JP7301289B2 - Molded product manufacturing method - Google Patents

Description

The present invention relates to a method for manufacturing molded articles. In particular, the present invention relates to a method of manufacturing a molded product having standing portions such as ribs.

In recent years, attention has been paid to fiber-reinforced thermoplastic (FRP) materials composed of reinforcing fibers and thermoplastic resin. FRP is widely used in various applications due to its light weight and high strength.
On the other hand, it is being studied to manufacture a molded product having standing portions such as ribs using the FRP as described above.
For example, Patent Document 1 discloses a method for manufacturing a molded product having a first portion and a second portion erected from the first portion, wherein reinforcing fibers (A) having a length of more than 30 mm and A first material containing a thermoplastic resin (B), wherein the reinforcing fibers (A) are dispersed in the first material, and the thermoplastic resin (B) is the reinforcing fibers ( A) a second material containing a reinforcing fiber (a) having a length of 1 to 30 mm and a thermoplastic resin (b) on the surface of the first material that is not substantially impregnated with the reinforcing fiber ( a) is dispersed in a second material, and the thermoplastic resin (b) is not substantially impregnated into the reinforcing fibers (a); A molded product comprising simultaneously molding a first part and a second part by press working of, wherein the adhesion strength between the thermoplastic resin (B) and the thermoplastic resin (b) is 2 N / 15 mm or more. is disclosed.

WO2016/167136

Although the method described in Patent Literature 1 is an excellent method, as the demand for FRP expands, there is a demand for a new method of manufacturing a molded product having standing portions such as ribs. In particular, when a layer in which reinforcing fibers such as nonwoven fabric and thermoplastic resin fibers are randomly dispersed is used as a base material, and a shape-retaining material of mixed yarns is used to form standing portions such as ribs on the base material. However, it has been found that the strength of the standing portion of the resulting molded product may be inferior. A method for producing a molded product using a material in which a randomly dispersed layer is used as a base material and a shape-retaining mixed yarn is used, wherein the obtained molded product has a high strength in the standing portion. intended to provide

Under such circumstances, the present inventor conducted studies and found that the above problems can be solved by adjusting the heating temperature of the material during molding. Specifically, the above problems have been solved by the following means.
<1> A mixed fiber yarn composed of a layer in which reinforcing fibers (A1) and thermoplastic resin fibers (B1) are randomly dispersed, and continuous reinforcing fibers (A2) and thermoplastic resin fibers (B2) In a state in which the mixed yarn is arranged on the layer, the mixed yarn is shape-retained by the thermoplastic resin fibers (B3), the material is placed on the layer side and heating the thermoplastic resin fibers (B3) at a temperature not higher than the melting point of the thermoplastic resin fibers (B3), and forming the thermoplastic resin fibers (B3) from the side where the mixed yarn is shaped By heating at a temperature above the melting point of the thermoplastic resin (b3), more than 99% by mass of the thermoplastic resin fiber (B1), more than 99% by mass of the thermoplastic resin fiber (B2), and the heat More than 50% by mass and 90% by mass or less of the portion of the plastic resin fiber (B3) exposed on the mixed yarn side, and 1% by mass of the portion of the thermoplastic resin fiber (B3) exposed to the layer side A method for producing a molded product having an erected portion, comprising melting more than 50% by mass or less and molding in the molten state.
<2> The method for producing a molded article according to <1>, wherein the layer has a density of 0.06 to 0.9 mg/mm ³ .
<3> The method for producing a molded article according to <1> or <2>, wherein the layer has a puncture strength of 0.08 to 0.9N.
<4> The melting point of the thermoplastic resin (b3) constituting the thermoplastic resin fiber (B3) is higher than the melting point of the thermoplastic resin (b2) constituting the thermoplastic resin fiber (B2), and the heat The method for producing a molded article according to any one of <1> to <3>, wherein the melting point of the thermoplastic resin (b1) constituting the plastic resin fiber (B1) is higher than that of the thermoplastic resin (b1).
<5> The difference between the melting point of the thermoplastic resin (b2) constituting the thermoplastic resin fiber (B2) and the melting point of the thermoplastic resin (b1) constituting the thermoplastic resin fiber (B1) is 2 to 70. ° C., the method for producing a molded article according to any one of <1> to <4>.
<6> The method for producing a molded article according to any one of <1> to <5>, wherein the layer is a nonwoven fabric.
<7> Any one of <1> to <6>, wherein the impregnation rate of the thermoplastic resin fibers (B1) into the reinforcing fibers (A1) in the layer is 0.1% or more and 30% or less. manufacturing method of the molding.
<8> The method for producing a molded article according to any one of <1> to <7>, wherein the layer contains at least one selected from carbon fibers and glass fibers as reinforcing fibers (A1).
<9> The molding according to any one of <1> to <8>, wherein the layer contains at least one thermoplastic resin selected from polyamide resins and polyolefin resins as the thermoplastic resin (b1). method of manufacturing the product.
<10> The layer comprises, as the thermoplastic resin (b1), structural units derived from a diamine and structural units derived from a dicarboxylic acid, and 50 mol% or more of the structural units derived from the diamine are derived from xylylenediamine. The method for producing a molded article according to any one of <1> to <9>, including a polyamide resin that
<11> The molded article according to any one of <1> to <10>, wherein the mixed yarn contains at least one selected from carbon fibers and glass fibers as continuous reinforcing fibers (A2). Production method.
<12> Any one of <1> to <11>, wherein the mixed yarn contains, as the thermoplastic resin (b2), at least one thermoplastic resin selected from polyamide resins and polyolefin resins. manufacturing method of the molding.
<13> The mixed yarn comprises, as the thermoplastic resin (b2), a diamine-derived structural unit and a dicarboxylic acid-derived structural unit, and 50 mol% or more of the diamine-derived structural units is xylylenediamine. The method for producing a molded article according to any one of <1> to <12>, comprising a polyamide resin derived from.

According to the present invention, there is provided a method for manufacturing a molded article using a material in which a layer in which reinforcing fibers and thermoplastic resin fibers are randomly dispersed is used as a base material and a shape-retaining mixed yarn is used. It has become possible to provide a method for manufacturing a molded product having a high-strength standing portion.

It is a schematic diagram which shows the material used by this invention. It is a schematic diagram which shows an example of the process of press working in this invention. FIG. 3 is an enlarged view of a circled portion indicated by a dotted line in FIG. 2; FIG. 5 is a schematic diagram showing another example of the press working process in the present invention. It is an example of the image which observed the cross section of the mixed yarn with the microscope. It is a top surface schematic diagram of the metal mold|die used in an Example. It is a figure which shows the cross-sectional shape of the erection site|part of the metal mold|die used in an Example. It is a schematic diagram showing a method for measuring the strength of a molded product in Examples.

The contents of the present invention will be described in detail below. In this specification, the term "~" is used to mean that the numerical values before and after it are included as the lower limit and the upper limit.
In this specification, various physical property values and characteristic values are at 23° C. unless otherwise specified.

The method for producing a molded article having standing portions of the present invention includes a layer in which reinforcing fibers (A1) and thermoplastic resin fibers (B1) are randomly dispersed, continuous reinforcing fibers (A2) and thermoplastic resin fibers (B2), wherein the shape of the mixed yarn is retained by the thermoplastic resin fibers (B3) in a state in which the mixed yarn is arranged on the layer. heating the material from the layer side at a temperature equal to or lower than the melting point of the thermoplastic resin fibers (B3); , By heating at a temperature above the melting point of the thermoplastic resin (b3) constituting the thermoplastic resin fiber (B3), more than 99% by mass of the thermoplastic resin fiber (B1) and the thermoplastic resin fiber More than 99% by mass of (B2), more than 50% by mass to 90% by mass of the portion of the thermoplastic resin fiber (B3) exposed on the side on which the mixed yarn is arranged, and the thermoplastic resin fiber (B3) and melting more than 1% by mass and 50% by mass or less of the portion exposed to the layer side, and molding in the melted state.
In this way, on the side of the layer in which the reinforcing fibers (A1) and the thermoplastic resin fibers (B1) are randomly dispersed (hereinafter sometimes referred to as "layer of nonwoven fabric etc."), By melting the thermoplastic resin fiber (B1) and the thermoplastic resin fiber (B2) contained in the mixed yarn, the adhesion between the layer of nonwoven fabric and the mixed yarn can be enhanced. On the other hand, on the mixed yarn side, by moderately melting the thermoplastic resin fibers (B3) that retain the shape of the mixed yarn, the arrangement of the continuous reinforcing fibers (A2) in the mixed yarn is maintained while standing upright. Intrusion of material into the installation site can be made easier. As a result, it is presumed that both the mixed filament yarn and the layer of the nonwoven fabric can be inserted into the erected portion, and a molded product having excellent strength in the erected portion can be obtained.
BEST MODE FOR CARRYING OUT THE INVENTION The present invention will be described in detail below.

[material]
The materials used in the present invention include a layer (layer such as nonwoven fabric) in which reinforcing fibers (A1) and thermoplastic resin fibers (B1) are randomly dispersed, continuous reinforcing fibers (A2) and continuous thermoplastic resin fibers ( B2) and mixed yarns. Furthermore, it contains a thermoplastic resin fiber (B3) that retains the shape of the mixed yarn in a layer such as a nonwoven fabric.
FIG. 1 is a schematic diagram showing the materials used in the present invention. 1 is a layer of nonwoven fabric or the like, 2 is a mixed yarn, and 3 is a thermoplastic resin fiber that holds the shape of the mixed yarn in the layer of the nonwoven fabric or the like. (B3) is shown. (a) is a plane direction of a layer of a non-woven fabric or the like, viewed from the side on which mixed yarns are provided, and (b) is a view viewed from the cross-sectional direction of (a). By using such a material, the continuous reinforcing fibers (A2) contained in the mixed yarn can be molded without deviation in orientation, and the strength of the standing portion can be increased. That is, the mixed yarn is provided on a layer of nonwoven fabric or the like (preferably on the surface), depending on the shape of the desired molded product, preferably at a position corresponding to the standing portion. By molding while maintaining the orientation of the continuous reinforcing fibers (A2), a molded product (particularly, the standing portion) having excellent strength can be obtained.

