JP6979639B2 - Manufacturing method of molded products - Google Patents

Description

The present invention relates to a method for producing a molded product.

Molded products used for automobile parts, computer housings, etc. include, for example, a molded insert material made of a fiber-reinforced composite material containing reinforced fibers and a thermoplastic resin, and the thermoplastic resin is injection-molded and integrated. The molded products mentioned above are widely used. As a method for manufacturing the molded product, for example, after the insert material is shaped into a desired shape by compression molding or the like, the shaped insert material is placed in a mold for injection molding to perform injection molding. The method can be mentioned. However, this method is costly because it is necessary to separately shape the insert material in advance and then perform injection molding.
Therefore, a molding method has been proposed in which shaping of the insert material and injection molding are performed with the same mold. For example, the insert material containing carbon fiber and the thermoplastic resin is heat-compressed and shaped by the upper mold and the lower mold, and after the thermoplastic resin is solidified, the upper mold and the lower mold are slightly separated from each other to form a gap. A method of obtaining a molded product by injecting a thermoplastic resin and molding it can be mentioned (Patent Document 1).
However, in the molded product obtained by the method, the adhesive strength of the boundary surface between the portion formed by the insert material and the portion formed by injection molding becomes insufficient, and peeling may occur at the boundary surface. be.
As a method for improving the adhesive strength of the boundary surface between the insert material portion and the injection molded portion, a method of injection molding a thermoplastic resin on the surface of the insert material via an adhesive layer has been proposed (Patent Documents 2 and 3). ).
However, even in the molded product obtained by this method, the adhesive strength at the interface between the insert material portion and the injection molded portion may not be sufficient, or when a reactive adhesive layer is used, the adhesive layer may be used. There were some parts that were inferior in productivity, such as it took time for the adhesive material to be formed to exert its adhesive strength, or injection molding had to be performed immediately after the adhesive layer was applied.

Japanese Unexamined Patent Publication No. 2013-2106039 International Publication No. 2014/11501 Japanese Unexamined Patent Publication No. 2016-187875

INDUSTRIAL APPLICABILITY The present invention provides a molded product in which a thermoplastic resin is injection-molded into a shaped insert material and integrated, and which has excellent adhesive strength at the interface between the insert material portion and the injection-molded portion. With the goal. Another object of the present invention is to provide a method for manufacturing a molded product having excellent adhesive strength at the boundary surface between the insert material portion and the injection molded portion, which can be manufactured with high productivity and low cost.

As a result of diligent studies to solve the above problems, it was found that the adhesive strength of the interface between the insert material portion and the injection molded portion can be improved by allowing nanofillers such as carbon nanotubes to exist between the insert material and the injection molded portion. We have found and completed the present invention. That is, the gist of the present invention lies in the following (1) to (12).
(1) It has a layer (A) made of a thermoplastic resin (y1) and a reinforcing fiber (f1), and a layer (B) made of a resin composition (X), and is between the layer (A) and the layer (B). A molded product in which carbon nanotubes (c) are present.
(2) A layer (A') composed of a thermoplastic resin (y1') and reinforcing fibers (f1'), and a layer (B') composed of a resin composition (X') containing carbon nanotubes (c') are formed. A molded product having a layer (A') and a layer (B') adjacent to each other.
(3) In the mold, the insert material (I) containing the thermoplastic resin (y) and the resin composition (Z) containing the thermoplastic resin (b) are integrally molded to form a molded product. It ’s a manufacturing method.
The nanofiller (d) is placed on a part of the surface of the insert material (I), and the nanofiller (d) is placed.
A method for manufacturing a molded product, in which the resin composition (Z) is supplied into the mold by injection molding with the insert material (I) arranged in the mold and integrally molded.
(4) The nanofiller (d) is arranged on a part of the surface of the insert material (I) by laminating the layer containing the nanofiller (d) on the surface of the insert material (I). The method for manufacturing a molded product according to 3).
(5) After laminating the layer containing the nanofiller (d) on the surface of the insert material (I), the layer containing the nanofiller (d) and the insert material (I) are integrated by welding. The method for producing a molded product according to (3) or (4) above, wherein the integrated product is placed in a mold.
(6) In the mold, the layer containing the nanofiller (d) is laminated on the surface of the insert material (I), and the layer containing the nanofiller (d) and the insert in the mold. The method for producing a molded product according to (3) or (4) above, wherein the material (I) is integrated.
(7) In the mold, the insert material (I) containing the thermoplastic resin (y) and the resin composition (Z) containing the thermoplastic resin (b) are integrally molded to form a molded product. It ’s a manufacturing method.
After the insert material (I) heated to the softening temperature of the thermoplastic resin (y) or higher is placed in the mold, the resin composition (Z') containing the nanofiller (d) is placed. A method for manufacturing a molded product that is supplied into a mold by injection molding and integrated.
(8) After arranging the insert material (I) heated to a temperature equal to or higher than the softening temperature of the thermoplastic resin (y) in the mold, the resin composition (Z) or the resin composition (Z') is placed. The method for manufacturing a molded product according to any one of claims 3 to 7, wherein the molded product is supplied and integrated.
(9) The insert heated in the mold to a temperature equal to or higher than the softening temperature of the thermoplastic resin (y) before supplying the resin composition (Z) or the resin composition (Z') into the mold. The manufacturing method according to (8) above, wherein the insert material (I) is molded by a mold clamping press in a state where the material (I) is arranged.
(10) The resin composition (Z) or the resin composition (Z') is placed in a mold with the insert material (I) heated to a temperature equal to or higher than the softening temperature of the thermoplastic resin (y). The method for producing a molded product according to (8) above, wherein the insert material (I) is integrated while being molded by performing mold clamping after or while supplying the insert material (I).
(11) The method for producing a molded product according to any one of claims 3 to 10, wherein the insert material (I) contains reinforcing fibers.
(12) The method for producing a molded product according to any one of claims 3 to 11, wherein the nanofiller (d) is a carbon nanotube (c'').

