Resin compositions, pellets, and molded articles

Abstract

To provide a resin composition enabling the production of a molded article that excels in various performances, especially flame retardancy, and has a short combustion time when its flame retardancy is evaluated, to provide a pellet and to provide a molded article.SOLUTION: A resin composition contains (A) 45-85 mass% of a semi-aromatic polyamide resin, (B) 10-45 mass% of a reinforcement fiber, (C) 1-10 mass% of a phosphorus-based flame retardant, (D) 0.01-1 mass% of an organic stabilizer, (E) 0.01-1 mass% of a mold release agent, and (F) 0-25.0 mass% of at least one additive other than the above substances, in which the total of the components (A) to (F) is 100.0 mass%, wherein (A) the semi-aromatic polyamide resin contains a diamine unit and a dicarboxylic acid unit, in which more than 50 mol% of the dicarboxylic acid unit has a linear aliphatic chain having 4 to 7 carbon atoms, and (D) the organic stabilizer has a linear or branched alkyl group having 5 or less carbon atoms, and the content of the aliphatic polyamide resin in the resin composition is less than 1 mass%.SELECTED DRAWING: None

Description

[Technical Field]

[0001] This invention relates to resin compositions, pellets, and molded articles. In particular, it relates to resin compositions having polyamide resin as a main component. [Background technology]

[0002] Polyamide resins are used in a wide range of fields due to their excellent mechanical strength. However, the demand for flame retardancy is increasing in applications such as automotive parts, aircraft components, and mobile devices. This is also true for polyamide resins, and there is a need for further improvements in flame retardancy while maintaining mechanical strength.

[0003] Patent Document 1 discloses a flame-retardant resin composition comprising (A) a polyamide resin, (B) a phosphorus-based flame retardant, and (C) glass fibers having a non-circular cross-section, wherein the content of each in the composition is 15 to 78% by weight of (A) the polyamide resin, 2 to 20% by weight of (B) the phosphorus-based flame retardant, and 20 to 65% by weight of (C) the glass fibers having a non-circular cross-section. Furthermore, Patent Document 2 discloses a flame-retardant polyamide resin composition comprising: (a) about 20 to about 90 weight percent of aromatic polyamide derived from about 5 to about 75 mol percent of aromatic monomers; (b) about 10 to about 40 weight percent of a flame retardant comprising a phosphinate of formula (I) and / or a bisphosphinate of formula (II) and / or polymers thereof; (c) an inorganic reinforcing agent and / or a filler of 0 to about 60 weight percent; and (d) at least one synergistic agent of 0 to about 10 weight percent, wherein the percentages described above are based on the total weight of the composition. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Japanese Patent Publication No. 2008-163317 [Patent Document 2] International Publication No. 2005 / 033192 [Overview of the Initiative] [Problems that the invention aims to solve]

[0005] As mentioned above, the addition of phosphorus-based flame retardants to polyamide resins to achieve flame retardancy has been explored in the past. However, in recent years, the demand for flame retardancy has been increasing, and the flame retardancy achieved by adding phosphorus-based flame retardants is no longer sufficient for all applications. In particular, there is a need to shorten the burning time when evaluating the flame retardancy of polyamide resins. On the other hand, even if polyamide resins have high flame retardancy, if the physical properties such as mechanical strength of the molded product are poor, or if the appearance deteriorates, they may not be practical for certain applications. The present invention aims to solve the aforementioned problems and to provide a resin composition, pellets, and molded articles that are excellent in various performance aspects and flame retardancy, and in particular, have a short burning time in flame retardancy evaluation. [Means for solving the problem]

[0006] Based on the above problems, the inventors conducted research and found that by using a semi-aromatic polyamide resin as the polyamide resin, incorporating reinforcing fibers, and combining it with a phosphorus-based flame retardant, along with an organic stabilizer (radical scavenger and / or peroxide decomposer) having 5 or fewer linear or branched alkyl chains, the above problems were solved. Specifically, the above problem was solved by the following means. <1> A resin composition comprising (A) 45-85% by mass of a semi-aromatic polyamide resin, (B) 10-45% by mass of reinforcing fibers, (C) 1-10% by mass of a phosphorus-based flame retardant, (D) 0.01-1% by mass of an organic stabilizer, (E) 0.01-1% by mass of a mold release agent, and (F) 0-25.0% by mass of at least one other additive, wherein the total of components (A) to (F) is 100.0% by mass, wherein the (A) semi-aromatic polyamide resin contains diamine units and dicarboxylic acid units, and more than 50 mol% of the dicarboxylic acid units have linear aliphatic chains having 4 to 7 carbon atoms, and the (D) organic stabilizer has linear or branched alkyl groups having 5 or fewer carbon atoms, and the content of aliphatic polyamide resin in the resin composition is less than 1% by mass. <2> The above (A) includes a polyamide resin in which 70 mol% or more of the diamine units contained in the semi-aromatic polyamide resin are xylylenediamine units, <1> The resin composition described above. <3> The (B) reinforcing fiber includes glass fiber, <1> or <2> The resin composition described above. <4> The (C) phosphorus-based flame retardant comprises at least one of a phosphinate and a diphosphinate. <1> ~ <3> A resin composition as described in any one of the following. <5> The (C) phosphorus-based flame retardant comprises at least one compound represented by formula (I) and one compound represented by formula (II). <1> ~ <3> A resin composition as described in any one of the following. [ka] (In formula (I), R 1 and R 2 Each of these independently represents a linear or branched alkyl group with 1 to 6 carbon atoms, or an aryl group with 6 to 10 carbon atoms. M represents a calcium ion, aluminum ion, magnesium ion, or zinc ion. m is a natural number representing the valency of M. [ka] (In formula (II), R 4 and R 5Each independently represents a linear or branched alkyl group having 1 to 6 carbon atoms or an aryl group having 6 to 10 carbon atoms. R 3 represents a linear or branched alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, an alkylarylene group having 7 to 10 carbon atoms, or an arylalkylene group having 7 to 10 carbon atoms. M represents a calcium ion, an aluminum ion, a magnesium ion, or a zinc ion. n represents a natural number representing the valence of M. n, a, and b are natural numbers that satisfy the relational expression 2 × b = n × a.) <6>The resin composition according to any one of <1> to <5>, wherein the (D) organic stabilizer further has an aromatic ring. <7>The resin composition according to any one of <1> to <5>, wherein the (D) organic stabilizer has a structure represented by formula (d). Formula (d)

Chemical formula

Chemical formula

Chemical formula

Advantages of the Invention

[0007] According to the present invention, it has become possible to provide a resin composition, pellets, and molded articles that are excellent in various performances, excellent in flame retardancy, and particularly have a short combustion time in the evaluation of flame retardancy.

