JP2023072690A - Polyamide composition, molded article, and laminate - Google Patents

Abstract

To provide a polyamide composition which exhibits good welding strength and appearance when laser welded, and has excellent rigidity under an atmospheric equilibrium water absorption when formed into a molded article and good moldability.SOLUTION: There is provided a polyamide composition which comprises (A) a crystalline polyamide, (B) an amorphous polyamide, and (C) a laser light transmitting colorant, wherein the melting point (Tm) of the crystalline polyamide (A) is 290.0°C or less as measured by differential scanning calorimetry, the content of the amorphous polyamide (B) is 10.0 mass% or more and 50.0 mass% or less based on the mass of the total polyamide in the polyamide composition, and the amorphous polyamide (B) is dispersed in the crystalline polyamide (A) to form a domain.SELECTED DRAWING: None

Description

The present invention relates to polyamide compositions, molded articles, and laminates.

Polyamides typified by polyamide 6 (hereinafter also referred to as "PA6") and polyamide 66 (hereinafter also referred to as "PA66") are excellent in moldability, mechanical properties or chemical resistance, and are therefore used for automobiles. , for electrical and electronic purposes, for industrial materials, for industrial materials, for daily use, and for household goods.

In general, welding methods for secondary processing of polyamide resin compositions include laser welding, ultrasonic welding, vibration welding, hot plate welding, and the like. In particular, laser welding has advantages such as being able to perform welding without bringing a laser beam generator into contact with the welded area, less damage to the product due to no mechanical vibration, and being able to maintain a high level of airtightness. This welding method is in increasing demand.

As a laser welding method, a resin member having transparency to laser light (hereinafter referred to as "laser light transmitting material") and a resin member having absorption property to laser light (hereinafter referred to as "laser light absorbing material") are used. ) are superimposed and irradiated with laser light through a laser light transmitting material to weld the laser light transmitting material and the laser light absorbing material (see, for example, Patent Document 1, etc.). .

In addition, the laser light transmitting material includes a crystalline polyamide resin (A) having a melting point of 300 ° C. or higher as measured by a differential scanning calorimeter (DSC), and a melting point measured by a differential scanning calorimeter (DSC). A resin composition using an amorphous polyamide resin (B) that does not have a polyimide and a light-transmitting dye (C) is known (see, for example, Patent Document 2, etc.).

JP 2019-025673 A WO2019/160117

However, in the technique disclosed in Patent Document 1, although UL94 V-0 is achieved by adding a flame retardant to the laser light transmitting material, the laser transmittance is low, so a molded product having sufficient welding strength cannot be obtained. It is difficult to obtain, and there is room for improvement in rigidity under atmospheric equilibrium moisture absorption required for automobiles and various electric parts. In addition, since moldability such as plasticization time and releasability deteriorates due to the addition of a flame retardant, it is difficult to put it into practical use.
Although the technique disclosed in Patent Document 2 has superior laser light transmittance compared to Patent Document 1, the transmittance is still low enough to obtain a good laser-welded body, and some laser light that does not transmit does not transmit the laser light. The material heats up, and problems such as burning occur in the appearance of the laser welded body. Other problems can occur during injection molding, such as poor release from the mold and poor plasticization.
Thus, in the prior art, the fact is that there is still no known polyamide composition that exhibits good welding strength and appearance when laser-welded, has high rigidity under atmospheric equilibrium moisture absorption, and has excellent moldability. is.

The present invention has been made in view of the above circumstances, and a polyamide composition that exhibits good welding strength and appearance when laser welding, has excellent rigidity under atmospheric equilibrium moisture absorption, and has good moldability. and a molded article and laminate using the polyamide composition.

In addition, the present invention has been made in view of the above circumstances, and exhibits good welding strength and appearance when laser welding, excellent rigidity under atmospheric equilibrium moisture absorption, good moldability, Also provided are a polyamide composition having excellent flame retardancy, and a molded article and laminate using the polyamide composition.

That is, the present invention includes the following aspects.
(1) A polyamide composition containing (A) a crystalline polyamide, (B) an amorphous polyamide, and (C) a laser light transmitting colorant,
The melting point (Tm) of the (A) crystalline polyamide measured by a differential scanning calorimeter is 290.0° C. or less,
The content of the (B) amorphous polyamide is 10.0% by mass or more and 50.0% by mass or less with respect to the mass of the total polyamide in the polyamide composition,
A polyamide composition in which the (B) amorphous polyamide is dispersed in the (A) crystalline polyamide to form domains.
(2) A polyamide composition comprising (A) a crystalline polyamide, (B) an amorphous polyamide, (C) a laser light transmitting colorant, and (E) a phosphorus-based flame retardant,
The (A) crystalline polyamide has a melting point (Tm) of 290.0° C. or lower as measured by a differential scanning calorimeter,
The content of the (B) amorphous polyamide is 10.0% by mass or more and 50.0% by mass or less with respect to the mass of the total polyamide in the polyamide composition,
A polyamide composition in which the (B) amorphous polyamide is dispersed in the (A) crystalline polyamide to form domains.
(3) The (E) phosphorus-based flame retardant is selected from the group consisting of phosphinates represented by the following general formula (1), diphosphinates represented by the following general formula (2), and condensates thereof. The polyamide composition according to (2), comprising at least one phosphinate salt.

(In general formula (1), R ¹¹ and R ¹² are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. M ⁿ¹¹⁺ is an n11-valent metal ion M is an element belonging to group 2 or 15 of the periodic table, a transition element, zinc or aluminum n11 is 2 or 3. When n11 is 2 or 3, a plurality of ^R11 and Each R ¹² may be the same or different.
In general formula (2), R ²¹ and R ²² are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. Y ²¹ is an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 10 carbon atoms. M' _x ^m21+ is an m21 valent metal ion. M' is an element belonging to group 2 or group 15 of the periodic table, a transition element, zinc or aluminum. n21 is an integer of 1 or more and 3 or less. When n21 is 2 or 3, multiple R ²¹ , R ²² and Y ²¹ may be the same or different. m21 is 2 or 3; x is 1 or 2; When x is 2, multiple M' may be the same or different. n21, x and m21 are integers satisfying the relational expression 2*n21=m21*x. )

(4) The polyamide composition according to any one of (1) to (3), wherein the (A) crystalline polyamide is an aliphatic polyamide.
(5) The polyamide composition according to any one of (1) to (4), which contains 50 mol % or more of isophthalic acid units in all dicarboxylic acid units constituting the amorphous polyamide (B).
(6) The polyamide composition according to (5), which contains 75 mol % or more of isophthalic acid units in all dicarboxylic acid units constituting the amorphous polyamide (B).
(7) The polyamide composition according to (6), which contains 100 mol % of isophthalic acid units in all dicarboxylic acid units constituting the amorphous polyamide (B).
(8) Any one of (1) to (7), wherein the domain size of the (B) amorphous polyamide dispersed in the (A) crystalline polyamide has a number average particle size of 10 nm or more and 1000 nm or less. Polyamide composition according to.
(9) The content of (C) the laser light transmitting colorant is 0.01% by mass or more and 5.00% by mass or less with respect to the total mass of the polyamide composition, (1) to (8) ) The polyamide composition according to any one of ).
(10) A molded article obtained by molding the polyamide composition according to any one of (1) to (9).
(11) The molded article according to (10), wherein the molded article having a thickness of 2.0 mm has a transmittance of 40.0% or more for a laser beam having a wavelength of 900 nm.
(12) In the molded article having a thickness of 2.0 mm, the ratio of the minimum light transmittance T% _min and the maximum light transmittance T% _max at a wavelength of 900 nm or more to 1100 nm or less is T% _min /T% _max . , 0.750 or more, the molded article according to (10) or (11).
(13) A molded article obtained by molding the polyamide composition according to (2) or (3).
(14) The molded article according to (13), wherein the molded article having a thickness of 1.0 mm has a transmittance of 35.0% or more for a laser beam having a wavelength of 900 nm.
(15) The ratio of the minimum light transmittance T% _min to the maximum light transmittance T% _max at a wavelength of 900 nm or more and 1100 nm or less in the molded article having a thickness of 1.0 mm: T% _min / T% _max is 0.850 or more, the molded article according to (13) or (14).
(16) A laminate in which a laser light transmitting material and a laser light absorbing material are bonded together,
The laser light transmitting material is formed by molding the polyamide composition according to any one of (1) to (9),
The laser light absorbing material is formed by molding a composition containing a thermoplastic resin and a laser light absorbing colorant,
At least a part of a joint between the laser light transmitting material and the laser light absorbing material is a laser welded part.
(17) the difference in softening point between the laser light transmitting material and the laser light absorbing material is ±80.0° C. or less;
The laminate according to (16), wherein the softening point is the melting point Tm2 measured by a differential scanning calorimeter in the case of a crystalline resin, and the glass transition temperature Tg in the case of an amorphous resin.

According to the polyamide composition of the above aspect, when laser welding is performed, good welding strength and appearance are exhibited, and when molded into a molded product, it has excellent rigidity under moisture absorption in atmospheric equilibrium, and has good moldability. can provide things. In addition, according to the polyamide composition of the above aspect, when laser welding is performed, good welding strength and appearance are exhibited, and when a molded product is formed, it has excellent rigidity under moisture absorption in atmospheric equilibrium, and has good moldability. A polyamide composition having excellent flame retardancy can be provided. The molded article of the above embodiment uses the polyamide composition, exhibits good weld strength and appearance when laser welded, and is excellent in rigidity under atmospheric equilibrium moisture absorption. The laminate of the above aspect uses the polyamide composition, exhibits good welding strength and appearance, and is excellent in rigidity under atmospheric equilibrium moisture absorption.

EMBODIMENT OF THE INVENTION Hereinafter, the form (only henceforth "this embodiment") for implementing this invention is demonstrated in detail. The following embodiments are examples for explaining the present invention, and are not intended to limit the present invention to the following contents. The present invention can be appropriately modified and implemented within the scope of the gist thereof.

As used herein, the term "polyamide" means a polymer having an amide (--NHCO--) group in its main chain.

<<Polyamide composition>>
The polyamide composition of this embodiment contains (A) a crystalline polyamide, (B) an amorphous polyamide, and (C) a laser light transmitting colorant.

In another embodiment, the polyamide composition contains (A) a crystalline polyamide, (B) an amorphous polyamide, (C) a laser light transmitting colorant, and (E) a phosphorus-based flame retardant.

(A) The melting point (Tm) of the crystalline polyamide is 290.0° C. or lower, preferably 280.0° C. or lower, more preferably 220.0° C. or higher and 280.0° C. or lower, and 220.0° C. or higher and 270.0° C. or lower. 0° C. or lower is more preferable, and 240.0° C. or higher and 270.0° C. or lower is particularly preferable.
(A) When the melting point (Tm) of the crystalline polyamide is equal to or less than the above upper limit, a laser-welded article with a thermoplastic resin having excellent welding strength and appearance can be obtained. In addition, thermal decomposition of the polyamide composition during melt processing such as extrusion and molding can be further suppressed. On the other hand, when the melting point (Tm) of (A) the crystalline polyamide is at least the above lower limit, it is possible to obtain a polyamide composition that is superior in heat rigidity and the like.
(A) The melting point (Tm) of the crystalline polyamide can be measured according to JIS-K7121, and the measuring device is a differential scanning calorimeter (DSC). and Diamond-DSC manufactured by Epson.

(B) The content of the amorphous polyamide is 10.0% by mass or more and 50.0% by mass or less, and 10.0% by mass or more and 45.0% by mass, based on the mass of the total polyamide in the polyamide composition % or less is preferable, 12.5% by mass or more and 45.0% by mass or less is more preferable, 15.0% by mass or more and 42.5% by mass or less is more preferable, and 17.5% by mass or more and 40.0% by mass or less is More preferably, it is 20.0% by mass or more and 37.5% by mass or less, and most preferably 22.5% by mass or more and 35.0% by mass or less. (B) By setting the content of the amorphous polyamide in the above range, a polyamide composition having excellent moldability such as mechanical properties, especially rigidity under atmospheric equilibrium moisture absorption, mold releasability and plasticization stability can be obtained. can get. Moreover, a polyamide composition containing a component represented by an inorganic filler has excellent surface appearance.

In the polyamide composition of the present embodiment, the (B) amorphous polyamide is dispersed in the (A) crystalline polyamide to form domains.

By having the above configuration, the polyamide composition of the present embodiment exhibits good welding strength and appearance when laser welding is performed, and when formed into a molded product, has excellent rigidity under moisture absorption in atmospheric equilibrium, and is molded. It is possible to provide a polyamide composition having good properties.

Further, the polyamide composition of the present embodiment further contains (E) a phosphorus-based flame retardant, thereby providing a polyamide composition excellent in flame retardancy while maintaining the above characteristics.

In the following, (A) crystalline polyamide, (B) amorphous polyamide, (C) laser light transmitting colorant, and (E) phosphorus-based flame retardant are used as component (A) and component (B), respectively. , (C) component, and (E) component.

<Characteristics of Polyamide Composition>
In the polyamide composition of the present embodiment, the melting point Tm2 can be configured as follows.

[Melting point Tm2 of polyamide composition]
The melting point Tm2 of the polyamide composition is preferably 330.0° C. or lower, more preferably 300.0° C. or lower, even more preferably 290.0° C. or lower, still more preferably 280.0° C. or lower, and 220.0° C. or higher and 280 0°C or less is more preferable, 220.0°C or more and 270.0°C or less is particularly preferable, and 240.0°C or more and 270.0°C or less is most preferable.
When the melting point Tm2 of the polyamide composition is equal to or less than the above upper limit, a laser-welded article with a thermoplastic resin having excellent welding strength and product appearance can be obtained. In addition, thermal decomposition of the polyamide composition during melt processing such as extrusion and molding can be further suppressed. On the other hand, when the melting point Tm2 of the polyamide composition is equal to or higher than the above lower limit, it is possible to obtain a polyamide composition which is excellent in heat rigidity and the like.
The melting point Tm2 of the polyamide composition can be measured according to JIS-K7121, and examples of measuring devices include Diamond-DSC manufactured by PERKIN-ELMER.

[Domain Size of Amorphous Polyamide]
In the polyamide composition of the present embodiment, the (B) amorphous polyamide is dispersed in the (A) crystalline polyamide to form domains, and the number average particle diameter of the domain size is preferably 10 nm or more and 1000 nm or less, and 20 nm. It is more preferably 500 nm or less, more preferably 30 nm or more and 300 nm or less, even more preferably 50 nm or more and 150 nm or less, particularly preferably 60 nm or more and 110 nm or less, and most preferably 60 nm or more and 80 nm or less. When the average primary particle size is within this range, it is possible to further improve the transmittance of laser light and the rigidity under atmospheric equilibrium moisture absorption when formed into a molded article.

Each constituent component contained in the polyamide composition of the present embodiment will be described below.

<(A) Crystalline Polyamide>
A crystalline polyamide is a polyamide having a heat of fusion of crystals of 4 J/g or more when measured at 20° C./min with a differential scanning calorimeter.

Examples of (A) crystalline polyamides include, but are not limited to, (Aa) polyamides obtained by ring-opening polymerization of lactams, (Ab) polyamides obtained by self-condensation of ω-aminocarboxylic acids, (Ac) polyamides obtained by condensing diamines and dicarboxylic acids, copolymers thereof, and the like. The crystalline polyamide may be used singly or as a mixture of two or more.
Among them, the crystalline polyamide is preferably an aliphatic polyamide in which the carbon skeleton forming the monomer units is composed of an aliphatic hydrocarbon group.

(Aa) Lactams used in polyamides obtained by ring-opening polymerization of lactams include, but are not limited to, pyrrolidone, caprolactam, undecalactam, dodecalactam, and the like.

(Ab) The ω-aminocarboxylic acid used in the polyamide obtained by self-condensation of ω-aminocarboxylic acid is not limited to the following, but for example, ω-amino which is a ring-opening compound of the above lactam with water Fatty acid etc. are mentioned. As a lactam or ω-aminocarboxylic acid, two or more monomers may be used in combination for condensation.

(Ac) The diamine (monomer) used in the polyamide obtained by condensing a diamine and a dicarboxylic acid is not limited to the following, but examples include ethylenediamine, propylenediamine, tetramethylenediamine, and pentamethylenediamine. , hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, tridecamethylenediamine, and other linear saturated aliphatic diamines having 2 to 20 carbon atoms etc.

The diamine constituting the diamine unit having a substituent branched from the main chain is not limited to the following, but for example, 2-methylpentamethylenediamine (also referred to as 2-methyl-1,5-diaminopentane) , 2,2,4-trimethylhexamethylenediamine, 2,4,4-trimethylhexamethylenediamine, 2-methyl-1,8-octanediamine (also referred to as 2-methyloctamethylenediamine), 2,4-dimethylocta Branched saturated aliphatic diamines having 3 or more and 20 or less carbon atoms such as methylenediamine may be used.
Among them, 2-methylpentamethylenediamine or 2-methyl-1,8-octanediamine is preferable as the diamine constituting the diamine unit having a substituent branched from the main chain, and 2-methylpentamethylenediamine is more preferable. By containing such an aliphatic diamine, the polyamide composition tends to be more excellent in heat resistance, rigidity, and the like.

The above diamines as monomers may be used alone or in combination of two or more.

The number of carbon atoms in the diamine unit is preferably 4 or more and 12 or less, more preferably 4 or more and 10 or less. When the number of carbon atoms is at least the above lower limit, the heat resistance is excellent, while when it is at most the above upper limit, the crystallinity and releasability are excellent.

In addition, the aliphatic diamine may further contain a trivalent or higher polyvalent aliphatic amine such as bishexamethylenetriamine, if necessary.
These diamines may be used alone or in combination of two or more.

(Ac) The dicarboxylic acid (monomer) used in the polyamide obtained by condensing a diamine and a dicarboxylic acid is not limited to the following, but for example, succinic acid, adipic acid, pimelic acid, sebacic acid , dodecanedioic acid, tetradecanedioic acid, etc.; aromatic dicarboxylic acids; and alicyclic dicarboxylic acids such as cyclohexanedicarboxylic acid. The above dicarboxylic acids as monomers may be used alone or in combination of two or more.

In addition, (A) the crystalline polyamide may further contain units derived from polycarboxylic acids having a valence of 3 or more, such as trimellitic acid, trimesic acid, and pyromellitic acid, if necessary. The trivalent or higher polyvalent carboxylic acid may be used alone or in combination of two or more.

(A) Specific examples of crystalline polyamides include polyamide 4 (polyα-pyrrolidone), polyamide 6 (polycaproamide), polyamide 11 (polyundecaneamide), polyamide 12 (polydodecanamide), polyamide 46 (poly tetramethylene adipamide), polyamide 56 (polypentamethylene adipamide), polyamide 66 (polyhexamethylene adipamide), polyamide 610 (polyhexamethylene sebacamide), polyamide 612 (polyhexamethylene dodecamide), Examples include polyamide 4T (polytetramethylene terephthalamide), polyamide 6T (polyhexamethylene terephthalamide), polyamide 9T (polynonanemethylene terephthalamide), and copolymerized polyamides containing these as constituents.

Among them, polyamide 6, polyamide 46, polyamide 66, or polyamide 610 is preferred, polyamide 6, polyamide 66, or polyamide 610 is more preferred, polyamide 6 or polyamide 66 is even more preferred, and polyamide 66 is particularly preferred. Polyamide 66 is considered to be a suitable material for automobile parts because of its excellent heat resistance, moldability and toughness. In addition, long-chain aliphatic polyamides such as polyamide 610 are excellent in chemical resistance.