The molded product of the present invention is a molded product in which a thermoplastic resin is injection-molded into a shaped insert material and is integrated, and has excellent adhesive strength at the interface between the insert material portion and the injection-molded portion. Further, it is possible to manufacture a molded product having excellent adhesive strength at the boundary surface between the insert material portion and the injection molded portion with high productivity and low cost.

[Molded product]
Hereinafter, embodiments for carrying out the molded product of the present invention will be described.
[First Embodiment of Molded Product]
The first embodiment of the molded product of the present invention has a layer (A) made of a thermoplastic resin (y1) and a reinforcing fiber (f1), and a layer (B) made of a resin composition (X), and has a layer (B). It is a molded product in which carbon nanotubes (c) are present between A) and layer (B).

<Layer (A)>
The layer (A) is composed of a thermoplastic resin (y1) and reinforcing fibers (f1). The layer (A) corresponds to the insert material portion of the molded product of the present invention. The thickness of the layer (A) is not particularly limited, and is preferably 0.1 mm to 20 mm, more preferably 0.2 mm to 10 mm, still more preferably 0.3 mm to 5 mm. When the thickness of the layer (A) is at least the above lower limit value, it is easy to obtain a molded product having sufficient mechanical properties. When the thickness of the layer (A) is not more than the upper limit value, it is easy to shape it into a complicated shape such as a three-dimensional shape, and it is possible to achieve both lightness and lightness.
The content of the reinforcing fiber (f1) in the layer (A) is preferably 10 to 65% by volume, more preferably 15 to 55% by volume, still more preferably 20 to 45% by volume in terms of fiber volume content (Vf). When Vf is at least the lower limit value, it is easy to obtain a molded product having sufficient mechanical properties. If Vf is not more than the upper limit value, it is easy to shape into a complicated shape such as a three-dimensional shape.
The layer (A) contains flame retardants, weather resistance improvers, antioxidants, heat stabilizers, ultraviolet absorbers, plasticizers, lubricants, colorants, compatibilizers, conductive fillers, etc., depending on the required characteristics. Additives may be blended.

<Thermoplastic resin (y1)>
The thermoplastic resin (y1) is not particularly limited, and is, for example, a polyamide resin (nylon 6, nylon 66, nylon 12, nylon MXD6, etc.), a polyolefin resin (low density polyethylene, high density polyethylene, polypropylene, etc.), a modified polyolefin. Resin (modified polypropylene resin, etc.), polyester resin (polyethylene terephthalate, polybutylene terephthalate, etc.), polycarbonate resin, polyamideimide resin, polyphenylene oxide resin, polysulfone resin, polyethersulfone resin, polyetheretherketone resin, polyetherimide resin, Examples thereof include polystyrene resin, ABS resin, polyphenylene sulfide resin, liquid crystal polyester resin, copolymer of acrylonitrile and styrene, and copolymer of nylon 6 and nylon 66. Examples of the modified polyolefin resin include resins obtained by modifying the polyolefin resin with an acid such as maleic acid. Polyamide resin, polyolefin resin, modified polyolefin resin, polyester resin, and polycarbonate resin are preferable from the viewpoint of improving adhesiveness by carbon nanotubes. As the thermoplastic resin (y1), one type may be used alone, or two or more types may be used in combination.

