JP6076664B2 - Polyamide resin composition and molded body comprising the same - Google Patents

Description

  The present invention relates to a polyamide resin composition excellent in luminance and clearness.

Generally, an interior / exterior cover of an automobile engine cover or home appliance is formed of a thermoplastic resin such as a polyamide resin. The appearance of such a resin molded product may require a metallic color tone such as steel or aluminum alloy. Particularly in recent years, there has been an increasing demand for the aesthetics of resin molded products, and there is a demand for a metallic color tone that not only has a metallic color tone but also has a glossy feeling and a high brightness. In addition, various kinds of metallic tones are required, from silver-gray to slightly whiteish grayish white. In order to satisfy such a requirement, conventionally, a so-called metallic coating method has been performed in which a paint containing a metal powder such as aluminum is applied to the surface of a resin molded product. However, since this metallic coating uses an organic solvent, there is a problem in terms of work environment. Further, the productivity is inferior and the cost is increased.
As a method for solving the above problems, a resin composition in which a thermoplastic resin such as polyamide resin is filled with glossy particles in which metal powder such as aluminum or metal such as mica, wollastonite, or glass is coated. Has been proposed.
For example, Patent Document 1 discloses a polyamide resin composition in which particles expressing a metallic color are blended with a polyamide resin in which layered silicate is uniformly dispersed at a molecular level.
Patent Document 2 discloses a polyamide resin composition containing a polyamide resin and metal flakes.

International Publication No. 99/13006 Pamphlet

Special table 2001-509524

However, there is a problem that the balance between brightness and clearness is insufficient even with the polyamide resin compositions of Patent Documents 1 and 2.
Also, when dispersing metal flakes or the like in polyamide resin, there is a method of mixing metal flakes once in high concentration in polyethylene or the like, mixing as a so-called masterbatch, or mixing metal flakes and various oil pastes. It is limited, and when organic components other than the polyamide resin are mixed, a clear feeling as a resin composition may be deteriorated or a color tone may be uneven.
An object of this invention is to provide the polyamide resin composition excellent in a brightness | luminance and a clear feeling.

The present inventors have reached the present invention as a result of intensive studies in order to solve such problems.
That is, the gist of the present invention is as follows.

(1) The polyamide resin (A) contains 100 parts by mass of the swellable layered silicate (B) 2-9 parts by mass, the vapor-deposited metal powder pigment (C) 0.5-5 parts by mass , C) is scaly, has an average particle diameter of 1 to 60 μm, and a thickness of 1 to 10 μm.
(2) The polyamide resin composition according to (1), wherein the swellable layered silicate (B) is any one selected from fluorine mica, montmorillonite, and hectorite.
(3) The polyamide resin composition according to (1) or (2), wherein the vapor-deposited metal powder pigment (C) is obtained by pulverizing a vapor-deposited metal film.
(4) The polyamide resin composition according to any one of (1) to (3), wherein the vapor-deposited metal powder pigment (C) has a scaly shape and has a thickness of 1 to 10 μm .
(5) The polyamide resin composition according to any one of (1) to (4), wherein the vapor-deposited metal powder pigment (C) has a bulk specific gravity of 0.20 g / cm ³ or less.
(6) The swellable layered silicate (B) is dispersed in the monomer component constituting the polyamide resin (A), polymerized to obtain a resin composition, and then the resin composition and the deposited metal powder pigment (C). The method for producing a polyamide resin composition according to any one of (1) to ( 5 ), wherein the mixture is melt-mixed.
(7) A molded article obtained by molding the polyamide resin according to any one of (1) to (5).
(8) The molded article according to (7), which is an automobile part or an electrical part.
(9) The vapor-deposited metal powder pigment (C) and the resin composition obtained by dispersing the swellable layered silicate (B) in the monomer component constituting the polyamide resin (A) and polymerizing the resin are obtained. The method for producing a molded article according to (7) or (8), wherein the molding is performed after being mixed and then supplied to a molding machine.

  ADVANTAGE OF THE INVENTION According to this invention, the polyamide resin composition excellent in a brightness | luminance and a clear feeling can be provided. Since the molded body obtained by molding such a polyamide resin composition can particularly enhance the metallic luster and the design, it can be suitably used as an automobile part or an electrical part.

  The polyamide resin (A) used in the present invention is not particularly limited, and various aliphatic polyamides, semi-aromatic polyamides, and aromatic polyamides can be used.

  Aliphatic polyamides include polycaproamide (nylon 6), polytetramethylene adipamide (nylon 46), polyhexamethylene adipamide (nylon 66), polycaproamide / polyhexamethylene adipamide copolymer (nylon 6) / 66), polyundecamide (nylon 11), polycaproamide / polyundecamide copolymer (nylon 6/11), polydodecamide (nylon 12), polycaproamide / polydodecamide copolymer (nylon 6/12), polyhexamethylene Examples include sebacamide (nylon 610), polyhexamethylene dodecamide (nylon 612), polyundecamethylene adipamide (nylon 116), and mixtures or copolymers thereof.