Modes for Carrying Out the Invention

[0008] [[ID=!39]]Hereinafter, modes for carrying out the present invention (hereinafter simply referred to as "the present embodiment") will be described in detail. The following present embodiment is an exemplification for explaining the present invention, and the present invention is not limited only to the present embodiment. It should be noted that there seems to be an issue with the numbering in the original text. For example, "!13" and "!23" and "!25" and "!39" in the translation are just to mark the places where the numbering in the original text seems incorrect. You may want to check and correct the original text numbering for a more accurate translation. In this specification, "~" is used to mean that the numbers before and after it are included as the lower and upper limits, respectively. In this specification, all physical properties and characteristic values ​​shall be those at 23°C unless otherwise specified. In this specification, unless otherwise specified, the number-average molecular weight may be measured in accordance with paragraph 0047 of Japanese Patent Application Publication No. 2018-165298, which is incorporated herein by reference. In this specification, the melting point (Tm) and glass transition temperature (Tg, sometimes referred to as the glass transition point) shall be values ​​measured by differential scanning calorimetry (DSC) in accordance with ISO 11357, unless otherwise specified. Specifically, they may be measured in accordance with paragraph 0036 of International Publication No. 2016 / 084475, which is incorporated herein by reference. If the measurement methods, etc., described in the standards shown herein differ from year to year, unless otherwise specified, the standards as of January 1, 2022 shall apply.

[0009] The resin composition of this embodiment comprises (A) 45 to 85% by mass of a semi-aromatic polyamide resin, (B) 10 to 45% by mass of reinforcing fibers, (C) 1 to 10% by mass of a phosphorus-based flame retardant, (D) 0.01 to 1% by mass of an organic stabilizer, (E) 0.01 to 1% by mass of a mold release agent, and (F) 0 to 25.0% by mass of at least one other additive, wherein the total of components (A) to (F) is 100.0% by mass, characterized in that the (A) semi-aromatic polyamide resin contains diamine units and dicarboxylic acid units, with more than 50 mol% of the dicarboxylic acid units having linear aliphatic chains with 4 to 7 carbon atoms, the (D) organic stabilizer having linear or branched alkyl groups with 5 or fewer carbon atoms, and the aliphatic polyamide resin content in the resin composition is less than 1% by mass. By adopting this configuration, a resin composition can be obtained that maintains high mechanical strength while exhibiting excellent flame retardancy, particularly a short burning time in flame retardancy evaluations, resulting in a molded product. In other words, by using (A) a semi-aromatic polyamide resin containing diamine units and dicarboxylic acid units, where more than 50 mol% of the dicarboxylic acid units are linear aliphatic chains with 4 to 7 carbon atoms (hereinafter sometimes simply referred to as "(A) aromatic polyamide resin") as the polyamide resin, and by using (D) an organic stabilizer having linear or branched alkyl groups with 5 or fewer carbon atoms (hereinafter sometimes simply referred to as "(D) organic stabilizer") together with (C) a phosphorus-based flame retardant, it becomes possible to provide molded products that are excellent in various properties and have excellent flame retardancy, in particular, a short burning time in the evaluation of flame retardancy. This is presumed to be because by using (A) aromatic polyamide resin, the proportion of flammable aliphatic chains is reduced, and the number of carbon atoms in the aliphatic chains is also relatively shortened, making it difficult to burn. Furthermore, although the burning time of polyamide resin is also prolonged by the gases accumulated during heat processing, it is presumed that by using (D) organic stabilizer, the decomposition of the polyamide resin is suppressed and gas generation is reduced. Furthermore, while adding a large amount of low molecular weight components tends to increase the burning time, it is presumed that this was effectively suppressed in this embodiment by precisely adjusting the amount of each component. In addition, adding a large amount of low molecular weight components makes it easier for bleed-out to occur on the surface, which facilitates the formation of tracking circuits, leading to a decrease in CTI (CTI according to the test method specified in the international standard IEC60112) and deterioration of the appearance due to bleed-out. However, it is presumed that this problem was also solved in this embodiment by precisely adjusting the amount of each component. The following describes this embodiment in detail.

[0010] <(A) Semi-aromatic polyamide resin> The resin composition of this embodiment contains (A) a semi-aromatic polyamide resin in a proportion of 45 to 85% by mass, wherein the (A) semi-aromatic polyamide resin contains diamine units and dicarboxylic acid units, and more than 50 mol% of the dicarboxylic acid units have linear aliphatic chains with 4 to 7 carbon atoms. By using such a semi-aromatic polyamide resin, a resin composition with excellent flame retardancy can be obtained. Here, semi-aromatic polyamide resin refers to monomer units constituting the semi-aromatic polyamide resin in which 30 mol% or more of the total monomer units excluding terminal groups are aromatic monomer units, preferably 40 mol% or more are aromatic monomer units, more preferably 45 mol% or more are aromatic monomer units, preferably 70 mol% or less are aromatic monomer units, more preferably 65 mol% or less are aromatic monomer units, even more preferably 60 mol% or less are aromatic monomer units, and even more preferably 55 mol% or less are aromatic monomer units. Aromatic monomers refer to monomers having an aromatic ring, and include aromatic diamines such as xylylenediamine, aromatic dicarboxylic acids such as isophthalic acid and terephthalic acid, and aromatic aminocarboxylic acids.

[0011] The (A) semi-aromatic polyamide resin used in this embodiment contains diamine units and dicarboxylic acid units, with more than 50 mol% of the dicarboxylic acid units having linear aliphatic chains with 4 to 7 carbon atoms. By using dicarboxylic acids with short aliphatic chains in this way, the burning time of the molded article can be shortened. In particular, in this embodiment, it is preferable that the (A) semi-aromatic polyamide resin does not substantially contain monomer units containing linear aliphatic chains with 8 or more carbon atoms. Here, substantially does not contain means that the proportion of monomer units containing linear aliphatic chains with 8 or more carbon atoms among all monomer units constituting the (A) semi-aromatic polyamide resin, excluding terminal groups, is 10% by mass or less, preferably 5% by mass or less, more preferably 3% by mass or less, and even more preferably 1% by mass or less. With such a configuration, it is possible to manufacture molded articles with superior flame retardancy, in particular, with shorter burning times.

[0012] In this embodiment, it is preferable that 70 mol% or more of the diamine units contained in the (A) semi-aromatic polyamide resin are xylylenediamine units. Hereinafter, such (A) semi-aromatic polyamide resin may be referred to as xylylenediamine-based polyamide resin.

