JP2018193518A - Polyamide resin composition and molding obtained by molding the same - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a polyamide resin composition which is excellent in decorativeness and can obtain a molded product having a soft color like pearl. SOLUTION: 100 parts by mass of polyamide resin (A), 1.0 to 10.0 parts by mass of swellable layered silicate (B), 0.04 to 0.5 parts by mass of aluminum powder (C), and pearl. It contains 0.7 to 5.0 parts by mass of the pigment (D), the average particle size of the aluminum (C) is 10 to 35 μm, and the mass ratio of the aluminum powder (C) to the pearl pigment (D) [( C) / (D)] is 0.01 to 0.7, which is a polyamide resin composition. [Selection diagram] None

Description

  The present invention relates to a polyamide resin composition which is excellent in decorating properties and can obtain a molded article having a soft hue such as pearl.

  In recent years, pearl-like decorated products have been used for vehicle-related parts such as automobiles and motorcycles, electrical equipment such as OA equipment and television, cameras, cosmetic containers and the like.

  The product includes a resin composition in which a thermoplastic resin such as a polyamide resin is mixed with metallic powder such as aluminum, or glossy particles whose surfaces are coated with metal such as mica, wollastonite, and glass. Yes. For example, Patent Document 1 discloses a polyamide resin composition in which particles expressing a metallic color and a mica pearl pigment are blended with a polyamide resin in which layered silicate is uniformly dispersed at a molecular level. .

International Publication No. 99/013006 Pamphlet

  However, the molded product obtained from the polyamide resin composition described in Patent Document 1 has a problem that it has a strong metallic tone and a soft color such as pearl is not sufficient.

  This invention solves the said problem, Comprising: It aims at providing the polyamide resin composition which is excellent in decorating property and can obtain the molded object of soft hues like a pearl.

In order to solve such problems, the present inventor, as a result of intensive research, blended a specific amount of layered silicate, aluminum powder and pearl pigment, and the average particle diameter of aluminum in a specific range, The inventors have found that the above object can be achieved by setting the ratio of the aluminum powder and the pearl pigment to a specific range, and have reached the present invention.
That is, the gist of the present invention is as follows.

(1) 100 parts by mass of polyamide resin (A), 1.0 to 10.0 parts by mass of swellable layered silicate (B), 0.04 to 0.5 parts by mass of aluminum powder (C), and pearl pigment (D) 0.7 to 5.0 parts by mass, the average particle diameter of aluminum (C) is 10 to 35 μm, and the mass ratio of aluminum powder (C) to pearl pigment (D) [(C ) / (D)] is 0.01 to 0.70.
(2) The polyamide resin composition according to (1), wherein the polyamide resin (A) is a mixture of polyamide 6 and polyamide 11 or polyamide 12.
(3) The polyamide resin composition according to (2), wherein the ratio of polyamide 6 in the mixture of polyamide 6 and polyamide 11 or polyamide 12 is 70 to 90% by mass.
(4) The polyamide resin composition according to any one of (1) to (3), wherein the swellable layered silicate (B) is at least one selected from fluorine mica, montmorillonite, and hectorite. object.
(5) A molded article comprising the polyamide resin composition according to any one of (1) to (4).

  According to the polyamide resin composition of the present invention, it is possible to obtain a molded article having excellent decorating properties and a soft hue such as pearl.

  In the present invention, the pearl tone means a flop index of 1.0 to 6.0 and a hue angle range of 25 ° or more. The flop index is a relative change in brightness seen between the vicinity of the reflection angle and the vicinity of the receding angle. The greater the amount of change, the greater the change in brightness depending on the viewing angle. If the flop index is larger than 6.0, the metallic tone becomes strong and the pearl tone does not develop, which is not preferable. If the flop index is less than 1.0, the color change depending on the viewing angle is not felt. It is not preferable. The flop index is preferably from 1.0 to 3.0, more preferably from 1.3 to 2.0, since the pearly tone becomes higher. Further, the hue angle range is an angle range in which the hue can be changed, and becomes a larger value as the angle range in which the hue changes is wider. The hue angle range is preferably 100 ° or more, and more preferably 130 ° or more, since the pearly hue becomes higher.

