined temperature, the reinforcing synthetic resin impregnated in the reinforcing fibers can be appropriately softened. Then, by compressing the laminate while performing such heating, the core material can be pressed over the entire surface in the thickness direction and the surface direction while the skin material is deformed along the surface of the core material. This makes it possible to further improve the weldability of the prefoamed particles.

When the reinforcing synthetic resin to be impregnated with the reinforcing fibers contains an uncured thermosetting resin, it is preferable to adjust the heating of the laminate in the compression step, preferably to obtain the fiber-reinforced plastic layer forming material. The uncured thermosetting resin is maintained in a fluid state without being cured, the fiber-reinforced plastic layer forming material is deformed along the surface of the foam, and then the heating time of the laminate is adjusted. By advancing the curing reaction of the uncured thermosetting resin, the thermosetting resin can be cured and the reinforcing fibers can be bound and integrated, whereby the thermosetting resin can be combined with the reinforcing fibers on the core material. Can form a skin material impregnated with. When a thermoplastic resin is used as the reinforcing synthetic resin to be impregnated with the reinforcing fibers, the thermoplastic resin is also cooled and solidified by cooling the laminated body after heating the laminated body in the compression step, whereby the thermoplastic resin is used. Reinforcing fibers can be bound and integrated to form a skin material containing a fiber and a resin obtained by impregnating the reinforcing fiber with a thermoplastic resin on the core material.

Further, when the vacuum pack or the mold cavity is depressurized, it is preferable to make the vacuum as much as possible in order to bring the large voids and the skin material in the foamed resin into close contact with the core material and improve the appearance and thickness accuracy. When the inside of the mold cavity is evacuated, the sealing property must be strengthened, and therefore the durability of the mold sealing property is not good. Therefore, the gauge pressure is preferably -0.1 MPa to -0.01 MPa. , More preferably −0.8 MPa to −0.01 MPa.

In the method of the present embodiment, it is preferable to use a laminate in which a fiber reinforced plastic layer forming material containing a reinforcing fiber impregnated with a synthetic resin is laminated on at least one surface of the core material described above. The surface on which the fiber-reinforced plastic layer-forming material is laminated in the core material may be determined according to the use of the obtained fiber composite, and is not particularly limited. Therefore, the fiber reinforced plastic layer forming material may be laminated only on one surface of the core material. Above all, considering the impact resistance of the obtained fiber composite, it is preferable to laminate fiber reinforced plastic layer forming materials on both sides of the core material.

Since the core material of the fiber composite of the present embodiment is compressed, it is necessary to adjust the thickness. The thickness can be adjusted by adjusting the degree of pressure applied to the laminate. For example, as a method of adjusting the compression deformation rate of the core material, a method of sandwiching the laminated body by pressing members in the thickness direction thereof and adjusting the pressing force applied to the laminated body by these pressing members is used. At this time, it is preferable to arrange spacers on the outside of the laminated body, for example, on the outer sides of both ends in the width direction or the length direction of the laminated body. By adjusting the height of the spacer, it is possible to easily adjust the degree of pressure applied to the laminate and the compression deformation rate of the foam.

When a spacer is used, the spacer may be arranged outside the laminated body, for example, at least outside both ends in the width direction or the length direction of the laminated body, and both ends in the width direction of the laminated body. Spacers may be arranged on both the outside of the portion and the outside of both ends in the length direction.

Further, by using a mold having a vacuum mold cavity structure in consideration of a constant volume and thickness, a fiber composite having a desired thickness can be obtained.

As described above, by heating and compressing the laminate in the compression step, a fiber composite is obtained which is laminated and integrated on at least one surface of the core material and has a skin material containing fibers and resins. Be done.

By cutting the core material contained in the fiber complex at the central portion in the thickness direction after performing the compression step as described above, the skin material is laminated and integrated only on one surface of the core material. Fiber composites can also be obtained.

The thickness of the fiber composite of the present embodiment is not particularly limited, but is preferably 0.5 mm to 500 mm. The thickness is determined by the thickness of the skin material and the foam that is the core material, but if the desired thickness cannot be obtained when the skin material and the core material are integrally molded under pressure, the thickness of the core material is used. By adjusting, it is possible to obtain a desired thickness.