[0013] In xylylenediamine-based polyamide resins, it is preferable to use metaxylylenediamine and / or paraxylylenediamine as the xylylenediamine. In this embodiment, it is preferable that the xylylenediamine is either metaxylylenediamine alone or a mixture (copolymer) of metaxylylenediamine and paraxylylenediamine. In xylylenediamine, the molar ratio of metaxylylenediamine to paraxylylenediamine is preferably 100:0 to 10:90, more preferably 100:0 to 15:85, even more preferably 100:0 to 50:50, even more preferably 100:0 to 60:40, and even more preferably 80:20 to 65:45. In xylylenediamine-based polyamide resins, the diamine units are preferably 75 mol% or more, more preferably 80 mol% or more, even more preferably 90 mol% or more, even more preferably 95 mol% or more, and even more preferably 98 mol% or more.

[0014] Other diamines that can be used as raw material diamine components for xylylenediamine-based polyamide resins include aliphatic diamines such as tetramethylenediamine, pentamethylenediamine, 2-methylpentanediamine, hexamethylenediamine, heptamethylenediamine, octamethylenediamine, nonamethylenediamine, decamethylenediamine, dodecamethylenediamine, 2,2,4-trimethylhexamethylenediamine, and 2,4,4-trimethylhexamethylenediamine, as well as 1,3-bis(aminomethyl) Examples include alicyclic diamines such as chlorohexane, 1,4-bis(aminomethyl)cyclohexane, 1,3-diaminocyclohexane, 1,4-diaminocyclohexane, bis(4-aminocyclohexyl)methane, 2,2-bis(4-aminocyclohexyl)propane, bis(aminomethyl)decalin, and bis(aminomethyl)tricyclodecane, as well as aromatic ring-containing diamines such as bis(4-aminophenyl) ether, paraphenylenediamine, and bis(aminomethyl)naphthalene. These can be used individually or in combination of two or more.

[0015] In xylylenediamine-based polyamide resins, it is preferable that the dicarboxylic acid units are preferably 70 mol% or more, more preferably 80 mol% or more, even more preferably 90 mol% or more, even more preferably 95 mol% or more, and even more preferably 98 mol% or more, and are dicarboxylic acid units having a linear aliphatic chain with 4 to 7 carbon atoms, and more preferably adipic acid units.

[0016] In addition, examples of dicarboxylic acids other than those mentioned above include phthalate compounds such as isophthalic acid, terephthalic acid, and orthophthalic acid, and naphthalenedicarboxylic acids such as 1,2-naphthalenedicarboxylic acid, 1,3-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,5-naphthalenedicarboxylic acid, 1,6-naphthalenedicarboxylic acid, 1,7-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, and 2,7-naphthalenedicarboxylic acid, and can be used individually or in combination of two or more.

[0017] The (A) semi-aromatic polyamide resin used in this embodiment mainly consists of diamine units and dicarboxylic acid units, but this does not exclude the inclusion of other monomer units. It goes without saying that it may also contain lactams such as ε-caprolactam and laurolactam, and aliphatic aminocarboxylic acid units such as aminocaproic acid and aminoundecanoic acid. Here, "main components" means that among the monomer units constituting the semi-aromatic polyamide resin, the total number of diamine units and dicarboxylic acid units is the largest among all monomer units. In this embodiment, the total of diamine units and dicarboxylic acid units in the semi-aromatic polyamide resin preferably accounts for 90.0% by mass or more of the total monomer units, and more preferably 95.0% by mass or more.

[0018] The melting point of the semi-aromatic polyamide resin used in the resin composition of this embodiment is preferably 200°C or higher, and preferably 300°C or lower. Using such a semi-aromatic polyamide resin tends to more effectively improve mechanical strength and flame retardancy.

[0019] The (A) semi-aromatic polyamide resin used in the resin composition of this embodiment preferably has a lower limit of number average molecular weight (Mn) of 6,000 or more, more preferably 8,000 or more, even more preferably 10,000 or more, even more preferably 15,000 or more, and even more preferably 20,000 or more. The upper limit of Mn is preferably 35,000 or less, more preferably 30,000 or less, and even more preferably 28,000 or less.

[0020] The resin composition of this embodiment is a resin composition in which the sum of (A) to (E) above is 100.0% by mass, and contains (A) semi-aromatic polyamide resin in a proportion of 48 to 85% by mass. By setting it above the lower limit, flame retardancy tends to improve while maintaining mechanical properties. The content of (A) semi-aromatic polyamide resin in the resin composition of this embodiment is preferably 50% by mass or more, preferably 80% by mass or less, more preferably 70% by mass or less, and even more preferably 65% ​​by mass or less. The resin composition of this embodiment may contain only one type of (A) semi-aromatic polyamide resin, or it may contain two or more types. If it contains two or more types, it is preferable that the total amount is within the above range.

[0021] The resin composition of this embodiment also preferably contains less than 1% by mass of aliphatic polyamide resin, and more preferably 0.5% by mass or less. By reducing the content of aliphatic polyamide resin in the resin composition in this way, the burning time when the resin composition burns can be shortened. The content of aliphatic polyamide resin in the resin composition of this embodiment is also preferably less than 1% by mass of the content of (A) semi-aromatic polyamide resin in the resin composition, more preferably 0.5% by mass or less, and even more preferably 0.1% by mass or less. In this embodiment, the aliphatic polyamide resin refers to a polyamide resin in which more than 70 mol% of the monomer units constituting the polyamide resin are aliphatic monomer units. Aliphatic monomers refer to monomers other than aromatic monomers, and include lactams, aliphatic diamines, aliphatic dicarboxylic acids, aliphatic aminocarboxylic acids, etc. Specific examples of aliphatic polyamide resins include polyamide 6, polyamide 66, polyamide 11, and polyamide 12.

[0022] (B) Reinforced Fiber The resin composition of this embodiment contains (B) reinforcing fibers in a proportion of 10 to 45% by mass. By including (B) reinforcing fibers, a molded product with excellent mechanical strength can be obtained. (B) The reinforcing fibers may be organic or inorganic, with inorganic fibers being preferred. (B) The reinforcing fibers are preferably plant fibers, carbon fibers, glass fibers, alumina fibers, boron fibers, ceramic fibers, aramid fibers, etc., more preferably selected from carbon fibers and glass fibers, and even more preferably glass fibers.

[0023] As glass fibers, commonly supplied materials such as E glass, C glass, A glass, S glass, D glass, R glass, and alkali-resistant glass are used, but any material that can be made into glass fibers can be used, and is not particularly limited. In this invention, it is preferable to include E glass.

[0024] Preferably, the glass fibers are surface-treated with a surface treatment agent such as a silane coupling agent, such as γ-methacrylateoxypropyltrimethoxysilane, γ-glycidoxypropyltrimethoxysilane, or γ-aminopropyltriethoxysilane. The amount of surface treatment agent applied is preferably 0.01 to 1.0% by mass of the glass fibers. Furthermore, if necessary, glass fibers may be surface-treated with a lubricant such as a fatty acid amide compound or silicone oil, an antistatic agent such as a quaternary ammonium salt, a resin with film-forming ability such as epoxy resin or urethane resin, or a mixture of a resin with film-forming ability and a heat stabilizer or flame retardant.