<Reinforcing fiber (f1)>
The reinforcing fiber (f1) is not particularly limited, and for example, an inorganic fiber, an organic fiber, a metal fiber, or a reinforcing fiber having a hybrid structure in which these are combined can be used.
Examples of the inorganic fiber include carbon fiber, graphite fiber, silicon carbide fiber, alumina fiber, tungsten carbide fiber, boron fiber, glass fiber and the like. Examples of the organic fiber include aramid fiber, high-density polyethylene fiber, other general nylon fiber, polyester fiber and the like. Examples of the metal fiber include fibers such as stainless steel and iron, and carbon fibers coated with metal may also be used. Among these, carbon fiber is preferable in consideration of mechanical properties such as strength of the molded body.
The reinforcing fiber (f1) may be a continuous fiber or a discontinuous fiber. Since continuous fibers have excellent mechanical properties and discontinuous fibers have excellent moldability, they can be used properly as needed, but discontinuous fibers are preferable from the viewpoint of the balance between mechanical properties and moldability. The form of the reinforcing fiber base material forming the prepreg includes a form in which a large number of continuous fibers are arranged in one direction to form a UD sheet (unidirectional sheet), a form in which continuous fibers are woven into a cloth material (woven fabric), and these. Examples thereof include a form in which a notch is made in the reinforcing fiber of the above to form a discontinuous fiber, a form in which a non-woven fabric composed of the discontinuous fiber is formed, and a form in which the discontinuous fiber is kneaded and dispersed in a resin by a twin-screw extruder. Examples of the weaving method of the cloth material include plain weave, twill weave, satin weave, and triaxial weave.
The number average fiber length of the reinforcing fiber (f1) is preferably 1 to 100 mm, more preferably 3 to 70 mm, further preferably 5 to 50 mm, particularly preferably 10 to 50 mm, and most preferably 10 to 35 mm. When the number average fiber length of the reinforcing fibers (f1) is at least the above lower limit value, it is easy to obtain a molded product having sufficient mechanical properties. When the number average fiber length of the reinforcing fibers (f1) is not more than the upper limit value, it is easy to shape the fiber-reinforced composite material into a complicated shape such as a three-dimensional shape.

<Layer (B)>
The layer (B) is made of the resin composition (X) and corresponds to the injection material portion of the molded product of the present invention.
The thickness of the layer (B) is not particularly limited, and is preferably 0.5 mm to 20 mm, more preferably 0.7 mm to 10 mm, still more preferably 1 mm to 5 mm. When the thickness of the layer (B) is at least the above lower limit value, it is possible to achieve both sufficient mechanical properties and easy shaping into a complicated shape such as a three-dimensional shape. When the thickness of the layer (B) is not more than the upper limit value, both lightness and ease of shaping into a complicated shape such as a three-dimensional shape can be achieved.
From the viewpoint of improving the rigidity of the molded product of the present invention, it is preferable that the layer (B) has a rib portion.

<Resin composition (X)>
The resin composition (X) is not particularly limited, and examples thereof include the same thermoplastic resins as those mentioned in the thermoplastic resin (y1). As the resin composition (X), one kind may be used alone, or two or more kinds may be used in combination. When a thermoplastic resin is used as the resin composition (X), the resin composition (X) has a higher adhesive strength between the layer (A) and the layer (B) in the obtained molded product and is moldable. Is preferably the same type of resin as the thermoplastic resin (y1).
The resin composition (X) contains a reinforcing fiber, a flame retardant, a weather resistance improving agent, an antioxidant, a heat stabilizer, an ultraviolet absorber, a plasticizer, a lubricant, a coloring agent, and the like, depending on the required characteristics of the desired molded product. It may contain additives such as a compatibilizer and a conductive filler.
It may be formed only of the resin composition (X) and the thermoplastic resin, or may be formed of the thermoplastic resin and the reinforcing fibers (f2) having a number average fiber length of less than 1 mm. Examples of the type of the reinforcing fiber (f2) include the same types as those mentioned in the reinforcing fiber (f1), and carbon fiber is preferable.
The fiber mass content of the reinforcing fiber (f2) in the resin composition (X) is preferably 40% by mass or less, more preferably 30% by mass or less, still more preferably 25% by mass or less. When the fiber mass content of the reinforcing fiber (f2) is not more than the upper limit value, the material is easily filled in the resin composition (X) and is excellent in moldability. The fiber mass content of the reinforcing fiber (f2) in the resin composition (X) is preferably 10% by mass or more, more preferably 15% by mass or more, from the viewpoint that sufficient strength of the rib portion can be easily obtained.