The bending strength of the fiber composite of the present embodiment at 23 ° C. is preferably 110 to 140 MPa. The bending strength at 100 ° C. is preferably 80 to 120 MPa, more preferably 90 to 120 MPa. The difference between the bending strength at 23 ° C. and the bending strength at 100 ° C. is preferably 40 MPa or less.
The bending strength at 23 ° C. and the bending strength at 100 ° C. can be measured by the methods described in Examples described later.

In the fiber composite of the present embodiment, since the core material containing the foamed resin has the above-mentioned core layer and surface layer, the impact resistance is improved while maintaining the rigidity of the skin material in a high temperature environment. Has been done. Therefore, such a fiber composite is not particularly limited, but is suitably used as a housing for constituent members such as aircraft, automobiles, ships, and buildings, and electronic devices.

Hereinafter, the present invention will be described with reference to Examples and Comparative Examples, but the present invention is not limited thereto.

The method for measuring the physical properties of the core material before laminating is shown below.
(A) Density The weight W (kg) of the obtained core material was measured, and then the apparent volume Va (m ³ ) of the core material was measured by a submersion method. Then, the value W / Va (kg / m ³ ) obtained by dividing the weight W by the apparent volume Va was used as the density of the core material before laminating.

(B) Closed cell ratio The true volume (Vx) of the core material whose apparent volume Va was measured in (A) above was measured using an air comparative hydrometer (manufactured by Beckman Co., Ltd.). Then, the closed cell ratio S (%) was calculated according to the formula (3).
S (%) = {(Vx-W / ρ) / (Va-W / ρ)} x 100 ... (3)
In the formula, Vx is the true volume of the core material (cm ³ ), Va is the apparent volume of the core material (cm ³ ), W is the weight of the core material (g), and ρ is the weight of the core material. , The density of the base resin of the core material (g / cm ³ ).

(C) Fusion rate Use a cutter knife to make a 5 mm deep cut line on the surface of a plate-shaped core material with a length of 300 mm, a width of 300 mm, and a thickness of 20 mm. The core material was divided along this line. Regarding the pre-foamed particles appearing on the split surface, the number (a) of the pre-foamed particles broken in the particles (the pre-foamed particles are broken by the split surface) and along the interface between the pre-foamed particles. The number (b) of those broken (the interface between the pre-foamed particles is a dividing surface) is measured, and the fusion rate (%) of the core material before lamination is calculated according to the following formula (4). bottom.
Fusion rate (%) = {a / (a + b)} × 100 ... (4)

(D) Heat Fusion Temperature The pre-foamed particles of the obtained foamed resin were placed in a state where the pressure inside the bubbles was atmospheric pressure and did not contain a foaming agent such as a hydrocarbon. 10 g of the pre-foamed particles were placed in a metal mesh container so that the pre-foamed particles were in contact with each other, and then heated with saturated steam at a predetermined temperature for 30 seconds. Then, the lowest temperature (° C.) among the temperatures at which the prefoamed particles were fused by 80% or more as a whole after heating was defined as the heat fusion temperature (° C.) of the prefoamed particles.

The evaluation methods (1) to (6) of the fiber complex obtained in Examples and Comparative Examples described later will be described below.

(1) The width of the resin portion (A), the width of the resin portion (B), and the average major axis of the bubbles (C) The fiber composite is cut in the thickness direction, and the cut surface is multiplied by 100 using a scanning electron microscope. Taken at. The samples were measured while shifting from the upper skin material to the lower skin material, and bonded together to form one image. On the obtained cut surface, the distance between the outer circumferences of the bubbles was measured, and the presence or absence of the resin portion (A) and the resin portion (B) was observed. Further, in the obtained photographed image of the cut surface, 30 resin portions (A) on the core material were randomly selected, the widths thereof were measured, and the average of the resin portions (A) was measured from the arithmetic mean value. The width was set.
Next, 30 resin portions (B) were similarly randomly selected, the widths thereof were measured, and the average width of the resin portions (B) was taken from the arithmetic mean value.
Next, 30 bubbles (C) in the core material were also randomly selected, and any two points having the maximum mutual distance on the outer contour line of the bubble cross section were selected, and the distance between these two points was ". The major axis of the bubble was measured, and the average major axis of the bubble (C) was taken from the additive average value.
When bubbles having an exposed cross section were present on the surface of the core material on the cut surface, such bubbles were excluded from the measurement target. For example, when the unfoamed epidermis is cut and removed from the core material, there is a possibility that air bubbles having an exposed cross section are present on the surface of the core material.
In addition, it is confirmed by looking at the photographed image whether the resin portion (A) is continuously connected in the thickness direction from the upper skin material side to the lower skin material side, and if it is connected, "○" is displayed. , The case where they were not connected was marked as "x".
Further, it is confirmed by similarly looking at the photographed image whether the resin portion (B) and the bubble (C) are surrounded by the resin portion (A). Was set to "x".
The upper side indicates the upper surface when the horizontally placed sample is installed in the vertical press machine when integrated with the skin material, and the lower side indicates the lower surface.
The results are shown in Table 1.