[0025] The glass fibers used in the resin composition of this embodiment are commercially available. Examples of commercially available products include T275H, T286H, T756H, T289, T289DE, T289H, and T296GH from Nippon Electric Glass (NEG); DEFT2A from Owens Corning; HP3540 from PPG; CSG3PA-810S and CSG3PA-820 from Nitto Boseki Co., Ltd.; EFH50-31 from Central Glass Fiber Co., Ltd.; and CS301HP from Chongqing Polycomp International (all are trade names).

[0026] (B) The cross-section of the reinforcing fiber may be circular or non-circular (elliptical, oblong, rectangular, a rectangle with semicircles on both short sides, cocoon-shaped, etc.), but a circular cross-section is preferred. In the present invention, when a reinforcing fiber having a circular cross-section is used, the effect of improving flame retardancy and mechanical strength is particularly remarkable. The term "circular" here includes not only a perfect circle in a geometric sense, but also what is commonly referred to as a circle in the technical field of this invention. Examples of non-circular cross-section reinforcing fibers include the flattened reinforcing fibers described in paragraphs 0048 to 0052 of Japanese Patent Publication No. 2012-214819, the details of which are incorporated herein by reference.

[0027] The (B) reinforcing fibers in the resin composition of this embodiment preferably have a number average fiber length of 100 μm or more, more preferably 150 μm or more, and even more preferably 200 μm or more. The upper limit is preferably 10 mm or less, more preferably 8 mm or less, and even more preferably 5 mm or less.

[0028] The (B) reinforcing fibers used in the resin composition of this embodiment preferably have a number average fiber diameter of 1 μm or more, more preferably 2 μm or more, and even more preferably 5 μm or more. The upper limit is preferably 50 μm or less, more preferably 30 μm or less, and even more preferably 20 μm or less. In this embodiment, (B) the reinforcing fiber is preferably chopped strand.

[0029] The proportion of (B) reinforcing fibers (preferably glass fibers) in the resin composition of this embodiment has a lower limit of 10% by mass or more, preferably 15% by mass or more, more preferably 20% by mass or more, even more preferably 25% by mass or more, and may be 30% by mass or more. The upper limit of the content of (B) reinforcing fibers (preferably glass fibers) is 45% by mass or less, preferably 40% by mass or less, and more preferably 38% by mass or less. Setting the amount above the lower limit can improve mechanical strength and flame retardancy. On the other hand, setting the amount of (B) reinforcing fibers below the upper limit tends to improve the appearance of the resulting molded product. The resin composition of this embodiment may contain only one type of (B) reinforcing fiber, or two or more types. When two or more types are included, it is preferable that the total amount is within the above range.

[0030] <(C) Phosphorus-based flame retardant> The resin composition of this embodiment contains (C) a phosphorus-based flame retardant in a proportion of 1 to 10% by mass. By including (C) a phosphorus-based flame retardant, flame retardancy can be achieved in the resulting molded article. (C) Examples of phosphorus-based flame retardants include phosphorus, phosphates, phosphate esters, phosphazenes, and reaction products of melamine and phosphoric acid. For the reaction products of melamine and phosphoric acid, refer to paragraph 0028 of Japanese Patent Application Publication No. 2018-065974, which is incorporated herein by reference. In this embodiment, it is preferable that (C) the phosphorus-based flame retardant includes at least one of a phosphinate and a diphosphinate.

[0031] In this embodiment, it is preferable that the (C) phosphorus-based flame retardant further includes at least one compound represented by formula (I) and a compound represented by formula (II). [ka] (In formula (I), R 1 and R 2 Each of these independently represents a linear or branched alkyl group with 1 to 6 carbon atoms, or an aryl group with 6 to 10 carbon atoms. M represents a calcium ion, aluminum ion, magnesium ion, or zinc ion. m is a natural number representing the valency of M. [ka] (In formula (II), R 4 and R 5 Each of these independently represents a linear or branched alkyl group with 1 to 6 carbon atoms, or an aryl group with 6 to 10 carbon atoms. 3 represents a linear or branched alkylene group with 1 to 10 carbon atoms, an arylene group with 6 to 10 carbon atoms, an alkylarylene group with 7 to 10 carbon atoms, or an arylalkylene group with 7 to 10 carbon atoms. M represents a calcium ion, aluminum ion, magnesium ion, or zinc ion. n is a natural number representing the valence of M. n, a, and b are natural numbers satisfying the relationship 2 × b = n × a.

[0032] In equation (I), R 1 and R 2Each of these independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms, preferably a methyl group, an ethyl group, a propyl group, or a phenyl group. M represents a calcium ion, an aluminum ion, a magnesium ion, or a zinc ion. m is a natural number representing the valency of M, preferably 2 or 3.

[0033] In equation (II), R 4 and R 5 Each of these independently represents a linear or branched alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms, preferably a methyl group, an ethyl group, a propyl group, or a phenyl group. 3 represents a linear or branched alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, an alkylarylene group having 7 to 10 carbon atoms, or an arylalkylene group having 7 to 10 carbon atoms, preferably a methylene group, an ethylene group, a propylene group, or a phenylene group. M represents a calcium ion, an aluminum ion, a magnesium ion, or a zinc ion. n is a natural number representing the valence of M. n, a, and b are natural numbers that satisfy the relationship 2 × b = n × a. n is preferably 2 or 3. b is preferably 1, 2, or 3, and more preferably 1 or 3. a is preferably 1 or 2.

[0034] Phosphinates or diphosphinates specifically include those produced in an aqueous medium using phosphinic acid and metal carbonates, metal hydroxides, or metal oxides. Phosphinates or diphosphinates are basically monomeric compounds, but depending on the reaction conditions, they may also become polymeric phosphinates with a degree of condensation of 1 to 3 under certain environmental conditions.

[0035] Examples of phosphinic acids or diphosphinic acids include dimethylphosphinic acid, ethylmethylphosphinic acid, diethylphosphinic acid, methyl-n-propylphosphinic acid, methanedi(methylphosphinic acid), benzene-1,4-di(methylphosphinic acid), methylphenylphosphinic acid, and diphenylphosphinic acid.

[0036] Examples of phosphinates include calcium dimethylphosphinate, magnesium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium ethylmethylphosphinate, magnesium ethylmethylphosphinate, aluminum ethylmethylphosphinate, zinc ethylmethylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum diethylphosphinate, zinc diethylphosphinate, calcium methyl-n-propylphosphinate, magnesium methyl-n-propylphosphinate, aluminum methyl-n-propylphosphinate, zinc methyl-n-propylphosphinate, calcium methylphenylphosphinate, magnesium methylphenylphosphinate, aluminum methylphenylphosphinate, zinc methylphenylphosphinate, calcium diphenylphosphinate, magnesium diphenylphosphinate, aluminum diphenylphosphinate, and zinc diphenylphosphinate.

