JP2021075597A - Metallic resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To obtain a resin composition having excellent impact resistance and metallically colored, without depending on the type and mode of a bright material. A metallic resin composition comprising a thermoplastic resin, a brightening material, and a hydrogenated styrene-based thermoplastic elastomer having a 300% tensile stress of more than 0 and less than 12.6 MPa. [Selection diagram] None

Description

The present invention relates to metallic resin compositions. The present invention particularly relates to a metallic resin composition having excellent impact resistance.

Conventionally, as a high-luminance resin, a metallic material-adhesive resin is produced in which a metal such as aluminum, a bright material containing glass, mica, etc., a coloring material, a stabilizer, and the like are melt-kneaded with a base resin.

In order to develop a metallic material-coated part that complies with the agreement rules related to internal protrusions, we selected a base resin with high impact resistance and colored it metallically using the above-mentioned bright material, and the impact resistance was significantly improved. There was a problem that it decreased to.

To solve such a problem, there is known a technique for solving the problem of lowering impact resistance by using a resin-attached aluminum pigment to which a predetermined resin is attached (see Patent Document 1). However, this technique requires a special resin such as a polymer containing a unit such as a carboxylic acid having a radically polymerizable double bond and a unit derived from a monomer having two or more radically polymerizable double bonds. And it was necessary to attach these to the aluminum pigment to produce a resin-attached aluminum pigment. That is, the technique disclosed in Patent Document 1 requires a special resin and a complicated process.

2018-1233328

It is desired to obtain a metallically colored resin composition having excellent impact resistance without depending on the type and mode of the bright material.

As a result of diligent studies, the present inventor has maintained sufficient impact resistance with a resin composition containing a base resin, a brightening material, and a modifier made of a predetermined resin, and metallic coloring with the brightening material is possible. He came up with the idea of obtaining a molded resin product, and completed the present invention.

That is, according to one embodiment, the present invention is a metallic resin composition, in which a thermoplastic resin, a bright material, and a hydrogenated styrene-based heat having a 300% tensile stress of more than 0 and less than 12.6 MPa. The present invention relates to a metallic resin composition containing a plastic elastomer.

According to the metallic resin composition according to the present invention, it is possible to obtain a resin molded product having a coloring effect by a bright material and impact resistance. The metallic resin composition according to the present invention is also advantageous in that a metallic colored resin molded product can be produced using any general-purpose bright material without depending on the use of a bright material of a specific type or embodiment. is there.

Hereinafter, embodiments of the present invention will be described. However, the present invention is not limited to the embodiments described below.

[Metallic resin composition]
According to one embodiment, the present invention includes a thermoplastic resin, a brightening material, and a modifier with respect to the metallic resin composition.

The thermoplastic resin is a resin that is the main component of the resin composition according to the present embodiment, and may be any thermoplastic resin. In the present specification, the thermoplastic resin is also referred to as a base resin. Thermoplastic resins include, for example, polypropylene (PP), such as homopolypropylene, polymethyl methacrylate (PMMA), polycarbonate (PC), polyamide (PA), acrylonitrile-budaziene-styrene copolymer (ABS), acrylonitrile / ethylene. Examples include, but are not limited to, propylene-diene-styrene copolymers (AES), modified resins thereof, or mixtures of two or more of these. The thermoplastic resin can be appropriately selected by those skilled in the art depending on the use of the metallic resin composition. As an example, when the metallic resin composition constitutes an automobile interior member, the thermoplastic resin includes polycarbonate (PC), polypropylene (PP), and acrylonitrile / ethylene / propylene-diene / styrene copolymer (AES). ), Polymethyl methacrylate (PMMA) and the like are preferably used. This is because it is preferable that automobile interior parts have a certain degree of rigidity, heat resistance, light resistance, and the like.

The bright material is a material that imparts brightness to the resin composition according to the present embodiment, and is preferably a material that makes the resin composition according to the present embodiment metallic. As the bright material, aluminum flakes, aluminum pigments such as vapor-deposited aluminum and colored aluminum may be used. Other pigments include interfering mica pigments, white mica pigments, bright pigments such as graphite pigments, metal oxide pigments such as titanium oxide and iron oxide, composite metal oxide pigments such as titanium yellow, carbon black, and azo pigments. Pigments, quinacridone pigments, diketopyrrolopyrrole pigments, perylene pigments, perinone pigments, benzimidazolone pigments, isoindolin pigments, isoindolinone pigments, metal chelate azo pigments, phthalocyanine pigments, indanslon Color pigments such as system pigments, dioxane pigments, and indigo pigments, and extender pigments such as clay, kaolin, barium sulfate, barium carbonate, calcium carbonate, talc, silica, and alumina white are not limited thereto.