  Semi-aromatic polyamides or aromatic polyamides include polyhexamethylene isophthalamide (nylon 6I), polyhexamethylene terephthalamide (nylon 6T), polyhexamethylene terephthalamide / polyhexamethylene isophthalamide copolymer (nylon 6T / 6I), Polycaproamide / polyhexamethylene terephthalamide copolymer (nylon 6 / 6T), polycaproamide / polyhexamethylene isophthalamide copolymer (nylon 6 / 6I), polyhexamethylene adipamide / polyhexamethylene terephthalamide copolymer (nylon 66 / 6T), polyhexamethylene adipamide / polyhexamethylene isophthalamide copolymer (nylon 66 / 6I), polytrimethylhexamethylene terephthalamide Nylon TMDT), polybis (4-aminocyclohexyl) methane dodecamide (nylon PACM12), polybis (3-methyl-4-aminocyclohexyl) methane dodecamide (nylon dimethyl PACM12), polymetaxylylene adipamide (nylon MXD6), Examples include polydecamethylene terephthalamide (nylon 10T), polyundecamethylene terephthalamide (nylon 11T), and mixtures and copolymers thereof.

  The various aliphatic polyamides, semi-aromatic polyamides, and aromatic polyamides may be used alone or in combination. In the case of mixing, for example, a swelling layered silicate (B) described later is dispersed in the monomer component (ε-caprolactam) constituting nylon 6 to obtain a polymer, and then a swelling layered silicate (B ) Not containing nylon 10T can be used.

  The relative viscosity, which is an index of the molecular weight of the polyamide resin, is not particularly limited, but the relative viscosity measured under the conditions of 96% by mass concentrated sulfuric acid as a solvent at a temperature of 25 ° C. and a concentration of 1 g / dl is 1.5 to 1.5. It is preferable that it is 3.5, More preferably, it is 1.7-3.2, More preferably, it is 1.9-3.0. If the relative viscosity is less than 1.5, the strength of the resulting polyamide resin composition may be lowered. On the other hand, when the relative viscosity exceeds 3.5, the fluidity is inferior and kneading becomes difficult, and the moldability is deteriorated, so that the brightness and clearness may be inferior.

  The swellable layered silicate (B) used in the present invention may be naturally produced or artificially synthesized or modified, for example, smectite group (montmorillonite, beidellite, hectorite, soconite, etc.), vermiculite group ( Vermiculite, etc.), mica (fluorine mica, muscovite, paragonite, phlogopite, lepidrite, etc.), brittle mica (margarite, clintonite, anandite, etc.), chlorite (donbasite, sudoite, kukeite, clinochlore, chamo) In the present invention, Na-type or Li-type swellable fluorinated mica and montmorillonite are particularly preferably used.

  The swellable fluorine mica preferably used in the present invention generally has a structural formula represented by the following formula.

M _a (Mg _X Li _b ) Si ₄ O _Y F _Z
(In the formula, M represents an ion-exchangeable cation, and specific examples include sodium and lithium. A, b, X, Y, and Z each represents a coefficient, and 0 ≦ a ≦ 0.5. 0 ≦ £ b ≦ £ 0.5, 2.5 ≦ X ≦ 3, 10 ≦ Y ≦ 11, 1.0 ≦ Z ≦ 2.0)
As a method for producing such a swellable fluorine mica, for example, silicon oxide, magnesium oxide and various fluorides are mixed, and the mixture is completely melted in an electric furnace or a gas furnace at a temperature range of 1400 to 1500 ° C. In addition, a melting method in which a swellable fluorine mica crystal grows in the reaction vessel during the cooling process can be mentioned.

On the other hand, there is also a method of using talc [Mg ₃ Si ₄ O ₁₀ (OH) ₂ ] as a starting material and intercalating alkali metal ions thereto to impart swelling property to obtain a swellable fluorine mica (Japanese Patent Laid-Open No. Hei. No. 2-149415). In this method, swellable fluoromica can be obtained by heat-treating talc and alkali silicofluoride mixed at a predetermined blending ratio in a magnetic crucible at a temperature of 700 to 1200 ° C. for a short time.

  At this time, the amount of alkali silicofluoride mixed with talc is preferably in the range of 10 to 35% by mass of the entire mixture. When it is outside this range, the yield of the swellable fluorinated mica tends to decrease.

  The montmorillonite used in the present invention is represented by the following formula, and can be obtained by refining a naturally produced product using a water syrup treatment or the like.

M _a Si (Al ₂ —aMg) O ₁₀ (OH) ₂ .nH ₂ 0
(In the formula, M represents a cation such as sodium, and 0.25 ≦ a ≦ 0.6. Further, the number of water molecules bonded to the ion-exchangeable cation between layers depends on conditions such as cation species and humidity. (It is expressed as nH ₂ O in the formula)
In addition, montmorillonite is known to have isomorphic ion substitution products such as magnesia montmorillonite, iron montmorillonite, iron magnesia montmorillonite, and these may be used.

  The amount of the swellable layered silicate (B) is 1 to 10 parts by weight, preferably 2 to 9 parts by weight, and 3 to 8 parts by weight with respect to 100 parts by weight of the polyamide resin (A). It is more preferable. If it is less than 1 part by mass, the mechanical strength is impaired or the effect of improving the clear feeling is insufficient. If it exceeds 10 parts by mass, it has smoothness and unevenness in color tone, and the clearness is lowered.