[0037] Examples of diphosphinates include calcium methanedi(methylphosphinate), magnesium methanedi(methylphosphinate), aluminum methanedi(methylphosphinate), zinc methanedi(methylphosphinate), calcium benzene-1,4-di(methylphosphinate), magnesium benzene-1,4-di(methylphosphinate), aluminum benzene-1,4-di(methylphosphinate), and zinc benzene-1,4-di(methylphosphinate).

[0038] Among these phosphinates or diphosphinates, aluminum ethylmethylphosphinate, aluminum diethylphosphinate, and zinc diethylphosphinate are particularly preferred from the viewpoint of flame retardancy and electrical properties. Specific examples of such products include Clariant's EXOLIT OP 1230 (phosphinate metal salt) and EXOLIT OP 1400 (both trade names).

[0039] The content of (C) phosphorus-based flame retardant (preferably at least one of phosphinate and diphosphinate) in the resin composition of this embodiment is 1% by mass or more, preferably 2% by mass or more, more preferably 2.5% by mass or more, even more preferably 3% by mass or more, and even more preferably 5% by mass or more. The upper limit of the content of (C) phosphorus-based flame retardant (preferably at least one of phosphinate and diphosphinate) in the resin composition is 10% by mass or less, preferably 9% by mass or less, and even more preferably 8% by mass or less. If the amount of (C) phosphorus-based flame retardant is too high, the resulting molded article will have excellent flame retardancy, but its mechanical strength will be poor, and it will be prone to causing gas and mold contamination during molding. The resin composition of this embodiment may contain only one type of (C) phosphorus-based flame retardant, or it may contain two or more types. When two or more types are included, it is preferable that the total amount is within the above range.

[0040] <(D) Organic stabilizers> The resin composition of this embodiment contains (D) an organic stabilizer in a proportion of 0.01 to 1% by mass, wherein the (D) organic stabilizer has a linear or branched alkyl group with 5 or fewer carbon atoms. By including the (D) organic stabilizer together with the (C) phosphorus-based flame retardant, the burning time of the molded article can be shortened. (D) The linear or branched alkyl group having 5 or fewer carbon atoms in the organic stabilizer is preferably a methyl group, an ethyl group, an isopropyl group, or a t-butyl group, and more preferably a t-butyl group. In this embodiment, the number of linear or branched alkyl groups having 5 or fewer carbon atoms in the organic stabilizer (D) is preferably 1 to 3 per molecule. (D) The organic stabilizer also preferably has an aromatic ring, and more preferably has a benzene ring. (D) The organic stabilizer preferably has the structure represented by formula (d). Formula (d) [ka] (In formula (d), R is a linear or branched alkyl group having 5 or fewer carbon atoms, or a hydroxyl group, and x is an integer from 0 to 3. * indicates the bond position with other sites.) R is preferably a hydroxyl group or a linear or branched alkyl group having 5 or fewer carbon atoms, and is preferably a methyl group, ethyl group, isopropyl group, or t-butyl group. In formula (d), it is preferable that at least one of R is a t-butyl group. x is preferably 1 or 2.

[0041] (D) The molecular weight of the organic stabilizer is preferably 400 or more, more preferably 500 or more, even more preferably 550 or more, even more preferably 600 or more, and preferably 1500 or less, and more preferably 1200 or less. Such (D) organic stabilizers are preferably phosphorus-containing compounds and / or hindered phenol compounds, and more preferably hindered phenol compounds.

[0042] (D) Examples of commercially available organic stabilizers include Irgafos 168 from BASF, and Adeka Stab AO-20, Adeka Stab AO-30, Adeka Stab AO-40, Adeka Stab AO-50, Adeka Stab AO-50F, Adeka Stab AO-50T, Adeka Stab AO-80, Adeka Stab AO-330 from ADEKA.

[0043] The content of (D) organic stabilizer in the resin composition of this embodiment is 0.01% by mass or more, preferably 0.05% by mass or more, more preferably 0.08% by mass or more, even more preferably 0.1% by mass or more, even more preferably 0.15% by mass or more, and even more preferably 0.2% by mass or more. Setting it above the lower limit tends to shorten the burning time. Furthermore, the content of (D) organic stabilizer in the resin composition is 1% by mass or less, preferably 0.8% by mass or less, more preferably 0.7% by mass or less, even more preferably 0.6% by mass or less, even more preferably 0.5% by mass or less, and even more preferably 0.4% by mass or less. Setting it below the upper limit tends to shorten the burning time. The resin composition of this embodiment may contain only one type of (D) organic stabilizer, or it may contain two or more types. If it contains two or more types, it is preferable that the total amount is within the above range.

[0044] <(E) Release agent> The resin composition of this embodiment contains (E) a release agent in a proportion of (E) 0.01 to 1% by mass. (E) Release agents are mainly used to improve productivity during the molding of resin compositions. (E) Examples of release agents include aliphatic carboxylic acid amides, aliphatic carboxylic acids, esters of aliphatic carboxylic acids and alcohols, aliphatic hydrocarbon compounds with a number average molecular weight of 200 to 15000, polysiloxane-based silicone oils, and higher fatty acid metal salts, with higher fatty acid metal salts being preferred. In particular, in the resin composition of this embodiment, the amount of reinforcing fibers can be about 10 to 40% by mass of the resin composition, so higher fatty acid metal salts, which are generally strongly alkaline release agents, can also be preferably used. The higher fatty acids constituting the higher fatty acid metal salt are preferably fatty acids having 8 or more carbon atoms, and more preferably fatty acids having 8 to 40 carbon atoms. The fatty acids are preferably monocarboxylic acids. Examples of higher fatty acids include saturated fatty acids such as octic acid, lauric acid, myristic acid, palmitic acid, stearic acid, 12-hydroxystearic acid, behenic acid, montanic acid, and sebacic acid, as well as unsaturated fatty acids such as erucic acid, oleic acid, and ricinoleic acid. Preferably, montanic acid, 12-hydroxystearic acid, and behenic acid are used, and more preferably montanic acid. The higher fatty acid metal salts that can be used in this embodiment are metal salts of the above-mentioned higher fatty acids. Examples of metal elements that form metal salts include Group 1 elements (alkali metals) such as sodium and potassium; Group 2 elements (alkaline earth metals) such as calcium, magnesium, and barium; and Group 3 elements such as zinc and aluminum. Preferably, the salts are calcium salts, magnesium salts, zinc salts, and aluminum salts, and more preferably calcium salts. Examples of higher fatty acid metal salts include calcium 12-hydroxystearate, zinc 12-hydroxystearate, magnesium 12-hydroxystearate, aluminum 12-hydroxystearate, calcium behenate, zinc behenate, magnesium behenate, calcium montana, zinc montana, magnesium montana, and aluminum montana, with calcium montana being preferred.