<layer>
In the present invention, a layer (layer of nonwoven fabric or the like) in which reinforcing fibers (A1) and thermoplastic resin fibers (B1) are randomly dispersed is used. The layer is exemplified by a nonwoven fabric. The layer of nonwoven fabric or the like preferably has a flat plate shape, but may have a curved surface or have some unevenness within the scope of the present invention. In the nonwoven fabric layer used in the present invention, 90% by mass or more of the nonwoven fabric layer is preferably composed of the reinforcing fiber (A1) and the thermoplastic resin fiber (B1), and more preferably 93% by mass or more. , more preferably 95% by mass or more. The entire layer (100% by mass) of the nonwoven fabric or the like may be composed of the reinforcing fibers (A1) and the thermoplastic resin fibers (B1).
A part of the layer of the nonwoven fabric or the like has an erected portion, and the other constitutes the main body of the molded product (a portion that is not the erected portion). In addition, in the molded product of the present invention, it is presumed that part of the layer such as the nonwoven fabric enters the erected portion and is molded. As a result, it is presumed that a molded article having excellent strength can be obtained. When a layer of nonwoven fabric or the like enters the standing part, the part derived from the layer such as nonwoven fabric may be relatively large on the side closer to the surface layer of the molded product, or the side farther from the surface layer of the molded product may be relatively The portion derived from a layer such as a nonwoven fabric may be large.
Only one layer of nonwoven fabric or the like may be used, or two layers or three layers or more may be used. Although there is no upper limit, 10 layers or less is desirable in view of operability.

The layer of nonwoven fabric or the like preferably has a density of 0.06 to 0.9 mg/mm ³ . By making it more than the said lower limit, there exists a tendency for the impregnating property of a molded article to be excellent. In addition, by making it equal to or less than the above upper limit, there is a tendency to obtain a molded product that is flexible and excellent in drape performance.
The density is preferably 0.07 mg/mm ³ or higher, more preferably 0.08 mg/mm ³ or higher, even more preferably 0.09 mg/mm ³ or higher. Also, the density is preferably 0.8 mg/mm ³ or less, more preferably 0.7 mg/mm ³ or less, and even more preferably 0.6 mg/mm ³ or less.
Density is measured according to the method described in the examples below.

In the present invention, the layer of the nonwoven fabric or the like preferably has a puncture strength of 0.08 to 0.9N. By making it equal to or higher than the lower limit, the shape retention of the mixed yarn can be performed more accurately. Further, when the thickness is equal to or less than the above upper limit, damage to needles for shape retention is suppressed, and continuous productivity tends to be excellent.
The puncture strength is preferably 0.10 N or more, more preferably 0.12 N or more, and even more preferably 0.15 N or more. The puncture strength is preferably 0.87N or less, more preferably 0.85N or less, and even more preferably 0.83N or less.
The puncture strength is measured according to the method described in Examples below.

In the present invention, the thickness of the layer of the nonwoven fabric or the like is preferably 0.1 to 4 mm. By making it equal to or higher than the lower limit, the shape retention of the mixed yarn can be performed more accurately. In addition, when the thickness is equal to or less than the above upper limit, damage to needles for shape retention is suppressed, and continuous productivity tends to be excellent.
The thickness is preferably 0.1 mm or more, more preferably 0.15 mm or more, even more preferably 0.2 mm or more, and may be 0.4 mm or more. The thickness is preferably 2 mm or less, more preferably 1 mm or less, and even more preferably 0.6 mm or less.
The thickness is measured according to the method described in Examples below.

In addition, the thickness of the layer of the nonwoven fabric or the like is preferably 1/2 or less of the width of the thinnest part of the opening of the mold corresponding to the standing part, and should be 1/2 to 1/4. is more preferred. By making it 1/2 or less, it becomes easier for the layer of nonwoven fabric or the like to enter the erected portion, and the strength of the resulting molded product tends to be improved.

In the present invention, it is preferable that the impregnation rate of the reinforcing fibers (A1) of the thermoplastic resin fibers (B1) is 0.1% or more and 30% or less in the layer such as the nonwoven fabric. By making it more than the said lower limit, fluffing can be suppressed more effectively. In addition, by making it equal to or less than the above upper limit, there is a tendency to obtain a molded product that is flexible and excellent in drape performance.
The impregnation rate is preferably 0.1% or more, more preferably 1% or more, and even more preferably 3% or more. The impregnation rate is preferably 25% or less, more preferably 20% or less, and even more preferably 16% or less.

As the reinforcing fiber (A1) in the layer of the nonwoven fabric or the like, a wide range of reinforcing fibers known in the technical field of the present invention can be used. Reinforcing fibers (A1) mean fibers having a higher strength (eg, elastic modulus) than thermoplastic resin fibers (B1). For example, the elastic modulus of the reinforcing fiber (A1) is 30 GPa or more.

The reinforcing fibers (A1) used in the present invention include inorganic fibers such as glass fibers, carbon fibers, alumina fibers, boron fibers, ceramic fibers, metal fibers (steel fibers, etc.), and vegetable fibers (Kenaf, bamboo fibers, etc.). etc.), cellulose fibers (including cellulose nanofibers), aramid fibers, polyoxymethylene fibers, aromatic polyamide fibers, polyparaphenylenebenzobisoxazole fibers, and organic fibers such as ultra-high molecular weight polyethylene fibers. Among them, it preferably contains at least one of carbon fiber, aramid fiber and glass fiber, more preferably contains at least one selected from carbon fiber and glass fiber, and contains at least one of carbon fiber. More preferred.
The reinforcing fibers (A1) may be recycled fibers, particularly recycled carbon fibers.

The reinforcing fibers (A1) used in a preferred embodiment of the present invention are preferably treated with a treating agent. Examples of such treatment agents include sizing agents and surface treatment agents, and those described in paragraphs 0093 and 0094 of Japanese Patent No. 4894982 are preferably employed, the contents of which are incorporated herein.

Examples of surface treatment agents include functional compounds such as epoxy-based compounds, acrylic compounds, isocyanate-based compounds, silane-based compounds, and titanate-based compounds. A ring agent or the like, preferably a silane-based coupling agent.

The sizing agent is preferably at least one of epoxy resin, urethane resin, silane compound, isocyanate compound, titanate compound and polyamide resin. It is more preferably at least one of an insoluble polyamide resin and a water-soluble polyamide resin, more preferably at least one of an epoxy resin, a urethane resin, a water-insoluble polyamide resin and a water-soluble polyamide resin, and a water-soluble polyamide resin. More preferably.

The amount of the treatment agent is preferably 0.001 to 1.5% by mass, more preferably 0.1 to 1.2% by mass, and more preferably 0.3 to 1.5% by mass of the reinforcing fiber (A1). More preferably, it is 1% by mass.

A known method can be adopted as a method for treating the reinforcing fibers (A1) with a treating agent. For example, the reinforcing fibers (A1) may be immersed in a solution in which the treating agent is dissolved to allow the treating agent to adhere to the surfaces of the reinforcing fibers (A1). Alternatively, the treating agent can be air-blown onto the surface of the reinforcing fibers (A1). Furthermore, reinforcing fibers (A1) that have already been treated with a surface treatment agent or treatment agent may be used, or after washing off the commercially available surface treatment agent or treatment agent, the desired amount of treatment agent is applied again. You may re-surface-treat so that it may become.

The number average fiber length of the reinforcing fibers (A1) in the layer such as the nonwoven fabric is preferably 10 mm or more and less than 100 mm. By making it equal to or higher than the above lower limit, the strength of the resulting molded article tends to be higher. In addition, by making it equal to or less than the above upper limit, there is a tendency that the isotropy of the molded product is more excellent.
The number average fiber length is preferably 12 mm or longer, more preferably 15 mm or longer, and even more preferably 20 mm or longer. Also, the number average fiber length is preferably 95 mm or less, more preferably 90 mm or less, and even more preferably 80 mm or less.

The content of the reinforcing fiber (A1) in the layer such as the nonwoven fabric is preferably 30 to 80% by mass of the layer such as the nonwoven fabric. By making it more than the said lower limit, there exists a tendency for it to be excellent by the strength of a molded article. In addition, when the amount is equal to or less than the above upper limit, there is a tendency that the impregnating property of the molded product is more excellent.
The content of the reinforcing fibers (A1) is preferably 30% by mass or more, more preferably 35% by mass or more, and even more preferably 40% by mass or more. Moreover, the content is preferably 80% by mass or less, more preferably 75% by mass or less, and even more preferably 70% by mass or less.

The content of the reinforcing fiber (A1) in the layer such as nonwoven fabric is preferably 17 to 75% by volume of the layer such as nonwoven fabric. By making it more than the said lower limit, there exists a tendency for it to be excellent by the strength of a molded article. In addition, when the amount is equal to or less than the above upper limit, there is a tendency that the impregnating property of the molded product is more excellent.
The content of the reinforcing fibers (A1) is preferably 17% by volume or more, more preferably 25% by volume or more, and even more preferably 30% by volume or more. The content is preferably 70% by volume or less, more preferably 65% by volume or less, and even more preferably 60% by volume or less.
Only one type of the reinforcing fiber (A1) may be used, or two or more types may be used. When two or more kinds are used, the total amount is preferably within the above range.

As the thermoplastic resin fibers (B1) in the layer of the nonwoven fabric or the like, widely known thermoplastic resin fibers can be used in the technical field of the present invention.

The thermoplastic resin fiber (B1) used in the present invention can be formed from a thermoplastic resin composition. The thermoplastic resin composition may consist of only one or two or more thermoplastic resins (b1), and may contain other components.