(2) Apparent density of core material The core material of the fiber composite obtained in Examples and Comparative Examples was cut out in a cubic shape, the weight W (kg) was measured, and then the three sides of the core material were measured with a caliper. , Its volume V (m ³ ) was calculated. Then, the ratio of the weight W to the volume V (W / V) (kg / m ³ ) was taken as the apparent density.
The results are shown in Table 1.

(3) Bending strength The bending strength (MPa) of the fiber composites obtained in Examples and Comparative Examples was determined in accordance with JIS K7221. Specifically, 10 test pieces were cut out from the obtained sample in a size of 100 mm in length × 15 mm in width × thickness (the thickness of the obtained sample). As a standard state, five test pieces that were allowed to stand in a room controlled at a temperature of 23 ° C. and a relative humidity of 50% for 24 hours to adjust the state were provided for measurement with AUTOGRAPH AG-5000D (manufactured by Shimadzu Corporation) and specified in JIS. The bending strength (in an atmosphere of 23 ° C.) (MPa) was calculated from the formula to be calculated, and the average was calculated. In addition, as a standard state, a test piece which was allowed to stand in a room controlled at a temperature of 23 ° C. and a relative humidity of 50% for 24 hours and then left at 100 ° C. for 1 hour in a constant temperature bath to adjust the state was placed at 100 ° C. Five of them were used for measurement with AUTOGRAPH AG-5000D (manufactured by Shimadzu Corporation) in a constant temperature bath, and the bending strength (under 100 ° C. atmosphere) (MPa) was calculated from the formula specified in JIS, and the average was calculated.
The results are shown in Table 1.

(4) Appearance The surfaces of the fiber complexes obtained in Examples and Comparative Examples were visually observed, and the state of the surface layer was evaluated as follows.
The results are shown in Table 1.
◎ (excellent): The resin of the skin material is sufficiently cured, and there is no resin shortage or unevenness on the surface of the fiber composite.
○ (Good): The resin of the skin material is sufficiently cured, but some unevenness and distortion are seen on the surface of the fiber composite. × (Bad): The resin of the skin material enters the core material side and the fiber composite Fibers are exposed and uneven shapes are formed on the surface of the surface due to lack of resin. The foamed resin shrinks, causing uneven shape and distortion on the surface.

(5) Thickness The thickness (mm) of the fiber complex obtained in Examples and Comparative Examples was measured using a caliper.
The measurement location was obtained by averaging the four points by measuring the central portion of the side with the outer peripheral portion 10 mm inside the four sides. The intersection of the diagonal lines of the seat was measured at the center of the seat.
Further, the total thickness (mm) of the skin material laminated on the upper surface layer and the skin material laminated on the lower surface layer was measured using a caliper.
The results are shown in Table 1.