[0045] For further details regarding the release agent, please refer to paragraphs 0037-0042 of Japanese Patent Publication No. 2016-196563, paragraphs 0067-0070 of Japanese Patent Publication No. 2021-161125, and paragraphs 0048-0058 of Japanese Patent Publication No. 2016-078318, in addition to the above, and these contents are incorporated herein by reference.

[0046] (E) The content of the release agent (preferably a higher fatty acid metal salt) is 0.01% by mass or more, more preferably 0.1% by mass or more, with an upper limit of 1% by mass or less, preferably 0.8% by mass or less, and even more preferably 0.5% by mass or less, based on 100% by mass of the resin composition. By setting the content within this range, good release properties can be achieved when performing mold molding such as injection molding, and mold contamination can be effectively suppressed. (E) The release agent may be used alone or in combination of two or more types. When using two or more types, it is preferable that the total amount be within the above range.

[0047] <(F) Other additives> The resin composition of this embodiment may contain at least one additive (F) other than (A) to (E) in a proportion of 0 to 25.0% by mass. That is, the resin composition of this embodiment may consist only of the components (A) to (E) above, or it may contain the above plus (F) other additives in a proportion of 25.0% by mass or less.

[0048] (F) Examples of other additives include nucleating agents, alkalis, elastomers, titanium dioxide, hydrolysis resistance modifiers, matting agents, plasticizers, dispersants, antistatic agents, color inhibitors, gelling inhibitors, and colorants. Details of these can be found in paragraphs 0130 to 0155 of Japanese Patent No. 4894982, which are incorporated herein by reference. (F) The total amount of other additives is preferably 20.0% by mass or less of the resin composition, more preferably 15.0% by mass or less, even more preferably 10.0% by mass or less, and even more preferably 5.0% by mass or less. The lower limit of the content of (F) other additives is preferably 0.1% by mass or more. (F) Other additives may be used alone or in combination of two or more.

[0049] <<Nuclear agent>> As described above, the resin composition of this embodiment may contain a nucleating agent. Including a nucleating agent can improve the appearance. Talc is preferred as the nucleating agent. The talc may be surface-treated with at least one compound selected from polyorganohydrogensiloxanes and organopolysiloxanes. In this case, the amount of siloxane compound attached to the talc is preferably 0.1 to 5% by mass of the talc.

[0050] The content of the nucleating agent in the resin composition of this embodiment is preferably 0.1 to 15 parts by mass, more preferably 0.1 to 10 parts by mass, and even more preferably 0.1 to 5 parts by mass, per 100 parts by mass of the aromatic polyamide resin (A).

[0051] <<Coloring agent>> The resin composition of this embodiment may contain a coloring agent, particularly a black coloring agent. While there are no specific requirements for the type of black coloring agent, examples include pigments such as carbon black and titanium black, as well as nigrosine and aniline black, with carbon black being preferred.

[0052] Any conventionally known carbon black can be used as the carbon black in this embodiment. Examples include furnace black, channel black, Ketjen black, and acetylene black. Among these, those with excellent opacity and a DBP absorption of 30-300 g / 100 cm² are particularly suitable. 3 Using carbon black, especially furnace black, is preferable because it allows for the development of a stable color tone.

[0053] The content of the coloring agent (preferably a black coloring agent) in the resin composition of this embodiment is preferably 0.1 parts by mass or more, preferably 10 parts by mass or less, more preferably 5 parts by mass or less, and even more preferably 4 parts by mass or less, per 100 parts by mass of the semi-aromatic polyamide resin (A). By keeping the content below the above upper limit, higher mechanical properties tend to be obtained. The resin composition of this embodiment may contain only one coloring agent or two or more. When two or more coloring agents are included, it is preferable that the total amount is within the above range.

[0054] <Properties of resin compositions> The resin composition of this embodiment preferably has a bending strength of 290 MPa or more, more preferably 301 MPa or more, and even more preferably 316 MPa or more, at a temperature of 23°C when molded into an ISO tensile test specimen (4 mm thick) in accordance with ISO 178. There is no upper limit to the bending strength, but 500 MPa or less is practical.

[0055] The resin composition of this embodiment preferably has a flexural modulus of 10.0 GPa or higher, more preferably 12.0 GPa or higher, and even more preferably 14.0 GPa or higher, at a temperature of 23°C when molded into an ISO tensile test specimen (4 mm thick) in accordance with ISO 178. There is no particular upper limit for the flexural modulus, but 30 GPa or less is practical.

[0056] The resin composition of this embodiment, when molded into an ISO tensile test specimen (4 mm thick) in accordance with ISO 179-1 and 2, exhibits a notched Charpy impact strength of 6 kJ / m² under conditions of 23°C and 50% humidity. 2 Preferably, it is 7 kJ / m 2 It is preferable that the value be greater than or equal to the above. There is no specific upper limit, but it is 20 kJ / m³. 2 The following is practical.

[0057] The resin composition of this embodiment is preferably molded to a thickness of 1.5 mm and subjected to a UL94 combustion test, resulting in a V-0 rating. Furthermore, the resin composition of this embodiment is preferably molded to a thickness of 0.5 mm and subjected to a UL94 combustion test, resulting in a V-1 rating or higher, and more preferably a V-0 rating. The resin composition of this embodiment, when molded to a thickness of 1.5 mm and subjected to a UL94 combustion test, preferably has a total burning time of 38 seconds or less, more preferably 35 seconds or less, and even more preferably 29 seconds or less. The lower limit is ideally 0 seconds, but 5 seconds or more is practical. Bending strength, flexural strength, Charpy impact strength, and UL94 combustion test are measured by the method described in the examples below.

[0058] <Method for producing resin compositions> In this embodiment, the method for producing the resin composition is not particularly specified, and a wide range of known methods for producing thermoplastic resin compositions can be used. Specifically, the resin composition can be produced by pre-mixing each component using various mixers such as a tumbler or a Henschel mixer, and then melt-kneading them using a Banbury mixer, rolls, brabender, single-screw extruder, twin-screw extruder, kneader, etc.

[0059] Furthermore, for example, a resin composition can be manufactured by supplying the components to an extruder using a feeder, either without pre-mixing them or by pre-mixing only some of the components, and then melt-kneading them together. Furthermore, for example, a composition obtained by pre-mixing some of the components and supplying it to an extruder for melt-kneading can be used as a masterbatch, and pellets can be produced by mixing this masterbatch with the remaining components again and melt-kneading it.