  The polyamide resin composition of the present invention contains a polyamide resin (A), a swellable layered silicate (B), an aluminum powder (C), and a pearl pigment (D).

  Examples of the polyamide resin (A) include polyamide 6, polyamide 46, polyamide 66, polyamide 11, polyamide 12, polyamide 610, polyamide 612, polyamide 116, a mixture thereof, and a copolymer thereof. Among these, since the range of hue angles is wide, polyamide 6 alone, a mixture of polyamide 6 and polyamide 11, or a mixture of polyamide 6 and polyamide 12 is preferable, and a mixture of polyamide 6 and polyamide 11 or polyamide 6 and polyamide 12 is preferred. The mixture of is more preferable. The content of polyamide 6 in the polyamide resin (A) of the mixture is preferably 60 to 100% by mass, and more preferably 70 to 90% by mass.

  The relative viscosity of the polyamide resin (A) is preferably 1.5 to 3.5 under the conditions of a temperature of 25 ° C. and a concentration of 1 g / dL using 96% by mass concentrated sulfuric acid as a solvent. 2 is more preferable, and 1.9 to 3.0 is even more preferable. If the relative viscosity is less than 1.5, the toughness of the molded article of the polyamide resin composition obtained may be inferior. On the other hand, if the relative viscosity exceeds 3.5, the fluidity may be inferior and kneading may become difficult, or the moldability may be reduced.

  The polyamide resin composition of the present invention needs to contain a swellable layered silicate (B), an aluminum powder (C), and a pearl pigment (D) in order to obtain a pearly hue.

Examples of the swellable layered silicate (B) used in the present invention include a smectite group such as montmorillonite, beidellite, hectorite, and soconite, a vermiculite group such as vermiculite, a fluorite mica, a muscovite, a paragonite, a phlogopite, and a lipidolite. Examples include brittle mica such as mica, margarite, clintnite, and anandite, and chlorite such as donbasite, sudite, kukeite, clinochlore, chamonite, and nimite. In the present invention, swellable fluorine mica, montmorillonite, and hectorite are particularly preferably used. These may be used alone or in combination of two or more. The swellable layered silicate may be naturally produced or artificially synthesized or modified.

The swellable fluorine mica 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 examples thereof include sodium and lithium. A, b, X, Y, and Z represent coefficients, respectively, 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 the swellable fluorine mica, for example, silicon oxide, magnesium oxide and various fluorides are mixed, and the mixture is completely melted in a temperature range of 1400-1500 ° C. in an electric furnace or a gas furnace, and then cooled. A melting method in which swellable fluorine mica is crystal-grown in a reaction vessel during the process can be mentioned. Further, there is a method of using talc [Mg ₃ Si ₄ O ₁₀ (OH) ₂ ] as a starting material and intercalating alkali metal ions to impart swellability 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 swellable fluorinated mica tends to decrease.

Montmorillonite has a structural formula represented by the following formula.
M _a Si (Al ₂ -aMg) O ₁₀ (OH) ₂ .nH ₂ O
(In the formula, M represents a cation such as sodium, and 0.25 ≦ a ≦ 0.6. The number of water molecules bound to the ion-exchangeable cation between layers is the number of cation species, humidity, etc. (Because it can vary depending on conditions, it is expressed as nH ₂ O in the formula.)

Montmorillonite can be obtained by refining a naturally produced product by a water treatment or the like.

  It is known that montmorillonite has the same type of ion substitution product such as magnesia montmorillonite, iron montmorillonite, and iron magnesia montmorillonite, and these may be used.

Hectorite has a structural formula represented by the following formula, for example.
Na _0.66 (Mg _5.34 Li _0.66 ) Si ₈ O ₂₀ (OH) ₄ .nH ₂ O

  Hectorite may be obtained naturally or may be obtained by synthesis.