  The vapor-deposited metal powder pigment (C) used in the present invention is any one or more of a group of metals consisting of aluminum, chromium, zinc, gold, silver, platinum, nickel, or an alloy using these groups of metals, or these It is a vapor-deposited metal powder pigment made of a metal made of an oxide of a group of metals or alloys thereof. Especially, the thing using aluminum is preferable at the point which the brightness improvement effect of a polyamide resin composition is excellent. The vapor-deposited metal powder pigment (C) may have a protective layer. By using such a vapor-deposited metal powder pigment (C), it is possible to impart the necessary metallic luster even when the amount of the vapor-deposited metal powder pigment (C) is small relative to the polyamide resin (A). Therefore, it is particularly preferable.

  Although the shape of the vapor-deposited metal powder pigment (C) of the present invention is not particularly limited, it is preferably flat or scaly. Conventional metal powder pigments are generally in the form of grains, and when they are observed from the side in a state where they are arranged in a plane, the surface becomes random uneven. In other words, as long as the surface is random unevenness, even if a light ray enters there, it is irregularly reflected, and it is difficult to obtain a desired metallic luster after all.

  When a scale-like metal powder pigment is used as the vapor-deposited metal powder pigment (C) of the present invention, the surface of the molded body obtained by observing it from the side in a state where it is arranged in a plane is a conventional substantially grain-shaped fine powder. Compared to the case, the state is more planar. That is, since the surface is relatively smooth, the incident light is reflected in almost the same direction when a light beam is incident thereon, and the metallic luster on the surface of the obtained molded body can be improved. In the vapor-deposited metal powder pigment (C), the vapor-deposited metal powder pigment (C) produced by a method obtained by performing aluminum vapor deposition on the base material and then pulverizing it with the base material has particularly high planarity. It can be suitably used in the invention.

Bulk density of the deposited metal powder pigment (C) is preferably at 0.25 g / cm ³ or less, it is more preferably 0.20 g / cm ³ or less, 0,15g / cm ³ or less Further preferred. When the bulk specific gravity exceeds 0.25 g / cm ³ , there is less concern about segregation and aggregation during mixing with the resin composition, so that dispersibility is improved and luminance can be increased efficiently. The bulk specific gravity can be measured according to JIS K 7365.

  The average particle diameter of the vapor-deposited metal powder pigment (C) is preferably 1 to 60 μm, more preferably 2 to 50 μm, further preferably 3 to 40 μm, and particularly preferably 4 to 30 μm. preferable. When the average particle size is less than 1 μm, it is difficult to obtain the vapor-deposited metal powder pigment itself, and even if such a vapor-deposited metal powder pigment is obtained, the effect of improving the brightness is lowered. When the average particle diameter exceeds 60 μm, handling when obtaining the polyamide resin composition becomes difficult, and it becomes difficult to carry out melt mixing while maintaining the average particle diameter of the deposited metal powder pigment as the raw material. Moreover, even if it can be melt-mixed, although the brightness | luminance of the polyamide resin composition obtained increases, the tendency to be inferior to designability increases. The average particle diameter of the vapor-deposited metal powder pigment (C) can be measured by a laser diffraction / scattering particle size distribution measuring device, for example, Microtrack 2 (manufactured by Nikkiso Co., Ltd.).

  The average thickness of the vapor-deposited metal powder pigment (C) is preferably 1 to 10 μm, more preferably 1 to 5 μm, and still more preferably 1 to 3 μm. When the average thickness is less than 1 μm, the rigidity is poor and it becomes difficult to maintain the shape when melt-mixed. Therefore, it becomes difficult to obtain sufficient glossiness in the polyamide resin composition. When the average thickness exceeds 10 μm, the dispersibility of the vapor-deposited metal powder pigment (C) is inferior, and the surface smoothness of the molded product obtained when the vapor-deposited metal powder pigment (C) overlaps results in a glossiness. It will be inferior. In addition, the average thickness of the vapor-deposited metal powder pigment (C) produced by a method obtained by performing aluminum vapor deposition on the substrate and then pulverizing it with the substrate in the vapor-deposited metal powder pigment (C) The total thickness obtained by adding the material thickness and the deposition thickness shall be indicated. The average thickness of the vapor-deposited metal powder pigment (C) can be calculated by a simple average of 50 vapor-deposited metal powder pigments measured with an electron microscope.

The aspect ratio of the vapor-deposited metal powder pigment (C) is preferably 2 to 60, more preferably 2 to 50, and further preferably 2 to 30. When the aspect ratio is less than 2, it can no longer be distinguished from the granular metal powder pigment, and the brightness of the resulting molded article surface is inferior. Those having an aspect ratio exceeding 60 are difficult to obtain industrially, and even if obtained, the dispersion stability is inferior, and the surface smoothness of the resulting molded article is impaired.
The aspect ratio of the vapor-deposited metal powder pigment (C) can be obtained by dividing the value of the average particle diameter by the average thickness value.

  The compounding quantity of vapor deposition metal powder pigment (C) is 0.5-5 mass parts with respect to 100 mass parts of polyamide resins (A). If the blending amount is less than 0.5 parts by mass, excellent luminance cannot be obtained, and if it exceeds 5 parts by mass, a clear feeling corresponding to the blending amount does not appear.