(Example 1)
^{A cross prepreg having a fiber texture of 200 g / m 2} and a carbon fiber content of 60% by mass, which is composed of carbon fibers having a tensile modulus of 250 GPa and an epoxy resin having a glass transition temperature of 130 ° C. after curing. The product name "Pyrofil TR3110 381FMX" (manufactured by Mitsubishi Rayon Co., Ltd.) was prepared, and one front and one back were prepared as the skin material.
Next, a polyamide-based resin foam as a core material was prepared by the following method.
Nylon 6 as a polyamide resin (trade name: UBE nylon 1022B, manufactured by Ube Industries, Ltd.) 100 parts by mass, talc as a nucleating agent 0.8 parts by mass, hindered phenolic antioxidant (Irganox1098, manufactured by BASF) 0.3 parts by mass was melt-kneaded under heating conditions with a uniaxial extruder, then extruded into strands, water-cooled in a cold water tank, and cut to prepare a pellet-shaped base resin.
To this, carbon dioxide gas as a foaming agent was contained in the base resin according to the method described in Examples of Japanese Patent Application Laid-Open No. 2011-105879. Then, by heating the base resin containing carbon dioxide gas, foaming was generated to obtain pre-foamed particles having ^{a density of 300 kg / m 3.}
By encapsulating the obtained prefoamed particles in an autoclave, compressed air was introduced over 1 hour until the pressure in the autoclave reached 0.5 MPa, and then the pressure was maintained at 0.5 MPa for 24 hours. The prefoamed particles were pressure treated.
The pre-foamed particles subjected to the pressure treatment were attached to the in-mold foam molding machine (the cavity dimensions of the in-mold molding mold are: length: 300 mm, width: 300 mm, height: 10 mm). After that, the prefoamed particles are filled, and then saturated water vapor at 135 ° C. is supplied into the cavity for 10 seconds (first stage heating), and further, saturated water vapor at 144 ° C. is supplied into the cavity for 30 seconds (2). ^{A foam having a density of 200 kg / m 3} using the pre-foamed particles was formed by foaming the pre-foamed particles and heat-sealing them.
The obtained molded product was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out a polyamide resin foam as a core material.
Using the obtained foam as a core material, one skin material is laminated on each of the upper and lower sides of the core material, and a perforated film and a breather cloth are laminated on both sides of the core material. Put the laminate in a vacuum pack with a tube that can be connected to a vacuum pump to reduce the pressure inside the vacuum pack, seal it, and seal the vacuum pack with a gauge pressure of -0.07 MPa. Continue to reduce the pressure. Next, this was placed in an autoclave for a composite material heat curing test (small autoclave DANDELION manufactured by Hanyuda Iron Works), and the temperature in the autoclave was held at 90 ° C. and a pressure of 0.3 MPa for 6 hours.
The fiber composite obtained in Example 1 is a fiber composite in which a skin material is laminated on both sides of a surface layer of a core material having a size of 300 × 300 mm. The obtained sample was cut with a cut-and-sew, the cross section was observed, a strip was made, and the bending strength was measured. The fiber complex had a good flexural modulus and a good appearance in both the standard state and the high temperature environment of 100 ° C.
Details of Example 1 are shown in Table 1.

(Example 2)
A fiber composite was obtained under the same conditions as in Example 1 except that the temperature in the autoclave for the composite material heat curing test was held at 140 ° C. and a pressure of 0.3 MPa for 1.5 hours with respect to Example 1.
Cross-section observation and bending strength were measured in the same manner as in Example 1. In addition, the obtained fiber composite had a good flexural modulus and had a good appearance in both the standard state and the high temperature environment of 100 ° C. Details of Example 2 are shown in Table 1.

(Example 3)
After obtaining the pre-foamed particles having a density of 200 kg / m ^{3 in} the same manner as in Example 2, the obtained pre-foamed particles are sealed in the autoclave, and 1 compressed air is added until the pressure in the autoclave becomes 0.5 MPa. It is introduced over a long period of time, and then a pressure treatment of holding the pressure at 0.5 MPa for 24 hours is carried out, and then, by heating at 230 ° C., further foaming is generated, and the density: 120 kg / m. A foam and a fiber composite were obtained in the same manner as in Example 2 except that the foam of ^{3 was obtained.} Details of Example 3 are shown in Table 1.