  Hectorite has a structure composed of a negatively charged silicate layer mainly composed of silicate and a cation having an ion exchange capacity interposed between the layers. Compared with other layered silicates, the hectorite has a hydroxyl group. Since it is contained in a large amount, water molecules can easily enter between layers (that is, hydrophilicity is high) and easily swell. In addition, the particle size is small compared to other layered silicates.

  The content of the swellable layered silicate (B) is required to be 1.0 to 10.0 parts by mass with respect to 100 parts by mass of the polyamide resin (A), and 1.0 to 9.0 parts by mass. It is preferable to be 3.0 to 8.0 parts by mass. When the content of the swellable layered silicate (B) is less than 1.0 part by mass, the flop index is lowered and a pearly hue cannot be obtained. On the other hand, when the content exceeds 10.0 parts by mass, the hue angle range becomes narrow, or agglomerates of swellable layered silicate are generated and a good appearance cannot be obtained.

  As aluminum powder (C) used for this invention, what peeled and peeled the aluminum paste and the vacuum evaporation film | membrane is mentioned.

  The average particle diameter of the aluminum powder (C) used in the present invention needs to be 10 to 35 μm, and since the hue angle range is widened, it is preferably 10 to 20 μm. When the average particle diameter of the aluminum powder (C) exceeds 35 μm, the resulting molded product has a lame tone and a pearl tone color cannot be obtained, which is not preferable. On the other hand, when the average particle diameter of the aluminum powder (C) is less than 10 μm, the concealability of the obtained molded product is increased and the hue angle range is narrowed, which is not preferable.

  The average particle diameter of the aluminum powder can be measured by a laser diffraction / scattering type particle size distribution measuring device, for example, Microtrack 2 (manufactured by Nikkiso Co., Ltd.). The average thickness of the aluminum powder can be calculated by a simple average of 50 aluminum powders measured by an electron microscope on the cross section of the molded product.

  The content of the aluminum powder (C) is required to be 0.04 to 0.5 parts by mass with respect to 100 parts by mass of the polyamide resin (A), and 0.04 to 0.3 parts by mass. Is preferable, and it is more preferable to set it as 0.05-0.2 mass part. When the content of the aluminum powder (C) is less than 0.04 parts by mass, it is not preferable because the change in brightness due to the viewing angle is not felt. On the other hand, when the content exceeds 0.5 parts by mass, the metallic tone becomes strong, the pearly tone is not obtained, and the metallic tone becomes too strong, which is not preferable.

  The pearl pigment (D) used in the present invention is a silver-white pigment having pearly luster. Examples of the pearl pigment (D) include titanium oxide-coated mica, titanium oxide-coated mica, bismuth oxychloride, titanium oxide-coated bismuth oxychloride, titanium oxide-coated talc, fish scale foil, titanium oxide-coated glass powder, and titanium oxide-coated colored mica. Is mentioned.

  The average particle size of the pearl pigment (D) is preferably 1 to 100 μm, more preferably 3 to 50 μm, and further preferably 5 to 25 μm. In addition, the measuring method of the average particle diameter of a pearl pigment (D) is the same as the measuring method of the average particle diameter of the above-mentioned aluminum powder.

  In addition, when it is going to give a pearl tone only with a pearl pigment (D), content of (D) will become high and an aggregate may generate | occur | produce and an external appearance may be impaired. Therefore, in this invention, a brightness feeling is improved by using aluminum powder (C) together, and the expression of pearl tone is enabled by blending a small amount of pearl pigment (D).

  The content of the pearl pigment (D) is required to be 0.7 to 5.0 parts by mass with respect to 100 parts by mass of the polyamide resin (A), and 1.0 to 5.0 parts by mass. Is preferable, and it is more preferable to set it as 1.0-3.0 mass parts. When the content of the pearl pigment (D) is less than 0.7 parts by mass, the hue angle range becomes narrow, and a pearly hue cannot be obtained. On the other hand, when the content exceeds 5.0 parts by mass, an agglomerate of pearl pigment is generated and a good appearance cannot be obtained.