[(A) Characteristics of crystalline polyamide]
((A) weight average molecular weight Mw (A) of crystalline polyamide)
(A) A weight average molecular weight can be used as an index of the molecular weight of the crystalline polyamide.

(A) The weight average molecular weight (Mw(A)) of the crystalline polyamide is preferably 10,000 or more and 50,000 or less, more preferably 15,000 or more and 45,000 or less, still more preferably 20,000 or more and 40,000 or less, and particularly preferably 25,000 or more and 40,000 or less.
When Mw (A) is within the above range, it is possible to obtain a polyamide composition which simultaneously satisfies mechanical properties, particularly water absorption stiffness, heat stiffness, fluidity, corrosion resistance, and the like. In addition, a molded article obtained from a polyamide composition containing a component typified by an inorganic filler has a more excellent surface appearance.
The weight average molecular weight (Mw(A)) of the crystalline polyamide (A) can be measured using gel permeation chromatography (GPC).

(Molecular weight distribution of (A) crystalline polyamide)
(A) The molecular weight distribution of the crystalline polyamide is the value Mw ( A)/Mn(A) is used as an index.
Mw(A)/Mn(A) is preferably 1.0 or more, more preferably 1.8 or more and 2.2 or less, and still more preferably 2.0 or more and 2.2 or less.
When Mw(A)/Mn(A) is within the above range, a polyamide composition having excellent fluidity and the like can be obtained. In addition, a molded article obtained from a polyamide composition containing a component typified by an inorganic filler has a more excellent surface appearance.

Methods for controlling Mw(A)/Mn(A) within the above range include, for example, methods shown in 1) or 2) below.
1) A method of adding a known polycondensation catalyst such as phosphoric acid or sodium hypophosphite as an additive during thermal melt polymerization of polyamide.
2) In addition to the above method 1), a method of controlling polymerization conditions such as heating conditions and pressure reduction conditions.

Note that Mw(A)/Mn(A) can be calculated using Mw(A) and Mn(A) obtained using GPC.

((A) Enthalpy of crystallization ΔH of crystalline polyamide)
(A) The lower limit of the crystallization enthalpy ΔH of the crystalline polyamide is preferably 30 J/g, more preferably 40 J/g, and even more preferably 50 J/g, from the viewpoint of mechanical properties, particularly water absorption stiffness and heat stiffness. 60 J/g is particularly preferred. On the other hand, the upper limit of the crystallization enthalpy ΔH of the crystalline polyamide (A) is not particularly limited, and the higher the better.
(A) The enthalpy of crystallization ΔH of the crystalline polyamide can be measured according to JIS-K7121, and examples of measuring devices include Diamond-DSC manufactured by PERKIN-ELMER.

[(A) Content of crystalline polyamide]
In the polyamide composition of the present embodiment, the content of (A) the crystalline polyamide can be 50.0% by mass or more and 90.0% by mass or less with respect to the total amount of polyamide in the polyamide composition. 0% by mass or more and 90.0% by mass or less is preferable, 55.0% by mass or more and 87.5% by mass or less is more preferable, 57.5% by mass or more and 87.5% by mass or less is even more preferable, and 60.0% by mass % or more and 82.5 mass % or less is more preferable, 62.5 mass % or more and 80.0 mass % or less is particularly preferable, and 65.0 mass % or more and 72.5 mass % or less is most preferable.
By setting the blending amount of (A) the crystalline polyamide within the above range, it is possible to obtain a polyamide composition which is excellent in mechanical properties, particularly in hot rigidity, fluidity, corrosion resistance, and the like. Moreover, the polyamide composition containing the component represented by the inorganic filler has a more excellent surface appearance.

In the polyamide composition of the present embodiment, the content of (A) the crystalline polyamide is, for example, 10.0% by mass or more and 60.0% by mass or less with respect to the total mass of the polyamide composition, It can be 15.0% by mass or more and 55.0% by mass or less, can be 20.0% by mass or more and 53.0% by mass or less, and can be 25.0% by mass or more and 50.0% by mass or less. be able to.

<(B) amorphous polyamide>
Amorphous polyamide refers to a polyamide having an enthalpy of crystallization ΔH of 15 J/g or less when measured at 20° C./min with a differential scanning calorimeter. (B) The enthalpy of crystallization of the amorphous polyamide is preferably 10 J/g or less, more preferably 5 J/g or less, and even more preferably 0 J/g. The crystallization enthalpy ΔH can be measured, for example, according to JIS-K7121 using a measuring device such as Diamond-DSC manufactured by PERKIN-ELMER.
(B) The amorphous polyamide is not particularly limited as long as it has an enthalpy of crystallization ΔH of the above upper limit or less, but it may be a semi-aromatic polyamide.

When the amorphous polyamide (B) is a semi-aromatic polyamide, it is preferably a polyamide containing a diamine unit and a dicarboxylic acid unit.
(B) the amorphous polyamide comprises (B-a) a dicarboxylic acid unit containing at least 50 mol% of an isophthalic acid unit, and (B-b) a diamine unit containing at least 50 mol% of a diamine unit having 4 to 10 carbon atoms. and is preferably a polyamide containing.
The total amount of the isophthalic acid units and the diamine units having 4 to 10 carbon atoms is preferably 75 mol% or more and 100 mol% or less, and 90 mol%, based on the total amount of all structural units of the amorphous polyamide (B). 100 mol % or less is more preferable, and 100 mol % is even more preferable.
In the present invention, the ratio of the predetermined monomer units constituting (B) the amorphous polyamide can be measured by nuclear magnetic resonance spectroscopy (NMR) or the like.

[(Ba) dicarboxylic acid unit]
In (Ba) the dicarboxylic acid unit, the content of the isophthalic acid unit is preferably 50 mol% or more, particularly preferably 75 mol% or more and 100 mol% or less, and 90 mol% or more with respect to the total molar amount of the dicarboxylic acid units. 100 mol % or less is more preferable, and 100 mol % is particularly preferable.
The content of isophthalic acid units relative to the total number of moles of dicarboxylic acid is at least the above lower limit, so that mechanical properties, rigidity at the time of moisture absorption in atmospheric equilibrium, moldability, surface appearance, and welding strength during laser welding are improved. It is possible to obtain a polyamide composition which is more satisfactory in appearance and at the same time.

(Ba) dicarboxylic acid units may contain aromatic dicarboxylic acid units, aliphatic dicarboxylic acid units, and alicyclic dicarboxylic acid units other than isophthalic acid units.

(aromatic dicarboxylic acid unit)
Examples of the aromatic dicarboxylic acid constituting the aromatic dicarboxylic acid unit other than the isophthalic acid unit include, but are not limited to, dicarboxylic acids having a phenyl group and a naphthyl group. The aromatic group of the aromatic dicarboxylic acid may be unsubstituted or have a substituent.
Although the substituent is not particularly limited, for example, an alkyl group having 1 to 4 carbon atoms, an aryl group having 6 to 10 carbon atoms, an arylalkyl group having 7 to 10 carbon atoms, a chloro group, a bromo group, etc. , silyl groups having 1 to 6 carbon atoms, sulfonic acid groups and salts thereof (sodium salts, etc.), and the like.
Specifically, but not limited to, unsubstituted terephthalic acid, naphthalenedicarboxylic acid, 2-chloroterephthalic acid, 2-methylterephthalic acid, 5-methylisophthalic acid, 5-sodiumsulfoisophthalic acid, and the like. Alternatively, aromatic dicarboxylic acids having 8 or more and 20 or less carbon atoms substituted with predetermined substituents may be mentioned. Among them, terephthalic acid is preferred.
The aromatic dicarboxylic acids constituting the aromatic dicarboxylic acid unit may be used alone or in combination of two or more.

(aliphatic dicarboxylic acid unit)
The aliphatic dicarboxylic acid constituting the aliphatic dicarboxylic acid unit is not limited to the following, but examples include malonic acid, dimethylmalonic acid, succinic acid, 2,2-dimethylsuccinic acid, 2,3-dimethyl Glutaric acid, 2,2-diethylsuccinic acid, 2,3-diethylglutaric acid, glutaric acid, 2,2-dimethylglutaric acid, adipic acid, 2-methyladipic acid, trimethyladipic acid, pimelic acid, suberic acid, azelaine Acid, sebacic acid, dodecanedioic acid, tetradecanedioic acid, hexadecanedioic acid, octadecanedioic acid, eicosanedioic acid, diglycolic acid, linear or branched saturated aliphatic dicarboxylic acids having 3 to 20 carbon atoms, etc. are mentioned.

(Alicyclic dicarboxylic acid unit)
The alicyclic dicarboxylic acid constituting the alicyclic dicarboxylic acid unit (hereinafter also referred to as "alicyclic dicarboxylic acid unit") is not limited to the following, but for example, the number of carbon atoms in the alicyclic structure is An alicyclic dicarboxylic acid having 3 or more and 10 or less carbon atoms is mentioned, and an alicyclic dicarboxylic acid having an alicyclic structure having 5 or more and 10 or less carbon atoms is preferable.
Examples of such alicyclic dicarboxylic acids include, but are not limited to, 1,4-cyclohexanedicarboxylic acid, 1,3-cyclohexanedicarboxylic acid, and 1,3-cyclopentanedicarboxylic acid. mentioned. Among them, 1,4-cyclohexanedicarboxylic acid is preferred.
In addition, the alicyclic dicarboxylic acid that constitutes the alicyclic dicarboxylic acid unit may be used alone, or two or more of them may be used in combination.

The alicyclic group of the alicyclic dicarboxylic acid may be unsubstituted or have a substituent. Examples of substituents include, but are not limited to, those having 1 to 4 carbon atoms such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, and tert-butyl. Examples include the following alkyl groups.
Dicarboxylic acid units other than isophthalic acid units preferably include aromatic dicarboxylic acid units, and more preferably include aromatic dicarboxylic acid units having 6 or more and 12 or less carbon atoms.
By using such a dicarboxylic acid, the polyamide composition tends to be more excellent in mechanical properties, particularly water absorption rigidity, heat rigidity, fluidity, surface appearance, corrosion resistance, and the like.

In the polyamide composition of the present embodiment, the (Ba) dicarboxylic acid constituting the dicarboxylic acid unit is not limited to the compounds described as the dicarboxylic acid, and is a compound equivalent to the dicarboxylic acid. good too.
Here, "a compound equivalent to a dicarboxylic acid" refers to a compound capable of forming a dicarboxylic acid structure similar to the dicarboxylic acid structure derived from the above dicarboxylic acid. Examples of such compounds include, but are not limited to, anhydrides and halides of dicarboxylic acids.

In addition, (B) the amorphous polyamide may further contain units derived from polycarboxylic acids having a valence of 3 or more, such as trimellitic acid, trimesic acid, and pyromellitic acid, if necessary.
The polyvalent carboxylic acid having a valence of 3 or more may be used alone, or two or more of them may be used in combination.

[(Bb) diamine unit]
The (Bb) diamine units constituting the (B) amorphous polyamide preferably contain at least 50 mol % of diamine units having 4 to 10 carbon atoms. Examples include, but are not limited to, aliphatic diamine units, alicyclic diamine units, and aromatic diamine units.

(aliphatic diamine unit)
Aliphatic diamines constituting the aliphatic diamine unit are not limited to the following, but examples include ethylenediamine, propylenediamine, tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, Straight-chain saturated aliphatic diamines having 2 to 20 carbon atoms such as nonamethylenediamine, decamethylenediamine, undecamethylenediamine, dodecamethylenediamine, and tridecamethylenediamine.

(alicyclic diamine unit)
The alicyclic diamine (hereinafter also referred to as "alicyclic diamine") constituting the alicyclic diamine unit is not limited to the following, but examples include 1,4-cyclohexanediamine, 1,3- cyclohexanediamine, 1,3-cyclopentanediamine and the like.

(aromatic diamine unit)
The aromatic diamine constituting the aromatic diamine unit is not limited to the following as long as it is a diamine containing an aromatic group, and examples thereof include meta-xylylenediamine.

Among them, an aliphatic diamine unit is preferable, a diamine unit having a linear saturated aliphatic group having 4 to 10 carbon atoms is more preferable, and a diamine unit having a linear saturated aliphatic group having 6 to 10 carbon atoms is More preferred, hexamethylenediamine units are particularly preferred.
By using such a diamine, the polyamide composition tends to be more excellent in mechanical properties, particularly water absorption rigidity, heat rigidity, fluidity, surface appearance, corrosiveness, and the like.
In addition, diamine may be used individually and may be used in combination of 2 or more types.

(B) The amorphous polyamide is preferably polyamide 6I, 6I/6T, 9I, or 10I, more preferably 6I or 6I/6T, and most preferably 6I.

In addition, (B) the amorphous polyamide may further contain a polyvalent aliphatic amine having a valence of 3 or more, such as bishexamethylenetriamine, if necessary.
The polyvalent aliphatic amines having a valence of 3 or more may be used alone, or two or more of them may be used in combination.

[At least one unit selected from the group consisting of lactam units and aminocarboxylic acid units]
(B) The amorphous polyamide can further contain at least one unit selected from the group consisting of lactam units and aminocarboxylic acid units. Inclusion of such units tends to result in a polyamide having better toughness. In addition, the lactam and aminocarboxylic acid constituting the lactam unit and the aminocarboxylic acid unit refer to lactam and aminocarboxylic acid capable of poly(condensation) polymerization.

The lactams and aminocarboxylic acids constituting the lactam units and aminocarboxylic acid units are not limited to the following, but for example, lactams and aminocarboxylic acids having 4 to 14 carbon atoms are preferable, and More preferred are the following lactams and aminocarboxylic acids.

Examples of the lactam constituting the lactam unit include, but are not limited to, butyrolactam, pivalolactam, ε-caprolactam, caprylolactam, enantholactam, undecanolactam, laurolactam (dodecanolactam), and the like. be done.
Among them, the lactam is preferably ε-caprolactam or laurolactam, more preferably ε-caprolactam. The inclusion of such lactams tends to result in polyamides with better toughness.

Examples of the aminocarboxylic acid constituting the aminocarboxylic acid unit include, but are not limited to, ω-aminocarboxylic acids and α,ω-amino acids, which are lactam ring-opened compounds.
As the aminocarboxylic acid, a linear or branched saturated aliphatic carboxylic acid having 4 or more and 14 or less carbon atoms substituted with an amino group at the ω-position is preferable. Examples of such aminocarboxylic acids include, but are not limited to, 6-aminocaproic acid, 11-aminoundecanoic acid, 12-aminododecanoic acid and the like. Moreover, para-aminomethyl benzoic acid etc. are mentioned as an aminocarboxylic acid.

The lactams and aminocarboxylic acids that constitute the lactam units and aminocarboxylic acid units may be used alone, or two or more of them may be used in combination.

The total proportion (mol%) of the lactam units and aminocarboxylic acid units is preferably 0 mol% or more and 20 mol% or less, more preferably 0 mol% or more and 10 mol% or less, and 0 mol% or more and 5 mol % or less is more preferable.
When the total ratio of lactam units and aminocarboxylic acid units is within the above range, there is a tendency that effects such as improved fluidity can be obtained.

[(B) Characteristics of amorphous polyamide]
((B) Weight average molecular weight Mw (B) of amorphous polyamide)
As an index of the molecular weight of the (B) amorphous polyamide, the weight average molecular weight (Mw(B)) of the (B) amorphous polyamide can be used.

(B) The weight average molecular weight (Mw (B)) of the amorphous polyamide is preferably 10000 or more and 35000 or less, more preferably 10000 or more and 33000 or less, still more preferably 13000 or more and 30000 or less, and even more preferably 15000 or more and 29000 or less. , from 18,000 to 27,000, and most preferably from 19,000 to 21,000.
(B) When the weight average molecular weight (Mw (B)) of the amorphous polyamide is within the above range, the mechanical properties, particularly water absorption rigidity, heat rigidity, and fluidity are excellent, and the welding strength and product appearance are better. A polyamide composition capable of providing an excellent laser-welded body is obtained. In addition, a molded article obtained from a polyamide composition containing a component typified by an inorganic filler has a more excellent surface appearance.

In addition, (A) in order to reduce the number average particle size of the domains in the crystalline polyamide, it is desirable to improve the physical kneading efficiency, and the melt viscosity in the molten state is brought close to reduce the number average particle size. can do. The (B) amorphous polyamide containing aromatic compound units in the molecular structure of the polyamide has a higher melt viscosity if it has the same molecular weight as the (A) crystalline polyamide, so the molecular weight is higher than that of the (A) crystalline polyamide. A smaller value is desirable.

The weight-average molecular weight (Mw(B)) of the (B) amorphous polyamide can be measured using GPC.

(Molecular weight distribution of (B) amorphous polyamide)
(B) The molecular weight distribution of the amorphous polyamide is obtained by dividing the weight average molecular weight (Mw (B)) of the (B) amorphous polyamide by the number average molecular weight (Mn (B)) of the (B) amorphous polyamide. The value Mw(B)/Mn(B) is used as an index.

Mw (B)/Mn (B) is preferably 1.0 or more and 2.6 or less, more preferably 1.3 or more and 2.5 or less, further preferably 1.5 or more and 2.5 or less, and 1.8 or more and 2 0.4 or less is particularly preferable, and 2.0 or more and 2.4 or less is most preferable.
When Mw(B)/Mn(B) is within the above range, a polyamide composition having excellent moldability, welding strength during laser welding, and appearance can be obtained.
In addition, a molded article obtained from a polyamide composition containing a component typified by an inorganic filler has a more excellent surface appearance.

Methods for controlling Mw(B)/Mn(B) within the above range include, for example, methods shown in 1) or 2) below.
1) A method of adding a known polycondensation catalyst such as phosphoric acid or sodium hypophosphite as an additive during thermal melt polymerization of polyamide.
2) In addition to the above method 1), a method of controlling polymerization conditions such as heating conditions and pressure reduction conditions to complete the polycondensation reaction at the lowest possible temperature and in the shortest possible time.

When aromatic compound units are contained in the molecular structure of polyamide, the molecular weight distribution (Mw/Mn) tends to increase as the molecular weight increases. A high molecular weight distribution indicates a high proportion of polyamide molecules with a three-dimensional structure of the molecule. By reducing the proportion of polyamide molecules having a three-dimensional structure, the compatibility with (A) the crystalline polyamide can be enhanced and the number average particle size of the domains can be reduced. Therefore, by controlling Mw (B) / Mn (B) within the above range, the progress of three-dimensional structuring of molecules is suppressed during high-temperature processing, excellent fluidity, welding strength and product appearance are better. A polyamide composition capable of providing an excellent laser-welded body is obtained. In addition, the surface appearance of the molded article obtained from the polyamide composition containing the component typified by the inorganic filler is more excellent.

The measurement of Mw(B)/Mn(B) can be calculated using Mw(B) and Mn(B) obtained using GPC.

((B) Crystallization enthalpy of amorphous polyamide ΔH)
(B) The enthalpy of crystallization ΔH of the amorphous polyamide is preferably 15 J/g or less, more preferably 10 J/g or less, even more preferably 5 J/g or less, from the viewpoint of the light transmittance of the laser beam, and 0 J/g. is particularly preferred.
(B) As a method for controlling the enthalpy of crystallization ΔH of the amorphous polyamide within the above range, a known method for reducing the degree of crystallinity of the polyamide can be employed, and is not particularly limited. Specific methods for reducing the crystallinity of known polyamides include, for example, a method of increasing the ratio of meta-substituted aromatic dicarboxylic acid units to dicarboxylic acid units, and increasing the ratio of meta-substituted aromatic diamine units to diamine units. There is a method to increase it. From this point of view, the (B) amorphous polyamide may contain, as (Ba) dicarboxylic acid units, 50 mol% or more of isophthalic acid units in all dicarboxylic acid units constituting the (B) amorphous polyamide. It is preferably contained in an amount of 75 mol % or more, and more preferably in an amount of 100 mol %.