(Example 4)
The production and evaluation were carried out in the same manner as in Example 1 except that the polyamide-based resin foam as the core material was prepared by the following method.
100 parts by mass of nylon 666 (nylon 66/6) (trade name: Novamid 2430A, manufactured by DSM Co., Ltd.) as a polyamide resin, 0.8 parts by mass of talc as a nucleating agent, hindered phenol-based antioxidant (Irganox1098,) 0.3 parts by mass (manufactured by BASF) was melt-kneaded under heating conditions with an extruder, then extruded into a strand shape, water-cooled in a cold water tank, and cut to prepare a pellet-shaped base resin.
To this, carbon dioxide gas as a foaming agent was contained in the base resin according to the method described in Examples of Japanese Patent Application Laid-Open No. 2011-105879. Then, by heating the base resin containing carbon dioxide gas, foaming was generated to obtain pre-foamed particles having ^{a density of 200 kg / m 3.}
By encapsulating the obtained prefoamed particles in an autoclave, compressed air was introduced over 1 hour until the pressure in the autoclave reached 0.4 MPa, and then the pressure was maintained at 0.4 MPa for 24 hours. The prefoamed particles were pressure treated.
The pre-foamed particles subjected to the pressure treatment were molded into a mold using the mold foam molding machine used in Example 1, then filled with the pre-foamed particles, and then 40 saturated water vapors at 130 ° C. were added to the cavity. ^{A foam having a density of 200 kg / m 3} using the pre-foamed particles was formed by feeding for seconds, foaming the pre-foamed particles, and heat-sealing the pre-foamed particles.
The obtained molded product was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out a polyamide resin foam as a core material.
Using the obtained foam as a core material, the conditions were the same as in Example 1 except that the temperature in the autoclave for the heat curing test of the composite material was held at 130 ° C. and a pressure of 0.3 MPa for 3 hours. A fiber composite was obtained. This fiber complex had a good flexural modulus and a good appearance in both the standard state and the high temperature environment of 100 ° C.
Details of Example 4 are shown in Table 1.

(Example 5)
Polyphenylene ether resin (PPE) (manufactured by Asahi Kasei Co., Ltd., S201A) is 60% by mass, non-halogen flame retardant (bisphenol A-bis (diphenyl phosphate) (BBP)) is 18% by mass, and rubber concentration is 6% by mass. Impact-resistant polystyrene resin (HIPS) is 10% by mass (rubber component content in the base resin is 0.6% by mass), general-purpose polystyrene resin (PS) (PS Japan Co., Ltd., GP685) is 12% by mass, Using 0.8 parts by mass of talc as a nucleating agent and 0.3 parts by mass of a hindered phenol-based antioxidant (Irganox1098, manufactured by BASF), these are extruded after heating, melting and kneading with an extruder to serve as a base material as a core material. Resin pellets were prepared. According to the method described in Example 1 of JP-A-4-372630, the base resin pellets are housed in a pressure-resistant container, the gas in the container is replaced with dry air, and then carbon dioxide gas (gas) is used as a foaming agent. The injection was carried out, and the base resin pellets were impregnated with 7% by mass of carbon dioxide gas over 3 hours under the conditions of a pressure of 3.2 MPa and a temperature of 11 ° C.
Then, the base resin pellets were foamed with pressurized steam while rotating the stirring blades at 77 rpm in the pre-foaming machine to obtain pre-foamed particles.
The prefoamed particles were pressurized to 0.5 MPa over 1 hour, then held at 0.5 MPa for 8 hours and subjected to pressure treatment.
The pressure-treated prefoamed particles were filled in the cavity of the in-mold molding die (cavity dimensions: length: 300 mm, width: 300 mm, height: 10 mm), and then the mold was compacted. Then, this mold was attached to the in-mold foam molding machine.
Then, saturated steam at 125 ° C. is supplied into the cavity for 10 seconds (first stage heating), and then saturated water vapor at 130 ° C. is supplied into the cavity for 30 seconds (second stage heating) to prepare the pre-foamed particles. Pre-foamed particles were formed by foaming and heat-sealing.
The obtained molded product was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out a polyphenylene ether-based resin foam as a core material.
Using the obtained foam as a core material, the conditions were the same as in Example 1 except that the temperature in the autoclave for the heat curing test of the composite material was held at 80 ° C. and a pressure of 0.3 MPa for 6 hours. A fiber composite was obtained.
The fiber composite obtained in Example 5 is a fiber composite in which a skin material is laminated on the entire surface layer of the core material. Details of Example 5 are shown in Table 1.