  The mass ratio [(C) / (D)] of the content of the aluminum powder (C) and the pearl pigment (D) needs to be 0.01 to 0.70, and is 0.01 to 0.50. Preferably there is. When the content ratio is less than 0.01, the flip index becomes small, and a pearly hue cannot be obtained. On the other hand, when the mass ratio exceeds 0.70, the flop index becomes large and the metallic tone becomes too strong, which is not preferable.

  As long as the effects of the present invention are not impaired, additives such as pigments, plasticizers, lubricants, mold release agents, and antistatic agents may be added to the polyamide resin composition of the present invention. The method of mixing these with the polyamide resin composition of the present invention is not particularly limited.

  The method for producing the polyamide resin composition of the present invention is not particularly limited. For example, in the presence of the swellable layered silicate (B), the monomer component constituting the polyamide resin (A) is polymerized to swell. Examples thereof include a method in which a polyamide resin containing a layered silicate is obtained, and the polyamide resin, an aluminum powder (C), and a pearl pigment (D) are melt mixed. By producing by the above method, the swellable layered silicate (B) can be uniformly dispersed in the polyamide resin (A), and a pearly hue can be obtained.

  When the polyamide resin (A) is a copolymer, a copolymerization reaction of two or more monomers is performed in the presence of the swellable layered silicate (B), and a polyamide resin containing the swellable layered silicate is obtained. Examples thereof include a method in which the polyamide resin, the aluminum powder (C), and the pearl pigment (D) are melt-mixed and manufactured.

  Further, when the polyamide resin (A) is a molten mixture of two or more kinds of polyamide resins, it contains a swellable layered silicate by performing a polymerization reaction of at least one of the two or more kinds of polymers. A polyamide resin composition is obtained by melt-mixing the polyamide resin and another polyamide resin (or a polyamide resin containing a swellable layered silicate), an aluminum powder (C), and a pearl pigment (D). The method of manufacturing is mentioned.

  When using a molten mixture of two or more polyamide resins as the polyamide resin (A), it is preferable that they are sufficiently melt-kneaded. When the melt viscosity difference between the two types of polyamide resins to be melt-mixed is large or the difference in melting points is large, melt-kneading becomes insufficient, and the polyamide resins may not be uniformly mixed but may have a sea-island structure. In such a case, it becomes difficult to uniformly orient the contained aluminum powder (C) when obtaining a molded body, so that the pearl tone may be partially impaired or spots may occur.

  As a method for polymerizing the polyamide resin in the presence of the swellable layered silicate (B), after the swellable layered silicate (B) and the monomer are charged into an autoclave, the temperature is determined using an initiator such as water. Examples include a method of melt polycondensation within a range of 240 to 300 ° C., a pressure of 0.2 to 3 MPa, and a time of 1 to 15 hours. When ε-caprolactam is used as the monomer, it is preferable to perform melt polycondensation at a temperature of 250 to 280 ° C., a pressure of 0.5 to 2 MPa, and a range of 3 to 5 hours.

  In order to remove the monomer remaining in the polyamide resin after polymerization, it is preferable to scour the polyamide resin pellets with hot water. As a refinement | purification method, the method of processing for 8 hours or more in 90-100 degreeC hot water is mentioned, for example.

  When the polyamide resin containing the swellable layered silicate, the aluminum powder (C), and the pearl pigment (D) are melt-mixed, a known melt-kneading extruder can be used. As a method for supplying aluminum powder (C) and pearl pigment (D) to a melt-kneading extruder, aluminum powder (C) and pearl pigment (D) were mixed with the polyamide resin containing the swellable layered silicate. Although it is possible to put in a batch from the main hopper, it is preferable to supply the aluminum powder (C) from the middle of the extruder with a side feeder in order to suppress crushing or breakage of the aluminum powder (C) as much as possible. More preferably, the position is as downstream as possible in the extruder.