(B) The enthalpy of crystallization ΔH of the amorphous polyamide can be measured, for example, according to JIS-K7121, using a measuring device such as Diamond-DSC manufactured by Perkin-Elmer.

[(B) content of amorphous polyamide]
In the polyamide composition of the present embodiment, the content of (B) the amorphous polyamide is, for example, 1.0% by mass or more and 60.0% by mass or less with respect to the total mass of the polyamide composition. , 3.0% by mass or more and 40.0% by mass or less, 5.0% by mass or more and 30.0% by mass or less, and 7.0% by mass or more and 25.0% by mass or less. can do.

<Terminal blocking agent>
At least one polyamide selected from the group consisting of (A) crystalline polyamide and (B) amorphous polyamide has ends blocked with a terminal blocking agent.
Such a terminal blocker is used when producing a polyamide from the above-described dicarboxylic acid and diamine, and optionally at least one compound selected from the group consisting of lactams and aminocarboxylic acids, It can also be added as a molecular weight modifier.

Examples of terminal blocking agents include, but are not limited to, acid anhydrides, monoisocyanates, monoacid halides, monoesters, monoalcohols, monocarboxylic acids, and monoamines. Examples of acid anhydrides include phthalic anhydride and the like.
Among them, monocarboxylic acids or monoamines are preferred. By blocking the ends of the polyamide with a terminal blocking agent, the polyamide composition tends to be more excellent in thermal stability.
Terminal blockers may be used alone or in combination of two or more.

As the monocarboxylic acid that can be used as the terminal blocker, any one having reactivity with the amino group that can be present at the terminal of the polyamide can be used. Specific examples of monocarboxylic acids include, but are not limited to, aliphatic monocarboxylic acids, alicyclic monocarboxylic acids, and aromatic monocarboxylic acids.
Examples of aliphatic monocarboxylic acids include, but are not limited to, formic acid, acetic acid, propionic acid, butyric acid, valeric acid, caproic acid, caprylic acid, lauric acid, tridecylic acid, myristic acid, palmitic acid, stearic acid, pivalic acid, isobutyric acid and the like.
Examples of the alicyclic monocarboxylic acid include, but are not limited to, cyclohexanecarboxylic acid.
Examples of aromatic monocarboxylic acids include, but are not limited to, benzoic acid, toluic acid, α-naphthalenecarboxylic acid, β-naphthalenecarboxylic acid, methylnaphthalenecarboxylic acid, and phenylacetic acid.
These monocarboxylic acids may be used alone or in combination of two or more.

As the monoamine that can be used as the terminal blocking agent, any one having reactivity with the carboxyl group that may be present at the terminal of the polyamide may be used. Specific examples of monoamines include, but are not limited to, aliphatic monoamines, alicyclic monoamines, and aromatic monoamines.
Examples of aliphatic monoamines include, but are not limited to, methylamine, ethylamine, propylamine, butylamine, hexylamine, octylamine, decylamine, stearylamine, dimethylamine, diethylamine, dipropylamine, dibutylamine. etc.
Examples of the alicyclic monoamine include, but are not limited to, cyclohexylamine, dicyclohexylamine, and the like.
Examples of aromatic monoamines include, but are not limited to, aniline, toluidine, diphenylamine, naphthylamine, and the like.
These monoamines may be used alone or in combination of two or more.

A polyamide composition containing a polyamide terminally blocked with a terminal blocking agent has heat resistance, fluidity, toughness, low water absorption, rigidity, corrosion resistance, moldability, and welding strength when laser welding. They tend to look better.

<Method for producing polyamide>
When obtaining each polyamide ((A) crystalline polyamide and (B) amorphous polyamide), the amount of dicarboxylic acid added and the amount of diamine added are preferably about the same molar amount. Considering the amount of diamine that escapes to the outside of the reaction system during the polymerization reaction, the molar ratio of the total diamine to the total molar amount of dicarboxylic acid is preferably 0.9 or more and 1.2 or less. , is more preferably 0.95 or more and 1.1 or less, and more preferably 0.98 or more and 1.05 or less.

The method for producing polyamide includes, but is not limited to, the following polymerization step (1) or (2).
(1) A step of polymerizing a combination of a dicarboxylic acid constituting a dicarboxylic acid unit and a diamine constituting a diamine unit to obtain a polymer.
(2) A step of polymerizing at least one selected from the group consisting of lactams constituting lactam units and aminocarboxylic acids constituting aminocarboxylic acid units to obtain a polymer.

Moreover, it is preferable that the method for producing a polyamide further includes, after the polymerization step, a raising step for raising the degree of polymerization of the polyamide. Further, if necessary, a blocking step of blocking terminals of the obtained polymer with a terminal blocking agent may be included after the polymerization step and the rising step.

Specific methods for producing polyamides include, for example, various methods exemplified in 1) to 4) below.
1) Dicarboxylic acid-diamine salts, mixtures of dicarboxylic acids and diamines, lactams, and one or more aqueous solutions or aqueous suspensions selected from the group consisting of aminocarboxylic acids are heated to polymerize while maintaining the molten state. method (hereinafter sometimes referred to as “thermal melt polymerization method”).
2) A method of increasing the degree of polymerization of a polyamide obtained by a hot melt polymerization method while maintaining a solid state at a temperature below the melting point (hereinafter sometimes referred to as "hot melt polymerization/solid phase polymerization method").
3) A method of polymerizing one or more selected from the group consisting of a dicarboxylic acid-diamine salt, a mixture of a dicarboxylic acid and a diamine, a lactam, and an aminocarboxylic acid while maintaining a solid state (hereinafter referred to as "solid phase polymerization (sometimes referred to as “lawful”).
4) A method of polymerizing using a dicarboxylic acid halide component equivalent to the dicarboxylic acid and a diamine component (hereinafter sometimes referred to as "solution method").

Among them, as a specific method for producing a polyamide, a production method including a hot melt polymerization method is preferable. Moreover, when producing a polyamide by a hot melt polymerization method, it is preferable to maintain a molten state until the polymerization is completed. In order to maintain the molten state, it is necessary to carry out production under polymerization conditions suitable for polyamide. Polymerization conditions include, for example, the conditions shown below. First, the polymerization pressure in the hot melt polymerization method is controlled to 14 kg/cm ² or more and 25 kg/cm ² or less (gauge pressure), and heating is continued. Then, the pressure in the tank is lowered for 30 minutes or longer until the pressure reaches the atmospheric pressure (gauge pressure is 0 kg/cm ² ).

In the method for producing polyamide, the form of polymerization is not particularly limited, and may be a batch system or a continuous system.
A polymerization apparatus used for producing polyamide is not particularly limited, and a known apparatus can be used. Specific examples of the polymerization apparatus include an autoclave reactor, a tumbler reactor, and an extruder reactor (kneader, etc.).

As a method for producing a polyamide, a method for producing a polyamide by a batch-type hot-melt polymerization method will be specifically described below, but the method for producing a polyamide is not limited to this.
First, about 40% by mass or more and 60% by mass or less of raw material components for polyamide (combination of dicarboxylic acid and diamine, and at least one selected from the group consisting of lactam and aminocarboxylic acid, if necessary) Prepare an aqueous solution. Then, the aqueous solution is concentrated to about 65% by mass or more and 90% by mass or less in a concentration tank operated at a temperature of 110 ° C. or higher and 180 ° C. or lower and a pressure of about 0.035 MPa or more and 0.6 MPa or less (gauge pressure). to obtain a concentrated solution.
The resulting concentrated solution is then transferred to an autoclave and heating is continued until the pressure in the autoclave is about 1.2 MPa to 2.2 MPa (gauge pressure).
Next, in the autoclave, the pressure is maintained at about 1.2 MPa or more and 2.2 MPa or less (gauge pressure) while removing at least one of water and gas components. Next, when the temperature reaches approximately 220° C. or higher and 260° C. or lower, the pressure is lowered to atmospheric pressure (gauge pressure is 0 MPa). By reducing the pressure in the autoclave to atmospheric pressure and then reducing the pressure as necessary, water produced as a by-product can be effectively removed.
The autoclave is then pressurized with an inert gas such as nitrogen and the polyamide melt is extruded from the autoclave as a strand. The extruded strand is cooled and cut to obtain polyamide pellets.

<Polymer end of polyamide>
The polymer terminal of the polyamide ((A) crystalline polyamide and (B) amorphous polyamide) contained in the polyamide composition of the present embodiment is not particularly limited, but is classified into the following 1) to 4), defined can do.
2) the carboxy terminus; 3) the capped terminus; 4) the other terminus.
1) Amino terminus is a polymer terminus with an amino group ( _-NH2 group) and is derived from a diamine.
2) A carboxy terminal is a polymer terminal having a carboxy group (--COOH group) and is derived from a dicarboxylic acid.
3) Terminals formed by a capping agent are terminals formed when a capping agent is added during polymerization. The terminal blocking agent mentioned above is mentioned as a blocking agent.
4) Other terminals are polymer terminals not classified in 1) to 3) above. Specific examples of other terminals include terminals generated by deammonification of amino terminals, terminals generated by decarboxylation of carboxy terminals, and the like.

<(C) Laser Transmissive Colorant>
(C) The laser light transmissive colorant is a component for coloring the polyamide composition without lowering the transmittance to laser light. That is, (C) the laser light transmitting colorant contains a dye that is transparent to laser light, and specifically, is a colorant that does not have a maximum absorption wavelength in the wavelength range of 900 nm or more and 1100 nm or less.

(C) The laser light transmissive colorant is preferably a black dye that satisfies the properties described later. Examples of such black dyes include naphthalocyanines, aniline black, phthalocyanines, porphyrins, perylenes, quaterylenes, azo dyes, anthraquinones, squaric acid derivatives, immonium dyes, and the like.

(C) Commercially available laser light transmissive colorants include eBIMD (registered trademark) ACW (registered trademark) 9871, eBIND (registered trademark) LTW (registered trademark) 8250, and eBIND, which are colorants manufactured by Orient Chemical Industry Co., Ltd. (registered trademark) LTW (registered trademark) 8701H and the like are exemplified. Also, a black pigment obtained by mixing two or more chromatic pigments may be used.
Among them, the ratio of the minimum light transmittance T% _min to the maximum light transmittance T% _max at a wavelength of 900 nm or more and 1100 nm or less in a molded article having a thickness of 2 mm formed by molding a polyamide composition T% _min / eBIMD (registered trademark) ACW (registered trademark) 9871 or eBIND (registered trademark) LTW (registered trademark) 8701H is preferable from the viewpoint of bringing T% (λ) closer to 1, which is T% _max , eBIND (registered trademark) More preferred is LTW® 8701H.

[(C) Content of laser light transmissive colorant]
(C) The content of the laser light transmissive colorant may be set so that the transmittance of light having a wavelength of 900 nm in a molded article having a thickness of 2 mm obtained by molding the polyamide composition is within the range described later. . Specifically, the content of (C) the laser light transmitting colorant is preferably 0.01% by mass or more and 5.00% by mass or less with respect to the total mass of the polyamide composition. It is preferably at least 3.00% by mass, more preferably at least 0.01% by mass and at most 1.00% by mass, and further preferably at least 0.02% by mass and not more than 0.50% by mass. More preferably, it is most preferably 0.04% by mass or more and 0.10% by mass or less. (C) When the content of the laser light transmitting colorant is at least the above lower limit, the colorability is more excellent, and the design of the product can be further improved. On the other hand, when it is equal to or less than the above upper limit, it is possible to more effectively solve problems during molding due to significant decrease in laser light transmittance, resulting significant decrease in welding strength, and decomposition of pigment components. .

(C) The laser light transmitting colorant may be masterbatched with (A) the crystalline polyamide for use in order to enhance compatibility with the polyamide. For example, a masterbatch can be prepared by diluting (C) the laser light transmitting colorant 50-fold with (A) the crystalline polyamide.
(C) Laser light transmitting colorant mixed with (A) crystalline polyamide or the like, and when compounding a masterbatch diluted 50 times, the amount of the masterbatch to be mixed is (C) Laser light transmitting colorant The content of the content may be in the above range, for example, it can be 0.5% by mass or more and 250.0% by mass or less with respect to the total mass of the polyamide composition, and 1.0% by mass or more It can be 25.0 mass % or less, and can be 2.0 mass % or more and 5.0 mass % or less.

<(D) Inorganic filler>
The polyamide composition of the present embodiment may further contain (D) an inorganic filler in addition to the above components (A) to (C).

Examples of inorganic fillers include, but are not limited to, glass fiber, carbon fiber, calcium silicate fiber, potassium titanate fiber, aluminum borate fiber, clay, glass flakes, talc, kaolin, mica. , hydrotalcite, calcium carbonate, magnesium carbonate, zinc carbonate, zinc oxide, calcium monohydrogen phosphate, wollastonite, silica, zeolite, alumina, boehmite, aluminum hydroxide, titanium oxide, silicon oxide, magnesium oxide, silicic acid Calcium, sodium aluminosilicate, magnesium silicate, ketjen black, acetylene black, furnace black, carbon nanotube, graphite, brass, copper, silver, aluminum, nickel, iron, calcium fluoride, montmorillonite, swelling fluoromica, apatite, etc. are mentioned. These inorganic fillers may be used alone or in combination of two or more.
Among them, from the viewpoint of further improving mechanical strength, from the group consisting of glass fiber, carbon fiber, wollastonite, kaolin, mica, talc, calcium carbonate, magnesium carbonate, potassium titanate fiber, aluminum borate fiber and clay One or more selected are preferred. Among them, more preferably one or more selected from the group consisting of glass fiber, carbon fiber, wollastonite, kaolin, mica, talc, calcium carbonate and clay.

When the inorganic filler is glass fiber or carbon fiber, the number average fiber diameter (d) is preferably 3 μm or more and 30 μm or less, more preferably 3 μm or more and 20 μm or less, still more preferably 3 μm or more and 12 μm or less, and particularly 3 μm or more and 9 μm or less. The thickness is preferably 4 μm or more and 6 μm or less, most preferably.
By setting the number average fiber diameter to the above upper limit or less, it is possible to obtain a polyamide composition having excellent toughness and surface appearance of molded articles. On the other hand, by setting the number-average fiber diameter to the above lower limit or more, a polyamide composition having an excellent balance between cost, powder handling, and physical properties (fluidity, etc.) can be obtained. Furthermore, by setting the number average fiber diameter to 3 μm or more and 9 μm or less, it is possible to obtain a polyamide composition having excellent vibration fatigue properties and slidability.

When the inorganic filler is glass fiber or carbon fiber, its cross section may be circular or flat. Examples of such a flattened cross-section include, but are not limited to, a rectangular shape, an oval shape close to a rectangle, an elliptical shape, and a cocoon shape with a constricted central portion in the longitudinal direction. Here, the "flatness" in the present specification refers to a value represented by d2/d1, where d2 is the major axis of the fiber cross section and d1 is the minor axis of the fiber cross section (perfect circle means flattened ratio is about 1).

When the inorganic filler is glass fiber or carbon fiber, the number average fiber diameter (d) is 3 μm or more and 30 μm or less, and the weight average fiber length ( l) is 100 μm or more and 750 μm or less, and the ratio of the number average fiber diameter (d) to the weight average fiber length (l), that is, the aspect ratio (l/d) is preferably 10 or more and 100 or less. be. The "number average fiber diameter (d)" referred to here is the average value of the major diameter of the fiber cross section (d2 above), and is obtained using the calculation method described later.

In addition, from the viewpoint of reducing warpage of the plate-shaped molded product and improving heat resistance, toughness, low water absorption, and heat aging resistance, the flatness is preferably 1.5 or more, and 1.5 or more and 10.0. The following is more preferable, 2.5 or more and 10.0 or less is still more preferable, more than 3.0 or more and 6.0 or less is particularly preferable, and 3.1 or more and 6.0 or less is most preferable. When the flatness is within the above range, crushing can be more effectively prevented during processing such as mixing with other components, kneading and molding, and the desired effect for the molded product can be obtained more sufficiently. become.

The thickness of the glass fiber or carbon fiber having an oblateness of 1.5 or more is not limited to the following, but the short diameter d1 of the fiber cross section is 0.5 μm or more and 25 μm or less and the long diameter d2 of the fiber cross section is 1.25 μm or more. It is preferably 250 μm or less. More preferably, the minor axis d1 of the fiber cross section is 3.0 μm or more and 25 μm or less, and the major axis d2 of the fiber cross section is 1.25 μm or more and 250 μm or less. When the short diameter (d1) and long diameter (d2) are within the above ranges, the difficulty of fiber spinning can be more effectively avoided, and the strength of the molded product is improved without reducing the contact area with the resin (polyamide). can be further improved.

Glass fiber or carbon fiber having a flatness of 1.5 or more is an orifice plate having a plurality of orifices on the bottom surface, and an orifice plate provided with a convex edge surrounding a plurality of orifice outlets and extending downward from the bottom surface, or An aspect ratio of 1.0 manufactured using any of the modified cross-section glass fiber spinning nozzle tips provided with a plurality of convex edges extending downwardly from the outer peripheral tip of the nozzle tip having one or more orifice holes and having an oblateness of 1. Glass fibers of 5 or more are preferred. Fiber strands of these fibrous reinforcing materials may be used as rovings as they are, or may be used as chopped glass strands after undergoing a cutting process.

Also, the "number average fiber diameter (d)" and "weight average fiber length (l)" in the present specification can be obtained by the following methods. First, the polyamide composition is placed in an electric furnace to incinerate the contained organic matter. 100 or more glass fibers (or carbon fibers) are arbitrarily selected from the residue after the treatment, observed with a scanning electron microscope (SEM), and the fiber diameter (major diameter) of these glass fibers (or carbon fibers) ), the number average fiber diameter can be determined. In addition, the weight average fiber length can be obtained by measuring the fiber length using SEM photographs of the 100 or more glass fibers (or carbon fibers) taken at a magnification of 1000 times.

Also, the glass fiber or carbon fiber may be surface-treated with a silane coupling agent or the like.
Examples of silane coupling agents include, but are not limited to, aminosilanes, mercaptosilanes, epoxysilanes, vinylsilanes, and the like.
Examples of aminosilanes include γ-aminopropyltriethoxysilane, γ-aminopropyltrimethoxysilane, N-β-(aminoethyl)-γ-aminopropylmethyldimethoxysilane and the like.
Mercaptosilanes include, for example, γ-mercaptopropyltrimethoxysilane and γ-mercaptopropyltriethoxysilane.
These silane coupling agents may be used alone or in combination of two or more.
Among them, aminosilanes are preferable as the silane coupling agent.

Also, the glass fiber or carbon fiber may further contain a sizing agent.
Examples of the sizing agent include copolymers and epoxy compounds containing, as structural units, a carboxylic anhydride-containing unsaturated vinyl monomer and an unsaturated vinyl monomer other than the carboxylic anhydride-containing unsaturated vinyl monomer. , polyurethane resins, homopolymers of acrylic acid, copolymers of acrylic acid and other copolymerizable monomers, and salts of these with primary, secondary and tertiary amines. These sizing agents may be used alone or in combination of two or more.
Among them, from the viewpoint of the mechanical strength of the resulting polyamide composition, as a sizing agent, an unsaturated vinyl monomer other than a carboxylic acid anhydride-containing unsaturated vinyl monomer and a carboxylic acid anhydride-containing unsaturated vinyl monomer At least one selected from the group consisting of copolymers, epoxy compounds, and polyurethane resins, each containing as a structural unit, is preferred. Further, it is selected from the group consisting of copolymers and polyurethane resins containing, as structural units, unsaturated vinyl monomers containing carboxylic acid anhydride and unsaturated vinyl monomers other than unsaturated vinyl monomers containing carboxylic acid anhydride. more preferably one or more.