<Carbon nanotube (c)>
Examples of the carbon nanotube (c) include fullerenes, metal-encapsulated fullerenes, onion-shaped fullerenes, carbon nanotubes, carbon nanohorns, carbon nanofibers, peapods, gas phase growth carbon (VGCF), graphite, graphene, carbon nanoparticles and ketjen. Black is mentioned. These can be used alone or in combination of two or more.
Examples of the shape of the carbon nanotube (c) include single-walled carbon nanotubes, multi-walled carbon nanotubes in which several layers are concentrically stacked, and single-walled carbon nanotubes or multi-walled carbon nanotubes formed into a coil shape.
Further, as the carbon nanotube (c), for example, a cylindrical one in which the graphite-like carbon atom surface of a layer having a thickness of several atoms is rounded has a single layer or a plurality of nested structures, and the outer diameter on the order of nanometers is extremely small. Substances can be used. Further, as the carbon nanotube (c), for example, a carbon nanohorn having a shape in which one side of the carbon nanotube is closed or a cup-shaped nanocarbon material having a hole in the head thereof can be used.
As the carbon nanotube (c), those crushed using a ball-type kneading device such as a ball mill, a vibration mill, a sand mill, a roll mill, etc., or those cut short by chemical or physical treatment shall be used, if necessary. Can be done.
Examples of the method for producing the carbon nanotube (c) include a catalytic hydrogen reduction method for carbon dioxide, an arc discharge method, a laser evaporation method, a CVD method, a vapor phase growth method, a vapor phase flow method, and carbon monoxide at high temperature and high pressure. The HiPco method of reacting with an iron catalyst and growing in a gas phase can be mentioned.
As the carbon nanotube (c), single-walled carbon nanotubes and multi-walled carbon nanotubes obtained by the above-mentioned production method are preferable.
In the first embodiment of the molded product of the present invention, the carbon nanotubes (c) are present between the layers (A) and the layers (B), but the thickness of the layer in which the carbon nanotubes (c) are present is 0. It is preferably 0.01 mm to 0.5 mm. When the thickness of the layer in which the carbon nanotube (c) is present is within the above range, it is easy to obtain a molded product having excellent adhesiveness between the layer (A) and the layer (B).
The carbon nanotubes (c) are preferably present between the layers (A) and the layers (B) in a state of being dispersed in the thermoplastic resin. The type of the thermoplastic resin is not particularly limited, and examples thereof include the same types as the thermoplastic resin mentioned in the thermoplastic resin (y1), and one type may be used alone or two or more types may be used. It may be used together. The thermoplastic resin (y1) into which the carbon nanotube (c) is dispersed is a thermoplastic resin in which the carbon nanotube (c) is dispersed from the viewpoint of higher adhesive strength between the layer (A) and the layer (B) and the formability in the obtained molded product. ) And / or the same type of resin as the thermoplastic resin used in the resin composition (X) is preferable.
The content of the carbon nanotubes (c) when the carbon nanotubes (c) are dispersed in the thermoplastic resin is preferably 0.1% by mass to 5% by mass. When the content of the carbon nanotube (c) is at least the above lower limit value, it is easy to obtain a molded product having excellent adhesiveness between the layer (A) and the layer (B). When the content of the carbon nanotube (c) is high, the mechanical properties of the aggregated portion of the carbon nanotubes deteriorate, but when it is below the above upper limit, the aggregation of the carbon nanotubes can be suppressed, and a molded product having excellent mechanical properties can be obtained. Easy to obtain.

[Second Embodiment of Molded Product]
A second embodiment of the molded article of the present invention is a resin composition (X') containing a layer (A') composed of a thermoplastic resin (y1') and reinforcing fibers (f1'), and carbon nanotubes (c'). It is a molded product having a layer (B') composed of), and the layer (A') and the layer (B') are adjacent to each other.
The layer (A') consists of a thermoplastic resin (y1') and reinforcing fibers (f1').
The layer (A') of the second embodiment of the molded product of the present invention has the same preferable thickness as the layer (A) for the same reason as the layer (A) of the first embodiment.
The content of the reinforcing fiber (f1') in the layer (A') is also in the same preferable range for the same reason as the content of the reinforcing fiber (f1) in the layer (A) of the first embodiment.
The thermoplastic resin (y1') is not particularly limited, and examples thereof include the same thermoplastic resin (y1) as that of the first embodiment.
The reinforcing fiber (f1') is not particularly limited, and examples thereof include the same reinforcing fiber (f1) as that of the first embodiment.
The layer (B') of the second embodiment of the molded product of the present invention has the same preferable thickness as the layer (B) for the same reason as the layer (B) of the first embodiment.
The resin composition (X') of the second embodiment of the molded article of the present invention contains carbon nanotubes (c'). It is the same as the resin composition (X) of the first embodiment of the molded product of the present invention except that the resin composition (X') contains carbon nanotubes (c').
The content of the carbon nanotubes (c') in the resin composition (X') is preferably 0.1% by mass to 5% by mass. When the content of the carbon nanotube (c') is at least the above lower limit value, it is easy to obtain a molded product having excellent adhesiveness between the layer (A') and the layer (B'). When the content of carbon nanotubes (c') is high, the mechanical properties of the aggregated portion of carbon nanotubes deteriorate, but when it is below the above upper limit, the aggregation of carbon nanotubes can be suppressed and the molded product has excellent mechanical properties. Is easy to obtain.
The carbon nanotube (c') is not particularly limited, and examples thereof include the same carbon nanotubes (c) as those of the first embodiment.