(Example 6)
Methyl methacrylate (MMA) 70 parts by mass, styrene (ST) 10 parts by mass, maleic anhydride (MAH) 20 parts by mass, talc 0.8 parts by mass, hindered phenolic antioxidant (Irganox1098, manufactured by BASF) 0. After stirring 3 parts by mass, 0.3 part by mass of lauroyl peroxide as an initiator, and 10 parts by mass of nbutanol as a foaming agent at room temperature for 10 minutes, a flat surface of a glass plate having a length and width of 500 mm and a thickness of 10 mm was formed. Place a 15 mm silicone rubber O-packing near the edge of the glass plate, fill the O-packing with the previous monomer solution, and then place another same glass plate on it to apply the O-packing and the monomer solution. The clips were evenly tightened to a thickness of 12 mm using a plurality of clips whose thickness could be adjusted around the glass so as to be sandwiched between the glasses. It was immersed in a warm water bath at 60 ° C. for 24 hours. After that, it was taken out and cured in an oven at 130 ° C. for 1 hour, then cooled to room temperature, the clip and the glass plate were removed, and the O-packing was cut and deleted to obtain a special acrylic resin plate. This special acrylic resin was pulverized with a pulverizer and classified to obtain 2 mm pulverized particles. The crushed fine particles were placed in an explosion-proof oven at 150 ° C. for 60 minutes to cause foaming and taken out to obtain pre-foamed particles having ^{a density of 200 kg / m 3.}
By encapsulating the obtained prefoamed particles in an autoclave, compressed air was introduced over 1 hour until the pressure in the autoclave reached 0.5 MPa, and then the pressure was maintained at 0.5 MPa for 24 hours. The prefoamed particles were pressure treated.
The pressure-treated prefoamed particles were filled in the cavity of the in-mold molding die (cavity dimensions: length: 300 mm, width: 300 mm, height: 10 mm), and then the mold was compacted. Then, this mold was attached to the in-mold foam molding machine.
Then, saturated steam at 110 ° C. is supplied into the cavity for 10 seconds (first stage heating), and then saturated water vapor at 120 ° C. is supplied into the cavity for 30 seconds (heating in the second stage) to prepare the pre-foamed particles. Pre-foamed particles were formed by foaming and heat-sealing.
The obtained molded product was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out an acrylic resin foam as a core material.
Using the obtained foam as a core material, the conditions were the same as in Example 1 except that the temperature in the autoclave for the heat curing test of the composite material was held at 110 ° C. and a pressure of 0.3 MPa for 4 hours. Obtained a fiber composite in.
The fiber composite obtained in Example 6 is a fiber composite in which a skin material is laminated on the entire surface layer of the core material. Details of Example 6 are shown in Table 1.

(Example 7)
100 parts by mass of polyethylene terephthalate (PET, trade name "SA-135" manufactured by Mitsui Chemicals, Inc.), master batch made of polyethylene terephthalate containing talc (polyethylene terephthalate content: 60% by mass, talc content: 40% by mass) A polyethylene terephthalate composition containing 1.8 parts by mass, 0.2 parts by mass of pyromellitic anhydride, and 0.3 parts by mass of a hindered phenol-based antioxidant (Irganox1098, manufactured by BASF) was prepared by a single-screw extruder at 290 ° C. Melt-kneading is performed under heating conditions, and then normal butane is press-fitted into the molten polyethylene terephthalate composition so that the amount of normal butane is 0.8 parts by mass with respect to 100 parts by mass of polyethylene terephthalate from the middle of the extruder. It was evenly dispersed in terephthalate.
After that, at the front end of the extruder, the molten polyethylene terephthalate composition is cooled to 280 ° C., melt-kneaded under heating conditions with a single-screw extruder, extruded into strands, and water-cooled in a cold water tank. , Cutting was performed to obtain preliminary foamed particles having a pellet-shaped density of 400 kg / m ^3.
By encapsulating the obtained prefoamed particles in an autoclave, compressed air was introduced over 1 hour until the pressure in the autoclave reached 0.5 MPa, and then the pressure was maintained at 0.5 MPa for 24 hours. The prefoamed particles were pressure treated.
The pressure-treated prefoamed particles were filled in the cavity of the in-mold molding die (cavity dimensions: length: 300 mm, width: 300 mm, height: 10 mmt), and then the mold was compacted. Then, this mold was attached to the in-mold foam molding machine.
Then, 120 ° C. saturated steam is supplied into the cavity for 10 seconds (first stage heating), and then 130 ° C. saturated water vapor is supplied into the cavity for 30 seconds (second stage heating) to prepare the pre-foamed particles. Pre-foamed particles were formed by foaming and heat-sealing.
The obtained molded product was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out a PET-based resin foam as a core material.
Using the obtained foam as a core material, the conditions were the same as in Example 1 except that the temperature in the autoclave for the heat curing test of the composite material was held at 120 ° C. and a pressure of 0.3 MPa for 3 hours. A fiber composite was obtained. Details of Example 7 are shown in Table 1.