Glass fiber or carbon fiber is produced by applying the above-mentioned sizing agent to the fiber using a known method such as a roller applicator in the known manufacturing process of the fiber, and drying the fiber strand. obtained by a reactive reaction.
The fiber strands may be used as rovings as they are, or may be used as chopped glass strands after undergoing a cutting process.
The sizing agent is preferably added (added) at a solid content of about 0.2% to 3% by mass, preferably 0.3% to 2% by mass, based on the total mass of the glass fibers or carbon fibers. It is more preferable to give (add) the following degree.
When the addition amount of the sizing agent is equal to or higher than the above lower limit as a solid content rate with respect to the total mass of the glass fibers or carbon fibers, the sizing of the fibers can be maintained more effectively. On the other hand, when the amount of the sizing agent added is not more than the above upper limit mass % as a solid content with respect to the total mass of the glass fibers or carbon fibers, the thermal stability of the obtained polyamide composition is further improved.
The strand may be dried after the cutting step, or the strand may be cut after drying.

Inorganic fillers other than glass fiber and carbon fiber include wollastonite, kaolin, mica, talc, calcium carbonate, magnesium carbonate, potassium titanate fiber, and boron, from the viewpoint of improving the strength, rigidity and surface appearance of molded products. Aluminum acid fibers or clay are preferred. Wollastonite, kaolin, mica, talc, calcium carbonate or clay are more preferred. Wollastonite, kaolin, mica or talc are more preferred. Wollastonite, mica or talc are particularly preferred. These inorganic fillers may be used alone or in combination of two or more.

The average particle size of the inorganic filler other than glass fiber and carbon fiber is preferably 0.01 μm or more and 38 μm or less, more preferably 0.03 μm or more and 30 μm or less, from the viewpoint of improving the toughness and the surface appearance of the molded product. It is more preferably 0.05 μm or more and 25 μm or less, even more preferably 0.10 μm or more and 20 μm or less, and particularly preferably 0.15 μm or more and 15 μm or less.
By setting the average particle size of the inorganic filler other than the glass fiber and the carbon fiber to the upper limit value or less, it is possible to obtain a polyamide composition having excellent toughness and surface appearance of a molded product. On the other hand, by setting the average particle size to the above lower limit or more, a polyamide composition having an excellent balance between cost, powder handling, and physical properties (fluidity, etc.) can be obtained.

For acicular inorganic fillers such as wollastonite other than glass fibers and carbon fibers, the average particle size is the number average particle size (hereinafter sometimes simply referred to as "average particle size"). Moreover, when the cross section is not circular, the maximum value of the length is taken as the (number average) particle size.

Regarding the number average particle length of the needle-shaped inorganic filler (hereinafter sometimes simply referred to as "average particle length"), the preferred range of the number average particle size described above and the number average particle size (d) below A numerical range calculated from a preferred range of the aspect ratio (l/d) of the number average particle length (l) to is preferable.

Although it has a needle-like shape, the aspect ratio (l/d) of the number average particle length (l) to the number average particle diameter (d) improves the surface appearance of the molded product, and is suitable for injection molding machines and the like. From the viewpoint of preventing abrasion of metal parts, it is preferably 1.5 or more and 10 or less, more preferably 2.0 or more and 5 or less, and even more preferably 2.5 or more and 4 or less.

In addition, inorganic fillers other than glass fiber and carbon fiber may be subjected to surface treatment using a silane coupling agent, a titanate-based coupling agent, or the like.
Examples of the silane coupling agent include those exemplified for the above glass fiber and carbon fiber.
Among them, aminosilanes are preferable as the silane coupling agent.
Such a surface treatment agent may be applied to the surface of the inorganic filler in advance, or may be added when the polyamide and the inorganic filler are mixed. Moreover, the addition amount of the surface treatment agent is preferably 0.05% by mass or more and 1.5% by mass or less with respect to the total mass of the inorganic filler.

[(D) Content of inorganic filler]
The content of the inorganic filler is preferably 5% by mass or more and 70% by mass or less, more preferably 20% by mass or more and 70% by mass or less, with respect to the total mass of the polyamide composition, and 20% by mass or more and 65% by mass or less. More preferably, 20% by mass or more and 60% by mass or less is more preferable, 25% by mass or more and 60% by mass or less is even more preferable, 30% by mass or more and 60% by mass or less is particularly preferable, and 35% by mass or more and 60% by mass or less is more preferable. More preferably, it is most preferably 35% by mass or more and 50% by mass or less.
When the content of the inorganic filler is at least the above lower limit, the effect of further improving the strength and rigidity of the resulting polyamide composition is exhibited. On the other hand, when the content of the inorganic filler is equal to or less than the above upper limit, it is possible to obtain a polyamide composition having better extrudability and moldability and more excellent laser light transmittance.

<(E) Phosphorus flame retardant>
The polyamide composition of the present embodiment preferably further contains (E) one or more phosphorus-based flame retardants in addition to the above components (A) to (C).
Alternatively, in another embodiment, the polyamide composition further comprises (E) one or more phosphorus-based flame retardants in addition to the above components (A) to (C).
These (E) phosphorus-based flame retardants may be used alone or in combination of two or more.

The phosphorus-based flame retardant is not particularly limited as long as it does not contain a halogen element but contains a phosphorus element. Examples of phosphorus flame retardants include phosphate ester flame retardants, melamine polyphosphate flame retardants, phosphazene flame retardants, phosphinic acid flame retardants, and red phosphorus flame retardants.

Among them, the phosphorus flame retardant is preferably a phosphate ester flame retardant, a melamine polyphosphate flame retardant, a phosphazene flame retardant or a phosphinic acid flame retardant, and particularly preferably a phosphinic acid flame retardant. .

Specific examples of phosphinic acid-based flame retardants include phosphinates such as phosphinates and diphosphinates.

[Phosphinate (1) and Diphosphinate (2)]
Phosphinates include, for example, compounds represented by the following general formula (1) (hereinafter sometimes abbreviated as “phosphinate (1)”) and the like.

Diphosphinates include, for example, diphosphinates represented by the following general formula (2) (hereinafter sometimes abbreviated as “diphosphinate (2)”), and the like.

Furthermore, condensates of these phosphinates and/or diphosphinates may be included.

(In general formula (1), R ¹¹ and R ¹² are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. M ⁿ¹¹⁺ is an n11-valent metal ion M is an element belonging to group 2 or 15 of the periodic table, a transition element, zinc or aluminum n11 is 2 or 3. When n11 is 2 or 3, a plurality of ^R11 and Each R ¹² may be the same or different.
In general formula (2), R ²¹ and R ²² are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. Y ²¹ is an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 10 carbon atoms. M' _x ^m21+ is an m21 valent metal ion. M' is an element belonging to group 2 or group 15 of the periodic table, a transition element, zinc or aluminum. n21 is an integer of 1 or more and 3 or less. When n21 is 2 or 3, multiple R ²¹ , R ²² and Y ²¹ may be the same or different. m21 is 2 or 3; x is 1 or 2; When x is 2, multiple M' may be the same or different. n21, x and m21 are integers satisfying the relational expression 2*n21=m21*x. )

(R ¹¹ , R ¹² , R ²¹ and R ²² )
R ¹¹ , R ¹² , R ²¹ and R ²² are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. When n ¹¹ is 2 or 3, the plurality of R ¹¹ and R ¹² may be the same or different, but are preferably the same for ease of production. When n ²¹ is 2 or 3, multiple R ²¹ and R ²² may be the same or different, but are preferably the same for ease of production. .

The alkyl group may be chain-like or cyclic, but chain-like is preferred. The chain alkyl group may be linear or branched. Linear alkyl groups include, for example, methyl group, ethyl group, n-propyl group, n-butyl group, n-pentyl group, n-hexyl group and the like. Examples of branched chain alkyl groups include 1-methylethyl group, 1-methylpropyl group, 2-methylpropyl group, 1,1-dimethylethyl group, 1-methylbutyl group, 2-methylbutyl group and 3-methylbutyl group. , 1,1-dimethylpropyl group, 1,2-dimethylpropyl group, 2,2-dimethylpropyl group, 1-methylpentyl group, 2-methylpentyl group, 3-methylpentyl group, 4-methylpentyl group, 1,1-dimethylbutyl group, 1,2-dimethylbutyl group, 1,3-dimethylbutyl group, 2,2-dimethylbutyl group, 2,3-dimethylbutyl group, 3,3-dimethylbutyl group, 1- Examples include ethylbutyl group, 2-ethylbutyl group, 1,1,2-trimethylpropyl group and the like.

Examples of aryl groups include phenyl groups and naphthyl groups.

Alkyl groups and aryl groups may have substituents. Examples of substituents on the alkyl group include aryl groups having 6 or more and 10 or less carbon atoms. Examples of substituents on the aryl group include alkyl groups having 1 to 6 carbon atoms.

Specific examples of the alkyl group having a substituent include a benzyl group and the like.

Specific examples of the aryl group having a substituent include a tolyl group and a xylyl group.

Among them, R ¹¹ , R ¹² , R ²¹ and R ²² are preferably alkyl groups having 1 to 6 carbon atoms, more preferably methyl or ethyl groups.

( ^Y21 )
Y ²¹ is an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 10 carbon atoms. When n ²¹ is 2 or 3, the plurality of Y ²¹ may be the same or different, but are preferably the same for ease of production.

The alkylene group may be chain or cyclic, but is preferably chain. The chain alkylene group may be linear or branched. Examples of linear alkylene groups include methylene, ethylene, trimethylene, tetramethylene, pentamethylene, and hexamethylene groups. Examples of branched alkylene groups include 1-methylethylene group and 1-methylpropylene group.

The arylene group includes, for example, a phenylene group and a naphthylene group.

An alkylene group and an arylene group may have a substituent. Examples of substituents on the alkylene group include aryl groups having 6 or more and 10 or less carbon atoms. Examples of substituents on the arylene group include alkyl groups having 1 to 6 carbon atoms.

Specific examples of the alkylene group having a substituent include a phenylmethylene group, a phenylethylene group, a phenyltrimethylene group, a phenyltetramethylene group and the like.

Specific examples of the arylene group having a substituent include methylphenylene group, ethylphenylene group, tert-butylphenylene group, methylnaphthylene group, ethylnaphthylene group, tert-butylnaphthylene group and the like.

Among them, Y ²¹ is preferably an alkylene group having 1 to 10 carbon atoms, more preferably a methylene group or an ethylene group.

(M and M')
M and M' are each independently an ion of an element belonging to Group 2 or Group 15 of the periodic table, an ion of a transition element, a zinc ion, or an aluminum ion. Examples of ions of elements belonging to Group 2 of the periodic table include calcium ions and magnesium ions. Examples of ions of elements belonging to group 15 of the periodic table include bismuth ions.

In addition, when x is 2, the multiple M' may be the same or different, but the same is preferred for ease of production.

Among them, M and M' are preferably calcium, zinc or aluminum, more preferably calcium or aluminum.

(x)
x represents the number of M' and is 1 or 2; x can be appropriately selected according to the type of M' and the number of diphosphinic acids.

(n11 and n21)
n11 represents the number of phosphinic acids and the valence of M, and is 2 or 3; n11 can be appropriately selected according to the type and valence of M.

n21 represents the number of diphosphinic acids and is an integer of 1 or more and 3 or less. n21 can be appropriately selected according to the type and number of M'.

(m21)
m21 represents the valence of M' and is 2 or 3;
n21, x and m21 are integers satisfying the relational expression 2*n21=m21*x.

Specific examples of preferred phosphinates (1) include calcium dimethylphosphinate, magnesium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium ethylmethylphosphinate, magnesium ethylmethylphosphinate, and ethylmethylphosphine. aluminum acid, zinc ethylmethylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum diethylphosphinate, zinc diethylphosphinate, calcium methyl-n-propylphosphinate, magnesium methyl-n-propylphosphinate, methyl-n -aluminum propylphosphinate, zinc methyl-n-propylphosphinate, calcium methylphenylphosphinate, magnesium methylphenylphosphinate, aluminum methylphenylphosphinate, zinc methylphenylphosphinate, calcium diphenylphosphinate, magnesium diphenylphosphinate, diphenyl Examples include aluminum phosphinate and zinc diphenylphosphinate. Among them, as the phosphinate (1), calcium dimethylphosphinate, aluminum dimethylphosphinate, calcium diethylphosphinate, or aluminum diethylphosphinate are preferable because of their excellent flame retardancy, and calcium diethylphosphinate or aluminum diethylphosphinate. is more preferred, and aluminum diethylphosphinate is particularly preferred.

Specific examples of preferred diphosphinates (2) include calcium methanedi(methylphosphinate), magnesium methanedi(methylphosphinate), aluminum methanedi(methylphosphinate), zinc methanedi(methylphosphinate), and benzene-1. ,4-di(methylphosphinate)calcium, benzene-1,4-di(methylphosphinate)magnesium, benzene-1,4-di(methylphosphinate)aluminum, benzene-1,4-di(methylphosphinate) ) zinc and the like.

The method for producing phosphinates is not particularly limited, but includes, for example, the methods described in JP-A-2005-179362, EP-A-699708 and JP-A-08-073729. Specifically, it is produced in an aqueous solution using phosphinic acid and a metal carbonate, metal hydroxide or metal oxide. These are essentially monomeric compounds, but also polymeric phosphinates, which are condensates with a degree of condensation of 1 or more and 3 or less, depending on the reaction conditions and under certain circumstances.

Specific commercial examples of phosphinates include "Exolit OP1230", "Exolit OP1240", "Exolit OP1312", "Exolit OP1314" and "Exolit OP1400" manufactured by Clariant.

(E) The content of the phosphorus-based flame retardant is preferably 5.0 parts by mass or more and 90.0 parts by mass or less with respect to a total of 100 parts by mass of the (A) crystalline polyamide and (B) the amorphous polyamide. , 10.0 to 80.0 parts by mass, more preferably 15.0 to 70.0 parts by mass, and particularly preferably 20.0 to 60.0 parts by mass.
By setting the content of (E) the phosphorus-based flame retardant to at least the above lower limit, it is possible to obtain a resin composition that is more excellent in flame retardancy. On the other hand, by setting the amount of the phosphorus-based flame retardant to the above upper limit or less, it is possible to obtain a resin composition that is more excellent in flame retardancy without impairing the properties of the polyamide composition.

<(F) Other components>
In addition to the above components (A) to (C), the polyamide composition of the present embodiment is one or more selected from the group consisting of lubricants, heat stabilizers, nucleating agents, other polymers, and other additives. (F) may contain other components.

[lubricant]
Examples of lubricants include, but are not limited to, higher fatty acids, higher fatty acid metal salts, higher fatty acid esters, higher fatty acid amides, and the like. Lubricants can also be used as molding modifiers.

(higher fatty acid)
Examples of higher fatty acids include linear or branched saturated or unsaturated aliphatic monocarboxylic acids having 8 to 40 carbon atoms.
Examples of linear saturated aliphatic monocarboxylic acids having 8 to 40 carbon atoms include lauric acid, palmitic acid, stearic acid, behenic acid and montanic acid.
Examples of branched-chain saturated aliphatic monocarboxylic acids having 8 to 40 carbon atoms include isopalmitic acid and isostearic acid.
Examples of linear unsaturated aliphatic monocarboxylic acids having 8 to 40 carbon atoms include oleic acid and erucic acid.
Examples of branched unsaturated aliphatic monocarboxylic acids having 8 to 40 carbon atoms include isoleic acid.
Among them, stearic acid or montanic acid is preferable as the higher fatty acid.

(Higher fatty acid metal salt)
A higher fatty acid metal salt is a metal salt of a higher fatty acid.
Examples of the metal elements of the metal salt include Group 1 elements, Group 2 elements and Group 3 elements of the periodic table, zinc, and aluminum.
Examples of Group 1 elements of the periodic table include sodium and potassium.
Group 2 elements of the periodic table of elements include, for example, calcium and magnesium.
Group 3 elements of the periodic table of elements include, for example, scandium and yttrium.
Among them, elements of groups 1 and 2 of the periodic table or aluminum are preferable, and sodium, potassium, calcium, magnesium or aluminum is more preferable.

Specific examples of higher fatty acid metal salts include calcium stearate, aluminum stearate, zinc stearate, magnesium stearate, calcium montanate, sodium montanate, and calcium palmitate.
Among them, as the higher fatty acid metal salt, a metal salt of montanic acid or a metal salt of stearic acid is preferable.

(higher fatty acid ester)
Higher fatty acid esters are esters of higher fatty acids and alcohols.
As the higher fatty acid ester, an ester of an aliphatic carboxylic acid having 8 to 40 carbon atoms and an aliphatic alcohol having 8 to 40 carbon atoms is preferable.
Examples of aliphatic alcohols having 8 to 40 carbon atoms include stearyl alcohol, behenyl alcohol and lauryl alcohol.
Specific examples of higher fatty acid esters include stearyl stearate and behenyl behenate.

(higher fatty acid amide)
A higher fatty acid amide is an amide compound of a higher fatty acid.
Examples of higher fatty acid amides include stearic acid amide, oleic acid amide, erucic acid amide, ethylenebisstearylamide, ethylenebisoleylamide, N-stearyl stearic acid amide, N-stearyl erucic acid amide and the like.

These higher fatty acids, higher fatty acid metal salts, higher fatty acid esters and higher fatty acid amides may be used alone or in combination of two or more.

The content of the lubricant in the polyamide composition is preferably 0.01% by mass or more and 1% by mass or less, more preferably 0.1% by mass or more and 1% by mass or less, relative to the total mass of the polyamide composition.
When the content of the lubricant is at least the above lower limit value, the moldability of the polyamide composition can be made better, while when it is at most the above upper limit value, the rigidity when formed into a molded product can be made better.

[Heat stabilizer]
Examples of heat stabilizers include, but are not limited to, phenol-based heat stabilizers, phosphorus-based heat stabilizers, amine-based heat stabilizers, groups 3, 4 and 11 to 14 of the periodic table. Metal salts of elements, halides of alkali metals and alkaline earth metals, and the like.

(Phenolic heat stabilizer)
Phenolic heat stabilizers include, but are not limited to, hindered phenol compounds. Hindered phenol compounds have the property of imparting excellent heat resistance and light resistance to resins such as polyamides and fibers.

Examples of the hindered phenol compound include, but are not limited to, N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-butyl-4-hydroxyphenylprop onamide), pentaerythrityl-tetrakis[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionate], N,N'-hexamethylenebis(3,5-di-tert-butyl- 4-hydroxy-hydrocinnamamide), triethylene glycol-bis[3-(3-tert-butyl-5-methyl-4-hydroxyphenyl)propionate], 3,9-bis{2-[3-(3 -tert-butyl-4-hydroxy-5-methylphenyl)propionyloxy]-1,1-dimethylethyl}-2,4,8,10-tetraoxaspiro[5,5]undecane, 3,5-di- tert-butyl-4-hydroxybenzylphosphonate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, and 1,3 , 5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanuric acid and the like.
These hindered phenol compounds may be used alone or in combination of two or more.
In particular, from the viewpoint of improving heat aging resistance, the hindered phenol compound includes N,N'-hexane-1,6-diylbis[3-(3,5-di-tert-butyl-4-hydroxyphenylpropionamide )] is preferred.