[Manufacturing method of molded product]
Hereinafter, a form of a method for manufacturing a molded product of the present invention will be described.
[First Embodiment of Manufacturing Method of Molded Product]
In the first embodiment of the method for producing a molded product of the present invention, an insert material (I) containing a thermoplastic resin (y) and a resin composition (Z) containing a thermoplastic resin (b) are contained in a mold. ) Is integrally molded to manufacture a molded product. The nanofiller (d) is placed on a part of the surface of the insert material (I), and the insert material (I) is placed in a mold. By supplying the resin composition (Z) into a mold by injection molding and molding the resin composition (Z), the insert material portion made of the insert material (I) and the injection molded portion made of the resin composition (Z) can be formed. Is an integrated method for manufacturing a molded product.
As a method of arranging the nanofiller (d) on a part of the surface of the insert material (I), a method of laminating a layer containing the nanofiller (d) on the surface of the insert material (I) is preferable. The layer containing the nanofiller (d) may be in the form of a film, a plate, a liquid, a semi-solid, or a particle. Of these, the film form is preferable.
As the layer containing the nanofiller (d), it is preferable that the nanofiller (d) is dispersed in the thermoplastic resin.
The type of the thermoplastic resin is not particularly limited, and examples thereof include the same thermoplastic resins as those mentioned in the thermoplastic resin (y) described later, and one type may be used alone or two types may be used. The above may be used together. From the viewpoint of higher adhesive strength between the insert material portion and the injection material portion in the obtained molded product and the formability, the thermoplastic resin in which the nanofiller (d) is dispersed includes the thermoplastic resin (y) and / Or it is preferably a resin of the same type as the thermoplastic resin used in the resin composition (Z).
The thickness of the layer containing the nanofiller (d) is preferably 0.01 mm to 0.5 mm. When the thickness of the layer in which the nanofiller (d) is present is within the above range, it is easy to obtain a molded product having excellent adhesiveness between the layer (A) and the layer (B).

In the first embodiment of the method for producing a molded product of the present invention, when the insert material (I) is placed in the mold, the layer containing the nanofiller (d) and the insert material (I) are used. It is classified into method (i) and method (ii) according to the difference in the adhesive state of.
Method (i): After laminating the layer containing the nanofiller (d) on the surface of the insert material (I), the layer containing the nanofiller (d) and the insert material (I) are integrated by welding. After that, a method of arranging this integrated product in the mold.
Method (ii): In the mold, the layer containing the nanofiller (d) is laminated on the surface of the insert material (I), and the layer containing the nanofiller (d) is formed in the mold. A method of integrating the insert material (I).

(Method (i))
In the method (i), the layer containing the nanofiller (d) is welded to the surface of the insert material (I), so that the layer containing the nanofiller (d) is incorporated into the surface of the insert material (I). This union is placed in the mold after it is in the open state.
The welding method is not particularly limited, and examples thereof include a method of welding by heating to a temperature equal to or higher than the softening point temperature of the thermoplastic resin (y), which includes a heating press, energization heating, IR heating, IH heating, and ultrasonic waves. Examples include welding, vibration welding, and the like. Of these, a heating press is preferable.

(Method (ii))
In the method (ii), the layer containing the nanofiller (d) is laminated on the surface of the insert material (I) in the mold, and the layer containing the nanofiller (d) is laminated in the mold. And the insert material (I) are integrated. As a method of integrating the layer containing the nanofiller (d) and the insert material (I) in the mold, in addition to the welding method described in the method (i), the resin in a molten state in the mold. A method of welding by heat supply by supplying the composition (Z) can also be mentioned.
In the method (ii), IR heating is preferable for the layer containing the nanofiller (d) from the viewpoint of the adhesiveness of the insert material (I) and the manufacturing cost.

<The resin composition (Z)>
Examples of the resin composition (Z) of the first embodiment of the method for producing the molded product include the same resin composition (X) as the resin composition (X) of the first embodiment of the molded product of the present invention, which are preferable ranges and reasons. Is the same.

[Second Embodiment of Manufacturing Method of Molded Product]
A second embodiment of the method for producing a molded product of the present invention is a resin composition (Z) containing an insert material (I) containing a thermoplastic resin (y) and a thermoplastic resin (b) in a mold. ) Is integrally molded to manufacture a molded product, and after the insert material (I) heated to a temperature equal to or higher than the softening temperature of the thermoplastic resin (y) is placed in the mold. This is a method for producing a molded product in which the resin composition (Z') containing the nanofiller (d) is supplied into a mold by injection molding and integrated.