(Example 8)
As a raw material, a polycarbonate resin powder synthesized as follows was used as a raw material. After 710 parts by mass of 2,2-bis (4-hydroxyphenyl) propane (hereinafter sometimes referred to as "bisphenol A") was dissolved (bisphenol A solution), 2299 parts by mass of methylene chloride and 48.5% by mass of hydroxide were added. 112 parts by mass of an aqueous sodium solution was added, and 354 parts by mass of phosgene was blown at 15 to 25 ° C. over about 90 minutes to carry out a phosgenation reaction. After completion of phosgenation, 148 parts by mass of a methylene chloride solution of p-tet-butylphenol having a concentration of 11% by mass and 88 parts by mass of a 48.5% by mass sodium hydroxide aqueous solution were added, stirring was stopped, and the mixture was allowed to stand for 10 minutes. After 5 minutes of emulsification by stirring, the mixture was treated with a homomixer (Special Machinery Chemical Industry Co., Ltd.) at a rotation speed of 1200 rpm and a number of passes of 35 times to obtain a highly emulsified dope. The highly emulsified dope was reacted in a polymerization tank (with a stirrer) at a temperature of 35 ° C. for 3 hours under no stirring conditions to complete the polymerization. After completion of the reaction, the organic phase is separated, diluted with methylene chloride, washed with water, acidified with hydrochloric acid and washed with water, and when the conductivity of the aqueous phase becomes almost the same as that of ion-exchanged water, it is poured into a kneader filled with warm water. Methylene chloride was evaporated with stirring to obtain a polycarbonate powder. After dehydration, it was dried at 120 ° C. for 12 hours with a hot air circulation type dryer to obtain a polycarbonate resin powder.
High molecular weight acrylic resin (manufactured by Mitsubishi Rayon Co., Ltd., trade name "Metabrene P-530A", weight average molecular weight 3 million) with respect to 100 parts by mass of the polycarbonate resin powder (glass transition temperature 154 ° C.) thus obtained 1 Single-screw extruder using a polycarbonate resin composition containing 0.1 parts by mass and 0.1 parts by mass of a bubble conditioner (polytetrafluoroethylene powder) and 0.3 parts by mass of a hindered phenol-based antioxidant (Irganox1098, manufactured by BASF). After melt-kneading under heating conditions of 300 ° C., the resin was extruded into a strand shape, water-cooled in a cold water tank, and cut to prepare a pellet-shaped base resin.
The obtained base resin is housed in a pressure-resistant container, the gas in the container is replaced with dry air, carbon dioxide gas (gas) is injected as a foaming agent, and the pressure is 3.0 MPa and the temperature is 11 ° C. Over time, the base resin pellets were impregnated with 7.5% by mass of carbon dioxide. Then, the base resin containing carbon dioxide gas was heated with heated steam to cause foaming, and pre-foamed particles having ^{a density of 200 kg / m 3 were obtained.} Then, saturated steam at 125 ° C. is supplied into the cavity for 10 seconds (first stage heating), and then saturated water vapor at 130 ° C. is supplied into the cavity for 30 seconds (second stage heating) to prepare the pre-foamed particles. Pre-foamed particles were formed by foaming and heat-sealing.
The obtained molded product was cooled by supplying cooling water into the cavity of the mold, and then the mold was opened to take out a polycarbonate resin foam as a core material.
Using the obtained foam as a core material, the conditions were the same as in Example 1 except that the temperature in the autoclave for the heat curing test of the composite material was held at 120 ° C. and a pressure of 0.3 MPa for 3 hours. A fiber composite was obtained. Details of Example 8 are shown in Table 1.