The shape of the glittering material is not particularly limited, but may be, for example, a coin shape, a flake shape, or the like. The particle size of the bright material preferably has an average particle size of 1 to 100 μm, more preferably 5 to 50 μm, but is not limited to a specific average particle size range.

In a preferred embodiment, the glittering material is a metal capable of coloring the resin composition in silver metallic, inorganic flakes on which the metal is vapor-deposited, thermosetting resin flakes on which the metal is vapor-deposited, and more preferably an aluminum glittering material. The aluminum bright material may be any material containing an aluminum pigment, and the aluminum pigment may be used as it is, or may be a masterbatch in which the aluminum pigment is kneaded into a resin or the like.

The content of the bright material in the resin composition is, for example, 100, the mass of the base resin, regardless of whether the bright material is an aluminum bright material or a bright material containing other pigments as a main component. In the case of parts by mass, it can be 1 to 10 parts by mass, preferably 1 to 5 parts by mass, but is not limited to a specific content range.

The modifier is added to the resin composition according to the present embodiment together with the brightening material to impart impact resistance to the resin molded product obtained from the resin composition. As the modifier, a hydrogenated styrene-based thermoplastic elastomer having a 300% tensile stress of more than 0 and less than 12.6 MPa is used. The 300% tensile stress referred to here is a property of the modifier alone before being added to the resin composition, and refers to a value measured according to ISO37. The hydrogenated styrene-based thermoplastic elastomer having such physical properties exists between the base resin and a bright material such as an aluminum pigment, and when the resin composition is deformed, only the elastomer having a low elastic coefficient is deformed. It is considered that the deformation and destruction of the bright material can be suppressed and the impact resistance of the resin composition can be improved.

The 300% tensile stress of the hydrogenated styrene-based thermoplastic elastomer is more preferably more than 0 and 8.3 MPa or less, further preferably more than 0 and 6.0 MPa or less, and more than 0 and 4. It is even more preferably 4 MPa or less, and most preferably 2.5 MPa or more and 4.4 MPa or less. Such an elastomer with low stress tends to relax stress when deformed, and energy is less likely to accumulate. Therefore, it is hard to be broken even if it is greatly deformed, and it can contribute to further improvement of impact resistance.

The hydrogenated styrene-based thermoplastic elastomer also preferably has a tensile elongation of more than 460%. The tensile elongation is also a property of the modifier alone before being added to the resin composition, and refers to a value measured according to ISO37. The tensile elongation is more preferably 490% or more, and the larger the upper limit is, the better, but it can be, for example, about 1500% or less. In the resin composition, when the hydrogenated styrene-based thermoplastic elastomer is broken, it is considered that the breaking of the bright material also proceeds. Therefore, the elastomer which is hard to break due to large deformation contributes to further improvement of impact resistance. be able to.

The hydrogenated styrene-based thermoplastic elastomer may be a polymer having the above-mentioned physical properties and having a hydrogenated styrene repeating unit, and its structural characteristics are not particularly limited, but ethylene is added to styrene. , Butylene, butadiene and the like having a repeating unit structure can be preferably used.

When a hydrogenated styrene-based thermoplastic elastomer having a 300% tensile stress of more than 0 and less than 12.6 MPa is used as a modifier, the content of the modifier in the metallic resin composition is 100 mass by mass of the base resin. In the case of parts, it can be 1 to 10 parts by mass, preferably 1 to 5 parts by mass, but is not limited to a specific content range.

In addition to the thermoplastic resin (base resin), the glittering material, and the modifier, the resin composition of the present invention may contain other components as long as these characteristics are not impaired. Examples of other components include, but are not limited to, flame retardants, antioxidants, dispersants, plasticizers, stabilizers, colorants other than bright materials, and the like.

[Manufacturing method of resin composition]
Next, a method for producing the resin composition of the present invention will be described. As a method for producing a resin composition, for example, the constituent components of the composition containing pellets of a base resin, a brightening material, and a modifier are placed in one container and dry-blended, and then a twin-screw extruder or the like is used. It can be carried out by melt-kneading and pelletizing, but is not limited to a specific method.

The metallic resin composition according to the present embodiment thus obtained is not particularly limited as long as it has the specific composition described in detail above, and is in a solid state even if it is in a fluid state. It may be. The metallic resin composition has a brilliant property and also has an impact property when it is made into a solid molded product.

[Metallic resin molded product]
The metallic resin composition of the present invention can be molded into a predetermined shape to obtain a metallic resin molded product. The molding method is not particularly limited, but for example, the pelleted metallic resin composition can be injected into a mold having a desired shape which may be heated to a desired temperature for molding. In addition, molding methods such as extrusion molding, press molding, injection press molding, and blow molding are also possible.