When using a phenolic heat stabilizer, the content of the phenolic heat stabilizer in the polyamide composition is preferably 0.01% by mass or more and 1% by mass or less with respect to the total mass of the polyamide composition, and 0.1 % by mass or more and 1 mass % or less is more preferable.
When the content of the phenolic heat stabilizer is within the above range, the heat aging resistance of the polyamide composition can be further improved and the amount of gas generated can be further reduced.

(Phosphorus heat stabilizer)
Examples of phosphorus-based heat stabilizers include, but are not limited to, pentaerythritol-type phosphite compounds, trioctylphosphite, trilaurylphosphite, tridecylphosphite, octyldiphenylphosphite, trisisodecyl Phosphite, phenyldiisodecylphosphite, phenyldi(tridecyl)phosphite, diphenylisooctylphosphite, diphenylisodecylphosphite, diphenyl(tridecyl)phosphite, triphenylphosphite, tris(nonylphenyl)phosphite, tris(2 ,4-di-tert-butylphenyl)phosphite, tris(2,4-di-tert-butyl-5-methylphenyl)phosphite, tris(butoxyethyl)phosphite, 4,4'-butylidene-bis( 3-methyl-6-tert-butylphenyl-tetra-tridecyl)diphosphite, tetra(C12-C15 mixed alkyl)-4,4'-isopropylidene diphenyl diphosphite, 4,4'-isopropylidenebis(2-tert -butylphenyl)-di(nonylphenyl)phosphite, tris(biphenyl)phosphite, tetra(tridecyl)-1,1,3-tris(2-methyl-5-tert-butyl-4-hydroxyphenyl)butanedi Phosphites, tetra(tridecyl)-4,4'-butylidenebis(3-methyl-6-tert-butylphenyl) diphosphite, tetra(C1-C15 mixed alkyl)-4,4'-isopropylidene diphenyl diphosphite, tris (mono, dimixed nonylphenyl) phosphite, 4,4′-isopropylidenebis(2-tert-butylphenyl)-di(nonylphenyl)phosphite, 9,10-di-hydro-9-oxa-10- Phosphaphenanthrene-10-oxide, tris(3,5-di-tert-butyl-4-hydroxyphenyl)phosphite, hydrogenated-4,4'-isopropylidene diphenyl polyphosphite, bis(octylphenyl) -bis(4,4′-butylidenebis(3-methyl-6-tert-butylphenyl))-1,6-hexanediol diphosphite, hexatridecyl-1,1,3-tris(2-methyl-4 -hydroxy-5-tert-butylphenyl)butane triphosphite, tris(4,4'-isopropylidenebis(2-tert-butylphenyl))phosphite, tris(1,3-distearoyloxyisopropyl)phosphite, 2,2-methylenebis(4,6-di-tert-butylphenyl)octylphosphite, 2,2-methylenebis(3-methyl-4,6-di-tert-butylphenyl)2-ethylhexylphosphite, tetrakis ( 2,4-di-tert-butyl-5-methylphenyl)-4,4'-biphenylene diphosphite and tetrakis(2,4-di-tert-butylphenyl)-4,4'-biphenylene diphosphite etc.
These phosphorus-based heat stabilizers may be used alone or in combination of two or more.
Among them, as the phosphorus-based heat stabilizer, pentaerythritol type phosphite compound and tris(2,4-di-tert-butylphenyl ) one or more selected from the group consisting of phosphites.

Examples of pentaerythritol-type phosphite compounds include, but are not limited to, 2,6-di-tert-butyl-4-methylphenyl-phenyl-pentaerythritol diphosphite, 2,6-di- tert-butyl-4-methylphenyl-methyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-2-ethylhexyl-pentaerythritol diphosphite, 2,6-di-tert- Butyl-4-methylphenyl-isodecyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-lauryl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4- Methylphenyl-isotridecyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-stearyl pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl cyclohexyl -pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-benzyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl ethyl cellosolve-pentaerythritol Diphosphite, 2,6-di-tert-butyl-4-methylphenyl-butylcarbitol-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-octylphenyl-pentaerythritol diphosphite phosphites, 2,6-di-tert-butyl-4-methylphenyl-nonylphenyl pentaerythritol diphosphite, bis(2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite, Bis(2,6-di-tert-butyl-4-ethylphenyl) pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-2,6-di-tert-butylphenyl-penta Erythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-2,4-di-tert-butylphenyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methyl Phenyl-2,4-di-tert-octylphenyl-pentaerythritol diphosphite, 2,6-di-tert-butyl-4-methylphenyl-2-cyclohexylphenyl-pentaerythritol diphosphite, 2,6-di -tert-amyl-4-methylphenyl-phenyl pentaerythritol diphosphite, bis(2,6-di-tert-amyl-4-methylphenyl)pentaerythritol diphosphite, and bis(2,6- di-tert-octyl-4-methylphenyl)pentaerythritol diphosphite and the like.
These pentaerythritol-type phosphite compounds may be used alone or in combination of two or more.
Among them, as the pentaerythritol-type phosphite compound, bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite, bis(2 ,6-di-tert-butyl-4-ethylphenyl)pentaerythritol diphosphite, bis(2,6-di-tert-amyl-4-methylphenyl)pentaerythritol diphosphite, and bis(2,6 -di-tert-octyl-4-methylphenyl)pentaerythritol diphosphite, preferably one or more selected from the group consisting of bis(2,6-di-tert-butyl-4-methylphenyl)pentaerythritol diphosphite Fight is more preferred.

When using a phosphorus-based heat stabilizer, the content of the phosphorus-based heat stabilizer in the polyamide composition is preferably 0.01% by mass or more and 1% by mass or less with respect to the total mass of the polyamide composition, and 0.1 % by mass or more and 1 mass % or less is more preferable.
When the content of the phosphorus-based heat stabilizer is within the above range, the heat aging resistance of the polyamide composition can be further improved, and the amount of gas generated can be further reduced.

(Amine heat stabilizer)
Examples of amine heat stabilizers include, but are not limited to, 4-acetoxy-2,2,6,6-tetramethylpiperidine, 4-stearoyloxy-2,2,6,6-tetra methylpiperidine, 4-acryloyloxy-2,2,6,6-tetramethylpiperidine, 4-(phenylacetoxy)-2,2,6,6-tetramethylpiperidine, 4-benzoyloxy-2,2,6, 6-tetramethylpiperidine, 4-methoxy-2,2,6,6-tetramethylpiperidine, 4-stearyloxy-2,2,6,6-tetramethylpiperidine, 4-cyclohexyloxy-2,2,6, 6-tetramethylpiperidine, 4-benzyloxy-2,2,6,6-tetramethylpiperidine, 4-phenoxy-2,2,6,6-tetramethylpiperidine, 4-(ethylcarbamoyloxy)-2,2 ,6,6-tetramethylpiperidine, 4-(cyclohexylcarbamoyloxy)-2,2,6,6-tetramethylpiperidine, 4-(phenylcarbamoyloxy)-2,2,6,6-tetramethylpiperidine, bis (2,2,6,6-tetramethyl-4-piperidyl)-carbonate, bis(2,2,6,6-tetramethyl-4-piperidyl)-oxalate, bis(2,2,6,6-tetra methyl-4-piperidyl)-malonate, bis(2,2,6,6-tetramethyl-4-piperidyl)-sebacate, bis(2,2,6,6-tetramethyl-4-piperidyl)-adipate, bis (2,2,6,6-tetramethyl-4-piperidyl)-terephthalate, 1,2-bis(2,2,6,6-tetramethyl-4-piperidyloxy)-ethane, α,α'-bis (2,2,6,6-tetramethyl-4-piperidyloxy)-p-xylene, bis (2,2,6,6-tetramethyl-4-piperidyl tolylene-2,4-dicarbamate, bis ( 2,2,6,6-tetramethyl-4-piperidyl)-hexamethylene-1,6-dicarbamate, tris(2,2,6,6-tetramethyl-4-piperidyl)-benzene-1,3, 5-tricarboxylate, tris(2,2,6,6-tetramethyl-4-piperidyl)-benzene-1,3,4-tricarboxylate, 1-[2-{3-(3,5-di -tert-butyl-4-hydroxyphenyl)propionyloxy}butyl]-4-[3-(3,5-di-tert-butyl-4-hydroxyphenyl)propionyloxy]2,2,6,6-tetramethyl Piperidine, 1,2,3,4-butanetetracarboxylic acid and 1,2,2,6,6-pentamethyl-4-piperidinol and β,β,β',β'-tetramethyl-3,9-[2 ,4,8,10-tetraoxaspiro(5,5)undecane]condensates with diethanol.
These amine heat stabilizers may be used alone or in combination of two or more.

When using an amine-based heat stabilizer, the content of the amine-based heat stabilizer in the polyamide composition is preferably 0.01% by mass or more and 1% by mass or less with respect to the total mass of the polyamide composition, and 0.1 % by mass or more and 1 mass % or less is more preferable.
When the content of the amine-based heat stabilizer is within the above range, the heat aging resistance of the polyamide composition can be further improved, and the amount of gas generated can be further reduced.

(Metal salts of elements of groups 3, 4 and 11 to 14 of the periodic table)
The metal salts of elements belonging to Groups 3, 4 and 11 to 14 of the periodic table are not particularly limited as long as they are salts of metals belonging to these groups.
Among them, copper salts are preferable from the viewpoint of further improving the heat aging resistance of the polyamide composition. Examples of such copper salts include, but are not limited to, copper halides, copper acetate, copper propionate, copper benzoate, copper adipate, copper terephthalate, copper isophthalate, copper salicylate, copper nicotinate, stearic acid Copper complex salts in which copper is coordinated to copper or a chelating agent can be mentioned.
Examples of copper halides include copper iodide, cuprous bromide, cupric bromide, and cuprous chloride.
Chelating agents include, for example, ethylenediamine and ethylenediaminetetraacetic acid.
These copper salts may be used alone or in combination of two or more.
Among them, the copper salt is preferably one or more selected from the group consisting of copper iodide, cuprous bromide, cupric bromide, cuprous chloride and copper acetate, and consists of copper iodide and copper acetate. One or more selected from the group is more preferable. When the preferred copper salts listed above are used, the heat aging resistance is excellent, and the metal corrosion of the screw and cylinder during extrusion (hereinafter sometimes simply referred to as "metal corrosion") is more effectively suppressed. A polyamide composition is obtained.

When using a copper salt as a heat stabilizer, the content of the copper salt in the polyamide composition is 0.01 mass with respect to the total mass of the polyamide ((A) crystalline polyamide and (B) amorphous polyamide) % or more and 0.60 mass % or less is preferable, and 0.02 mass % or more and 0.40 mass % or less is more preferable.
When the content of the copper salt is within the above range, the heat aging resistance of the polyamide composition can be further improved, and copper deposition and metal corrosion can be more effectively suppressed.

Further, the content concentration of the copper element derived from the above copper salt is, from the viewpoint of improving the heat aging resistance of the polyamide composition, polyamide ((A) crystalline polyamide and (B) amorphous polyamide) 10 ⁶ parts by mass (1,000,000 parts by mass), preferably 10 parts by mass or more and 2000 parts by mass or less, more preferably 30 parts by mass or more and 1500 parts by mass or less, and even more preferably 50 parts by mass or more and 500 parts by mass or less.

(halides of alkali metals and alkaline earth metals)
Halides of alkali metals and alkaline earth metals include, but are not limited to, potassium iodide, potassium bromide, potassium chloride, sodium iodide, sodium chloride, and the like.

These alkali metal and alkaline earth metal halides may be used alone or in combination of two or more.
Among them, the halides of alkali metals and alkaline earth metals are preferably one or more selected from the group consisting of potassium iodide and potassium bromide from the viewpoint of improving heat aging resistance and suppressing metal corrosion. Potassium is more preferred.

When using halides of alkali metals and alkaline earth metals, the content of halides of alkali metals and alkaline earth metals in the polyamide composition is determined by the polyamide ((A) crystalline polyamide and (B) amorphous polyamide ) with respect to 100 parts by mass, preferably 0.05 parts by mass or more and 20 parts by mass or less, and more preferably 0.2 parts by mass or more and 10 parts by mass or less.
When the content of the alkali metal and alkaline earth metal halides is within the above range, the heat aging resistance of the polyamide composition is further improved, and copper precipitation and metal corrosion can be more effectively suppressed. can.

The heat stabilizer components described above may be used alone or in combination of two or more.
Among them, as the heat stabilizer, a hindered phenol compound is preferable from the viewpoint of further improving the heat aging resistance of the polyamide composition.

[Nucleating agent]
A nucleating agent means a substance that, when added, provides at least one of the following effects (1) to (3).
(1) Effect of raising the crystallization peak temperature of the polyamide composition.
(2) The effect of reducing the difference between the extrapolation start temperature and the extrapolation end temperature of the crystallization peak.
(3) Effect of refining the spherulites of the resulting molded product or uniformizing the size thereof.

Examples of the nucleating agent include, but are not limited to, talc, boron nitride, mica, kaolin, silicon nitride, potassium titanate, molybdenum disulfide and the like.
Nucleating agents may be used alone or in combination of two or more.
Among them, talc or boron nitride is preferable as the nucleating agent from the viewpoint of the effect of the nucleating agent.

Moreover, since the effect of the nucleating agent is high, the number average particle diameter of the nucleating agent is preferably 0.01 μm or more and 10 μm or less.
The number average particle size of the nucleating agent can be measured using the following method. First, the molded article is dissolved in a solvent such as formic acid in which polyamide is soluble. Then, for example, 100 or more nucleating agents are arbitrarily selected from the obtained insoluble components. Then, it can be obtained by observing with an optical microscope, a scanning electron microscope, or the like and measuring the particle size.

The content of the nucleating agent in the polyamide composition of the present embodiment is preferably 0.001% by mass or more and 1% by mass or less, and 0.001% by mass or more and 0.5% by mass, relative to the total mass of the polyamide composition. % or less, and more preferably 0.001 mass % or more and 0.09 mass % or less.
By setting the content of the nucleating agent to the above lower limit or more, the heat resistance of the polyamide composition tends to be further improved. A polyamide composition having better toughness is obtained.

[Other polymers]
Other polymers are not particularly limited as long as they are other than polyamide, and examples thereof include polyesters, liquid crystal polyesters, polyphenylene sulfides, polyphenylene ethers, polycarbonates, polyarylates, phenol resins, epoxy resins, and the like. . Examples of polyester include, but are not limited to, polybutylene terephthalate, polytrimethylene terephthalate, polyethylene terephthalate, and polyethylene naphthalate.

The content of other polymers is preferably 1% by mass or more and 30% by mass or less, more preferably 5% by mass or more and 20% by mass or less, and 5% by mass or more and 15% by mass or less, based on the total amount of polyamide in the polyamide composition. is more preferred. When the content of the other polymer is within the above range, it is possible to obtain a polyamide composition that is more excellent in heat resistance and releasability.

[Other additives]
The polyamide composition obtained by the production method of the present embodiment, in addition to the above components, is commonly used in polyamide compositions within a range that does not impair the effects of the polyamide composition obtained by the production method of the present embodiment. Other additives may be included. Other additives include, for example, colorants such as pigments and dyes (including colored masterbatches), non-phosphorous flame retardants, fibrillating agents, fluorescent bleaching agents, plasticizers, antioxidants, ultraviolet absorbers, Examples include antistatic agents, fluidity improvers, spreading agents, and the like.

When the polyamide composition obtained by the production method of the present embodiment contains other additives, the content of the other additives varies depending on the type and the application of the polyamide composition. There is no particular limitation as long as the effect of the polyamide composition obtained by the method is not impaired.

<Method for producing polyamide composition>
The method for producing the polyamide composition of the present embodiment includes a step of melt-kneading the raw material components including (A) the crystalline polyamide, (B) the amorphous polyamide, and (C) the laser light transmitting colorant. It is not particularly limited as long as it is a manufacturing method. For example, it includes a step of melt-kneading the raw material components including (A) the crystalline polyamide, (B) the amorphous polyamide, and (C) the laser light transmissive colorant in an extruder, and the set temperature of the extruder is set to A method of setting the melting peak temperature Tm2+30° C. or lower of the above polyamide composition is preferable.

Alternatively, in another embodiment, as a method for producing a polyamide composition, the above (A) crystalline polyamide, (B) amorphous polyamide, (C) laser light transmitting colorant, (E) phosphorus-based flame retardant It is not particularly limited as long as it is a manufacturing method including a step of melt-kneading raw material components containing. For example, it includes a step of melt-kneading the raw material components including (A) the crystalline polyamide, (B) the amorphous polyamide, (C) the laser-transmitting colorant, and (E) the phosphorus-based flame retardant in an extruder. A preferred method is to set the temperature of the extruder to the melting peak temperature Tm2+30° C. or less of the above polyamide composition.

As a method of melt-kneading the raw material components containing polyamide, for example, the (A) crystalline polyamide, the (B) amorphous polyamide, and the (C) laser light transmitting colorant and other raw materials are put in a tumbler. , Mixing using a Henschel mixer or the like, a method of supplying to a melt kneader and kneading, the above (A) crystalline polyamide in a molten state with a single or twin screw extruder, the above (B) amorphous polyamide and For example, a method of blending (E) other raw materials containing a phosphorus-based flame retardant from a side feeder with the above (C) laser light transmitting colorant. Further, the (A) crystalline polyamide, the (B) amorphous polyamide, and (E) other raw materials containing the phosphorus-based flame retardant are melt-kneaded with a single-screw or twin-screw extruder, cooled and pelletized. , the pellets and (C) the laser light transmitting colorant may be melt-kneaded again by a single-screw or twin-screw extruder.

As for the method of supplying the components constituting the polyamide composition to the melt kneader, all the components may be supplied to the same supply port at once, or the components may be supplied from different supply ports.

The melt-kneading temperature is preferably about 250° C. or higher and 350° C. or lower in terms of resin temperature.
The melt-kneading time is preferably about 0.25 minutes or more and 5 minutes or less.
An apparatus for melt-kneading is not particularly limited, and for example, a known melt-kneader such as a single-screw or twin-screw extruder, a Banbury mixer, or a mixing roll can be used.
The melt kneader is preferably a co-directional twin-screw extruder with a screw diameter of 30 mm or more, and the ratio (L/D) of the barrel length (L) and the screw diameter length (D) of the twin-screw extruder is 35. The above is preferable. When the L/D of the extruder is in the above range, appropriate kneading can be applied during kneading without causing large heat generation, and the domain diameter of the amorphous polyamide can be adjusted to the preferred range in the present application.
In the twin-screw extruder, the screw rotation speed (N) is preferably 350 rpm or more, and the ratio Q/N between the screw rotation speed (N) and the discharge amount (Q) is preferably 1.14 or less. When Q/N is within the above range, appropriate kneading can be applied during kneading without causing large heat generation, and the domain diameter of the amorphous polyamide can be adjusted within the preferred range of the present application.
Further, when adding (D) inorganic filler and (E) phosphorus flame retardant, (A) crystal Polyamide, (B) amorphous polyamide, and (C) laser light-transmitting colorant are dry-blended and then supplied from the upstream side supply port of the twin-screw extruder, and the downstream side first supply port of the twin-screw extruder. It is more preferable to supply (D) an inorganic filler and (E) a phosphorus-based flame retardant.

≪Molded product≫
The molded article of this embodiment is obtained by molding the polyamide composition described above.

By using the polyamide composition described above, the molded article of the present embodiment exhibits good welding strength and appearance when laser-welded, and is excellent in rigidity under atmospheric equilibrium moisture absorption.

The molded article of the present embodiment can be obtained by subjecting the above-described polyamide composition to known molding methods such as press molding, injection molding, gas-assisted injection molding, welding molding, extrusion molding, blow molding, film molding, blow molding, multi-layer molding, It can be obtained by molding using melt spinning or the like.