  In the present application, it is important to use a specific amount of the swellable layered silicate (B) and a specific amount of the deposited metal powder pigment (C) in combination. In order to improve the luminance of the molded article to be obtained, it is an essential requirement to use the vapor-deposited metal powder pigment (C), but the swellable layered silicate (B) is added to the vapor-deposited metal powder pigment (C). The combined use increases the effect of improving the dispersibility of the vapor-deposited metal powder pigment (C). Since the vapor-deposited metal powder pigment (C) is a scale-like metal powder pigment, it is excellent in luminance, but has a tendency to be inferior in dispersibility as compared with the conventional granular metal powder pigment. By using the swellable layered silicate (B) and the vapor-deposited metal powder pigment (C) in combination, it is possible to improve the luminance of the molded article obtained without impairing the dispersibility. Furthermore, although the reason is not well understood, there is a tendency that a clear feeling increases as the brightness of the surface of the molded body increases. Swellable layered silicate (B) enters the gaps between the vapor-deposited metal powder pigment (C) dispersed on the surface of the resulting molded article, or the swelling is dispersed at a position deeper than the vapor-deposited metal powder pigment (C) on the molded article surface. This is probably because the layered silicate (B) enhances the reflection of light or increases the reflectance of light on the surface of the molded body.

The manufacturing method of the polyamide resin composition of this invention is demonstrated. In the present invention, as a method for producing a polyamide resin composition, after obtaining a resin composition obtained by dispersing a swellable layered silicate (B) in a monomer component constituting a polyamide resin (A), a vapor deposited metal is obtained. A method of melt-mixing the powder pigment (C) can be preferably mentioned. Although it is possible to melt-knead the swellable layered silicate (B) and the vapor-deposited metal powder pigment (C) at once or in two separate steps to the polyamide resin (A), the polyamide resin composition of the present invention In order to further increase the brightness of the molded product obtained from the product, a resin composition obtained by dispersing the swellable layered silicate (B) in the monomer component constituting the polyamide resin (A) was obtained. Thereafter, a method of melt-mixing the deposited metal powder pigment (C) is most preferable. In addition, when performing melt mixing of the vapor-deposited metal powder pigment (C), a known melt-kneading extruder can be used, but in order to suppress crushing or breakage due to kneading of the vapor-deposited metal powder pigment (C) as much as possible, The screw of the extruder is preferably a single screw rather than a twin screw. As a method for supplying the vapor-deposited metal powder pigment (C), the resin composition and the vapor-deposited metal powder pigment (C) can be mixed and then charged from the main hopper, but extrusion is performed to suppress crushing or breakage as much as possible. It can also be supplied from the middle of the machine with a side feeder. In addition, when supplying, it is preferable to supply more downstream of the extruder. Even if the resin composition and the vapor-deposited metal powder pigment (C) are not necessarily sufficiently melt-kneaded, they can be mixed within a range that does not hinder the work in the subsequent injection molding process, for example. If necessary, after the resin composition and the vapor-deposited metal powder pigment (C) are dry blended without performing melt kneading, they can be directly supplied to an injection molding machine to perform injection molding. When the bulk specific gravity of the vapor-deposited metal powder pigment (C) to be used is 0.25 g / cm ³ or less, the workability during mixing such as the vapor-deposited metal powder pigment being scattered may be reduced. Workability can be improved by performing injection molding after spreading a certain amount of vapor-deposited metal powder pigment on the resin composition using a suitable spreading agent such as paraffin. The vapor-deposited metal powder pigment (C) is brittle with respect to external stress, and it is important to improve the luminance of the obtained polyamide resin composition that the screw shear stress during melt-kneading is not applied as much as possible. .

  The method for dispersing the swellable layered silicate (B) at the molecular level in the polyamide 6 resin is not particularly limited, but the method is a method in which the swellable layered silicate (B) swollen and expanded between layers is mixed with a polyamide monomer and polymerized. Or a method of blending the swellable layered silicate (B) previously treated with the interlayer treating agent by melt kneading, but other blending that can uniformly disperse the swellable layered silicate (B) in the polyamide resin If it is a method, methods other than the above can also be selected.

  As a method for polymerizing a swellable layered silicate (B) that has been swollen and expanded between layers with a polyamide monomer, a predetermined amount of monomer is charged into an autoclave in the presence of an appropriately selected swellable layered silicate (B). Then, an initiator such as water may be used and the melt polycondensation method may be performed within a range of a temperature of 240 to 300 ° C., a pressure of 0.2 to 3 MPa, and a time of 1 to 15 hours. When nylon 6 is used as the resin matrix, it is preferable to polymerize at a temperature of 250 to 280 ° C., a pressure of 0.5 to 2 MPa, and a range of 3 to 5 hours.

  Moreover, in order to remove the polyamide monomer remaining in the polyamide resin after polymerization, it is preferable to scour the polyamide resin pellets with hot water. In this case, the treatment is preferably performed in hot water at 90 to 100 ° C. for 8 hours or more.