The metallic resin molded product can be used as an impact resistant member alone or in combination with other parts or members. As an example, the impact resistant member may be an automobile interior member. Specific automobile interior components include, but are not limited to, switch bezels, navigation garnishes, audio garnishes, shift garnishes, instrument panel ornaments, door trim ornaments, and meter clusters. As another example, the impact resistant member may be a component of electrical equipment or household goods.

The metallic resin molded product according to the present embodiment has a preferable appearance due to a bright material and impact resistance by providing a specific composition in the resin composition, and can be widely used in various applications. In particular, a composition containing a bright material containing a metal or an inorganic compound and having a particle size larger than several μm or a bright material containing resin particles exhibiting brittleness has conventionally been of great concern of deterioration in impact resistance. According to the present embodiment, the resin molded product containing these bright materials is also advantageous in that it has sufficient impact resistance and a desired appearance.

Hereinafter, the present invention will be described in more detail with reference to Examples. However, the present invention is not limited to the following examples.

Metallic resin compositions of Examples and Comparative Examples were prepared. In both the compositions of Examples and Comparative Examples, a polycarbonate resin (product name: Panlite SS2525Z, manufactured by Teijin Limited) was used as the base resin, and an aluminum pigment masterbatch (product name: MHF) was used as the bright material. −A-05CB50, Nagase Sangyo Co., Ltd.) was used. The masterbatch used had specifications such that the base resin was an acrylonitrile styrene copolymer, the aluminum ratio was 50% by mass, the aluminum shape was coin-shaped, and the aluminum particle diameter was 5 μm. The amount of the bright material added is shown in Table 2 below.

As the modifier, a hydrogenated styrene-based thermoplastic elastomer manufactured by Asahi Kasei Corporation was used in both Examples 1 to 5 and Comparative Example 3. Details of the modifiers used are shown in Table 1. O. E. (Registered trademark) is a hydrogenated styrene-butadiene copolymer, Toughtech (registered trademark) M series is a hydrogenated styrene / ethylene / butylene / styrene copolymer, and Toughtech (registered trademark) H series is a modified M series. (The model numbers of Examples 4 and 5 are acid-modified). Both the tensile elongation and the 300% tensile stress are the physical characteristics of the hydrogenated styrene-based thermoplastic elastomer itself before being added to the resin composition, and are values measured in accordance with ISO37. The amount of the modifier added is shown in Table 2 below.

To prepare the metallic resin composition, a polycarbonate resin, an aluminum brightener, and a modifier are mixed, and pellets of the base resin, aluminum MB, and modifier are placed in one container and dry-blended, and then a twin-screw extruder is used. (HYPERKTX 30 SHT-HS manufactured by Kobe Steel) was melt-kneaded at a barrel temperature of 270 to 280 ° C., a rotation speed of 200 rpm, and a discharge rate of 38 kg / h, cooled in a water tank while stretching the strands, and pelletized with a pelletizer. Next, a resin molded product was obtained by injection molding at a resin temperature of 270 to 280 ° C. and a mold temperature of 80 ° C. using an ISO dumbbell test piece mold in an injection molding machine (FANUC ROBOSHOT S-2000i 100A). The Charpy impact value of the resin molded product was measured according to ISO179-1. The fracture morphology by the Charpy impact test is shown in Table 2 together with the Charpy impact value, where C is for complete fracture and P is for partial fracture. Further, both the compositions of Examples and Comparative Examples were colored in silver metallic by the aluminum brightening material, and no difference in appearance was observed.

From the results shown in Table 2 above, it was found that the impact resistance can be improved by using a hydrogenated styrene-based thermoplastic elastomer having predetermined physical properties as the modifier.

Claims (8)

A metallic resin composition containing a thermoplastic resin, a bright material, and a hydrogenated styrene-based thermoplastic elastomer having a 300% tensile stress of more than 0 and less than 12.6 MPa. The metallic resin composition according to claim 1, wherein the hydrogenated styrene-based thermoplastic elastomer has a 300% tensile stress of 2.5 MPa or more and 4.4 MPa or less. The metallic resin composition according to claim 1 or 2, wherein the hydrogenated styrene-based thermoplastic elastomer has a tensile elongation of more than 460%. The metallic resin composition according to any one of claims 1 to 3, wherein the thermoplastic resin contains polycarbonate. The metallic resin composition according to any one of claims 1 to 4, wherein the bright material contains an aluminum bright material. The metallic resin composition according to any one of claims 1 to 5, wherein the amount of the hydrogenated styrene-based thermoplastic elastomer added is 1 to 10 parts by mass with respect to 100 parts by mass of the thermoplastic resin. An impact resistant member comprising a molded product of the metallic resin composition according to any one of claims 1 to 6. The impact-resistant member according to claim 7, which is a member for an automobile interior.