The thermoplastic resin (b1) includes polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyamide resins, polyethylene terephthalate and polybutylene terephthalate, polycarbonate resins, polyoxymethylene resins (polyacetal resins), polyether ketones, and polyether ethers. Polyether ketone resin such as ketone, polyether ketone ketone, polyether ether ketone ketone, polyether sulfone resin, polyether sulfide resin, polyphenylene sulfide resin, thermoplastic polyetherimide, thermoplastic polyamideimide, wholly aromatic polyimide, semi- A thermoplastic polyimide resin such as an aromatic polyimide can be used, and it preferably contains at least one thermoplastic resin selected from polyamide resins and polyolefin resins, and more preferably contains at least a polyamide resin.

Polyamide resins used in the present invention include polyamide 4, polyamide 6, polyamide 11, polyamide 12, polyamide 46, polyamide 66, polyamide 610, polyamide 612, polyhexamethylene terephthalamide (polyamide 6T), and polyhexamethylene isophthalamide. (polyamide 6I), polyamide 66/6T, polyxylylene adipamide, polyxylylene sebacamide, polyxylylene dodecamide, polyamide 9T, polyamide 9MT, polyamide 6I/6T and the like.

Among the above-mentioned polyamide resins, from the viewpoint of moldability and heat resistance, it is composed of a structural unit derived from a diamine and a structural unit derived from a dicarboxylic acid, and 50 mol% or more of the structural units derived from a diamine is xylylene Polyamide resins derived from amines (hereinafter sometimes referred to as "XD-based polyamides") are preferred.

Further, when the polyamide resin is a mixture, the ratio of the XD-based polyamide in the polyamide resin is preferably 50% by mass or more, more preferably 80% by mass or more, further preferably 90% by mass or more, particularly may be 95% by mass or more.

In the XD-based polyamide, preferably 70 mol% or more, more preferably 80 mol% or more, still more preferably 90 mol% or more, and still more preferably 95 mol% or more of diamine-derived structural units are derived from xylylenediamine. , preferably 50 mol% or more, more preferably 70 mol% or more, still more preferably 80 mol% or more, still more preferably 90 mol% or more, still more preferably 95 mol% or more of the dicarboxylic acid-derived structural units, It is derived from an α,ω-straight-chain aliphatic dicarboxylic acid having preferably 4 to 20 carbon atoms.
The xylylenediamine preferably contains at least meta-xylylenediamine, more preferably 30 to 100 mol% of meta-xylylenediamine and 70 to 0 mol% of para-xylylenediamine, and 50 to 100 mol. % meta-xylylenediamine and 50 to 0 mol % para-xylylenediamine.

Examples of diamines other than meta-xylylenediamine and para-xylylenediamine that can be used as raw material diamine components for XD-based polyamides include tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, and octamethylenediamine. Aliphatic diamines such as methylenediamine, nonamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4-trimethyl-hexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 1,3-bis(amino methyl)cyclohexane, 1,4-bis(aminomethyl)cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane , alicyclic diamines such as bis(aminomethyl)decalin and bis(aminomethyl)tricyclodecane, diamines having aromatic rings such as bis(4-aminophenyl) ether, paraphenylenediamine, bis(aminomethyl)naphthalene, etc. can be exemplified, and can be used alone or in combination of two or more.
When a diamine other than xylylenediamine is used as the diamine component, it is less than 50 mol%, preferably 30 mol% or less, more preferably 1 to 25 mol%, particularly preferably 1 to 25 mol% of the structural units derived from the diamine. It is used in a proportion of 5 to 20 mol %.

Examples of α,ω-straight-chain aliphatic dicarboxylic acids having 4 to 20 carbon atoms which are preferably used as raw dicarboxylic acid components for polyamide resins include succinic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, and adipic acid. , sebacic acid, undecanedioic acid, dodecanedioic acid, etc. can be exemplified, and one or a mixture of two or more thereof can be used. Adipic acid and/or sebacic acid are preferred, and sebacic acid is more preferred, because of the range.

Examples of dicarboxylic acid components other than the α,ω-straight-chain aliphatic dicarboxylic acids having 4 to 20 carbon atoms include phthalic acid compounds such as isophthalic acid, terephthalic acid and orthophthalic acid, 1,2-naphthalenedicarboxylic acid, 1, 3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3- Naphthalenedicarboxylic acids such as naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid can be exemplified, and can be used singly or in combination of two or more.

When a dicarboxylic acid other than the α,ω-straight-chain aliphatic dicarboxylic acid having 4 to 20 carbon atoms is used as the dicarboxylic acid component, terephthalic acid and isophthalic acid may be used from the viewpoint of moldability. When using these, the ratio of terephthalic acid and isophthalic acid is preferably 30 mol% or less, more preferably 1 to 30 mol%, particularly preferably 5 to 20 mol% of the dicarboxylic acid-derived structural units. be.

In the present specification, "composed of diamine-derived structural units and dicarboxylic acid-derived structural units" means that these components are the main components, but does not completely exclude structural units other than these. - Structural units derived from lactams such as caprolactam and laurolactam, and aliphatic aminocarboxylic acids such as aminocaproic acid and aminoundecanoic acid may be included. In the present invention, the sum of diamine-derived structural units and dicarboxylic acid-derived structural units in the polyamide resin preferably accounts for 90% by mass or more, more preferably 95% by mass or more, of all structural units.

In the first embodiment of the polyamide resin used in the present invention, 80 mol% or more of the diamine-derived structural units are derived from metaxylylenediamine, and 80 mol% or more of the dicarboxylic acid-derived structural units are derived from adipic acid. It is a mode.
In the second embodiment of the polyamide resin used in the present invention, 10 to 90 mol% of the diamine-derived structural units are derived from meta-xylylenediamine, 90 to 10 mol% are derived from para-xylylenediamine, and dicarboxylic acid In this embodiment, 80 mol % or more of the derived structural units are derived from sebacic acid.

The polyamide resin used in the present invention preferably has a number average molecular weight (Mn) of 6,000 to 30,000, more preferably 8,000 to 28,000, still more preferably 9,000 to 26, 000, more preferably 10,000 to 24,000, even more preferably 11,000 to 22,000. Within such a range, the heat resistance, elastic modulus, dimensional stability, and moldability of the resulting molded article are improved.

The number average molecular weight (Mn) referred to here is defined by the following formula from the terminal amino group concentration [NH ₂ ] (μ equivalent/g) and the terminal carboxyl group concentration [COOH] (μ equivalent/g) of the polyamide resin. Calculated.
Number average molecular weight (Mn) = 2,000,000/([COOH] + [ _NH2 ])

The method for producing a polyamide resin can be referred to paragraphs 0052 to 0053 of JP-A-2014-173196, and the contents thereof are incorporated herein.

The thermoplastic resin (b1) preferably has a melting point of 130 to 320°C. By making it more than the said lower limit, it exists in the tendency which is excellent by heat resistance. Moreover, by making it below the said upper limit, there exists a tendency for it to be excellent by molding processability.
The melting point is preferably 130° C. or higher, more preferably 140° C. or higher, and even more preferably 150° C. or higher. The melting point is preferably 315° C. or lower, more preferably 310° C. or lower, further preferably 300° C. or lower, further preferably 280° C. or lower, 270° C. or lower, or 250° C. or lower. may By setting the temperature within the above range, the amount of gas generated during molding tends to be reduced.
The melting point is measured according to the method described in the examples below.

Further, the thermoplastic resin fiber (B1) used in the present invention or the thermoplastic resin composition as a raw material thereof may contain various components within a range that does not impair the objects and effects of the present invention. For example, elastomers, fillers other than reinforcing fibers (A1), antioxidants, stabilizers such as heat stabilizers, hydrolysis resistance improvers, weather stabilizers, matting agents, UV absorbers, nucleating agents, plasticizers, Additives such as dispersants, flame retardants, antistatic agents, anti-coloring agents, anti-gelling agents, coloring agents, release agents, and lubricants can be added. Details thereof can be referred to paragraphs 0130 to 0155 of Japanese Patent No. 4894982, and the contents thereof are incorporated herein.

In the present invention, 80% by mass or more (preferably 90% by mass or more, more preferably 95% by mass or more, and still more preferably 98% by mass or more) of the thermoplastic resin fiber (B1) is the thermoplastic resin (b1). Morphology is exemplified.

The thermoplastic resin fiber (B1) in the present invention is preferably a thermoplastic resin fiber having a treating agent for thermoplastic resin fibers on its surface. These details are synonymous with the treatment agent described later for the thermoplastic resin fiber (B2), and the preferred ranges are also the same.

The number average fiber length of the thermoplastic resin fibers (B1) in the layer such as the nonwoven fabric is preferably 10 to 100 mm. By making it more than the said lower limit, it tends to be excellent by the intensity|strength of layers, such as a nonwoven fabric. The number average fiber length is preferably 12 mm or longer, more preferably 15 mm or longer, and even more preferably 20 mm or longer. Also, the number average fiber length is preferably 95 mm or less, more preferably 90 mm or less, and even more preferably 80 mm or less.
In addition, when the content is equal to or less than the above upper limit, there is a tendency that the layer of the nonwoven fabric or the like is more homogenized. In particular, when the length is approximately the same as that of the reinforcing fibers (A1) (for example, the difference between the number average fiber lengths of the two is 3 mm or less, further 1 mm or less), there is an effect of excellent layer homogeneity.

The number average fiber diameter of the thermoplastic resin fibers (B1) in the layer such as the nonwoven fabric is preferably 8 to 50 μm. By making it more than the said lower limit, it tends to be excellent by the intensity|strength of layers, such as a nonwoven fabric. Further, by making the thickness equal to or less than the above upper limit, there is a tendency that the drape performance of the layer such as nonwoven fabric is excellent.
The number average fiber diameter is preferably 9 μm or more, more preferably 10 μm or more, and even more preferably 12 μm or more. Also, the number average fiber diameter is preferably 50 μm or less, more preferably 45 μm or less, and even more preferably 40 μm or less.