  As a method of blending the swellable lamellar silicate (B) previously treated with the interlayer treating agent by melt kneading, the polyamide resin and the swellable lamellar layer are heated by using a uniaxial kneader to a temperature higher than the melting point of the polyamide resin It can be obtained by melt-kneading the silicate (B). At that time, the swellable layered silicate (B) is preferably subjected to interlayer treatment with an interlayer treatment agent such as a quaternary ammonium salt in order to improve dispersion during kneading, and does not inhibit adhesion with the polyamide resin. Any material can be used as appropriate.

  As a method of melt-kneading the vapor-deposited metal powder pigment (C) with respect to the above-mentioned “polyamide resin in which the swellable layered silicate (B) is dispersed”, a biaxial kneader is used to heat it above the melting point of the polyamide resin. And a method of melt-kneading the polyamide resin and the vapor-deposited metal powder pigment (C).

  A pigment, a heat stabilizer, an antioxidant, a weathering agent, a plasticizer, a lubricant, a release agent, an antistatic agent, etc. may be added to the polyamide resin composition of the present invention as long as the properties are not significantly impaired. it can. Examples of heat stabilizers and antioxidants include hindered phenols, hindered amines, sulfur compounds, copper compounds, alkali metal halides, and the like. In addition, the method of mixing these with the resin composition of this invention is not specifically limited. Moreover, in order to assist flame retardancy in particular, a condensed phosphate ester, polyphosphoric acid, a nitrogen compound flame retardant, or the like may be added.

  The polyamide resin composition of the present invention can be formed into various molded products by molding methods such as injection molding, blow molding, extrusion molding, inflation molding, and vacuum molding, pressure molding, and vacuum / pressure molding after sheet processing. Among these, it is preferable to use an injection molding method, and in addition to a general injection molding method, gas injection molding, injection press molding, and the like can be employed. If an example of the injection molding conditions suitable for the polyamide resin composition of this invention is given, cylinder temperature will be more than melting | fusing point or flow start temperature of a resin composition, Preferably it is 190-270 degreeC, Moreover, metal mold temperature is resin composition. (Melting point -20 ° C.) or less. If the molding temperature is too low, the moldability may become unstable, for example, a short may occur in the molded product, or the glossiness of the surface of the resulting molded body may be lost. On the other hand, when the molding temperature is too high, the polyamide resin composition is decomposed, and the strength of the resulting molded product may be reduced, or the glossiness may be reduced.

The molded product obtained from the polyamide resin composition of the present invention can enhance the brightness and clearness of the molded product obtained by the injection molding method. The clear feeling is an indicator of whether the resin layer is sufficiently formed on the surface of the plate-like molded body or whether the flatness and the surface smoothness are sufficient. If the resin layer is not sufficiently formed, the planar smoothness is inferior and the surface becomes rough and rough. When there is a clear feeling, the glossy surface can be seen with a depth as if it had a transparent layer on the surface. This state is similar to, for example, a state in which an image is projected onto the plating layer through the glass in a mirror having a plating layer formed on the back surface of the glass plate.
In the present invention, the brightness and clearness of the resulting molded article are sufficient, so that the metallic luster due to the vapor-deposited metal powder pigment (C) can be increased, and the glossiness is deep, so that the design is enhanced. Can do. Moreover, brightness and clearness can be further improved by adjusting various conditions during injection molding in a well-balanced manner. At that time, brightness and clearness can be adjusted by appropriately setting the resin temperature, injection speed, injection pressure, and mold temperature. The resin temperature, the injection speed, and the injection pressure are the flowability of the molten polyamide resin composition in the mold, and further the swellable layered silicate (B) in the polyamide resin composition, vapor deposited metal powder pigment Since it affects the dispersibility of (C), it is necessary to set conditions carefully. As an example of the conditions, when the injection speed is high, the orientation of the vapor-deposited metal powder pigment is disturbed and the brightness tends to decrease. Therefore, the injection speed should be low to medium.

  Specific examples of the molded body using the polyamide resin composition of the present invention include various parts and casings around personal computers, cellular phone parts and casings, and other resin parts for electrical appliances such as OA equipment parts, bumpers, and instruments. Examples include resin parts for automobiles such as panels, console boxes, garnishes, door trims, ceilings, floors, and panels around the engine. Moreover, it can also be set as a film, a sheet | seat, a hollow molded product, etc.

  EXAMPLES Hereinafter, although an Example demonstrates this invention concretely, this invention is not limited by these Examples.

1. Evaluation method Using the obtained resin composition, using an injection molding machine (EC-100II type manufactured by Toshiba Machine Co., Ltd.), resin temperature 260 ° C., mold temperature 100 ° C., injection speed 100 mm / s, injection pressure 100 MPa, holding pressure Injection molding was performed at 30 MPa and a cooling time of 10 seconds to obtain a plate-like molded body having a length of 90 mm × width of 50 mm × thickness of 2 mm.
The following evaluation was performed on the obtained plate-like molded body.

(1) Smoothness The smoothness of the plate-like molded product was judged visually.
◯: Mold transfer is sufficient and smooth.
X: The float or sink of the pigment contained in the molded body surface is observed.

(2) Spots of color tone The plate-like molded product was observed with the naked eye, and the dispersion state of the contained pigment was evaluated.
○: Uniformly dispersed.
Δ: There is some unevenness in the dispersion, and light and shade is felt.
X: Not only is there light and dark, but there is agglomeration of the pigment locally.