<The resin composition (Z')>
The resin composition (Z') of the second embodiment of the method for producing a molded product of the present invention contains a nanofiller (d). Examples thereof include the same as the resin composition (Z) of the first embodiment of the method for producing a molded product of the present invention, except that the nanofiller (d) is contained.
The content of the nanofiller (d) in the resin composition (Z') is preferably 0.1% by mass to 5% by mass. When the content of the nanofiller (d) is at least the above lower limit value, it is easy to obtain a molded product having excellent adhesiveness between the insert material (I) and the resin composition (Z'). When the content of the nanofiller (d) is high, the mechanical properties of the aggregated portion of the nanofiller (d) deteriorate, but when it is equal to or less than the upper limit, the aggregation of the nanofiller (d) can be suppressed and the mechanical properties It is easy to obtain excellent molded products.

Hereinafter, common parts of the first embodiment and the second embodiment of the method for manufacturing a molded product will be described.
In the production method of the present invention, when the insert material (I) is placed in the mold, it is preferable to place the insert material (I) in a state of being heated to a temperature equal to or higher than the softening temperature of the thermoplastic resin (y). Here, arranging the insert material (I) in a state of being heated to a temperature higher than the softening temperature of the thermoplastic resin (y) means that the insert material (I) is placed in a state of being heated to a temperature higher than the softening temperature of the thermoplastic resin (y) in advance. ) May be placed in the mold after being heated, or the insert material (I) may be placed in the mold and then heated to a temperature higher than the softening temperature of the thermoplastic resin (y). Examples of the heating method include heating press, energization heating, IR heating, IH heating, ultrasonic welding, vibration welding, and the like. Of these, IR heating is preferable.
It is preferable to heat the insert material (I) to a temperature higher than the softening temperature of the thermoplastic resin (y) because the adhesiveness between the insert material (I) and the injection-molded portion is improved. Further, it is preferable to heat the insert material (I) to a temperature equal to or higher than the softening temperature of the thermoplastic resin (y) so that the insert material can be molded by mold clamping.
The manufacturing method of the present invention is further classified into the following methods (1) and (2) depending on the timing of closing the mold.
Method (1): A method of closing the mold after supplying the thermoplastic resin (Z) or the thermoplastic resin (Z') into the mold.
Method (2): A method of closing a mold while supplying a thermoplastic resin (Z) or a thermoplastic resin (Z') into the mold.

(Method (1))
In the method (1), the molten thermoplastic resin (Z) or the thermoplastic resin (Z') is supplied onto the insert material (I) containing the thermoplastic resin (y) in the mold, and then the gold is used. The mold is closed and the insert material is molded while being shaped. Then, after the thermoplastic resin (y) and the thermoplastic resin (Z) or the thermoplastic resin (Z') are solidified, the mold is opened and the molded product is taken out. In the present invention, the molten thermoplastic resin (Z) or the thermoplastic resin (Z') is supplied in a state where the insert material (I) is heated to a temperature equal to or higher than the softening temperature of the thermoplastic resin (y).
In the method (1), the material insert material (I) is heated when the molten thermoplastic resin (Z) or the thermoplastic resin (Z') is supplied, so that the adhesive strength of the nanofiller (d) is increased. It is fully exhibited, and the adhesive strength of the boundary surface between the insert material portion and the injection molded portion of the obtained molded product is increased.
When the temperature of the insert material (I) when the thermoplastic resin (Z) or the thermoplastic resin (Z') is supplied is T (° C.) and the softening temperature of the thermoplastic resin (y) is Ty (° C.). The relationship between the temperature T and the softening temperature Ty is Ty ≦ T, preferably Ty + 10 (° C.) ≦ T ≦ Ty + 150 (° C.), and more preferably Ty + 30 (° C.) ≦ T ≦ Ty + 100 (° C.). When the temperature T is at least the lower limit value, a molded product having high adhesive strength at the boundary surface between the insert material portion and the injection molded portion can be obtained, and the molding time is shortened. If the temperature T is too high, it takes a long time for the thermoplastic resin (y) in the insert material (I) to solidify after molding, and the productivity is lowered, or the thermoplasticity in the insert material (I) is reduced. Problems such as thermal decomposition of the resin (y) may occur. However, if the temperature T is not more than the upper limit, there is no problem in the time until the thermoplastic resin (y) in the insert material (I) solidifies after molding, and the thermoplastic resin in the insert material (I) is not a problem. It is easy to suppress the thermal decomposition of (y).
The softening temperature of the thermoplastic resin is the melting temperature (melting point) of the thermoplastic resin when the thermoplastic resin is a crystalline resin, and the glass transition temperature of the thermoplastic resin when the thermoplastic resin is an amorphous resin. , These mean the values measured by the differential scanning calorimetry (DSC) method according to JIS K7121.
The mold temperature at the time of mold clamping is preferably 5 ° C. or higher, more preferably 15 ° C. or higher, lower than the temperature at which the softening temperature of the thermoplastic resin (A) and the thermoplastic resin (B) is lower. As a result, the thermoplastic resin (A) and the thermoplastic resin (B) in the molded product are sufficiently cooled and solidified, so that the mold can be easily removed from the mold.