[0060] <Molded products> The molded article of this embodiment is formed from the resin composition or pellets of this embodiment. The method for manufacturing the molded article of this embodiment is not particularly defined. As an example, an injection-molded article formed by injection molding is provided. For example, the molded article of this embodiment may be formed by melting and kneading each component and then directly using various molding methods, or the components may be melted and kneaded to form pellets, then melted again and molded using various molding methods.

[0061] The method for molding the molded product is not particularly limited, and a conventionally known molding method can be adopted. For example, an injection molding method, an injection compression molding method, an extrusion molding method, a profile extrusion method, a transfer molding method, a hollow molding method, a gas assist hollow molding method, a blow molding method, an extrusion blow molding, an IMC (in-mold coating molding) molding method, a rotational molding method, a multi-layer molding method, a two-color molding method, an insert molding method, a sandwich molding method, a foam molding method, a compression molding method, etc. can be used.

[0062] The shape of the molded product of the present embodiment is not particularly limited and can be appropriately selected according to the use and purpose of the molded product. For example, plate-like, plate-shaped, rod-shaped, sheet-shaped, film-shaped, cylindrical, annular, circular, elliptical, gear-shaped, polygonal-shaped, irregular-shaped products, hollow products, frame-shaped, box-shaped, panel-shaped ones, etc. can be mentioned.

[0063] The application field of the molded product of the present embodiment is not particularly defined and is widely used in transportation machine parts such as automobiles, general machine parts, precision machine parts, electronic and electrical equipment parts, OA equipment parts, building materials and housing-related parts, medical devices, leisure sports goods, toys, medical products, daily necessities such as food packaging films, defense and aerospace products, etc.

Examples

[0064] The present invention will be described more specifically with reference to the following examples. The materials, amounts used, ratios, treatment contents, treatment procedures, etc. shown in the following examples can be appropriately changed without departing from the spirit of the present invention. Therefore, the scope of the present invention is not limited to the specific examples shown below. When the measuring instruments, etc. used in the examples are difficult to obtain due to being obsolete, etc., measurement can be performed using other devices having equivalent performance.

[0065] 1. Raw materials <Polyamide resin> PAMP6: Synthesized according to the following synthesis example. <<Synthesis example of PAMP6>> Into a reaction vessel equipped with a stirrer, a partial condenser, a cooler, a thermometer, a dropping device, a nitrogen inlet tube, and a strand die, 7220 g (49.4 mol) of adipic acid (manufactured by Roadia) and 11.66 g of sodium acetate / sodium hypophosphite monohydrate (molar ratio = 1 / 1.5) were charged. After sufficient nitrogen substitution, the system was heated to melt at 170 °C while squeezing the inside of the system under a small amount of nitrogen flow. 6647 g (34.16 mol of metaxylylenediamine, 14.64 mol of pxylylenediamine, manufactured by Mitsubishi Gas Chemical Co., Ltd.) of a mixed xylylenediamine in which the molar ratio of metaxylylenediamine to pxylylenediamine is 70 / 30 was dropped into the melt in the reaction vessel with stirring. While discharging the generated condensed water out of the system, the internal temperature was continuously raised to 260 °C over 2.5 hours. After the dropping was completed, the internal temperature was raised. When it reached 270 °C, the inside of the reaction vessel was depressurized, and the internal temperature was further raised to continue the melt polycondensation reaction at 280 °C for 20 minutes. Then, the system was pressurized with nitrogen, and the obtained polymer was taken out from the strand die and pelletized to obtain a polyamide resin. When the melting point was measured according to the method described below, it was 256 °C.

[0066] PAMXD6: Manufactured by Mitsubishi Gas Chemical Co., Ltd., #6000, polyamide resin synthesized from metaxylylenediamine and adipic acid, melting point 237 °C, glass transition temperature 85 °C PA66: Polyamide 66, manufactured by Invista, U4800, melting point 264 °C

[0067] PAPXD10: Synthesized according to the following synthesis example. <<Synthesis example of PAPXD10>> In a 50-liter reaction vessel equipped with a stirrer, condenser, condenser, thermometer, dropper, nitrogen inlet tube, and strand die, 8950 g (44.25 mol) of accurately weighed sebacic acid (manufactured by Ito Oil Co., Ltd., product name Sebaciic Acid TA), 12.54 g (0.074 mol) of calcium hypophosphite, and 6.45 g (0.079 mol) of sodium acetate were weighed and charged. After thoroughly purging the reaction vessel with nitrogen, the vessel was pressurized to 0.4 MPa with nitrogen, and the temperature was raised from 20°C to 190°C while stirring, allowing the sebacic acid to dissolve uniformly over 55 minutes. Next, 5960 g (43.76 mol) of paraxylylenediamine (manufactured by Mitsubishi Gas Chemical Co., Ltd.) was added dropwise over 110 minutes while stirring. During this time, the temperature inside the reaction vessel was continuously raised to 293°C. During the dropwise addition step, the pressure was controlled to 0.42 MPa, and the generated water was removed from the system through a partial condenser and condenser. The temperature of the partial condenser was controlled within the range of 145-147°C. After the dropwise addition of paraxylylenediamine was complete, the polycondensation reaction was continued for 20 minutes at a reaction vessel pressure of 0.42 MPa. During this time, the temperature inside the reaction vessel was raised to 296°C. Subsequently, the pressure inside the reaction vessel was reduced from 0.42 MPa to 0.12 MPa over 30 minutes. During this time, the temperature inside the vessel was raised to 298°C. Then, the pressure was reduced at a rate of 0.002 MPa / min to 0.08 MPa over 20 minutes to adjust the amount of components with a molecular weight of 1,000 or less. The temperature inside the reaction vessel at the completion of the reduced pressure was 301°C. Subsequently, the system was pressurized with nitrogen, and at a reaction vessel temperature of 301°C and resin temperature of 301°C, the polymer was extracted from the strand die in strand form and cooled in 20°C cooling water. This was then pelletized to obtain approximately 13 kg of polyamide resin. The cooling time in the cooling water was 5 seconds, and the strand withdrawal rate was 100 m / min. Hereinafter referred to as "PAPXD10".

[0068] <Glass fiber (GF)> ECS301HP: Manufactured by Chongqing Polycomp International, a chopped glass fiber with a circular cross-section, fiber diameter of 10 μm, E-glass.

[0069] <Release agent> CS8CP: Calcium montane, manufactured by Nitto Chemical Industries, Ltd. Light Amide WH-255: Manufactured by Kyoeisha Chemical Co., Ltd., a higher fatty acid amide

[0070] <Colorant> #45: Carbon black, manufactured by Mitsubishi Chemical Corporation, Carbon black #45 (furnace black, DBP absorption 53 g / 100 cm 3 )

[0071] <Phosphorus-based stabilizer> Irgafos 168: Manufactured by BASF

Chem.