<Characteristics of molded product>
[Light transmittance of laser light (T%)]
The transmittance (T%) of a laser beam having a wavelength of 900 nm in a molded article having a thickness of 2.0 mm obtained by molding the polyamide composition described above is preferably 40.0% or more, more preferably 50.0% or more. More preferably 55.0% or more, particularly preferably 60.0% or more, most preferably 65.0% or more.
When the laser beam transmittance of a molded article having a thickness of 2.0 mm, which is obtained by molding the polyamide composition, is at least the lower limit, better welding strength and product appearance can be exhibited.
On the other hand, the upper limit of the transmittance (T%) of laser light is preferably as high as possible. can do.

Further, in the case where the above-described polyamide composition contains (E) a phosphorus-based flame retardant, the transmittance (T% ) is preferably 35.0% or more, more preferably 40.0% or more, still more preferably 50.0% or more, particularly preferably 57.5% or more, and most preferably 60.0% or more.
(E) A molded article having a thickness of 1.0 mm, which is formed by molding a polyamide composition containing a phosphorus-based flame retardant, has a laser light transmittance of at least the lower limit value, thereby exhibiting better welding strength and product appearance. can do.
On the other hand, the upper limit of the transmittance (T%) of laser light is preferably as high as possible. 0%, 60.0%, and so on.

As a method for controlling the transmittance of the laser light of the polyamide composition within the above range, for example, a method of controlling the content of (A) the crystalline polyamide and (B) the amorphous polyamide within the above range, ( A) A method of forming domains of (B) amorphous polyamide in crystalline polyamide.

[Wavelength Dependence of Laser Light (T% (λ))]
The ratio of the minimum light transmittance T% _min to the maximum light transmittance T% _max at a wavelength of 900 nm or more and 1100 nm or less in a molded article having a thickness of 2.0 mm obtained by molding the polyamide composition described above. T% _min T% (λ) represented by /T% _max is preferably close to 1, specifically, is preferably 0.700 or more, more preferably 0.750 or more, and further preferably 0.800 or more. , 0.850 or more is particularly preferred, and 0.900 or more is most preferred.
By making the T% (λ) of a molded article having a thickness of 2.0 mm, which is obtained by molding a polyamide composition, not less than the above lower limit, laser can be welded more efficiently regardless of the type of
On the other hand, the closer the upper limit of T%(λ) to 1, the better.

Further, when the above polyamide composition contains (E) a phosphorus-based flame retardant, a molded product having a thickness of 1.0 mm obtained by molding the above polyamide composition has a light transmittance at a wavelength of 900 nm or more and 1100 nm or less. T%(λ), which is represented by the ratio T% _min /T% _max between the minimum value T% _min and the maximum value T% _max of the light transmittance, is preferably close to 1, specifically 0. 850 or more is preferable, 0.875 or more is more preferable, 0.900 or more is still more preferable, 0.970 or more is particularly preferable, and 0.975 or more is most preferable.
(E) T% (λ) of a molded article having a thickness of 1.0 mm, which is obtained by molding a polyamide composition containing a phosphorus-based flame retardant, is equal to or higher than the above lower limit, so that the wavelength generally used in laser welding With a laser of 900 nm or more and 1100 nm or less, welding can be performed more efficiently regardless of the type of laser.
On the other hand, the closer the upper limit of T%(λ) to 1, the better, but it can be set to 0.999, 0.995, 0.990, 0.985, or the like.

≪Laminate≫
The laminate of this embodiment is a laminate in which a laser light transmitting material and a laser light absorbing material are joined together.
The laser beam transmitting material is obtained by molding the polyamide composition of the present embodiment.
The laser light absorber is obtained by molding a composition containing a thermoplastic resin and a laser light absorbing colorant.

In the laminate of the present embodiment, at least part of the joint between the laser light transmitting material and the laser light absorbing material is a laser welded part.

That is, the laminate of this embodiment can also be called a laser-welded body.
In the laser-welded body of the present embodiment, the molded article obtained by molding the polyamide composition functions as a laser light transmitting material. On the other hand, a molded product obtained by molding a composition containing a thermoplastic resin and a laser light-absorbing colorant (hereinafter also referred to as "laser light-absorbing resin composition") generates heat and melts by absorbing laser light. and serves to adhere to the laser light transmitting material.

<Laser light absorbing resin composition>
The laser light-absorbing resin composition contains a thermoplastic resin and a laser light-absorbing dye. In addition to the above components, the laser light-absorbing resin composition contains additives such as inorganic fillers, lubricants, heat stabilizers, phosphorus-based flame retardants, and nucleating agents within a range that does not inhibit the absorption of laser light. It may contain further.
As the inorganic filler, the same ones as those exemplified in the above (D) inorganic filler can be used.
As the phosphorus-based flame retardant, those exemplified in the above (E) phosphorus-based flame retardant can be used.
As the lubricant, heat stabilizer, and nucleating agent, the same ones as those exemplified in the above (F) other components can be used.

[Thermoplastic resin]
Examples of thermoplastic resins include polystyrene resins such as atactic polystyrene, isotactic polystyrene, syndiotactic polystyrene, AS (acrylonitrile-styrene copolymer) resin, and ABS (acrylonitrile-butadiene-styrene copolymer) resin. polyester resins such as polyethylene terephthalate and polybutylene terephthalate; polyamide resins such as polyamide 66, polyamide 6 and polyamide 610; polyether resins such as polycarbonate, polyphenylene ether, polysulfone and polyether sulfone; polyphenylene sulfide, polyoxymethylene Condensation resins such as; acrylic resins such as polyacrylic acid, polyacrylic acid ester, and polymethyl methacrylate; polyolefin resins such as polyethylene, polypropylene, polybutene, and ethylene-propylene copolymer; polyvinyl chloride, polyvinylidene chloride, etc. halogen-containing vinyl compound-based resins; phenolic resins; and epoxy resins.
These thermoplastic resins may be used alone or in combination of two or more.
Among them, polyamide 66, polyamide 6, polyamide 610, polyphenylene ether, polybutylene terephthalate, or polyphenylene sulfide is preferable.

[Laser light absorbing dye]
The laser light-absorbing dye is a dye having an absorption wavelength in the range of the wavelength of the laser light to be irradiated, that is, in the range of 800 nm to 1100 nm in the laminate of the present embodiment, and may be an inorganic pigment. It may be an organic pigment.

Examples of inorganic pigments include black pigments such as carbon black, red pigments such as iron oxide red, orange pigments such as molybdate orange, and white pigments such as titanium oxide.

Examples of organic pigments include yellow pigments, orange pigments, red pigments, blue pigments, and green pigments.

Among them, inorganic pigments are preferred, black inorganic pigments are more preferred, and carbon black is even more preferred, because they generally have a strong hiding power.
These laser light absorbing dyes may be used alone or in combination of two or more.

Carbon black is classified into furnace black, channel black, thermal black, etc. according to its manufacturing method, and is classified into acetylene black, ketjen black, oil black, gas black, etc. according to the difference in raw materials. can be used without particular limitation in the laminate of

The content of the laser light-absorbing dye is preferably 0.01% by mass or more and 30% by mass or less, more preferably 0.01% by mass or more and 10% by mass or less, relative to 100% by mass of the resin component. More preferably, it is 0.01% by mass or more and 1.0% by mass or less.

The softening point of the thermoplastic resin is preferably 180.0° C. or higher and 340.0° C. or lower, more preferably 190.0° C. or higher and 330.0° C. or lower, and 200.0° C. or higher and 320.0° C. It is more preferably 210.0°C or higher and 310.0°C or lower. A softening point means a melting point (Tm2) measured by a differential scanning calorimeter (DSC) in the case of a crystalline resin, and a glass transition temperature (Tg) in the case of an amorphous resin.
By setting the softening point of the thermoplastic resin used for the laser light absorber within the above range, a laser-welded article having excellent welding strength and free from defects such as scorching and having a beautiful product appearance can be obtained.

<Method for manufacturing laser welded body>
The laser-welded body is obtained by laser welding a molded article (laser light transmitting material) obtained by molding the polyamide composition described above and a molded article (laser light absorbing material) obtained by molding the above laser light absorbing resin composition. It can be manufactured by joining with The molding method conforms to the molding method described later.

The shapes of the laser light transmitting material and the laser light absorbing material are not particularly limited, but since molded products are used by joining them by laser welding, it is usually preferable that they have at least a surface (flat or curved surface) that allows surface contact. . In laser welding, the laser light transmitted through the laser light transmitting material is absorbed by the laser light absorbing material and melted, so that the two members can be welded together.

Specifically, the welded portions of the laser light transmitting material and the laser light absorbing material are brought into contact with each other. In this case, it is preferable that both members are brought into surface contact, and flat surfaces, curved surfaces, or a combination of a flat surface and a curved surface may be used. Next, when laser light is irradiated from the laser light transmitting material side, the laser light passes through the laser light transmitting material and is absorbed near the surface of the laser light absorbing material, causing heat generation and melting. At this time, if necessary, a lens may be used to converge the laser light on the interface between the two members. The heat generated in this way also melts the laser light transmitting material due to thermal conduction, forming a molten pool at the interface between the two members, which is then cooled and solidified to join the two members.

The softening point of the laser light absorbing material is preferably close to the softening point of the laser light transmitting material. A softening point means a melting point (Tm2) measured by a differential scanning calorimeter (DSC) in the case of a crystalline resin, and a glass transition temperature (Tg) in the case of an amorphous resin. Specifically, the difference between the softening points of the laser light transmitting material and the laser light absorbing material [(the softening point of the laser light transmitting material) - (the softening point of the laser light absorbing material)] is within ±80.0°C. is preferably within ±70.0°C, more preferably within ±60.0°C, and particularly preferably within ±50.0°C.
When the difference in the softening points of the laser beam transmitting material and the laser beam absorbing material is within the above range, a laser welded body having excellent welding strength and a beautiful product appearance free of defects such as scorch can be obtained.

<Application>
The laser-welded product of the present embodiment is excellent in mechanical properties, welding strength, and product appearance, and thus can be used in various applications.

For example, internal parts of hard disks used in digital home appliances such as personal computers, hard disk DVD (digital video disk) drive recorders, digital video cameras, portable digital music players, mobile phones, etc., and internal parts of various computers and their peripherals. , IC (integrated circuit) tray materials, electrical and electronic parts such as chassis and cabinets for various disc players; electrical parts for motorcycles, electric bicycles and automobiles represented by relay block materials, heat-resistant parts for automobiles; Suitable for heat-resistant parts and the like.
Among others, it is suitable for use as internal parts of hard disks, or electrical components of motorcycles, electric bicycles and automobiles, which require precision molding.

Examples of hard disk internal parts include brackets, latches, combs, spoilers, bushes, mounting plates, hooks, and the like.

Electric parts for motorcycles, electric bicycles and automobiles include, for example, battery cases and battery cases.

Automotive heat-resistant parts include, for example, alternator terminals, alternator connectors, IC regulators, potentiometer bases for light gear, various valves such as exhaust gas valves, engine cooling water joints, carburetor main bodies, carburetor spacers, exhaust gas sensors, cooling water Sensor, oil temperature sensor, brake pad wear sensor, throttle position sensor, crankshaft position sensor, air flow meter, brake pad wear sensor, thermostat base for air conditioner, warm air flow control valve, brush holder for radiator motor, water pump impeller , turbine vanes, wiper motor parts, dust tributors, starter switches, starter relays, wire harnesses for transmissions, window washer nozzles, air conditioner panel switch boards, fuel-related electromagnetic valve coils, fuse connectors, horn terminals, electrical parts Parts such as insulating plates, step motor rotors, brake pistons, solenoid bobbins, ignition device cases, wheel caps, lamp sockets, lamp housings, lamp extensions, lamp reflectors, and the like.

In addition, as heat-resistant parts for office equipment, for example, air conditioner parts, typewriter parts, word processor parts, etc., home and office electrical product parts, office computer related parts, telephone related parts, facsimile related parts, copier related parts parts and the like.

EXAMPLES The present invention will be described below with reference to examples, but the present invention is not limited to the following examples.

EXAMPLES The present invention will be described in detail below with reference to specific examples and comparative examples, but the present invention is not limited to the following examples. First, measurement methods, evaluation methods, and raw materials used in Examples and Comparative Examples are shown below. In this example, 1 kg/cm ² means 0.098 MPa.

≪First test≫
<Constituent>
[(A) Crystalline Polyamide]
A-1: Polyamide 66 (synthesized by the method described later)
A-2: Polyamide 6 (manufactured by Ube Industries, trade name "SF1013A", Mw = 31500, Mw/Mn = 2.2, melting point Tm2 = 230°C)
A-3: Polyamide MXD6 (manufactured by Mitsubishi Engineering Resin Co., Ltd., trade name "Reny 6002, Mw = 40000, Mw / Mn = 2.4, melting point Tm2 = 233 ° C.)
A-4: Polyamide 6T/6I (manufactured by Mitsui Chemicals, trade name "Arlen A3000", Mw = 20000, Mw/Mn = 2.7, melting point Tm2 = 330°C, ΔH = 45J/g)

[(B) amorphous polyamide]
B-1: Polyamide 6I (synthesized by the synthesis method described later)
B-2: Polyamide 6I/6T (manufactured by Ems, model number "G21", content of isophthalic acid units in all dicarboxylic acid units: 70 mol%, Mw = 27000, Mw/Mn = 2.4, ΔH = 0J /g)

[(C) Laser Transmissive Colorant]
C-1: eBIND (registered trademark) LTW (registered trademark)-8071H (manufactured by Orient Chemical Industry Co., Ltd., masterbatch of polyamide 66 and laser light transmitting colorant, dilution ratio 50 times)
C-2: eBIND (registered trademark) ACW (registered trademark)-9871 (manufactured by Orient Chemical Industry Co., Ltd., masterbatch of polyamide 66 and laser light transmitting colorant, dilution ratio 50 times)

[(D) inorganic filler]
D-1: Glass fiber (GF) (manufactured by Nippon Electric Glass, trade name “ECS03T275H”, average fiber diameter 10 μmφ, cut length 3 mm)

[(F) Other components]
F-1: Phenolic heat stabilizer (manufactured by Ciba Specialty Chemicals, trade name "Irganox 1098")
F-2: Calcium montanate (lubricant, manufactured by Clariant, trade name "LICOMONT CAV102")

<Production of Polyamide>
Each method for producing the crystalline polyamide A-1 and the amorphous polyamide B-1 will be described in detail below. The crystalline polyamide A-1 and the amorphous polyamide B-1 obtained by the following production method were dried in a nitrogen stream, adjusted to a moisture content of about 0.2% by mass, and then dried. was used as a raw material for polyamide compositions in Examples and Comparative Examples.

[Synthesis Example 1-1]
(Synthesis of crystalline polyamide A-1 (polyamide 66))
The polymerization reaction of polyamide was carried out as follows by the "hot melt polymerization method".
First, 1500 g of an equimolar salt of adipic acid and hexamethylenediamine was dissolved in 1500 g of distilled water to prepare an equimolar 50% by mass uniform aqueous solution of the raw material monomer. This aqueous solution was charged into an autoclave having an internal volume of 5.4 L, and was purged with nitrogen. Then, while stirring at a temperature of about 110° C. or higher and 150° C. or lower, the solution was concentrated by removing steam gradually until the solution concentration reached 70% by mass. The internal temperature was then raised to 220°C. At this time, the autoclave was pressurized to 1.8 MPa. The mixture was allowed to react for 1 hour while the pressure was maintained at 1.8 MPa by gradually removing water vapor until the internal temperature reached 245°C. The pressure was then reduced over 1 hour. Then, the inside of the autoclave was maintained under a reduced pressure of 650 torr (86.66 kPa) for 10 minutes using a vacuum device. At this time, the final internal temperature of the polymerization was 265°C. Then, it was pressurized with nitrogen, made into a strand from a lower spinneret (nozzle), water-cooled and cut, and discharged in the form of pellets. The pellets were then dried at 100° C. under a nitrogen atmosphere for 12 hours to obtain crystalline polyamide A-1 (polyamide 66).
The resulting crystalline polyamide A-1 (polyamide 66) had Mw (A) = 40000, Mw/Mn = 2.0 and melting point Tm2 = 260°C.

[Synthesis Example 1-2]
(Synthesis of amorphous polyamide B-1 (polyamide 6I))
The polymerization reaction of polyamide was carried out as follows by the "hot melt polymerization method".
First, equimolar salt of isophthalic acid and hexamethylenediamine: 1500 g, and 1.5 mol % excess adipic acid and 0.5 mol % acetic acid with respect to all equimolar salt components, distilled water: 1500 g to prepare an equimolar 50% by mass uniform aqueous solution of the raw material monomer. Then, while stirring at a temperature of about 110° C. or higher and 150° C. or lower, the solution was concentrated by removing steam gradually until the solution concentration reached 70% by mass. The internal temperature was then raised to 220°C. At this time, the autoclave was pressurized to 1.8 MPa. The mixture was allowed to react for 1 hour while the pressure was maintained at 1.8 MPa by gradually removing water vapor until the internal temperature reached 245°C. The pressure was then reduced over 30 minutes. Then, the inside of the autoclave was maintained under a reduced pressure of 650 torr (86.66 kPa) for 10 minutes using a vacuum device. At this time, the final internal temperature of the polymerization was 265°C. Then, it was pressurized with nitrogen, made into a strand from a lower spinneret (nozzle), water-cooled and cut, and discharged in the form of pellets. The pellets were then dried at 100° C. under a nitrogen atmosphere for 12 hours to obtain amorphous polyamide B-1 (polyamide 6I).
In the obtained amorphous polyamide B-1 (polyamide 6I), the content of isophthalic acid units in dicarboxylic acid units was 100 mol %. Mw (B) = 20000 and Mw/Mn = 2.0.

<Method for measuring physical properties>
Using the raw polyamide and the polyamide composition after adjusting the water content, the following various physical properties were measured.

[Physical properties 1-1]
(Molecular weight and molecular weight distribution of polyamide composition)
Mw (weight average molecular weight) and Mn (number average molecular weight) are measured using a gel permeation chromatograph (GPC) (manufactured by Tosoh Corporation, HLC-8020) and a hexafluoroisopropanol solvent, PMMA (polymethyl methacrylate ) was measured in terms of a standard sample (manufactured by Polymer Laboratories). From that value, the molecular weight distribution Mw/Mn was calculated.

[Physical properties 1-2]
(Melting peak temperature Tm2 (melting point) and crystallization enthalpy ΔH)
It was measured using a Diamond-DSC manufactured by PERKIN-ELMER in accordance with JIS-K7121. Specifically, it was measured as follows.
First, in a nitrogen atmosphere, about 10 mg of a sample was heated from room temperature to 300° C. or more and 350° C. or less depending on the melting point of the sample at a temperature elevation rate of 20° C./min. The highest peak temperature of the endothermic peak (melting peak) appearing at this time was defined as Tm1 (°C). The temperature was then held at the maximum temperature of the ramp for 2 minutes. At this maximum temperature the polyamide was in the molten state. Then, the temperature was lowered to 30°C at a temperature lowering rate of 20°C/min. The exothermic peak appearing at this time was taken as the crystallization peak, and the crystallization peak area was taken as the crystallization enthalpy ΔH (J/g). Thereafter, the temperature was maintained at 30° C. for 2 minutes, and then the temperature was raised from 30° C. to 280° C. or more and 300° C. or less depending on the melting point of the sample at a rate of temperature increase of 20° C./min. The maximum peak temperature of the endothermic peak (melting peak) appearing at this time was defined as the melting point Tm2 (°C).