The content of the thermoplastic resin fiber (B1) in the layer such as the nonwoven fabric is preferably 20 to 70% by mass of the layer such as the nonwoven fabric. When the amount is equal to or higher than the above lower limit, there is a tendency that the impregnation of the thermoplastic resin in the molded article is more excellent. In addition, when the content is equal to or less than the above upper limit, the strength of the molded product tends to be more excellent.
The content of the thermoplastic resin fibers (B1) is preferably 22% by mass or more, more preferably 25% by mass or more, and even more preferably 30% by mass or more. The content is preferably 67% by mass or less, more preferably 65% by mass or less, and even more preferably 60% by mass or less.
Only one kind of the thermoplastic resin fiber (B1) may be used, or two or more kinds thereof may be used. When two or more kinds are used, the total amount is preferably within the above range.

As a method for producing a nonwoven fabric, the descriptions in paragraphs 0023 to 0030 of JP-A-2014-224333 can be referred to, and the contents thereof are incorporated herein.

<Mixed yarn>
In the present invention, a mixed yarn composed of continuous reinforcing fibers (A2) and thermoplastic resin fibers (B2) is used. Some of the mixed yarns have standing parts, and the other part forms the main body of the molded product (the part that does not have the standing parts). In addition, it is presumed that part of the mixed filament yarn enters the erected portion of the molded product of the present invention and is molded. As a result, it is presumed that a molded article having excellent strength can be obtained. When the mixed yarn enters the erected portion, the part closer to the surface layer of the molded product may be relatively more derived from the mixed yarn, or the side farther from the surface layer of the molded product may be relatively mixed yarn. The portion derived from the thread may be large.
The continuous reinforcing fiber (A2) means a resin having a higher strength (for example, elastic modulus) than the thermoplastic resin fiber (B2).

The mixed yarn includes continuous reinforcing fibers (A2) and thermoplastic resin fibers (B2), and these fibers are arranged side by side to form a long material such as a thread or tape. The mixed yarn used in the present invention is usually preferably composed of continuous reinforcing fibers (A2) and thermoplastic resin fibers (B2) in an amount of 95% by mass or more, more preferably 97% by mass or more. more than 90% by mass is more preferred. The total amount (100% by mass) of the mixed yarn may be composed of continuous reinforcing fibers (A2) and thermoplastic resin fibers (B2).

In the mixed yarn, the impregnation rate of the thermoplastic resin fibers (B2) into the continuous reinforcing fibers (A2) is preferably 0 to 20%. Impregnation proceeds more effectively during molding by adjusting the amount to be at least the above lower limit. Moreover, by making it below the said upper limit, it tends to be flexible and excellent in shape retention.
The impregnation rate is preferably 1% or more, and may be 2% or more. Also, the impregnation rate is preferably 18% or less, more preferably 15% or less, and even more preferably 10% or less.

In the mixed yarn, the degree of dispersion of the continuous reinforcing fibers (A2) with respect to the thermoplastic resin fibers (B2) is preferably 90% or more, more preferably 91% or more, and further preferably 92% or more. Preferably, it is more preferably 93% or more. The upper limit may be 100% or 99% or less. By increasing the degree of dispersion in this way, it is possible to effectively suppress fraying, slack, and breakage.
In the present invention, the degree of dispersion is an index of whether the continuous reinforcing fibers (A2) and the thermoplastic resin fibers (B2) are uniformly mixed. means The dispersity is measured according to the method described in Examples below.

The continuous reinforcing fibers (A2) used for the mixed yarn refer to fibers exceeding 50 mm, for example, 10 cm or more, and more than 1 m practically. The cross section of the continuous reinforcing fibers (A2) in the present invention may be circular or flat. It may also be cut to a shorter length when it is molded into a material.

The continuous reinforcing fibers (A2) used in the present invention include inorganic fibers such as glass fibers, carbon fibers, alumina fibers, boron fibers, ceramic fibers, metal fibers (steel fibers, etc.), and vegetable fibers (Kenaf, bamboo fibers, etc.), cellulose fibers (including cellulose nanofibers), aramid fibers, polyoxymethylene fibers, aromatic polyamide fibers, polyparaphenylenebenzobisoxazole fibers, and organic fibers such as ultra-high molecular weight polyethylene fibers. . Among them, it preferably contains at least one of carbon fiber, aramid fiber and glass fiber, more preferably contains at least one of carbon fiber and glass fiber, and further preferably contains at least one of carbon fiber.
The continuous reinforcing fibers (A2) may be recycled fibers, particularly recycled carbon fibers.

The continuous reinforcing fibers (A2) used in the preferred embodiment of the present invention are preferably treated with a treating agent. The details of the treatment agent are the same as those described in the reinforcing fiber (A1) described above, and the preferred range is also the same.

The content of the continuous reinforcing fibers (A2) in the mixed yarn is preferably 30 to 80% by mass of the mixed yarn. By making it more than the said lower limit, there exists a tendency for it to be excellent by the strength of a molded article. Further, by setting the content to the above upper limit or less, the impregnation proceeds more effectively during molding.
The content of the continuous reinforcing fibers (A2) is preferably 30% by mass or more, more preferably 35% by mass or more, and even more preferably 40% by mass or more. Moreover, the content is preferably 80% by mass or less, more preferably 75% by mass or less, and even more preferably 70% by mass or less.

The content of the continuous reinforcing fibers (A2) in the mixed yarn is preferably 17 to 75% by volume of the mixed yarn. By making it more than the said lower limit, there exists a tendency for it to be more excellent by the intensity|strength of the molded article obtained. In addition, when the amount is equal to or less than the above upper limit, there is a tendency that the impregnating property of the molded product is more excellent.
The content of the continuous reinforcing fibers (A2) is preferably 17% by volume or more, more preferably 25% by volume or more, and even more preferably 30% by volume or more. The content is preferably 70% by volume or less, more preferably 65% by volume or less, and even more preferably 60% by volume or less.
Only one type of the continuous reinforcing fibers (A2) may be used, or two or more types may be used. When two or more kinds are used, the total amount is preferably within the above range.

The thermoplastic resin fiber (B2) used in the present invention can be formed from a thermoplastic resin composition. The details of the thermoplastic resin composition may be the same as those described in the thermoplastic resin fiber (B1).
As the thermoplastic resin (b2) used for the thermoplastic resin fiber (B2), the same resin as described for the thermoplastic resin (b1) can be used. In particular, the mixed yarn preferably contains at least one thermoplastic resin selected from polyamide resins and polyolefin resins as the thermoplastic resin (b2). In addition, the mixed yarn is composed of structural units derived from diamine and structural units derived from dicarboxylic acid as the thermoplastic resin (b2), and 50 mol% or more of the structural units derived from diamine are derived from xylylenediamine. It preferably contains a polyamide resin that These more preferred ranges are the same as those described for the thermoplastic resin (b1).

The melting point of the thermoplastic resin (b2) is preferably 130 to 320°C. By making it more than the said lower limit, there exists a tendency for the molded article obtained to be excellent in heat resistance. Moreover, by making it below the said upper limit, there exists a tendency for it to be excellent by molding processability.
The melting point is preferably 130° C. or higher, more preferably 140° C. or higher, and even more preferably 150° C. or higher. In addition, the melting point is preferably 320° C. or lower, more preferably 310° C. or lower, even more preferably 300° C. or lower, even if it is 280° C. or lower, 270° C. or lower, or 250° C. or lower. good.

In the present invention, the difference between the melting point of the thermoplastic resin (b2) constituting the thermoplastic resin fiber (B2) and the melting point of the thermoplastic resin (b1) constituting the thermoplastic resin fiber (B1) is 2 to 70. °C is preferred. By making it equal to or higher than the above lower limit, there is a tendency for the strength of the standing portion to be more excellent. Moreover, by making it below the said upper limit, there exists a tendency for it to be excellent by molding processability.
The difference in melting points is preferably 2° C. or more, more preferably 5° C. or more, and even more preferably 10° C. or more. The difference in melting point is preferably 70° C. or less, more preferably 60° C. or less, and even more preferably 50° C. or less.

The ratio of the volume (Vt) of the thermoplastic resin fiber (B2) to the volume (Vc) of the continuous reinforcing fiber (A2) in the mixed yarn used in the present invention is a ratio of Vt/Vc of 0.3 or more. It is preferably 0.5 or more, more preferably 0.8 or more. The upper limit is preferably 10 or less, more preferably 5 or less, and even more preferably 3 or less.

The thermoplastic resin fiber (B1) in the present invention is preferably a thermoplastic resin fiber having a treating agent for thermoplastic resin fibers on its surface. These details can be referred to the description of paragraphs 0064 to 0065 of WO 2016/159340, and the contents thereof are incorporated herein.
Since the thermoplastic resin fibers (B1) contain the surface treatment agent, breakage of the thermoplastic resin fibers (B1) can be suppressed in the manufacturing process of the mixed yarn and the subsequent processing process.
The amount of the surface treatment agent for the thermoplastic resin fiber (B1) is, for example, 0.1 to 2.0% by mass of the thermoplastic resin fiber (B1). The lower limit is preferably 0.5% by mass or more, more preferably 0.8% by mass or more. The upper limit is preferably 1.8% by mass or less, more preferably 1.5% by mass or less. By setting it as such a range, the dispersion of the thermoplastic resin fibers (B1) is improved.
The type of the surface treatment agent is not particularly limited as long as it has a function of converging the thermoplastic resin fibers (B2) and the continuous reinforcing fibers (A2). Treatment agents include ester compounds, alkylene glycol compounds, polyolefin compounds, phenyl ether compounds, polyether compounds, silicone compounds, polyethylene glycol compounds, amide compounds, sulfonate compounds, phosphate compounds, carboxy Rate compounds and combinations of two or more thereof are preferred, and ester compounds are more preferred.

The thermoplastic resin fiber (B2) also preferably has a moisture content of 5% or less, more preferably 4% or less, even more preferably 3% or less, measured according to JIS L 1096. % or less. The lower limit may be 0%, but 0.001% or more is practical.

The method of treating the thermoplastic resin fibers (B2) with the surface treatment agent is not particularly defined as long as the intended purpose can be achieved. For example, the thermoplastic resin fiber (B2) may be added with a surface treatment agent dissolved in a solution to adhere the treatment agent to the surface of the thermoplastic resin fiber (B2). Alternatively, the treating agent can be air-blown onto the surface of the thermoplastic resin fibers (B2).