(Comparative Example 1)
In the polycarbonate resin composition used in Example 8, the temperature of a 50 mmφT die biaxial extruder having an L / D of 40 was set to 280 ° C., the raw material was charged from the hopper, and liquefied normal butane was added at a pressure of 1 MPa in the middle of the barrel. By pressure injection, the polycarbonate resin was foamed at the outlet of the T die, and normal butane was vaporized. From the outlet, a foamed resin having come out from above and below with a stainless seam belt was sandwiched to obtain a foamed sheet having a thickness of 10 mm and a width of 400 mm. The thickness was 10 mm by adjusting the lip gap of the T-die and the gap between the upper and lower stainless seam belts. As for the width, a width of 400 mm was obtained by using a T-die having a mouth width of 400 mm.
A foam obtained by cutting out 300 × 300 × 10 mm from the obtained foam sheet was used as a core material, and the obtained foam was used as a core material. A fiber composite was obtained under the same conditions as in Example 1 except that the mixture was held at 120 ° C. and a pressure of 0.3 MPa for 3 hours. Details of Comparative Example 1 are shown in Table 1.

(Comparative Example 2)
The prefoamed particles having a density of 200 kg / m ³ obtained in Example 8 were used and attached to an in-mold foam molding machine (the cavity dimensions of the in-mold molding mold were: length: 300 mm, width: 300 mm, After molding the mold (height: 10 mm), pre-foamed particles are filled, and then saturated steam at 125 ° C. is supplied into the cavity for 20 seconds to foam the pre-foamed particles and heat-fuse them. By doing so, the foam was molded.
Using the obtained foam as a core material, the fiber composite was prepared under the same conditions as in Example 1 except that the temperature in the autoclave was held at 80 ° C. and a pressure of 0.3 MPa for 0.5 hours. Obtained. Details of Comparative Example 2 are shown in Table 1.

In Examples 1 to 8, the bending strength in the atmosphere of 23 ° C. and 100 ° C. was high, and the appearance and the thickness of the fiber complex were uniform, which was a good result. On the other hand, in Comparative Example 1, the thickness of the resin portion (A) is almost the same as that of the resin portion (B) and is thin, so that it is judged that there is no resin portion (A). Therefore, the resin portion (A) is not connected, the resin portion (B) and the bubbles (C) are not surrounded by the resin portion (A), and the bending strength in an atmosphere of 100 ° C. is low. .. In addition, the thickness of the center of the fiber complex was thick, and the surface was distorted like a drum, which was not good. In Comparative Example 2, it is determined that the resin portion (A) is thin due to insufficient time during heat welding of the foamed particles and autoclave molding, and therefore there is no resin portion (A). In addition, the resin portion (A) was not connected in many places, resulting in low bending strength in an atmosphere of 100 ° C. In addition, the thickness of the center of the fiber complex was thin, and the surface was distorted, which was not good.

The fiber composite of the present embodiment is excellent in excellent rigidity and aesthetic appearance in a high temperature environment such as 100 ° C., and excellent surface cosmeticity at the time of high temperature molding. The fiber composite of the present invention can be suitably used particularly in the field of automobiles.

1 Fiber composite 2 Core material 3 Skin material 4 Resin part (A)
5 Resin part (B)
6 Bubbles (C)

Claims (3)

A fiber complex containing a core material containing a foamed resin and having a skin material containing fibers and a resin laminated on at least a part of the surface of the core material.
Wherein in the thickness direction of the cross section of the fiber composite, the width 8μm or more resin portion in the core material (A), and average major axis is viewed contains air bubbles (C) of 5～800Myuemu,
In the cross section, at least a part of the resin portion (A) is continuously connected from one surface of the core material to the other surface.
In the cross section, the structure in which the plurality of bubbles (C) are surrounded by the resin portion (A) is included.
A fiber composite characterized in that the foamed resin is a polyamide-based resin. The fiber composite according to claim 1, wherein the resin portion (A) has a continuous point where the width of the resin portion is 8 μm or more and continues for 1 mm or more. The fiber composite according to claim 1 or 2, wherein the resin portion (A) has an average width of 8 to 40 μm.

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