(Method (2))
In the method (2), gold is supplied while supplying the molten thermoplastic resin (Z) or the thermoplastic resin (Z') onto the insert material (I) containing the thermoplastic resin (y) in the mold. The mold is closed and the insert material is molded while being shaped. In the method (2), instead of closing the mold after supplying the molten thermoplastic resin (Z) or the thermoplastic resin (Z'), the molten thermoplastic resin (Z) or the thermoplastic resin (Z') is used. ) Is closed, the same as the method (1).

<Insert material (I)>
The insert material (I) of the production method of the present invention contains a thermoplastic resin (y). Examples of the type of the thermoplastic resin (y) include the same types as the thermoplastic resin (y1) of the first embodiment of the molded product of the present invention, and the preferable range and the reason are also the same.
The insert material (I) of the production method of the present invention is a reinforcing fiber, a flame retardant, a weather resistance improving agent, an antioxidant, a heat stabilizer, an ultraviolet absorber, a plasticizer, depending on the required characteristics of the target molded product. It may contain additives such as lubricants, colorants, compatibilizers, and conductive fillers. Above all, it is preferable that it contains reinforcing fibers. The type and form of the reinforcing fiber, the number average fiber length, and the preferable range thereof and the reason thereof are the same as those of the reinforcing fiber (f1) of the first embodiment of the molded product of the present invention.
The preferable content of the reinforcing fiber in the insert material (I) and the reason thereof are the same as the content of the reinforcing fiber (f1) in the layer (A) in the first embodiment of the molded product of the present invention.
The preferable thickness of the insert material (I) and the reason thereof are the same as the thickness of the layer (A) in the first embodiment of the molded product of the present invention.
<Nanofiller (d)>
The nanofiller (d) may be a filler having a short side length of 0.1 nm to 500 nm, and may be, for example, carbon nanotubes (c ″), cellulose nanoparticles, titanium oxide nanoparticles, gold nanoparticles, or silver nanoparticles. Examples thereof include particles, iron oxide magnetic nanoparticles, boron nitride nanotubes, and fluorescent silica nanobeads. Of these, carbon nanotubes (c'') are preferable.
The carbon nanotube (c'') is the same as the carbon nanotube (c) of the first embodiment of the molded product of the present invention.

Hereinafter, the present invention will be described in detail by way of examples, but the present invention is not limited by the following description.

[Production Example 1: Fabrication of Carbon Nanotube Dispersed Polypropylene Film]
Polypropylene resin (Prime Polymer J108M, MFR 45 g / 10 min (230 ° C)) and carbon nanotubes (NANOCYL NC7000, average diameter 9.5 nm, average length 1.5 μm) manufactured by Nanosil Co., Ltd. have a mass ratio of 99: 1. A carbon nanotube / polypropylene compound having a carbon nanotube content of 1.0% by mass was produced by twin-screw extrusion and kneading using a twin-screw extruder manufactured by Coperion Co., Ltd. A film having a thickness of 200 μm was prepared by passing a film having a thickness of 200 μm from the obtained carbon nanotube / polypropylene compound through a nip roll.

[Manufacturing Example 2: Fabrication of Insert Material Containing Carbon Nanotubes]
Seven carbon fiber / polypropylene UD prepregs (manufactured by Mitsubishi Rayon, PPUD-34, fiber volume content (Vf) 34% by volume, thickness 120 μm), carbon fiber fiber axis direction is 0 ° / 90 ° in plan view After laminating so as to be / 0 ° / 90 ° / 0 ° / 90 ° / 0 °, the carbon nanotube-dispersed polypropylene film produced in Production Example 1 was further laminated on it to prepare a 120 mm × 70 mm laminate. did. The obtained laminate was integrated by heat welding at a press load of 5 kN and a heating temperature of 200 ° C. using a press machine (TAIYO, servo press machine), and the rectangular carbon nanotubes having a plan view shape of 120 mm × 70 mm were integrated. The contained insert material was prepared.

[Manufacturing Example 3: Fabrication of Carbon Nanotube-Free Insert Material]
A carbon nanotube-free insert material was produced in the same manner as in Production Example 2 except that the carbon nanotube-dispersed polypropylene film was not laminated.