The thermoplastic resin fibers (B2) in the mixed yarn may be twisted short fibers or the like, but are usually continuous thermoplastic resin fibers. A continuous thermoplastic fiber is defined as a fiber greater than 50 mm, and practically greater than 1 m. The cross section of the thermoplastic resin fiber (B2) in the present invention may be circular or flat.

The content of the thermoplastic resin fiber (B2) in the mixed yarn is preferably 20 to 70% by mass of the mixed yarn. By making the amount equal to or higher than the lower limit, the impregnation proceeds more effectively during molding. In addition, when the content is equal to or less than the above upper limit, the resulting molded article tends to be excellent in strength.
The content of the thermoplastic resin fibers (B2) is preferably 20% by mass or more, more preferably 25% by mass or more, and even more preferably 30% by mass or more. The content is preferably 70% by mass or less, more preferably 65% by mass or less, and even more preferably 60% by mass or less.
Only one kind of the thermoplastic resin fiber (B2) may be used, or two or more kinds thereof may be used. When two or more kinds are used, the total amount is preferably within the above range.

In the present invention, when the mixed yarn is tape-shaped, its thickness is preferably 10 μm or more, more preferably 30 μm or more, even more preferably 50 μm or more, and preferably 100 μm or more. Even more preferable. The upper limit is preferably 5000 μm or less, more preferably 1000 μm or less, even more preferably 500 μm or less, and even more preferably 250 μm or less.
In the present invention, when the mixed yarn is tape-shaped, the width is preferably 0.5 mm or more, more preferably 1 mm or more, further preferably 3 mm or more, and 5 mm or more. is more preferable, and 7 mm or more is even more preferable. The upper limit is preferably 100 mm or less, more preferably 50 mm or less, and even more preferably 20 mm or less.

The method for producing the mixed yarn is not particularly defined, but the thermoplastic resin composition is melt-extruded with an extruder, extruded into a strand, stretched while being wound with a roll, and wound on a winding body. A continuous thermoplastic resin fiber bundle is obtained.
Each fiber is pulled out from the wound body of the continuous thermoplastic resin fiber (B2) obtained above and the wound body of the continuous reinforcing fiber (A2) prepared in advance, and opened by air blowing while passing through a plurality of guides. do. The continuous thermoplastic resin fibers (B2) and the continuous reinforcing fibers (A2) are bundled while being opened. At this time, it is preferable to apply an air blow while passing through a plurality of guides to advance uniformity while preparing the mixed yarn in a tape shape. At the time of this air blow, the continuous reinforcing fibers (A2) and the continuous thermoplastic resin fibers (B2) may be surface-treated with the above-described treatment agent, or the fibers of the fiber bundle that have been surface-treated in advance are unwound from the wound body and used. may

In the present invention, the mixed yarn is preferably produced using a continuous thermoplastic resin fiber bundle and a continuous reinforcing fiber bundle. Total fineness of fibers used to produce one mixed yarn (total fineness of continuous thermoplastic resin fibers (B2) used to produce one mixed yarn and total fineness of continuous reinforcing fibers (A2) is preferably 1,000 to 100,000 dtex, more preferably 1,500 to 50,000 dtex, even more preferably 2,000 to 50,000 dtex, and particularly preferably 3,000 to 30,000 dtex.

The total number of fibers used to manufacture one mixed yarn (the total number of fibers of the continuous thermoplastic resin fibers (B2) and the total number of fibers of the continuous reinforcing fibers (A2)) is the number of fibers is preferably from 100 to 100,000 f, more preferably from 1,000 to 100,000 f, still more preferably from 1,500 to 70,000 f, and even more preferably from 2,000 to 20,000 f. Within this range, the blending property of the blended yarn is improved, and a molded article having superior physical properties and texture can be obtained. In addition, there are few regions where any one of the fibers is biased, and the fibers tend to disperse more uniformly.

The mixed yarn used in the present invention may be twisted. However, it is preferable that the mixed yarn used in the present invention is not twisted (meaning that the mixed yarn is not actively twisted).

The mixed yarn used in the present invention may be partially impregnated. A mixed fiber yarn that is partially impregnated uniformly over the entire fiber may be used, or a mixed fiber yarn in which impregnated portions and non-impregnated portions are alternately present in the width direction of the fiber may be used.

<Shape retention>
In the present invention, the shape of the mixed yarn is retained by the thermoplastic resin fibers (B3) in a state where the mixed yarn is arranged on a layer such as a nonwoven fabric. By retaining the shape in this manner, the orientation of the continuous reinforcing fibers (A2) in the mixed yarn tends to be properly maintained, and a molded article having excellent strength can be obtained. Here, it is preferable that the mixed yarn is provided so as to correspond to the erected portion of the mold. Further, it goes without saying that the mixed yarn may be arranged in a corresponding portion other than the portion to be the erected portion.
The thermoplastic resin fiber (B3) used in the present invention is usually made of a thermoplastic resin composition containing the thermoplastic resin (b3) as a main component. The thermoplastic resin composition that is the raw material of the thermoplastic resin fiber (B3) is usually 50% by mass or more of the thermoplastic resin (b3), and preferably 60% by mass or more of the thermoplastic resin (b3). , 70% by mass or more may be the thermoplastic resin (b3). The thermoplastic resin fibers (B3) have lower strength (eg, elastic modulus) than the reinforcing fibers (A1) and the continuous reinforcing fibers (A2).
As the thermoplastic resin (b3), widely known ones can be used, for example, polyolefin resins such as polyethylene and polypropylene, polyester resins such as polyamide resins, polyethylene terephthalate and polybutylene terephthalate, polycarbonate resins, and polyoxymethylene resins. , polyetherketone, polyethersulfone, thermoplastic polyetherimide, and aramid. In the present invention, the thermoplastic resin (b3) is preferably a polyamide resin, a polyester resin, or an aramid resin, more preferably a polyamide resin. As a specific example of the polyamide resin, the polyamide resin described in the above thermoplastic resin fiber (B1) can be preferably employed. In addition, the thermoplastic resin composition that is the raw material of the thermoplastic resin fiber (B3) may contain components other than the thermoplastic resin, and these are synonymous with those described for the thermoplastic resin fiber (B1). and the preferred range is also the same.

The melting point of the thermoplastic resin (b3) is preferably 180° C. or higher, more preferably 190° C. or higher, and even more preferably 200° C. or higher, although it depends on the type of resin used. Also, the melting point is preferably 320° C. or lower, more preferably 310° C. or lower, and even more preferably 300° C. or lower.
The melting point is measured by the method described in Examples below.
In the present invention, the melting point of the thermoplastic resin (b3) constituting the thermoplastic resin fiber (B3) is preferably higher than the melting point of the thermoplastic resin (b2) constituting the thermoplastic resin fiber (B2). , more preferably 2° C. or more, more preferably 5° C. or more, and even more preferably 10° C. or more. With the above range, the accuracy of the shape-retaining position tends to be more excellent. Further, the difference between the melting point of the thermoplastic resin (b3) and the melting point of the thermoplastic resin (b2) is preferably 100° C. or less, more preferably 80° C. or less, and preferably 70° C. or less. More preferred. By setting it as the said range, there exists a tendency for the formability of an erection site|part to be more excellent.
In the present invention, the melting point of the thermoplastic resin (b3) constituting the thermoplastic resin fiber (B3) is higher than the melting point of the thermoplastic resin (b1) constituting the thermoplastic resin fiber (B1). , more preferably 10°C or more, and even more preferably 20°C or more. By setting the content within the above range, the flow direction of the molten resin is controlled, and the impregnation property of the resin tends to be more excellent. The difference between the melting point of the thermoplastic resin (b3) and the melting point of the thermoplastic resin (b1) is preferably 200°C or less, more preferably 150°C or less. By setting it as the said range, the molded article excellent by surface appearance is obtained.

The length of the thermoplastic resin fiber (B3) used in the present invention is not particularly specified as long as the shape of the mixed yarn can be maintained, but from the viewpoint of ease of processing, thermoplastic resin fibers having a length of 6 mm or more are preferable. , more preferably thermoplastic resin fibers having a length of 20 mm or more. In the present invention, one thermoplastic resin fiber (B3) may be used to retain the shape of the mixed yarn, or two or more thermoplastic resin fibers (B3) may be used to retain the shape of different parts of the mixed yarn. can be anything. Furthermore, two or more bundles of thermoplastic resin fibers (B3) may be used to retain the shape of the mixed yarn.
The fineness of the thermoplastic resin fiber (B3) can be, for example, 10-200 dtex, preferably 50-150 dtex, more preferably 100-150 dtex. The thermoplastic resin fibers (B3) may be used as they are, or may be used after being twisted with a plurality of strands such as two strands or three strands.

[Manufacturing process]
<Heating>
The production method of the present invention includes heating the material from the layer side of the nonwoven fabric or the like at a temperature not higher than the melting point of the thermoplastic resin fibers (B3), and From the side, it includes heating at a temperature above the melting point of the thermoplastic resin (b3) that constitutes the thermoplastic resin fiber (B3). With such a configuration, the thermoplastic resin fibers (B3) are less likely to melt on the side closer to the layer of the nonwoven fabric or the like, and the shape retention of the nonwoven fabric or the like and the mixed yarn can be easily maintained. On the other hand, on the mixed yarn side, the thermoplastic resin fibers (B3) are moderately melted, so that the mixed yarn and the layer of the nonwoven fabric or the like can easily enter the upstanding portion.
Here, the layer side of the nonwoven fabric or the like means the side on which the mixed yarn is provided on the layer of the nonwoven fabric or the like in the material used in the present invention, but the mixed yarn is not provided. For example, it is the A side in FIG. Further, the side where the mixed yarn is provided on a layer such as a nonwoven fabric, and the side on which the mixed yarn is provided means the side on which the mixed yarn is provided. For example, it is the B side in FIG.
In the present invention, more than 99% by mass of the thermoplastic resin fiber (B1), more than 99% by mass of the thermoplastic resin fiber (B2), and the mixed yarn of the thermoplastic resin fiber (B3) are arranged by the heating. More than 50% by mass and 90% by mass or less (preferably 55 to 80% by mass, more preferably 55 to 75% by mass) of the portion exposed to the side, and thermoplastic resin fibers (B3) On the layer side such as nonwoven fabric More than 1% by mass and 50% by mass or less (preferably 10 to 40% by mass, more preferably 15 to 35% by mass) of the exposed portion is melted, and molding is performed in the melted state. These molten state ratios are measured by the method described in Examples below. In particular, in the present invention, the difference between the melting rate of the portion exposed on the side on which the mixed yarn is arranged and the melting rate of the portion exposed on the layer side of the nonwoven fabric, etc. is preferably 20 to 50% by mass, preferably 25 to 45%. % by mass is more preferred. Molding in a state with such a melting difference tends to result in a molded product with higher precision and strength.