[Physical properties 1-3]
(Glass transition temperature Tg)
The glass transition temperature Tg (° C.) was measured according to JIS-K7121 using a Diamond-DSC manufactured by PERKIN-ELMER. Measurement conditions were as follows: a sample in a molten state obtained by melting polyamide on a hot stage (EP80 manufactured by Mettler) was quenched using liquid nitrogen and solidified to obtain a measurement sample. Using 10 mg of the sample, the temperature was raised from 30° C. to 350° C. at a heating rate of 20° C./min, and the glass transition temperature Tg (° C.) was measured.

[Production of test piece]
For each polyamide composition, using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., trade name "NEX50III-5EG"), an injection speed of 45 mm / sec, a screw rotation speed of 150 rpm, a mold temperature of 80 ° C., and a cylinder temperature. The melting point (Tm2) of the polyamide composition was set to +20°C, and a flat plate molded piece (60 mm x 60 mm, thickness 2.0 mm) was produced as a test piece.

[Physical properties 1-4]
(Laser beam light transmittance (T%))
The laser light transmittance of the obtained test piece at a wavelength of 900 nm or more and 1100 nm or less was measured at wavelength intervals of 1.0 nm using a spectrophotometer "V-670" manufactured by JASCO Corporation.

Regarding the wavelength dependence of laser light (T% (λ)), the minimum value (T% (min) in the laser light transmittance of the obtained test piece at 900 nm or more and 1100 nm or less, and the maximum value (T% (max) ) divided by T% (min) / T% (max) was calculated and obtained.Regarding the polyamide compositions of Examples 1-1 to 1-10 and Comparative Examples 1-1 to 1-5, any Also, T % (min) was the light transmittance at a wavelength of 900 nm, and T (max) was the light transmittance at a wavelength of 1100 nm.

[Physical properties 1-5]
(Domain size of amorphous polyamide)
After staining the obtained test piece with ruthenium tetroxide, an ultra-thin section was cut out and subjected to morphology observation with a transmission electron microscope (manufactured by Hitachi, Ltd., H-7100 type transmission electron microscope). The domain size of (B) amorphous polyamide dispersed in polyamide was measured. The observable particle length was measured to obtain the dispersed particle size distribution, and the 50% cumulative value of the obtained dispersed particle size distribution was taken as the number average particle size.

<Evaluation method>
Molded articles obtained from each polyamide composition were evaluated by the following evaluation methods.

[Evaluation 1-1]
(laser welding strength)
1. Production of laser welded product (1) Production of laser light transmitting material Each polyamide composition is injected using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., trade name “NEX50III-5EG”), and the cylinder temperature is adjusted to that of the polyamide composition. The melting point (Tm2) was set to +20°C, and a flat plate (60 x 60 x 2 mm) was molded at a mold temperature of 80°C to obtain a laser light transmitting material.

(2) Production of laser light absorbing material Next, a thermoplastic resin selected from polyamide (PA), polyphenylene ether (PPE), polybutylene terephthalate (PBT), and polyphenylene sulfide (PPS), and a laser light absorbing material After the colorant is dry blended, it is supplied from the upstream supply port of the twin-screw extruder, the inorganic filler is supplied from the downstream first supply port of the twin-screw extruder, and the melt-kneaded product extruded from the die head is extruded into strands. The mixture was cooled in a form and pelletized to obtain pellets of the laser light-absorbing resin composition. The cylinder temperature of the twin-screw extruder was set to the melting point (Tm2) of the thermoplastic resin +20°C, and the operation was performed at a rotation speed of 300 rpm and a discharge rate of 400 kg/hour. The obtained pellets were molded by the same molding method as for the laser light transmitting material to obtain the laser light absorbing material.

Details of the raw materials are as follows.

(Thermoplastic resin)
Polyamide (PA): crystalline polyamide A-1 (polyamide 66)
Polyphenylene ether (PPE): manufactured by Asahi Kasei Corporation, Mw = 30000
Polybutylene terephthalate (PBT): manufactured by Toray Industries, Inc., trade name "1401 X06"
Polyphenylene sulfide (PPS): manufactured by DIC, trade name "FZ-2100"

(Laser light absorbing colorant)
Laser light absorbing colorant: carbon black (manufactured by Mitsubishi Chemical Corporation, primary particle size 27 nm)

(Inorganic filler)
Inorganic filler: inorganic filler D-1 (glass fiber (GF) (manufactured by Nippon Electric Glass, trade name “ECS03T275H”, average fiber diameter 10 μmφ, cut length 3 mm))

Further, the mixing ratio of each raw material was set to thermoplastic resin:laser light absorbing colorant:inorganic filler=55:5:40 in terms of mass ratio.

(3) Laser welding of laser light transmitting material and laser light absorbing material With the flat plates of the laser light transmitting material and laser light absorbing material (three types) fixed, the head of the laser welding machine is moved at a scanning speed of 62.8 mm/ A laser was irradiated so as to draw a circle with a scanning diameter of φ20 mm in sec, and at the same time, the portion was cooled with air to prepare a laser-welded body. A semiconductor laser (wavelength: 940 nm) and a fiber laser (wavelength: 1060 nm) were used as laser light sources. In addition, the laser output was appropriately set according to the welding strength and the product burnt condition.

2. Evaluation of Laser Welding Strength The welded state after welding of the laser welded bodies obtained by the above-described method was checked and evaluated according to the following criteria.

(Evaluation criteria)
⊚: Both the welded state and the appearance are good, and the base material is broken in the peeling evaluation, and the welded portion cannot be peeled off.
◯: Good welding state, the welded portion was broken in the evaluation of peeling, but welding traces were observed.
Δ: It is welded, but the welded part is easily peeled off in the peel test, and the weld marks are unclear.
x: No welding.

[Evaluation 1-2]
Appearance of Laser-Welded Product The product appearance of the laser-welded product obtained by the method described in "Evaluation 1-1" above was visually evaluated and evaluated according to the following criteria.

(Evaluation criteria)
⊚: No discoloration is observed, and the surface gloss is excellent.
◯: No discoloration is observed, but the surface gloss is poor.
Δ: Discoloration is observed in part of the product, and the surface gloss is poor.
x: Many discolorations are observed on the product, and the surface gloss is poor.

[Evaluation 1-3]
(Plasticization time)
For each polyamide composition, using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., trade name "NEX50III-5EG"), the cylinder temperature was set to the melting point (Tm2) of the polyamide composition + 20 ° C., and the mold temperature was set. 100 shots were molded under injection molding conditions of 80° C., injection time of 15 seconds, and cooling time of 10 seconds to obtain an ISO test piece in accordance with ISO3167. The average plasticizing time of 100 shots was calculated.

[Evaluation 1-4]
(Release time)
For each polyamide composition, using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., trade name "NEX50III-5EG"), injection time 10 seconds, screw rotation speed 200 rpm, mold temperature 80 ° C., cylinder temperature polyamide The melting point (Tm2) of the composition is set to +20°C, and the injection pressure and injection speed are appropriately adjusted so that the filling time is in the range of 0.8 ± 0.1 seconds. 3 mm thick) were manufactured. At that time, the shortest cooling time during which the molded piece automatically dropped from the mold continuously for 10 shots was taken as the release time.

[Evaluation 1-5]
(Flexural modulus under atmospheric equilibrium moisture absorption (flexural modulus (wet)))
For each polyamide composition, an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., trade name "NEX50III-5EG") was used to prepare an ISO dumbbell with a thickness of 4 mm in accordance with ISO 3167 and used as a test piece. The obtained test piece was allowed to stand in an atmosphere of constant temperature and humidity (23° C., 50 RH %) to reach water absorption equilibrium, and then the flexural modulus was measured according to ISO178.

<Production of Polyamide Composition>
[Examples 1-1 to 10 and Comparative Examples 1-1, 1-3 to 1-5]
(Production of polyamide compositions PA-a1 to PA-a10 and PA-b1, PA-b3 to PA-b5)
(A) crystalline polyamide, (B) amorphous polyamide, (C) laser light transmitting colorant, (D) inorganic filler, and (F) other components are used in the types and proportions shown in the tables below. A polyamide composition was produced as follows.

The raw material polyamide ((A) crystalline polyamide and (B) amorphous polyamide) was dried in a nitrogen stream to adjust the moisture content to about 0.2% by mass, and then used as a raw material for the polyamide composition. board.

The polyamide composition production equipment includes a twin-screw extruder (manufactured by Toshiba Machine Co., Ltd., product name "TEM-58SX" (L / D = 53.8)) and a single-screw extruder (manufactured by Tanabe Plastics Machinery, product The name "S65", (L/D=36)) was used.

In the twin-screw extruder, the temperature from the upstream supply port to the die was set to the melting point Tm2 + 20 ° C. of each (A) crystalline polyamide produced in the above production example, the screw rotation speed was 350 rpm, and the discharge rate was 400 kg / h (Q /N=1.14). In the single-screw extruder, the temperature from the upstream supply port to the die was set to the melting point Tm2 of (A) the crystalline polyamide +20°C, the screw rotation speed was set to 150 rpm, and the discharge rate was set to 50 kg/h.

(A) crystalline polyamide, (B) amorphous polyamide, and (F) other components are dry-blended so that the types and proportions shown in the following tables are obtained, and then the upstream supply port of the twin-screw extruder. supplied from the downstream first supply port of the twin-screw extruder, (D) inorganic filler is supplied, and the melt-kneaded product extruded from the die head is cooled in a strand and pelletized to pelletize the polyamide composition. got The pellets thus obtained and (C) the laser-transmitting colorant are dry-blended, then fed from the upstream feed port of the single-screw extruder, and the melt-kneaded product extruded from the die head is cooled in the form of strands and pelletized. to obtain pellets of the desired polyamide composition (laser ray transmitting polyamide resin composition).
The obtained polyamide composition pellets were dried in a nitrogen stream to reduce the water content in the polyamide composition to 500 ppm or less.

[Comparative Example 1-2]
(Production of polyamide composition PA-b2)
A polyamide composition was obtained in the same manner as in Comparative Example 1-1, except that the obtained pellets were placed in an oven set at 120° C. for 1 hour for annealing.

The measurement results and evaluation results of the physical properties of each polyamide composition are shown in the following tables.

From Tables 1 to 6, (A) a crystalline polyamide, (B) an amorphous polyamide, and (C) containing a laser light transmitting colorant, and (B) the amount of the amorphous polyamide contained in the polyamide composition 10.0% by mass or more and 50.0% by mass or less with respect to the total polyamide amount in the medium, and (B) the amorphous polyamide is dispersed in the (A) crystalline polyamide to form domains With the polyamide compositions PA-a1 to PA-a10 (Examples 1-1 to 1-10), laser-welded bodies having excellent welding strength and product appearance were obtained, and molding was performed from the viewpoint of plasticization time and mold release time. The flexural modulus of moisture absorption at atmospheric equilibrium when formed into a molded article was as high as 10.0 GPa or more.

In addition, in the polyamide compositions PA-a1 to PA-a9 (Examples 1-1 to 1-9) having a wavelength dependence (T% (λ)) of laser light of 0.900 or more, at wavelengths of 940 nm and 1060 nm It was found that the laser welding strength is particularly good and that it can be used with various types of laser light sources.

On the other hand, the polyamide compositions PA-b1 and PA-b2 (Comparative Examples 1-1 and 1-2) containing no amorphous polyamide (B) were inferior in product appearance when formed into laser-welded bodies. Further, the polyamide composition PA-b1 (Comparative Example 1-1) had a long plasticizing time of 12.0 seconds, was inferior in moldability, and was also inferior in flexural modulus under atmospheric equilibrium moisture absorption.

(B) In the polyamide composition PA-b3 (Comparative Example 1-3) in which the content of the amorphous polyamide is more than 50.0% by mass relative to the mass of the total polyamide in the polyamide composition, the release time was as long as 30.0 seconds, resulting in inferior moldability. In addition, the laser-welded body was found to be burnt, and the appearance of the product was poor.

Polyamide composition PA-b4 (Comparative Example 1-4) using a crystalline polyamide having a melting point of more than 290° C. was inferior in welding strength and product appearance when formed into a laser-welded body. In addition, the plasticizing time was 15.0 seconds and the mold releasing time was long at 20.0 seconds, resulting in poor moldability.

(B) The polyamide composition PA-b5 (Comparative Example 1-5), which does not contain an amorphous polyamide, is inferior in welding strength and product appearance when used as a laser-welded body, and furthermore, has a laser welding strength at a wavelength of 1060 nm. As a result, the laser welding strength at a wavelength of 940 nm was inferior, and the type of laser beam used in laser welding was limited. In addition, the plasticizing time was as long as 12.3 seconds, the moldability was poor, and the flexural modulus under moisture absorption at atmospheric equilibrium was also poor.

≪Second test≫
<Constituent>
[(A) Crystalline Polyamide]
A-1: Polyamide 66 (synthesized by the method described later)
A-2: Polyamide 6 (manufactured by Ube Industries, trade name "SF1013A", Mw = 31500, Mw/Mn = 2.2, melting point Tm2 = 230°C)
A-3: Polyamide MXD6 (manufactured by Mitsubishi Engineering Resin Co., Ltd., trade name "Reny 6002, Mw = 40000, Mw / Mn = 2.4, melting point Tm2 = 233 ° C.)
A-4: Polyamide 6T/6I (manufactured by Mitsui Chemicals, trade name "Arlen A3000", Mw = 20000, Mw/Mn = 2.7, melting point Tm2 = 330°C, ΔH = 45J/g)

[(B) amorphous polyamide]
B-1: Polyamide 6I (synthesized by the synthesis method described later)
B-2: Polyamide 6I/6T (manufactured by Ems, model number "G21", content of isophthalic acid units in all dicarboxylic acid units: 70 mol%, Mw = 27000, Mw/Mn = 2.4, ΔH = 0J /g)

[(C) Laser Transmissive Colorant]
C-1: eBIND (registered trademark) LTW (registered trademark)-8071H (manufactured by Orient Chemical Industry Co., Ltd., masterbatch of polyamide 66 and laser light transmitting colorant, dilution ratio 50 times)
C-2: eBIND (registered trademark) ACW (registered trademark)-9871 (manufactured by Orient Chemical Industry Co., Ltd., masterbatch of polyamide 66 and laser light transmitting colorant, dilution ratio 50 times)

[(D) inorganic filler]
D-1: Glass fiber (GF) (manufactured by Nippon Electric Glass, trade name “ECS03T275H”, average fiber diameter 10 μmφ, cut length 3 mm)

[(E) Phosphorus flame retardant]
E-1: Phosphinic acid-based flame retardant aluminum diethylphosphinate (manufactured by Clariant, trade name "Exolit OP1230")

[(F) Other components]
F-1: Phenolic heat stabilizer (manufactured by Ciba Specialty Chemicals, trade name "Irganox 1098")
F-2: Calcium montanate (lubricant, manufactured by Clariant, trade name "LICOMONT CAV102")

<Production of Polyamide>
Each method for producing the crystalline polyamide A-1 and the amorphous polyamide B-1 will be described in detail below. The crystalline polyamide A-1 and the amorphous polyamide B-1 obtained by the following production method were dried in a nitrogen stream, adjusted to a moisture content of about 0.2% by mass, and then dried. was used as a raw material for polyamide compositions in Examples and Comparative Examples.

[Synthesis Example 2-1]
(Synthesis of crystalline polyamide A-1 (polyamide 66))
The polymerization reaction of polyamide was carried out as follows by the "hot melt polymerization method".
First, 1500 g of an equimolar salt of adipic acid and hexamethylenediamine was dissolved in 1500 g of distilled water to prepare an equimolar 50% by mass uniform aqueous solution of the raw material monomer. This aqueous solution was charged into an autoclave having an internal volume of 5.4 L, and was purged with nitrogen. Then, while stirring at a temperature of about 110° C. or higher and 150° C. or lower, the solution was concentrated by removing steam gradually until the solution concentration reached 70% by mass. The internal temperature was then raised to 220°C. At this time, the autoclave was pressurized to 1.8 MPa. The mixture was allowed to react for 1 hour while the pressure was maintained at 1.8 MPa by gradually removing water vapor until the internal temperature reached 245°C. The pressure was then reduced over 1 hour. Then, the inside of the autoclave was maintained under a reduced pressure of 650 torr (86.66 kPa) for 10 minutes using a vacuum device. At this time, the final internal temperature of the polymerization was 265°C. Then, it was pressurized with nitrogen, made into a strand from a lower spinneret (nozzle), water-cooled and cut, and discharged in the form of pellets. The pellets were then dried at 100° C. under a nitrogen atmosphere for 12 hours to obtain crystalline polyamide A-1 (polyamide 66).
The resulting crystalline polyamide A-1 (polyamide 66) had Mw (A) = 40000, Mw/Mn = 2.0 and melting point Tm2 = 260°C.

[Synthesis Example 2-2]
(Synthesis of amorphous polyamide B-1 (polyamide 6I))
The polymerization reaction of polyamide was carried out as follows by the "hot melt polymerization method".
First, equimolar salt of isophthalic acid and hexamethylenediamine: 1500 g, and 1.5 mol % excess adipic acid and 0.5 mol % acetic acid with respect to all equimolar salt components, distilled water: 1500 g to prepare an equimolar 50% by mass uniform aqueous solution of the raw material monomer. Then, while stirring at a temperature of about 110° C. or higher and 150° C. or lower, the solution was concentrated by removing steam gradually until the solution concentration reached 70% by mass. The internal temperature was then raised to 220°C. At this time, the autoclave was pressurized to 1.8 MPa. The mixture was allowed to react for 1 hour while the pressure was maintained at 1.8 MPa by gradually removing water vapor until the internal temperature reached 245°C. The pressure was then reduced over 30 minutes. Then, the inside of the autoclave was maintained under a reduced pressure of 650 torr (86.66 kPa) for 10 minutes using a vacuum device. At this time, the final internal temperature of the polymerization was 265°C. Then, it was pressurized with nitrogen, made into a strand from a lower spinneret (nozzle), water-cooled and cut, and discharged in the form of pellets. The pellets were then dried at 100° C. under a nitrogen atmosphere for 12 hours to obtain amorphous polyamide B-1 (polyamide 6I).
In the obtained amorphous polyamide B-1 (polyamide 6I), the content of isophthalic acid units in dicarboxylic acid units was 100 mol %. Mw (B) = 20000 and Mw/Mn = 2.0.

<Method for measuring physical properties>
Using the raw polyamide and the polyamide composition after adjusting the water content, the following various physical properties were measured.

[Physical properties 2-1]
(Molecular weight and molecular weight distribution of polyamide composition)
Mw (weight average molecular weight) and Mn (number average molecular weight) are measured using a gel permeation chromatograph (GPC) (manufactured by Tosoh Corporation, HLC-8020) and a hexafluoroisopropanol solvent, PMMA (polymethyl methacrylate ) was measured in terms of a standard sample (manufactured by Polymer Laboratories). From that value, the molecular weight distribution Mw/Mn was calculated.