[Evaluation of interfacial adhesiveness]
A test having a length of 25.4 mm and a width of 6.3 mm was cut out from the obtained molded product, and a short beam three-point bending test conforming to ASTM D2344 was carried out. In the load-displacement curve at the time of the test, the shear strength F was calculated from the following equation (1) with the load at the first yield point as Pm, and this was taken as the interfacial shear strength (adhesive strength).
F = ((3 × Pm × t) / (b × h ² )) × ((1-t) / h) ... Equation (1)
F: Shear strength (MPa)
Pm: Yield load at the first yield point on the load-deflection curve (N)
b: Width of test piece (mm)
h: Test piece thickness (mm)
t: Insert material thickness (mm)

(Example 1)
After arranging the carbon nanotube-containing insert material obtained in Production Example 1 in the mold, a carbon nanotube-dispersed polypropylene of the carbon nanotube-containing insert material was used by an injection molding machine (PLASTER ET-40V manufactured by Toyo Kikai Kinzoku Co., Ltd.). Polypropylene resin (Novatec PP MA04A, MFR 40g / 10min (230 ° C)) manufactured by Nippon Polypro Co., Ltd. is applied to the surface on which the film is laminated at an injection speed of 100 mm / sec, a holding pressure of 80 MPa, a cylinder temperature of 240 ° C, and a mold temperature of 70 ° C. By injecting under the conditions, a 2.4 mm thick molded product in which the insert material and the injection resin were integrated was obtained.
The interfacial shear strength (adhesive strength) between the insert material portion and the injection resin portion of the obtained molded product was 10.6 MPa.

(Comparative Example 1)
A 2.4 mm thick molded product was obtained in the same manner as in Example 1 except that the carbon nanotube-free insert material obtained in Production Example 2 was used instead of the carbon nanotube-containing insert material obtained in Production Example 1. rice field.
The interfacial shear strength (adhesive strength) between the insert material portion and the injection resin portion of the obtained molded product was 6.8 MPa, and the adhesive strength was insufficient.

Claims (9)

A method for manufacturing a molded product by integrally molding an insert material (I) containing a thermoplastic resin (y) and a resin composition (Z) containing a thermoplastic resin (b) in a mold. And
The nanofiller (d) is arranged on a part of the surface of the insert material (I), and the nanofiller (d) is a carbon nanotube (c ″).
A method for manufacturing a molded product, in which the resin composition (Z) is supplied into the mold by injection molding with the insert material (I) arranged in the mold and integrally molded. Placing a nanofiller (d) in a part of the nanofiller wherein the layer insert material containing (d) (I) the insert member by laminating the surface of (I) the surface of, claim 1 Manufacturing method of molded products. The layer containing the nanofiller (d) is laminated on the surface of the insert material (I), and then the layer containing the nanofiller (d) and the insert material (I) are integrated by welding, and then this integration is performed. The method for producing a molded product according to claim 1 or 2 , wherein the compound is placed in a mold. In the mold, the layer containing the nanofiller (d) is laminated on the surface of the insert material (I), and in the mold, the layer containing the nanofiller (d) and the insert material (I) are laminated. ) Is integrated, the method for manufacturing a molded product according to claim 1 or 2. A method for manufacturing a molded product by integrally molding an insert material (I) containing a thermoplastic resin (y) and a resin composition (Z) containing a thermoplastic resin (b) in a mold. And
After the insert material (I) heated to the softening temperature of the thermoplastic resin (y) or higher is placed in the mold, the resin composition (Z') containing the nanofiller (d) is placed. A method for manufacturing a molded product, which is supplied into a mold by injection molding and integrated, and the nanofiller (d) is a carbon nanotube (c ″). After arranging the insert material (I) heated to a temperature higher than the softening temperature of the thermoplastic resin (y) in the mold, the resin composition (Z) or the resin composition (Z') is supplied. The method for manufacturing a molded product according to any one of claims 1 to 5 , which is integrated. Before supplying the resin composition (Z) or the resin composition (Z') into the mold, the insert material (I) heated in the mold to a temperature equal to or higher than the softening temperature of the thermoplastic resin (y). The manufacturing method according to claim 6 , wherein the insert material (I) is molded by a mold clamping press in a state where) is arranged. The resin composition (Z) or the resin composition (Z') was supplied in a state where the insert material (I) heated to a temperature higher than the softening temperature of the thermoplastic resin (y) was arranged in the mold. The method for manufacturing a molded product according to claim 6 , wherein the mold is fastened afterwards or while being supplied, and the insert material (I) is integrated while being molded. The method for producing a molded product according to any one of claims 1 to 8 , wherein the insert material (I) contains reinforcing fibers.