The heating temperature from the layer side of the nonwoven fabric is a temperature below the melting point of the thermoplastic resin fiber (B3), preferably -1°C or below, more preferably -4°C or below. When the thickness is equal to or less than the above upper limit, the accuracy of the shape retention is excellent, and the nonwoven fabric layer material tends to be introduced into the erected portion together with the mixed filament yarn material. The lower limit of the heating temperature from the nonwoven fabric side is preferably -10°C or higher, more preferably -8°C or higher. A sufficient amount of the material tends to be introduced more easily into the erected portion by making it equal to or greater than the lower limit.
Heating from the side of the nonwoven fabric or the like can be performed by, for example, an IR heater, a block heater, hot air, or microwaves.

The heating temperature from the shape-retaining side of the mixed yarn is a temperature equal to or higher than the melting point of the thermoplastic resin fiber (B3), preferably +1°C or higher, more preferably +3°C or higher. When the thickness is equal to or higher than the above lower limit, the melted mixed yarn is introduced into the erected portion with fewer voids, and the strength of the erected portion tends to be more excellent. The upper limit of the heating temperature from the shape-retaining side of the mixed yarn is preferably +10°C or lower than the melting point, more preferably +7°C or lower than the melting point. By making it equal to or less than the above lower limit, a sufficient amount of material is introduced into the erected portion, and the strength of the erected portion tends to be more excellent.
Heating from the mixed yarn side can be performed by, for example, an IR heater, a block heater, hot air, or microwaves.

In the manufacturing method of the present invention, the molded article can be molded by using a mold, a silicone mold, or the like. Preferably, it can be molded by press working using a mold. Compression molding can also be performed by vacuuming.
FIG. 2 is a schematic diagram showing an example of the press working process in the present invention, wherein 1 is a layer of nonwoven fabric or the like, 2 is a mixed yarn, 4 is a lower mold, 5 is an upper mold, showing. FIG. 3 is an enlarged view of the circled portion indicated by the dotted line in FIG. In FIG. 2, a mixed yarn 2 is placed on the surface of a layer 1 such as a non-woven fabric, and a shape-retaining material is placed with thermoplastic resin fibers (B3) (not shown) in a lower mold 4, and an upper mold is placed. 5 is used for press working. In the present invention, both can be easily adhered to each other with high strength by press working. Furthermore, in the present invention, the reinforcing fibers (A1) and the continuous reinforcing fibers (A2) are dispersed in the layer 1 such as a nonwoven fabric and the mixed yarn 2, respectively. is easily impregnated into the reinforcing fibers (A1) and the continuous reinforcing fibers (A2), and as a result, a molded product can be molded even using a material that has not been pre-impregnated. Of course, molding may be performed in two or more steps.
In the present invention, the total volume of the mixed yarns 2 is preferably less than the volume of the concave portion of the upper mold 5 . In particular, when the total volume of the mixed yarns 2 is less than the volume of the concave portion of the upper mold 5 (for example, by about 2 to 20% by volume), part of the material of the layer 1 such as a nonwoven fabric is removed from the upper mold 5. It becomes easier to enter the concave portion (1′ in FIGS. 2 and 3), and the adhesion between the layer 1 such as the nonwoven fabric and the mixed yarn 2 can be further improved, and the strength of the standing portion can be further increased. The molded product of the present invention may have other portions than the layer 1 of nonwoven fabric and the mixed yarn 2, but such other portions may be simultaneously formed by press working, It may be molded separately.
The positions of the layer 1 of the nonwoven fabric or the like and the mixed yarn 2 may be reversed with respect to the lower mold and the upper mold. That is, as shown in FIG. 4, the mixed yarn 2 is placed on the surface of a layer 1 such as a non-woven fabric, and the shape-retaining material with thermoplastic resin fibers (B3) (not shown) is placed with the mixed yarn 2 side facing down. It may be arranged so as to be on the mold 4 side, and the upper mold 5 may be overlapped for molding. Even in this case, the thermoplastic resin is easily impregnated into the reinforcing fibers (A1) and the continuous reinforcing fibers (A2), and both the reinforcing fibers (A1) and the reinforcing fibers (A2) are introduced into the standing portion. The erected portions are formed so that the reinforcing fibers (A2) push up the layer 1 of the nonwoven fabric.

The press molding pressure is preferably 0.5 to 10 MPa, more preferably 0.8 to 5 MPa. In particular, in the conventional method using an impregnated material, molding was usually performed at a pressure of about 2 MPa to 5 MPa, but in the method of the present invention, molding is possible even at a pressure of about 0.8 to 2.0 MPa. be.
The press molding time is preferably 1 to 20 minutes, more preferably 3 to 15 minutes. The present invention is particularly valuable in that the impregnation of the thermoplastic resin can proceed appropriately even if the press molding time is set to about 3 to 5 minutes.

[Standing part]
The molded article obtained by the present invention has a standing portion (6 in FIG. 2). A rib or the like corresponds to the standing portion. The strength of the erected portion tends to be a problem, but in the present invention, the strength of the erected portion can be increased by using the above materials and appropriately adjusting the heating temperature.
The standing portion 6 is a portion that is provided in a direction that rises from a portion derived from a layer such as a nonwoven fabric. The rising direction may be substantially perpendicular to the portion derived from the layer of the nonwoven fabric or the like, or may have an angle within the scope of the present invention. As an example of the substantially vertical direction, there is an example in which the rising direction is, for example, 89° to 91°. In addition, if the upper die is designed to be opened after pressing, it is possible to form angled ribs and ribs with complicated shapes. The upper mold can be designed to open in two or more than three.

In the present invention, it is preferable to arrange so that the fiber length direction of the mixed yarn is present most in the direction perpendicular to the narrowest portion of the erected portion. With such a configuration, the mixed yarn tends to flow into the standing portion more effectively.

It is preferable that the standing portion 6 used in the present invention has a height of 3 to 20 mm. By making it equal to or higher than the above lower limit, there is a tendency that the strength of the molded product is achieved more effectively. Further, by making the thickness equal to or less than the above upper limit, the performance of the standing portion 6 (particularly ribs) can be sufficiently exhibited, and the weight of the molded product can be reduced. Height here means vertical height from a layer such as a nonwoven. The height of the standing portion is preferably 3 mm or more, more preferably 4 mm or more, and even more preferably 5 mm or more. Also, the height of the standing portion is preferably 20 mm or less, more preferably 17 mm or less, and even more preferably 15 mm or less.

The standing portion 6 used in the present invention preferably has a volume of 0.1 to 20 cm ³ . By making it equal to or higher than the above lower limit, there is a tendency that the strength of the molded product is achieved more effectively. Further, by setting the content to be equal to or less than the above upper limit, it is possible to further reduce the weight of the molded article.
The volume of the standing portion is preferably 0.1 cm ³ or more, more preferably 0.5 cm ³ or more, and even more preferably 1 cm ³ or more. The content is preferably 20 cm ³ or less, more preferably 15 cm ³ or less, even more preferably 10 cm ³ or less, and even more preferably 8 cm ³ or less.

Furthermore, the ratio of the volume of the standing portion to the total volume of the molded product is preferably 1 to 20%. By making it equal to or higher than the above lower limit, there is a tendency that the strength of the molded product is achieved more effectively. Further, by setting the content to be equal to or less than the above upper limit, it is possible to further reduce the weight of the molded product.
The volume ratio of the standing portion is preferably 1% or more, more preferably 3% or more, and even more preferably 5% or more. Also, the content is preferably 20% or less, more preferably 17% or less, and even more preferably 14% or less.

In addition, it is preferable that the width of the opening of the erected portion (meaning the position where it is joined to the main part of the molded product, for example, the portion indicated by symbol X in FIG. 3) is 0.5 to 10 mm. By making it equal to or higher than the above lower limit, it becomes easier for the mixed yarn and the nonwoven fabric component to flow into the standing portion. Further, by setting the content to be equal to or less than the above upper limit, it is possible to further reduce the weight of the molded product.
The width of the opening of the standing portion is preferably 0.5 mm or more, more preferably 1 mm or more, still more preferably 2 mm or more, and further preferably 4 mm or more, 5 mm or more, or 6 mm or more. There may be. The content is preferably 10 mm or less, more preferably 9 mm or less, even more preferably 8 mm or less, and may be 5 mm or less, or 4 mm or less.

<Application of molded product>
The molded article of the present invention can be widely used as a molded article having standing portions. The molded product here may be a part as well as a finished product.
The molded article of the present invention includes, for example, personal computers, OA equipment, AV equipment, electrical and electronic equipment such as mobile phones, optical equipment, precision equipment, toys, household and office electrical appliances, parts and housings, automobiles, aircraft , can be suitably used for parts of ships and the like.

EXAMPLES The present invention will be described more specifically with reference to examples below. The materials, usage amounts, ratios, processing details, processing procedures, etc. shown in the following examples can be changed as appropriate without departing from the gist of the present invention. Accordingly, the scope of the present invention is not limited to the specific examples shown below.