(3) Surface glossiness Based on JIS Z8741, the surface glossiness of the plate-shaped molded body was measured using a gloss meter (Nippon Denshoku Co., Ltd. gloss meter VG7000 type). The glossiness is preferably 90% or more practically.

(4) Luminance The luminance was sensory-evaluated with the naked eye by observing from a direction of an angle of 45 ° with the normal line of the plate-shaped molded body under a fluorescent lamp having an illuminance of 1000 Lx. The evaluation result is preferably 3 or 4.
5: It has a glare feeling but is excessive.
4: Although it has a glare feeling, it is slightly excessive.
3: It has a moderate glare feeling.
2: The metal-specific brightness is insufficient.
1: Does not have metal-specific shine.

(5) Clear feeling The plate-shaped molded body was observed from various angles under a fluorescent lamp with an illuminance of 1000 Lx, and the clear feeling was subjected to sensory evaluation with the naked eye.
○: When a fluorescent lamp is copied onto the surface of the plate-shaped molded body, the shape of the fluorescent lamp can be seen as it is.
Δ: When a fluorescent lamp is projected on the surface of the plate-shaped molded body, the shape of the fluorescent lamp can be seen, but the fluorescent lamp line appears blurred.
X: The shape of the fluorescent lamp cannot be recognized even if the fluorescent lamp is copied onto the surface of the plate-like molded body.

(6) Comprehensive judgment (designability)
A comprehensive judgment was made based on the above evaluation. ◎ or ◯ is preferable.
A: Brightness and clearness are sufficient, and metallic luster and design are sufficient.
○: Practically sufficient, but lacks brightness and clearness.
Δ: Brightness and clearness are not sufficient.
X: There is a problem in flatness and smoothness.

2. Raw material (1) Polyamide resin (a-1): Polyamide 6 (A1030BRT manufactured by Unitika)
(A-2): Polyamide 66 (E2000 manufactured by Unitika)
(A-3): Polyamide 10T (XecoT manufactured by Unitika)

(2) Swellable layered silicate. (B-1): Fluorine mica (ME-100 manufactured by Coop Chemical Co.)
(B-2): Hectorite (BentoneHC manufactured by Elementis Specialties)
(B-3): Organically treated fluorinated mica (MEE manufactured by Corp Chemical; ME-100 treated with quaternary ammonium salt)

(3) Metallic pigment (c-1): Vapor-deposited aluminum powder pigment (Elegio Silver # 325, manufactured by Oike Kogyo Co., Ltd.) Average particle size 35 μm, thickness 2-3 μm, bulk specific gravity 0.15 g / cm ³
(C-2): Vapor-deposited aluminum powder pigment (Elgi neo Silver # 500, manufactured by Oike Kogyo Co., Ltd.) Average particle size 15 μm, thickness 2 to 3 μm, bulk specific gravity 0.15 g / cm ³
-(C-3): Vapor-deposited aluminum powder pigment (Elji neo Silver # 100, manufactured by Oike Kogyo Co., Ltd.) Average particle size 115 μm, thickness 2 to 3 μm, bulk specific gravity 0.15 g / cm ³
(C-4): Iron oxide pigment (AM-200 manufactured by Titanium Industry Co., Ltd.) Average particle size 13 μm, average thickness 0.3 μm, bulk specific gravity 0,35 g / cm ³ , a mixture of aluminum oxide and iron oxide.
-(C-5): Aluminum powder masterbatch (NME U20TZ manufactured by Toyo Aluminum Co., Ltd.) A product obtained by kneading 70% by mass of aluminum powder into polyethylene. Contains aluminum powder; average particle size 20μm
(C-6): Aluminum pigment paste (Alpaste SCR-5070 manufactured by Toyo Aluminum Co., Ltd.), average particle size 12 μm, thickness 0.57 μm, aspect ratio 21, solid content 75%
-(C-7): Pearl pigment (Iriodin # 100 manufactured by Merck Japan Co., Ltd.) Mica surface having an average particle diameter of 20 μm and titanium coated by 0.3 μm.

Production Example 1
After blending 0.4 part by mass of phosphorous acid, 5 parts by mass of swellable layered silicate (b-1) and 5 parts by mass of water with respect to 100 parts by mass of ε-caprolactam, the mixture was stirred at 80 ° C. for 1 hour. The mixture was stirred at 260 ° C. and 0.7 MPa for 1 hour, and then stirred at 260 ° C. and normal pressure for 1 hour to carry out polymerization to obtain a polyamide resin (P-1) containing 5.2% by mass of fluorine mica. . The results are shown in Table 1.

Production Example 2
After blending 0.4 parts by mass of phosphorous acid, 5 parts by mass of swellable layered silicate (b-2), and 5 parts by mass of water with respect to 100 parts by mass of ε-caprolactam, the mixture was stirred at 80 ° C. for 1 hour. The mixture was stirred at 260 ° C. and 0.7 MPa for 1 hour, and then stirred at 260 ° C. and normal pressure for 1 hour to carry out polymerization to obtain a polyamide resin (P-2) containing 4.7% by mass of hectorite. . The results are shown in Table 1.