  In addition, the polyamide resin containing the swellable layered silicate, the aluminum powder (C), and the pearl pigment (D) may not be sufficiently melt-kneaded. What is necessary is just to be able to mix in the range which is not. In the present invention, a dry blend of the polyamide resin containing the swellable layered silicate, the aluminum powder (C), and the pearl pigment (D) may be directly supplied to an injection molding machine. Injection molding may be performed after melt-kneading.

  Aluminum powder (C) is brittle to external stress. Therefore, from the viewpoint of the expression of pearl tone, it is preferable that the screw shear stress during melt-kneading is not applied to the aluminum powder (C) as much as possible in the production of the resin composition and the molding of the molded body.

  The polyamide resin composition of the present invention can be molded by various molding methods. Examples of the molding method include injection molding, blow molding, extrusion molding, inflation molding, vacuum molding after sheet processing, pressure molding, vacuum pressure molding, and the like. Among these, injection molding is preferable. As an injection molding method, in addition to a general injection molding method, gas injection molding, injection press molding, or the like can be employed.

  As injection molding conditions suitable for the polyamide resin composition of the present invention, for example, the cylinder temperature is set to the melting point or flow start temperature of the resin composition or higher, preferably 190 to 270 ° C., and the mold temperature is set to that of the resin composition. It is preferable to set it below (melting point-20 degreeC). If the molding temperature is too low, the moldability may become unstable, such as a short circuit occurring in the molded body. On the other hand, if the molding temperature is too high, the polyamide resin composition may be decomposed and the strength of the resulting molded product may be reduced or the pearl tone may not be exhibited.

  The polyamide resin composition of the present invention is susceptible to fluidity and dispersibility in the mold depending on various conditions during injection molding, such as resin temperature, injection speed, injection pressure, and mold temperature. For example, when the injection speed is high, the orientation of the aluminum powder (C) is disturbed and flow marks are likely to be generated. Therefore, the injection speed should be low to medium.

  The molded body obtained from the polyamide resin composition of the present invention can be suitably used for automobile parts, electric / electronic parts, and daily necessities. Examples of automotive parts include various instruments such as speedometers, tachometers, fuel gauges, water temperature gauges, and distance meters in instrument panels, car stereos, navigation systems, various switches around air conditioners, buttons, and center consoles. Shift lever, side brake grip, door trim, armrest, door lever. Examples of the electrical / electronic parts include various parts and casings around a personal computer, cellular phone parts and casings, and other electrical equipment parts such as OA equipment and television. The daily necessities include cosmetic containers.

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

1. Evaluation Method (1) Preparation of Test Specimen Using the obtained polyamide resin composition, a FANUC ROBOSHOT S-2000iB type injection molding machine has a resin temperature of 270 ° C., a mold temperature of 100 ° C., a holding pressure of 30 MPa, and an injection. Injection molding was performed under the conditions of a speed of 20 mm / second, an injection pressure of 100 MPa, and a cooling time of 15 seconds to obtain a plate-shaped molded body having a mirror surface of 90 mm long × 50 mm wide × 2 mm thick. A mold having a film gate at the center in the short side direction was used.

(2) Content of the swellable layered silicate in the test piece The test piece obtained in (1) was treated at 600 ° C. for 12 hours using a hot air oven to obtain ash, The content was determined.

(3) Using a multi-angle colorimeter (BYK-maci, a multi-color colorimeter for metallic coating, manufactured by Big Chemie Co., Ltd.), the incident angle is 45 ° and the reflection viewing angle is 15 for the test piece obtained with the flop index (1). L ^* was measured at 45 ° and 110 °, and the flop index was calculated using the following equation.

(4) Hue angle range The specimen obtained in (1) was measured using a multi-angle colorimeter (BYK-maci, a multi-angle colorimeter for metallic coating, manufactured by BYK Chemie Co., Ltd.) with an incident angle of 45 ° and a reflection field angle. Measurements of a ^* and b ^* were performed at (θn) -15, 15, 25, 45, 75, and 110 °, and the hue angle range was calculated using the following equation.