[Nonwoven fabric (layer)]
<Type of reinforcing fiber (A1)>
CF: Carbon fiber, manufactured by Mitsubishi Chemical Corporation, Pyrofil-TR-50S-12000-AD, 8000 dtex, number of fibers: 12000 f, surface-treated with epoxy resin GF: Continuous glass fiber, manufactured by Nitto Boseki Co., Ltd., ECG 75 1/0 0.7Z, fineness 687dtex, number of fibers 400f, surface-treated with a sizing agent <Number average fiber length (mm) of reinforcing fibers (A1)>
100 arbitrarily selected samples were taken out and their numerical average value was obtained.

<Type of thermoplastic resin (b1)>
PP: Polypropylene resin, Novatec FY6 manufactured by Nippon Polypropylene Co., Ltd.
MXD6: meta-xylylene adipamide resin (manufactured by Mitsubishi Gas Chemical Company, Inc., grade S6001), number average molecular weight 16,800
MP10: xylylene sebacamide resin synthesized according to the following synthesis example, number average molecular weight 15400

<<Synthesis example of MP10>>
10 kg (49.4 mol) of sebacic acid (TA grade manufactured by Ito Oil Co., Ltd.) and acetic acid were placed in a reaction vessel equipped with a stirrer, partial condenser, total condenser, thermometer, dropping funnel, nitrogen inlet tube, and strand die. 11.66 g of sodium/sodium hypophosphite monohydrate (molar ratio = 1/1.5) was charged, and after sufficient nitrogen substitution, the inside of the system was stirred under a small amount of nitrogen stream to 170 g. It melted by heating up to °C.
6.647 kg of mixed xylylenediamine having a molar ratio of 70/30 of meta-xylylenediamine (manufactured by Mitsubishi Gas Chemical Co., Ltd.) and para-xylylenediamine (manufactured by Mitsubishi Gas Chemical Co., Ltd.) (34 kg of meta-xylylenediamine) 16 mol, para-xylylenediamine 14.64 mol) was added dropwise to molten sebacic acid with stirring, and the internal temperature was continuously raised to 240°C over 2.5 hours while the condensed water produced was discharged out of the system. I warmed up.
After the dropwise addition was completed, the internal temperature was increased, and when the temperature reached 250°C, the pressure in the reaction vessel was reduced, and the internal temperature was further increased to continue the melt polycondensation reaction at 255°C for 20 minutes. Thereafter, the inside of the system was pressurized with nitrogen, and the obtained polymer was taken out from the strand die and pelletized to obtain polyamide resin MP10.
The obtained MP10 had a melting point of 213° C. and a number average molecular weight of 15,400.

<Melting point of thermoplastic resin (b1)>
A differential scanning calorimeter (DSC) was used to measure the melting point, the sample amount was about 1 mg, nitrogen was flowed at 30 mL/min as the atmospheric gas, and the temperature was raised from room temperature at a rate of 10°C/min. The melting point was determined from the peak top temperature of the endothermic peak observed when the material was heated to a temperature above the melting point and melted.
As a differential scanning calorimeter (DSC), DSC-60 manufactured by Shimadzu Corporation was used.

<Method for manufacturing nonwoven fabric>
The thermoplastic resin (b1) shown in the table below is melt-extruded with a single-screw extruder having a screw with a diameter of 30 mm, extruded into a strand from a 60-hole die, and stretched while being wound on a roll to form a continuous thermoplastic resin. 800 m of the fiber bundle was wound on the winding body. The melting temperature was the melting point of the continuous thermoplastic resin (b1) +15°C. The obtained thermoplastic resin fiber (B1) had a number average fiber diameter of 20 μm.
A deep vat is filled with an oil agent (polyoxyethylene hardened castor oil (manufactured by Kao, Emanone 1112)), and a rubber-coated roller is placed so that the lower part of the roller is in contact with the oil agent. , the oil was always adhered to the roller surface. The surface of the continuous thermoplastic resin fiber was coated with an oil agent by bringing the continuous thermoplastic resin fiber into contact with the roller, and the continuous thermoplastic resin fiber was wound again on the winding body.
A nonwoven fabric was produced by the method described in Example 1 of JP-A-2014-224333, and heat-pressed with heat rolls heated to a melting point of +5°C to obtain the desired nonwoven fabric. The thermoplastic resin fiber (B1) was used after being cut into a number average fiber length of 7.6 mm.
The obtained nonwoven fabric had a content of reinforcing fibers (A1) of 41% by volume and a content of thermoplastic resin fibers (B1) of 59% by volume.

<Density (mg/m ³ )>
A 50 mm×50 mm piece was cut from the obtained non-woven fabric (layer), the dimensions were measured with a vernier caliper and a micrometer, and the mass was precisely weighed. Density was calculated from volume/mass. It was repeated 5 times and the number average value was obtained.

<Puncture Strength (N)>
A 50 mm×50 mm cut test piece was made from the obtained nonwoven fabric (layer). Using a tensile tester Strograph EII manufactured by Toyo Seiki Co., Ltd., an aluminum needle with a tip radius of 50 μm was used to pierce the nonwoven fabric (layer) obtained in compression mode, and the applied load was measured. It was repeated 5 times and taken as the number average value.

<Thickness (mm)>
The nonwoven fabric (layer) was measured at any five locations with a micrometer, and the numerical average was obtained.

<Impregnation rate (%) in nonwoven fabric (layer)>
The nonwoven fabric (layer) to be measured was cut, cut in a cross section perpendicular to the layer of the nonwoven fabric (layer), the cross section was polished, and the cross section was photographed using an ultra-depth color 3D shape measuring microscope. A cross section of the prepared sample was observed with a digital microscope. A region of the continuous reinforcing fiber (A1) impregnated with the thermoplastic resin (b1) was selected from the obtained cross-sectional photograph using image analysis software ImageJ, and the area thereof was measured. The impregnation rate was shown as the area of the continuous reinforcing fiber (A1) impregnated with the thermoplastic resin (b1)/cross-sectional area (unit: %).
A VK-9500 (controller unit)/VK-9510 (measurement unit) (both manufactured by KEYENCE) was used as an ultra-deep color 3D shape measuring microscope.

[Mixed yarn]
<Types of continuous reinforcing fibers (A2)>
CF: Continuous carbon fiber, manufactured by Mitsubishi Chemical Corporation, Pyrofil-TR-50S-12000-AD, 8000 dtex, number of fibers: 12000 f, surface-treated with epoxy resin GF: Continuous glass fiber, manufactured by Nitto Boseki Co., Ltd., ECG 75 1/ 0 0.7Z, fineness 687dtex, number of fibers 400f, surface treated with sizing agent

<Type of thermoplastic resin (b2)>
PP: Polypropylene resin, Novatec FY6 manufactured by Nippon Polypropylene Co., Ltd.
MXD6: meta-xylylene adipamide resin (manufactured by Mitsubishi Gas Chemical Company, Inc., grade S6001), number average molecular weight 16,800
MP10: xylylene sebacamide resin synthesized by the above synthesis example, number average molecular weight 15400

<Melting point (°C) of thermoplastic resin (b2)>
It was measured by the same method as the melting point (° C.) of the thermoplastic resin (b1).

<Production of continuous thermoplastic resin fiber (B2)>
The thermoplastic resin (b2) shown in the table below is melt-extruded with a single-screw extruder having a screw with a diameter of 30 mm, extruded into a strand from a 60-hole die, and stretched while being wound on a roll to form a continuous thermoplastic resin. 800 m of the fiber bundle was wound on the winding body. The melting temperature was the melting point of the continuous thermoplastic resin +15°C.
A deep vat is filled with an oil agent (polyoxyethylene hardened castor oil (manufactured by Kao, Emanone 1112)), and a rubber-coated roller is placed so that the lower part of the roller is in contact with the oil agent. , the oil was always adhered to the roller surface. The surface of the continuous thermoplastic resin fiber was coated with an oil agent by bringing the continuous thermoplastic resin fiber into contact with the roller, and the continuous thermoplastic resin fiber was wound again on the winding body. The obtained thermoplastic resin fibers (B2) had a number average fiber diameter of 20 μm.

<Method for producing mixed yarn>
A mixed yarn was produced according to the following method.
Each fiber is pulled out from a winding body of continuous thermoplastic resin fibers (B2) having a length of 1 m or more and a winding body of continuous reinforcing fibers (A2) having a length of 1 m or more, and a plurality of guides are provided. Opening was performed by an air blow while passing through. While opening the fibers, the continuous thermoplastic resin fibers (B2) and the continuous reinforcing fibers (A2) were made into one bundle, and air blow was applied while passing through a plurality of guides to promote uniformity.
The mixed yarn thus obtained had a fineness of about 13,000 dtex and a fiber count of about 13,500 f using carbon fibers, and a fineness of about 15,000 dtex and a fiber count of about 10,000 f using glass fibers, and a combination of continuous thermoplastic resin fibers and continuous reinforcing fibers. The volume ratio is 1:1, and the ratio of continuous reinforcing fibers is 61% by mass (44% by volume) for mixed yarn using carbon fiber and 69% by mass (50% by volume) for mixed yarn using glass fiber. )Met. The resulting mixed yarn had a width of 10 mm and a thickness of 0.2 mm.

<Impregnation rate (%) in mixed yarn>
The mixed yarn to be measured was cut and embedded in epoxy resin, the surface corresponding to the cross section of the mixed yarn was polished, and the cross section was photographed using an ultra-depth color 3D shape measuring microscope. A cross section of the prepared sample was observed with a digital microscope. A region of the continuous reinforcing fiber (A2) impregnated with the thermoplastic resin (b2) was selected from the obtained cross-sectional photograph using image analysis software ImageJ, and the area thereof was measured. The impregnation rate was shown as the area of the continuous reinforcing fiber (A2) impregnated with the thermoplastic resin (b2)/cross-sectional area (unit: %).
A VK-9500 (controller unit)/VK-9510 (measurement unit) (both manufactured by KEYENCE) was used as an ultra-deep color 3D shape measuring microscope.