Production Example 3
100 parts by mass of the polyamide resin (a-1) and 5 parts by mass of the organically treated swellable layered silicate (b-3) are mixed together and melt-kneaded using a twin screw extruder to obtain a polyamide resin (P-3). ) The melt kneading was performed at a resin temperature of 260 ° C., a screw rotation of 200 rpm, and a discharge rate of 30 kg / h. The results are shown in Table 1.

Production Example 4
100 parts by mass of the polyamide resin (a-2) and 5 parts by mass of the organically treated swellable layered silicate (b-3) are mixed together and melt-kneaded using a twin screw extruder to obtain a polyamide resin (P-4). ) The melt kneading was performed at a resin temperature of 280 ° C., a screw rotation of 200 rpm, and a discharge rate of 30 kg / h. The results are shown in Table 1.

Production Example 5
100 parts by mass of polyamide resin (a-3) and 5 parts by mass of organically treated swellable layered silicate (b-3) are mixed together, melt-kneaded using a twin screw extruder, and polyamide resin (P-5) ) The melt kneading was performed at a resin temperature of 335 ° C., a screw rotation of 200 rpm, and a discharge rate of 30 kg / h. The results are shown in Table 1.

Production Example 6
After blending 0.4 parts by mass of phosphorous acid, 1 part by mass of swellable layered silicate (b-1) and 5 parts by mass of water with respect to 100 parts by mass of ε-caprolactam, the mixture was stirred at 80 ° C. for 1 hour. The mixture was stirred at 260 ° C. and 0.7 MPa for 1 hour, and then stirred at 260 ° C. and normal pressure for 1 hour to conduct polymerization to obtain a polyamide resin (P-6) containing 1.1% by mass of fluorine mica. . The results are shown in Table 1.

Production Example 7
After blending 0.4 parts by mass of phosphorous acid, 8 parts by mass of the swellable layered silicate (b-1) and 5 parts by mass of water with respect to 100 parts by mass of ε-caprolactam, the mixture was stirred at 80 ° C. for 1 hour. The mixture was stirred at 260 ° C. and 0.7 MPa for 1 hour, and then stirred at 260 ° C. and normal pressure for 1 hour to conduct polymerization to obtain a polyamide resin (P-7) containing 8.1% by mass of fluorine mica. . The results are shown in Table 1.

Production Example 8
After blending 0.4 part by mass of phosphorous acid, 11 parts by mass of swellable layered silicate (b-1) and 5 parts by mass of water with respect to 100 parts by mass of ε-caprolactam, the mixture was stirred at 80 ° C. for 1 hour. The mixture was stirred at 260 ° C. and 0.7 MPa for 1 hour, and then stirred at 260 ° C. and normal pressure for 1 hour to conduct polymerization to obtain a polyamide resin (P-8) containing 10.8% by mass of fluorine mica. . The results are shown in Table 1.

Production Example 9
With respect to 100 parts by mass of ε-caprolactam, 0.4 part by mass of phosphorous acid, 0.5 part by mass of the swellable layered silicate (b-1) and 5 parts by mass of water are blended and stirred at 80 ° C. for 1 hour. After that, the mixture was stirred at 260 ° C. and 0.7 MPa for 1 hour, and then stirred at 260 ° C. and normal pressure for 1 hour to conduct polymerization to obtain a polyamide resin (P-9) containing 0.5% by mass of fluorine mica. Obtained. The results are shown in Table 1.

Example 1
105.5 parts by mass of the swellable layered silicate salt-containing polyamide resin (P-1) obtained in Production Example 1 and 1 part by mass of the vapor-deposited metal powder pigment (c-1) were mixed together, and a single screw extruder was used. It was charged from the main hopper, melted and kneaded, extruded into a strand from a die, cooled, and pelletized to obtain polyamide resin composition pellets. The melt kneading was performed at a resin temperature of 260 ° C., a screw rotation of 200 rpm, and a discharge rate of 30 kg / h. The obtained polyamide resin composition was used for injection molding, and various evaluations were performed using the obtained plate-like molded product. The results are shown in Table 2.

Examples 2-6, 9 , 10
A polyamide resin composition was obtained and subjected to various evaluations in the same manner as in Example 1 except that the composition described in Table 2 was followed. The results are shown in Table 2.

Example 7
104.7 parts by mass of the swellable layered silicate-containing polyamide resin (P-4) obtained in Production Example 4 and 1 part by mass of the vapor-deposited metal powder pigment (c-1) were mixed together, and the main of the single screw extruder It was charged from a hopper, melted and kneaded, extruded into a strand from a die, cooled, and pelletized to obtain polyamide resin composition pellets. The melt kneading was performed at a resin temperature of 280 ° C., a screw rotation of 200 rpm, and a discharge rate of 30 kg / h. The obtained polyamide resin composition was used for injection molding, and various evaluations were performed using the obtained plate-like molded product. The results are shown in Table 2.

Example 8
104.7 parts by mass of the swellable layered silicate-containing polyamide resin (P-5) obtained in Production Example 5 and 1 part by mass of the vapor-deposited metal powder pigment (c-1) were mixed together, and the main of the single screw extruder It was charged from a hopper, melted and kneaded, extruded into a strand from a die, cooled, and pelletized to obtain polyamide resin composition pellets. Melt kneading was performed at a resin temperature of 335 ° C., a screw rotation of 200 rpm, and a discharge rate of 30 kg / h. The obtained polyamide resin composition was used for injection molding, and various evaluations were performed using the obtained plate-like molded product. The results are shown in Table 2.