(5) Appearance About 10 test pieces obtained in (1), the appearance was evaluated according to the following criteria using scratches / foreign matter / reference gauge (made by TOMMY).
A: The total number of aggregates having a major axis of 0.1 mm or more and less than 0.7 mm was 25 or less, and there was no aggregate of 0.7 mm or more.
X: The total number of aggregates having a major axis of 0.1 mm or more and less than 0.7 mm was 26 or more, or aggregates of 0.7 mm or more were 1 or more.

2. Raw material (1) Polyamide resin (A)
・ Polyamide resin (A-8)
Polyamide 11, “BMN O” manufactured by Arkema
・ Polyamide resin (A-9)
Polyamide 12, "AMN O TLD" manufactured by Arkema

(2) Swellable layered silicate (B)
B-1: swellable fluoromica, “ME-100” manufactured by Co-op Chemical Co., average particle size 6.0 μm, cation exchange capacity 110 meq / 100 g
B-2: swellable montmorillonite, “Jungel HV” manufactured by Hojun Co., Ltd., average particle size 5.0 μm, cation exchange capacity 70 meq / 100 g
B-3: Swellable hectorite, “Bentone HC” manufactured by Elementis Specialties, cation exchange capacity: 80 meq / 100 g

(3) Aluminum powder (C)
C-1: Aluminum paste, “Silbead M050-AP” manufactured by Asahi Kasei Chemicals Corporation, average particle diameter 5 μm, average thickness 0.1 μm, solid content 90 mass%, polyethylene glycol 10 mass%
C-2: Aluminum paste, “Silbeads M100-BP” manufactured by Asahi Kasei Chemicals Corporation, average particle size 10 μm, average thickness 0.2 μm, solid content 90% by mass, polyethylene glycol 10% by mass
C-3: Aluminum paste, “Silbead M200-BP” manufactured by Asahi Kasei Chemicals Corporation, average particle size 20 μm, average thickness 0.4 μm, solid content 90% by mass, polyethylene glycol 10% by mass
C-4: Aluminum paste, “Silbead M350-BP” manufactured by Asahi Kasei Chemicals Corporation, average particle size 35 μm, average thickness 0.4 μm, solid content 90% by mass, polyethylene glycol 10% by mass
C-5: high-brightness metallic powder, “Elgie neo # 325” manufactured by Oike Imaging, average particle size 35 μm, average thickness 2 μm
C-6: high-intensity metallic powder, “Elgeo # 200” manufactured by Oike Imaging, average particle diameter 60 μm, average thickness 2 μm

(4) Pearl pigment (D)
・ "Magnapear 2100" manufactured by BASF, average particle size of 5 to 21 m

(5) Polyamide resin containing swellable layered silicate (A-1)
To 100 parts by mass of ε-caprolactam, 0.4 parts by mass of phosphorous acid, 4 parts by mass of swellable fluorinated mica (B-1), and 5 parts by mass of water were added and stirred at 80 ° C. for 1 hour, and then 260 ° C. The mixture was stirred at 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 a swellable layered silicate.

・ (P-2) to (P-7)
A polyamide resin containing a swellable layered silicate was prepared by performing the same operation as that for producing a polyamide resin (A-1) containing a swellable layered silicate except that the charge composition was changed as shown in Table 1. (P-2) to (P-7) were obtained.

  Table 1 shows the charged composition and final composition of the polyamide resins (P-1) to (P-7) containing the swellable layered silicate.

Example 1
100 parts by mass of polyamide resin (P-1) containing swellable layered silicate, 0.05 part by mass of aluminum powder (C-2), and 1 part by mass of pearl pigment (D) were dry blended. The obtained dry blend was charged from the main hopper of a single screw extruder, melt 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 260 ° C., a screw rotation of 200 rpm, and a discharge rate of 30 kg / hour.