超深度カラー３Ｄ形状測定顕微鏡は、ＶＫ－９５００（コントローラー部）／ＶＫ－９５１０（測定部）（キーエンス製）を使用した。 <Dispersion degree (%) in mixed yarn>
The mixed yarn was embedded in an epoxy resin, the cross section perpendicular to the longitudinal direction of the mixed yarn was polished, and the cross-sectional view was photographed using an ultra-deep color 3D shape measuring microscope. As shown in FIG. 5, in the photographed image, six auxiliary lines are drawn radially at equal intervals, and the length of the continuous reinforcing fiber (A2) region on each auxiliary line is a1, a2, a3 ... ai(i =n). Also, the lengths of the regions of the continuous thermoplastic resin fibers (B2) on each auxiliary line were measured as b1, b2, b3, . . . bi (i=m). Based on the result, the degree of dispersion was calculated by the following formula.

A VK-9500 (controller unit)/VK-9510 (measuring unit) (manufactured by Keyence) was used as an ultra-deep color 3D shape measuring microscope.

[Shape-retaining thread (thermoplastic resin fiber (B3))]
<Type of thermoplastic resin (b3) used for thermoplastic resin fiber (B3)>
PA66: Polyamide 66, manufactured by Toray Industries, Inc., CM3001N
MXD6: meta-xylylene adipamide resin (manufactured by Mitsubishi Gas Chemical Company, Inc., grade S6001), number average molecular weight 16,800
PE: Polyethylene resin, manufactured by Gunze, Gunze GPT-30
Aramid: Aramid resin, FRP-ZONE. Purchased from COM.

<Melting point (°C) of thermoplastic resin (b3)>
It was measured by the same method as the melting point (° C.) of the thermoplastic resin (b1).

<Method for producing shape-retaining yarn (thermoplastic resin fiber (B3))>
A thermoplastic resin (b3) shown in the table below was used and fibrous according to the following method.
The thermoplastic resin (b3) is melt-extruded with a single-screw extruder having a screw of 30 mmφ, extruded into a strand from a 60-hole die, stretched while being wound on a roll, and wound on a roll. A resin fiber bundle was obtained. The melting temperature was the melting point +20°C. The obtained thermoplastic resin fiber (B3) had a number average fiber diameter of 20 μm.

[Examples 1 to 10, Comparative Examples 1 to 5]
<Production of molded products>
On the surface of the non-woven fabric (layer) obtained above, as shown in FIG. 1, the mixed yarn was arranged so that the fiber length direction was substantially parallel to the standing portion of the mold. Next, the mixed yarn was fixed (stitched) to the nonwoven fabric using a shape-retaining yarn to obtain a material.
The obtained material was heated at the temperature shown in the table from the mixed yarn side and the nonwoven fabric side for 10 minutes, transferred to a mold heated to 80° C., and pressed at a pressure of 3 MPa for 3 minutes.
As the upper mold, the one shown in the schematic diagram in FIG. 6 was used. Specifically, the upper mold (7 in FIG. 6) was a square with a side of 150 mm and provided with a concave portion 8 for forming a cross-shaped standing portion. FIG. 7 is an enlarged view of the recess 8 and shows a cross-sectional view of the erected portion. The volume of the erected portion was 7.7 cm ³ , and the opening of the erected portion (the base portion of the erected portion) was a rectangle with sides of 4 mm×150 mm and an area of 6 cm ² . The volume of the entire molding was 53 cm ² .
A press plate was used as the lower die.

<Confirmation of melting ratio>
The melted proportions of the nonwoven fabric (layer), mixed yarn and shape-retaining yarn were measured according to the following method.
<<Nonwoven fabric (layer), melting ratio of mixed yarn>>
Each site was embedded with epoxy resin, cut in an arbitrary direction, the cross section was polished, and the cross section of the region without shape-retaining threads was photographed using an ultra-depth color 3D profilometry microscope. A region composed of residual resin fibers and molten resin was selected from the cross-sectional view, and the melted ratio was calculated.
<<Proportion of melted shape-retaining yarn>>
The specimen surfaces before and after molding were photographed using an ultra-depth color 3D profilometry microscope. From the images, the amount of shape-retaining threads exposed on the surface before molding and the amount of unmelted shape-retaining threads exposed on the surface after molding were selected, and the melted ratio was calculated. This was done for each of the shape-retaining yarns on the non-woven fabric (layer) surface and the shape-retaining yarns on the mixed yarn surface.

<Height of standing part of molded product>
The height of the standing portion of the molded product was measured using an ultra-depth color 3D shape measuring microscope. The height of the standing portion was defined as the highest portion in the direction perpendicular to the average plane of the opening of the molded product.

<Molded product strength>
As shown in FIG. 8(a), a precision universal testing machine 10 (manufactured by Instron, product number: 5967) was used to set a support jig (also called an anvil) 11 having a length of 150 mm with a distance between fulcrums of 64 mm. As shown in FIG. The molded product 13 was placed at 45 degrees with respect to the length direction, and the bending strength was measured at a speed of 1 mm/min. The bending strength was evaluated as follows in comparison with the flexural strength when the non-woven fabric (layer) alone was molded in the same manner without using mixed yarns or shape-retaining yarns.
A: 2 times or more B: 1.5 times or more and less than 2 times C: 0 times or more and less than 1.5 times

<void>
The molded product was cut, the cross section was polished, and the cross section was photographed with an ultra-deep color 3D shape measuring microscope. Voids were selected and the void ratio in the molded product was calculated.

<Strength of standing part>
The erected portion was pinched with a jig (a pair of 3 mm x 3 mm rubber + screws), and was bent in a 90-degree direction at a speed of 1 mm/min using a tensile tester Strograph EII manufactured by Toyo Seiki.
A: Very good (the jig came off after exhibiting elasticity, and the standing part was not damaged)
B: Fairly good (broken after exhibiting certain elasticity)
C: Not so good but practical level (broken immediately after starting measurement)
D: Not applicable to any of the above A to D

As is clear from the above results, the molded articles obtained by the manufacturing method of the present invention had standing portions corresponding to the shape of the mold (Examples 1 to 10). In addition, the strength of the molded article obtained was excellent, and voids were few.
On the other hand, the molded articles obtained by the manufacturing methods of the comparative examples were inferior in molded article strength, and the mixed yarn could not be kept in a layer (nonwoven fabric) (Comparative Examples 1 to 5).

1 Layer such as nonwoven fabric 2 Mixed yarn 3 Thermoplastic resin fiber (B3) (shape retaining yarn)
4 Lower mold 5 Upper mold 6 Standing part 7 Mold 8 Recess 10 Precision universal testing machine 11 Support jig 12 Compression jig 13 Molded product

Claims (12)

a layer in which reinforcing fibers (A1) and thermoplastic resin fibers (B1) are randomly dispersed;
A material containing mixed yarn composed of continuous reinforcing fibers (A2) and thermoplastic resin fibers (B2),
With respect to a material in which the mixed yarn is arranged on the layer and the shape of the mixed yarn is retained by the thermoplastic resin fibers (B3),
Heating the material from the layer side at a temperature equal to or lower than the melting point of the thermoplastic resin fiber (B3), and
By heating the material from the shape-retaining side of the mixed yarn at a temperature above the melting point of the thermoplastic resin (b3) constituting the thermoplastic resin fiber (B3),
More than 99% by mass of the thermoplastic resin fiber (B1),
More than 99% by mass of the thermoplastic resin fiber (B2),
More than 50% by mass and 90% by mass or less of the portion of the thermoplastic resin fiber (B3) exposed on the side on which the mixed yarn is arranged;
A molded product having an erected portion, comprising melting more than 1% by mass and not more than 50% by mass of the portion of the thermoplastic resin fiber (B3) exposed on the layer side, and molding in the molten state. manufacturing method. The method for producing a molded article according to claim 1, wherein the layer has a density of 0.06 to 0.9 mg/mm ³ . 3. The method for producing a molded article according to claim 1, wherein the layer has a puncture strength of 0.08 to 0.9N. The melting point of the thermoplastic resin (b3) constituting the thermoplastic resin fiber (B3) is higher than the melting point of the thermoplastic resin (b2) constituting the thermoplastic resin fiber (B2), and the thermoplastic resin fiber The method for producing a molded article according to any one of claims 1 to 3, wherein the melting point of the thermoplastic resin (b1) constituting (B1) is higher than that of the thermoplastic resin (b1). A method for producing a molded article according to any one of claims 1 to 4 , wherein said layer is a non-woven fabric. 6. Manufacture of the molded product according to any one of claims 1 to 5 , wherein the impregnation rate of the thermoplastic resin fiber (B1) into the reinforcing fiber (A1) in the layer is 0.1% or more and 30% or less. Method. The method for producing a molded article according to any one of claims 1 to 6 , wherein the layer contains at least one selected from carbon fibers and glass fibers as reinforcing fibers (A1). The method for producing a molded article according to any one of claims 1 to 7 , wherein the layer contains, as the thermoplastic resin (b1), at least one thermoplastic resin selected from polyamide resins and polyolefin resins. The layer is composed of a structural unit derived from a diamine and a structural unit derived from a dicarboxylic acid as a thermoplastic resin (b1), and 50 mol% or more of the structural units derived from a diamine are polyamide resins derived from xylylenediamine. A method for producing a molded article according to any one of claims 1 to 8 , comprising The method for producing a molded article according to any one of claims 1 to 9 , wherein the mixed yarn contains at least one selected from carbon fibers and glass fibers as continuous reinforcing fibers (A2). 11. The production of the molded article according to any one of claims 1 to 10 , wherein the mixed yarn contains at least one thermoplastic resin selected from polyamide resins and polyolefin resins as the thermoplastic resin (b2). Method. The mixed yarn comprises, as the thermoplastic resin (b2), structural units derived from diamine and structural units derived from dicarboxylic acid, and 50 mol% or more of the structural units derived from diamine are derived from xylylenediamine. A method for producing a molded article according to any one of claims 1 to 11 , comprising a polyamide resin.

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