Example 11
A polyamide resin composition was obtained and subjected to various evaluations in the same manner as in Example 1 except that a twin screw extruder was used instead of the single screw extruder. The results are shown in Table 3.

Example 12
Without melting and kneading 105.5 parts by mass of the swellable layered silicate-containing polyamide resin (P-1) obtained in Production Example 1 and 1 part by mass of the vapor-deposited metal powder pigment (c-1) After being mixed together, the mixture was directly put into an injection molding machine, injection molding was performed, and various evaluations were performed using the obtained plate-like molded bodies. The results are shown in Table 3.

Comparative Examples 1, 2, 5-8
A polyamide resin composition was obtained and various evaluations were performed in the same manner as in Example 1 except that the composition described in Table 3 was followed. The results are shown in Table 3.

Comparative Example 3
Using the swellable layered silicate-containing polyamide resin (P-9), a polyamide resin composition was obtained and subjected to various evaluations in the same manner as in Example 1 except that the formulation shown in Table 3 was followed. The results are shown in Table 3.

Comparative Example 4
Using the swellable layered silicate-containing polyamide resin (P-8), a polyamide resin composition was obtained and subjected to various evaluations in the same manner as in Example 1 except that the formulation shown in Table 3 was followed. The results are shown in Table 3.

Examples 1-12, because in accordance with the formulation of the present application a predetermined evaluation result, the luminance high, no unevenness, there is a deep and there is a clear feeling, had sufficient metallic.
The following examples had the following tendencies. In Reference Example 1, the blending of the swellable layered silicate was in a predetermined range, but the clear feeling was slightly lowered because it was in the vicinity of the lower limit. Reference Example 2 used a vapor-deposited metal powder pigment having a relatively large average particle size, so that the glittering characteristic peculiar to metallic luster increased, but the color tone and clearness slightly decreased. In Example 11, since kneading was performed using a twin-screw extruder, a tendency for luminance to decrease was observed. In Example 12 , since molding was performed without kneading the vapor-deposited metal powder pigment, the surface glossiness and the brightness tended to improve.

  Since the compounding of the vapor deposition metal powder pigment exceeded the upper limit value in Comparative Example 1, the color tone was uneven and there was no clear feeling.

  In Comparative Example 2, since the blended vapor-deposited metal powder pigment was less than the lower limit, the brightness and clearness were insufficient.

  In Comparative Example 3, since the blending of the swellable layered silicate was less than the lower limit, the improvement in clearness, which is a synergistic effect with the blended metal powder pigment, was insufficient.

  In Comparative Example 4, since the blending of the swellable layered silicate exceeded the upper limit, there was an aggregate of the swellable layered silicate, the flatness and smoothness were poor, and there was no brightness and clearness.

  Since the comparative example 5 used the metallic pigment which is not a vapor deposition metal powder pigment, the clear feeling was inadequate.

  Since the comparative example 6 used the metallic pigment which is not a vapor deposition metal powder pigment, the clear feeling was inadequate. Moreover, since there was a mixture of polyethylene due to the metallic pigment used, there was a patch of color.

  Since the comparative example 7 used the metallic pigment which is not a vapor deposition metal powder pigment, the clear feeling was inadequate. Moreover, since there was oil contamination due to the metallic pigment used, there was unevenness in color.

Since the comparative example 8 used the metallic pigment which is not a vapor deposition metal powder pigment, the brightness | luminance was insufficient. In addition, color spots occurred.

Claims (9)

The amount of the swellable layered silicate (B) 2 to 10 parts by mass and the vapor-deposited metal powder pigment (C) 0.5 to 5 parts by mass with respect to 100 parts by mass of the polyamide resin (A ), A polyamide resin composition having an average particle diameter of 1 to 60 μm.   2. The polyamide resin composition according to claim 1, wherein the swellable layered silicate (B) is any one selected from fluorine mica, montmorillonite, and hectorite.   The polyamide resin composition according to claim 1 or 2, wherein the vapor-deposited metal powder pigment (C) is obtained by pulverizing a vapor-deposited metal film. 4. The polyamide resin composition according to claim 1, wherein the vapor-deposited metal powder pigment (C) is scaly and has a thickness of 1 to 10 [mu] m. 5. The polyamide resin composition according to claim 1, wherein the vapor-deposited metal powder pigment (C) has a bulk specific gravity of 0.20 g / cm ³ or less. After the swellable layered silicate (B) is dispersed in the monomer component constituting the polyamide resin (A) and polymerized to obtain a resin composition, the resin composition and the deposited metal powder pigment (C) are melt mixed. The manufacturing method of the polyamide resin composition in any one of Claims 1-5 characterized by the above-mentioned.   The molded object formed by shape | molding the polyamide resin in any one of Claims 1-5.   The molded article according to claim 7, which is an automobile part or an electrical part. After mixing the swellable layered silicate (B) with the monomer component constituting the polyamide resin (A) and mixing the vapor-deposited metal powder pigment (C) without melting the resin composition obtained by polymerization. The method for producing a molded body according to claim 7 or 8, wherein the molding is performed by supplying the molding machine.