[Physical properties 2-2]
(Melting peak temperature Tm2 (melting point) and crystallization enthalpy ΔH)
It was measured using a Diamond-DSC manufactured by PERKIN-ELMER in accordance with JIS-K7121. Specifically, it was measured as follows.
First, in a nitrogen atmosphere, about 10 mg of a sample was heated from room temperature to 300° C. or more and 350° C. or less depending on the melting point of the sample at a temperature elevation rate of 20° C./min. The highest peak temperature of the endothermic peak (melting peak) appearing at this time was defined as Tm1 (°C). The temperature was then held at the maximum temperature of the ramp for 2 minutes. At this maximum temperature the polyamide was in the molten state. Then, the temperature was lowered to 30°C at a temperature lowering rate of 20°C/min. The exothermic peak appearing at this time was taken as the crystallization peak, and the crystallization peak area was taken as the crystallization enthalpy ΔH (J/g). Thereafter, the temperature was maintained at 30° C. for 2 minutes, and then the temperature was raised from 30° C. to 280° C. or more and 300° C. or less depending on the melting point of the sample at a rate of temperature increase of 20° C./min. The maximum peak temperature of the endothermic peak (melting peak) appearing at this time was defined as the melting point Tm2 (°C).

[Physical properties 2-3]
(Glass transition temperature Tg)
The glass transition temperature Tg (° C.) was measured according to JIS-K7121 using a Diamond-DSC manufactured by PERKIN-ELMER. Measurement conditions were as follows: a sample in a molten state obtained by melting polyamide on a hot stage (EP80 manufactured by Mettler) was quenched using liquid nitrogen and solidified to obtain a measurement sample. Using 10 mg of the sample, the temperature was raised from 30° C. to 350° C. at a heating rate of 20° C./min, and the glass transition temperature Tg (° C.) was measured.

[Production of test piece]
For each polyamide composition, using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., trade name "NEX50III-5EG"), an injection speed of 45 mm / sec, a screw rotation speed of 150 rpm, a mold temperature of 80 ° C., and a cylinder temperature. The melting point (Tm2) of the polyamide composition was set to +20°C, and a flat plate molded piece (60 mm x 60 mm, thickness 1.0 mm) was produced as a test piece.

[Physical properties 2-4]
(Laser beam light transmittance (T%))
The laser light transmittance of the obtained test piece at a wavelength of 900 nm or more and 1100 nm or less was measured at wavelength intervals of 1.0 nm using a spectrophotometer "V-670" manufactured by JASCO Corporation.

Regarding the wavelength dependence of laser light (T% (λ)), the minimum value (T% (min) in the laser light transmittance of the obtained test piece at 900 nm or more and 1100 nm or less, and the maximum value (T% (max) ) divided by T% (min) / T% (max) was calculated and obtained.Regarding the polyamide compositions of Examples 2-1 to 2-10 and Comparative Examples 2-1 to 2-5, any Also, T % (min) was the light transmittance at a wavelength of 900 nm, and T (max) was the light transmittance at a wavelength of 1100 nm.

[Physical properties 2-5]
(Domain size of amorphous polyamide)
After staining the obtained test piece with ruthenium tetroxide, an ultra-thin section was cut out and subjected to morphology observation with a transmission electron microscope (manufactured by Hitachi, Ltd., H-7100 type transmission electron microscope). The domain size of (B) amorphous polyamide dispersed in polyamide was measured. The observable long diameter of the particles was measured to obtain the dispersed particle size distribution, and the 50% cumulative value of the obtained dispersed particle size distribution was taken as the number average particle size.

<Evaluation method>
Molded articles obtained from each polyamide composition were evaluated by the following evaluation methods.

[Evaluation 2-1]
(laser welding strength)
1. Production of laser welded product (1) Production of laser light transmitting material Each polyamide composition is injected using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., trade name “NEX50III-5EG”), and the cylinder temperature is adjusted to that of the polyamide composition. The melting point (Tm2) was set to +20°C, and a flat plate (60 x 60 x 1 mm) was molded at a mold temperature of 80°C to obtain a laser light transmitting material.

(2) Production of laser light absorbing material Next, a thermoplastic resin selected from polyamide (PA), polyphenylene ether (PPE), polybutylene terephthalate (PBT), and polyphenylene sulfide (PPS), and a laser light absorbing material After dry blending the colorant, it is supplied from the upstream side supply port of the twin-screw extruder, and the phosphorus-based flame retardant and inorganic filler are supplied from the downstream side first supply port of the twin-screw extruder, and extruded from the die head. The resulting melt-kneaded product was cooled in the form of strands and pelletized to obtain pellets of the laser light-absorbing resin composition. The cylinder temperature of the twin-screw extruder was set to the melting point (Tm2) of the thermoplastic resin +20°C, and the operation was performed at a rotation speed of 300 rpm and a discharge rate of 400 kg/hour. The obtained pellets were molded by the same molding method as for the laser light transmitting material to obtain the laser light absorbing material.

Details of the raw materials are as follows.

(Thermoplastic resin)
Polyamide (PA): crystalline polyamide A-1 (polyamide 66)
Polyphenylene ether (PPE): manufactured by Asahi Kasei Corporation, Mw = 30000
Polybutylene terephthalate (PBT): manufactured by Toray Industries, Inc., trade name "1401 X06"
Polyphenylene sulfide (PPS): manufactured by DIC, trade name "FZ-2100"

(Laser light absorbing colorant)
Laser light absorbing colorant: carbon black (manufactured by Mitsubishi Chemical Corporation, primary particle size 27 nm)

(Inorganic filler)
Inorganic filler: inorganic filler D-1 (glass fiber (GF) (manufactured by Nippon Electric Glass, trade name “ECS03T275H”, average fiber diameter 10 μmφ, cut length 3 mm))

(Phosphorus flame retardant)
Phosphinic acid-based flame retardant aluminum diethylphosphinate (manufactured by Clariant, trade name "Exolit OP1230")

Further, the blending ratio of each raw material was set to thermoplastic resin:laser light absorbing colorant:phosphorus flame retardant:inorganic filler=57:5:18:20 in terms of mass ratio.

(3) Laser welding of laser light transmitting material and laser light absorbing material With the flat plates of the laser light transmitting material and laser light absorbing material (three types) fixed, the head of the laser welding machine is moved at a scanning speed of 62.8 mm/ A laser was irradiated so as to draw a circle with a scanning diameter of φ20 mm in sec, and at the same time, the portion was cooled with air to prepare a laser-welded body. A semiconductor laser (wavelength: 940 nm) and a fiber laser (wavelength: 1060 nm) were used as laser light sources. In addition, the laser output was appropriately set according to the welding strength and the product burnt condition.

2. Evaluation of Laser Welding Strength The welded state after welding of the laser welded bodies obtained by the above-described method was checked and evaluated according to the following criteria.

(Evaluation criteria)
⊚: Both the welded state and the appearance are good, and the base material is broken in the peeling evaluation, and the welded portion cannot be peeled off.
◯: Good welding state, the welded portion was broken in the evaluation of peeling, but welding traces were observed.
Δ: It is welded, but the welded part is easily peeled off in the peel test, and the weld marks are unclear.
x: No welding.

[Evaluation 2-2]
Appearance of Laser-Welded Product The product appearance of the laser-welded product obtained by the method described in "Evaluation 2-1" above was visually evaluated and evaluated according to the following criteria.

(Evaluation criteria)
⊚: No discoloration is observed, and the surface gloss is excellent.
◯: No discoloration is observed, but the surface gloss is poor.
Δ: Discoloration is observed in part of the product, and the surface gloss is poor.
x: Many discolorations are observed on the product, and the surface gloss is poor.

[Evaluation 2-3]
(Plasticization time)
For each polyamide composition, using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., trade name "NEX50III-5EG"), the cylinder temperature was set to the melting point (Tm2) of the polyamide composition + 20 ° C., and the mold temperature was set. 100 shots were molded under injection molding conditions of 80° C., injection time of 15 seconds, and cooling time of 10 seconds to obtain an ISO test piece in accordance with ISO3167. The average plasticizing time of 100 shots was calculated.

[Evaluation 2-4]
(Release time)
For each polyamide composition, using an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., trade name "NEX50III-5EG"), injection time 10 seconds, screw rotation speed 200 rpm, mold temperature 80 ° C., cylinder temperature polyamide The melting point (Tm2) of the composition is set to +20°C, and the injection pressure and injection speed are adjusted appropriately in a mode in which the filling time is in the range of 0.8 ± 0.1 seconds. 3 mm thick) were manufactured. At that time, the shortest cooling time during which the molded piece automatically dropped from the mold continuously for 10 shots was taken as the release time.

[Evaluation 2-5]
(Flexural modulus under atmospheric equilibrium moisture absorption (flexural modulus (wet)))
For each polyamide composition, an injection molding machine (manufactured by Nissei Plastic Industry Co., Ltd., trade name "NEX50III-5EG") was used to prepare an ISO dumbbell with a thickness of 4 mm in accordance with ISO 3167 and used as a test piece. The obtained test piece was allowed to stand in an atmosphere of constant temperature and humidity (23° C., 50 RH %) to reach water absorption equilibrium, and then the flexural modulus was measured according to ISO178.

[Evaluation 2-6]
(Flame retardance)
The measurement was performed using the method of UL94 (the standard established by Under Writers Laboratories Inc., USA). The test piece (length 127 mm, width 12.7 mm, thickness 0.7 mm) was prepared by attaching a mold for the UL test piece (mold temperature = 100°C) to an injection molding machine (PS40E manufactured by Nissei Kogyo Co., Ltd.). and a cylinder temperature of 290° C., by molding each polyamide composition. The injection pressure was the full filling pressure + 2% pressure when molding the UL test piece. The flame retardant grade was evaluated according to the UL94 standard (vertical burning test) to determine which grade was V-0, V-1, or V-2. In addition, the smaller the numerical value of the grade, the higher the flame retardancy.

<Production of Polyamide Composition>
[Examples 2-1 to 2-10 and Comparative Examples 2-1, 2-3 to 2-5]
(A) crystalline polyamide, (B) amorphous polyamide, (C) laser light transmitting colorant, (D) inorganic filler, (E) phosphorus-based flame retardant, and (F) other components are shown in the tables below. A polyamide composition was prepared as follows using the types and proportions described in .

The raw material polyamide ((A) crystalline polyamide and (B) amorphous polyamide) was dried in a nitrogen stream to adjust the moisture content to about 0.2% by mass, and then used as a raw material for the polyamide composition. board.

The polyamide composition production equipment includes a twin-screw extruder (manufactured by Toshiba Machine Co., Ltd., product name "TEM-58SX" (L / D = 53.8)) and a single-screw extruder (manufactured by Tanabe Plastics Machinery, product The name "S65", (L/D=36)) was used.

In the twin-screw extruder, the temperature from the upstream supply port to the die was set to the melting point Tm2 + 20 ° C. of each (A) crystalline polyamide produced in the above production example, the screw rotation speed was 350 rpm, and the discharge rate was 400 kg / h (Q /N=1.14). In the single-screw extruder, the temperature from the upstream supply port to the die was set to the melting point Tm2 of (A) the crystalline polyamide +20°C, the screw rotation speed was set to 150 rpm, and the discharge rate was set to 50 kg/h.

(A) crystalline polyamide, (B) amorphous polyamide, and (F) other components are dry-blended so that the types and proportions shown in the tables below are obtained, and then the mixture is fed from the upstream side of the twin-screw extruder. supply, (D) inorganic filler and (E) phosphorus-based flame retardant are supplied from the first supply port on the downstream side of the twin-screw extruder, and the melt-kneaded product extruded from the die head is cooled in a strand and pelletized. to obtain pellets of the polyamide composition. The pellets thus obtained and (C) the laser-transmitting colorant are dry-blended, then fed from the upstream feed port of the single-screw extruder, and the melt-kneaded product extruded from the die head is cooled in the form of strands and pelletized. to obtain pellets of the desired polyamide composition (laser ray transmitting polyamide resin composition).
The obtained polyamide composition pellets were dried in a nitrogen stream to reduce the water content in the polyamide composition to 500 ppm or less.

[Comparative Example 2-2]
A polyamide composition was obtained in the same manner as in Comparative Example 2-1, except that a step of annealing the obtained pellets in an oven set at 120° C. for 1 hour was added.

The measurement results and evaluation results of the physical properties of each polyamide composition are shown in the following tables.

From Tables 7 to 12, (A) a crystalline polyamide, (B) an amorphous polyamide, (C) a laser light-transmitting colorant, and (E) containing a phosphorus-based flame retardant, (B) an amorphous polyamide is 10.0% by mass or more and 50.0% by mass or less with respect to the total amount of polyamide in the polyamide composition, and (B) the amorphous polyamide is (A) in the crystalline polyamide With the polyamide compositions (Examples 2-1 to 2-10) that are dispersed in and form domains, laser-welded bodies with excellent welding strength and product appearance can be obtained, and from the viewpoint of plasticization time and mold release time Moldability was good, and the flexural modulus of moisture absorption at atmospheric equilibrium when formed into a molded product was higher than 7.0 GPa, UL94 V-0, and flame retardancy was also good.

In addition, the polyamide compositions (Examples 2-1 to 2-9) having a wavelength dependency (T%(λ)) of laser light of 0.900 or more showed particularly good laser welding strength at wavelengths of 940 nm and 1060 nm. It was found to be compatible with various types of laser light sources.

On the other hand, the polyamide compositions (B) containing no amorphous polyamide (Comparative Examples 2-1 and 2-2) were inferior in product appearance when made into laser-welded bodies. In addition, the polyamide composition (Comparative Example 2-1) had a long plasticizing time of 12.3 seconds, was inferior in moldability, and was also inferior in flexural modulus under atmospheric equilibrium moisture absorption. In addition, it was UL94 V-1 to V-2 and was inferior in flame retardancy.

(B) In the polyamide composition (Comparative Example 2-3) in which the content of the amorphous polyamide is more than 50.0% by mass with respect to the mass of the total polyamide in the polyamide composition, the release time is 30.0%. The result was as long as 0 second and poor in formability. In addition, the laser-welded body was found to be burnt, and the appearance of the product was poor. Moreover, it was UL94 V-2 and inferior in flame retardancy.

The polyamide composition (Comparative Example 2-4) using a crystalline polyamide having a melting point of more than 290° C. was inferior in welding strength and product appearance when made into a laser-welded body. In addition, the plasticizing time was 15.8 seconds and the mold releasing time was long, 25.0 seconds, resulting in poor moldability. Moreover, it was UL94 V-2 and inferior in flame retardancy.

(B) The polyamide composition containing no amorphous polyamide (Comparative Example 2-5) is inferior in welding strength and product appearance when formed into a laser-welded body, and furthermore, compared to the laser welding strength at a wavelength of 1060 nm, As a result, the laser welding strength at a wavelength of 940 nm was inferior, and the types of laser beams used in laser welding were limited. In addition, the plasticizing time was as long as 12.8 seconds, the moldability was poor, and the flexural modulus under atmospheric equilibrium moisture absorption was also poor. Moreover, it was UL94 V-2 and inferior in flame retardancy.

According to the polyamide composition of the present embodiment, a polyamide that exhibits good welding strength and appearance when laser-welded, has excellent rigidity under atmospheric equilibrium moisture absorption when formed into a molded product, and has good moldability. A composition can be provided.

Claims (17)

A polyamide composition containing (A) a crystalline polyamide, (B) an amorphous polyamide, and (C) a laser light transmitting colorant,
The melting point (Tm) of the (A) crystalline polyamide measured by a differential scanning calorimeter is 290.0° C. or less,
The content of the (B) amorphous polyamide is 10.0% by mass or more and 50.0% by mass or less with respect to the mass of the total polyamide in the polyamide composition,
A polyamide composition in which the (B) amorphous polyamide is dispersed in the (A) crystalline polyamide to form domains. A polyamide composition comprising (A) a crystalline polyamide, (B) an amorphous polyamide, (C) a laser light transmitting colorant, and (E) a phosphorus-based flame retardant,
The (A) crystalline polyamide has a melting point (Tm) of 290.0° C. or lower as measured by a differential scanning calorimeter,
The content of the (B) amorphous polyamide is 10.0% by mass or more and 50.0% by mass or less with respect to the mass of the total polyamide in the polyamide composition,
A polyamide composition in which the (B) amorphous polyamide is dispersed in the (A) crystalline polyamide to form domains. The (E) phosphorus-based flame retardant is at least one selected from the group consisting of phosphinates represented by the following general formula (1), diphosphinates represented by the following general formula (2), and condensates thereof 3. The polyamide composition of claim 2, comprising phosphinic acid salts of .

(In general formula (1), R ¹¹ and R ¹² are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. M ⁿ¹¹⁺ is an n11-valent metal ion M is an element belonging to group 2 or 15 of the periodic table, a transition element, zinc or aluminum n11 is 2 or 3. When n11 is 2 or 3, a plurality of ^R11 and Each R ¹² may be the same or different.
In general formula (2), R ²¹ and R ²² are each independently an alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. Y ²¹ is an alkylene group having 1 to 10 carbon atoms or an arylene group having 6 to 10 carbon atoms. M' _x ^m21+ is an m21 valent metal ion. M' is an element belonging to group 2 or group 15 of the periodic table, a transition element, zinc or aluminum. n21 is an integer of 1 or more and 3 or less. When n21 is 2 or 3, multiple R ²¹ , R ²² and Y ²¹ may be the same or different. m21 is 2 or 3; x is 1 or 2; When x is 2, multiple M' may be the same or different. n21, x and m21 are integers satisfying the relational expression 2*n21=m21*x. ) 3. The polyamide composition according to claim 1, wherein the (A) crystalline polyamide is an aliphatic polyamide. 3. The polyamide composition according to claim 1, wherein 50 mol % or more of isophthalic acid units are contained in all dicarboxylic acid units constituting said (B) amorphous polyamide. 6. The polyamide composition according to claim 5, which contains 75 mol % or more of isophthalic acid units in all dicarboxylic acid units constituting the amorphous polyamide (B). 7. The polyamide composition according to claim 6, which contains 100 mol % of isophthalic acid units in all dicarboxylic acid units constituting said (B) amorphous polyamide. 3. The polyamide composition according to claim 1, wherein the (B) amorphous polyamide dispersed in the (A) crystalline polyamide has a number average particle size of domains of 10 nm or more and 1000 nm or less. 3. The polyamide according to claim 1 or 2, wherein the content of the (C) laser light transmitting colorant is 0.01% by mass or more and 5.00% by mass or less with respect to the total mass of the polyamide composition. Composition. A molded article obtained by molding the polyamide composition according to claim 1 . 11. The molded product according to claim 10, wherein the molded product having a thickness of 2.0 mm has a transmittance of 40.0% or more for laser light with a wavelength of 900 nm. The ratio T% _min /T% _max of the minimum value T% min of light transmittance and the maximum value T% _max of light transmittance at a wavelength of 900 _nm or more and 1100 nm or less in the molded article having a thickness of 2.0 mm is 0. 12. The molded article according to claim 10 or 11, which is 750 or more. A molded article obtained by molding the polyamide composition according to claim 2 . 14. The molded article according to claim 13, wherein the molded article having a thickness of 1.0 mm has a transmittance of 35.0% or more for a laser beam having a wavelength of 900 nm. The ratio T% _min /T% max of the minimum value T% min _of light transmittance and the maximum value T% _max of light transmittance at a wavelength of 900 nm or more and 1100 nm or less in the molded article having a thickness _of 1.0 mm is 0. 15. The molded article of claim 13 or 14, which is greater than or equal to .850. A laminate in which a laser light transmitting material and a laser light absorbing material are joined,
The laser light transmitting material is formed by molding the polyamide composition according to claim 1 or 2,
The laser light absorbing material is formed by molding a composition containing a thermoplastic resin and a laser light absorbing colorant,
At least a part of a joint between the laser light transmitting material and the laser light absorbing material is a laser welded part. The difference in softening point between the laser light transmitting material and the laser light absorbing material is ±80.0° C. or less,
17. The laminate according to claim 16, wherein the softening point is the melting point Tm2 measured by a differential scanning calorimeter for crystalline resins, and the glass transition temperature Tg for amorphous resins.