Examples 2-20, Comparative Examples 1-11
Except having changed so that it might become the resin composition of Table 2, operation similar to Example 1 was performed and the polyamide resin composition pellet was obtained.

  Table 2 shows the evaluation results of the polyamide resin compositions obtained in Examples 1 to 20 and Comparative Examples 1 to 11.

The molded bodies obtained from the polyamide resin compositions of Examples 1 to 20 all have a flop index of 1.0 to 6.0, a hue angle range of 25 ° or more, and a pearly hue is obtained. It had an excellent appearance.
When the molded bodies obtained from the polyamide resin compositions of Examples 1 to 5 were compared, Examples 2 to 5 using a mixture of polyamide 6 and polyamide 11 or polyamide 12 were conducted using polyamide 6 alone. It can be seen that the hue angle range is wider and more pearly than in Example 1.

Since the molded product obtained from the polyamide resin composition of Comparative Example 1 had a small mass ratio of aluminum powder / pearl pigment, the flop index was less than 1, the change in brightness depending on the viewing angle was small, and a pearl tone was obtained. There wasn't.
The molded bodies obtained from the polyamide resin compositions of Comparative Examples 2 and 3 had a large aluminum powder / pearl pigment mass ratio, and therefore had a flop index exceeding 6 and a metallic tone too strong.
In the molded product obtained from the polyamide resin composition of Comparative Example 4, the amount of the swellable layered silicate was small, so the flop index was less than 1, the change in brightness depending on the viewing angle was small, and a pearly hue was obtained. There wasn't.
Since the molded body obtained from the polyamide resin composition of Comparative Example 5 contained a large amount of swellable layered silicate, the flop index exceeded 6 and the metallic tone was too strong. Silicate aggregates were generated and a good appearance could not be obtained.
Since the molded body obtained from the polyamide resin composition of Comparative Example 6 contained a small amount of aluminum powder, the flop index was less than 1, the change in brightness depending on the viewing angle was small, and a pearl tone was not obtained.
Since the molded body obtained from the polyamide resin composition of Comparative Example 7 contained a large amount of aluminum powder, the flop index exceeded 6 and the metallic tone was too strong.
The molded product obtained from the polyamide resin composition of Comparative Example 8 had a small amount of pearl pigment, so the hue angle range was narrowed, and a pearly hue was not obtained.
Since the molded product obtained from the polyamide resin composition of Comparative Example 9 contained a large amount of the pearl pigment, aggregates of the pearl pigment were generated and a good appearance could not be obtained.
Since the molded product obtained from the polyamide resin composition of Comparative Example 10 had a small average particle diameter of the aluminum powder, the concealability of the molded product was increased, the hue angle range was narrowed, and a pearly hue was not obtained.
The molded product obtained from the polyamide resin composition of Comparative Example 11 had a large average particle diameter of aluminum powder, so the flop index was less than 1, the change in brightness depending on the viewing angle was small, and a pearly hue was not obtained. .

Claims (5)

100 parts by mass of polyamide resin (A), 1.0 to 10.0 parts by mass of swellable layered silicate (B), 0.04 to 0.5 parts by mass of aluminum powder (C), and pearl pigment (D) 0.7 to 5.0 parts by mass, the average particle size of aluminum (C) is 10 to 35 μm, and the mass ratio of aluminum powder (C) to pearl pigment (D) [(C) / ( D)] is 0.01 to 0.7. The polyamide resin composition according to claim 1, wherein the polyamide resin (A) is a mixture of polyamide 6 and polyamide 11 or polyamide 12. The polyamide resin composition according to claim 2, wherein the ratio of polyamide 6 in the mixture of polyamide 6 and polyamide 11 or polyamide 12 is 70 to 90% by mass. The polyamide resin composition according to any one of claims 1 to 3, wherein the swellable layered silicate (B) is at least one selected from fluorine mica, montmorillonite and hectorite. The molded object which consists of a polyamide resin composition in any one of Claims 1-4.