Chem.

[0072] <Hindered phenol-based stabilizer> AO-30: Manufactured by ADEKA

Chem.

Chem.

Chem.

[0073] <HALS-based stabilizer> Chimassorb 944LD: Manufactured by BASF ]>

Chem.

[0074] <Talc> 5000S: Micron White MW5000S, manufactured by Hayashi Kasei Co., Ltd., average particle size 5 μm

[0075] <Flame retardant> OP1230: Aluminum phosphinate salt, manufactured by Clariant Chemical, Exolit OP1230 OP1400: Metal phosphinate salt, manufactured by Clariant Chemical, Exolit OP1400

[0076] 2. Examples 1-11, Comparative Examples 1-11 <Compound> As shown in Tables 1 to 3, each component was weighed (the unit for each component is mass%), and the components other than glass fiber were blended in a tumbler. The mixture was then fed into a twin-screw extruder (Shibaura Machine Co., Ltd., TEM26SS) from the base and melted. After that, glass fiber was side-fed to produce polyamide resin pellets. The temperature setting of the twin-screw extruder was 280°C.

[0077] <Bending strength and bending modulus> After drying the polyamide resin pellets obtained by the above manufacturing method at 120°C for 4 hours, ISO tensile test specimens (4 mm thick) were injection molded using an injection molding machine (NEX140III, manufactured by Nissei Plastic Industrial Co., Ltd.) under the conditions of cylinder temperature 280°C, mold temperature 130°C, and molding cycle of 50 seconds. However, the cylinder temperature for Comparative Examples 10 and 11 was 300°C. In accordance with ISO 178, the bending strength (in MPa) and bending modulus (in GPa) were measured using the above ISO tensile test specimen (4 mm thick) under conditions of 23°C and 50% humidity. The results are shown in Tables 1 to 4.

[0078] <Charpy impact strength> In accordance with ISO 179-1 and 2, the above ISO tensile test specimen (4 mm thick) was used to test the notched and unnotched Charpy impact strength (unit: kJ / m²) using a 1 J hammer in an environment of 23°C and 50% humidity. 2 The following measurements were taken. The results are shown in Tables 1 to 4.

[0079] <Flame retardancy (UL94 test)> The pellets of the polyamide resin obtained by the above manufacturing method were dried at 120°C for 4 hours, and then combustion test pieces for UL with a length of 125 mm, a width of 13 mm, and a thickness of 1.5 mm were injection molded using an injection molding machine (manufactured by Japan Steel Works, Ltd., "J50ADS"). The cylinder temperature and the mold temperature were set at 280°C and 130°C, respectively. However, the cylinder temperature for Comparative Examples 10 and 11 was set at 300°C. The combustion test pieces for UL obtained by the above method were conditioned in a thermo-hygrostat at a temperature of 23°C and a humidity of 50% for 48 hours, and the UL94 test was conducted in accordance with the standard. The results are shown in Tables 1 to 4.

[0080] <CTI (Tracking Resistance Test)> The pellets of the polyamide resin composition obtained by the above manufacturing method were dried at 120°C for 4 hours, and then a flat plate of 100×100×3 mm was injection molded using an injection molding machine (manufactured by Nissei Plastic Industrial Co., Ltd., "NEX80"). The cylinder temperature and the mold temperature were set at 280°C and 130°C, respectively. However, the cylinder temperature for Comparative Examples 10 and 11 was set at 300°C. Using the flat plate obtained by the above method, the measurement was conducted in accordance with the test method IEC60112 standard. The measurement was carried out by changing the applied voltage every 25 V, and the maximum voltage at which no tracking occurred even when 50 or more drops of an electrolytic solution (0.2% aqueous ammonium chloride solution) were dropped between the electrodes was determined. The upper limit of the applied voltage was set at 600 V according to the standard.

[0081] <Appearance> The appearance of the ISO tensile test piece (4 mm thick) obtained above was visually evaluated. The evaluation was conducted by 5 experts and decided by a majority vote. A: It has a mirror finish and is good. B: Other than A above, for example, additives are bleeding out, part of the reinforcing fiber is protruding on the surface, and the appearance is cloudy.

[0082]

Table 1

[0083]

Table 2

[0084] [Table 3]

[0085] [Table 4]

[0086] As is clear from the results above, the resin composition of the present invention exhibited excellent physical properties and flame retardancy. In particular, the burning time was significantly reduced according to the UL-94 test (Examples 1-11). In contrast, when (D) no organic stabilizer was included (Comparative Example 1), or when an organic stabilizer was included but not the organic stabilizer specified in the present invention (Comparative Examples 3 and 4), the burning time of the molded product was prolonged. Furthermore, when (D) an organic stabilizer was included but in a large quantity (Comparative Example 2), the appearance was inferior. Furthermore, when the aliphatic polyamide resin content was high (Comparative Example 5), the burning time of the molded product was prolonged. (E) When the release agent content was high (Comparative Example 6), the flame retardancy was poor. The appearance was also inferior. (C) When no flame retardant was included (Comparative Example 7), the flame retardancy was inferior, and (C) when the flame retardant content was high (Comparative Examples 8 and 11), the appearance was inferior. (B) When the proportion of reinforcing fibers was high (Comparative Example 9), the appearance was also inferior. When the semi-aromatic polyamide resin did not contain more than 50 mol% of dicarboxylic acid units as straight-chain aliphatic chains with 4 to 7 carbon atoms (Comparative Example 10, Comparative Example 11), the appearance was inferior.

Claims

1. (A) 45-85% by mass of semi-aromatic polyamide resin, (B) 10-45% by mass of reinforcing fibers, (C) 1 to 10% by mass of phosphorus-based flame retardant, (D) 0.01 to 1% by mass of an organic stabilizer, (E) 0.01 to 1% by mass of release agent, (F) Consists of at least one additive other than the above in an amount of 0 to 25.0% by mass, A resin composition in which the sum of components (A) to (F) is 100.0% by mass, The (A) semi-aromatic polyamide resin contains diamine units and dicarboxylic acid units, and more than 50 mol% of the dicarboxylic acid units have linear aliphatic chains with 4 to 7 carbon atoms. The (D) organic stabilizer has a linear or branched alkyl group having 5 or fewer carbon atoms, The aliphatic polyamide resin content in the resin composition is less than 1% by mass. A resin composition, The above (A) includes a polyamide resin in which 70 mol% or more of the diamine units contained in the semi-aromatic polyamide resin are xylylenediamine units, The (B) reinforcing fiber includes glass fiber, The (C) phosphorus-based flame retardant comprises at least one compound represented by formula (I) and one compound represented by formula (II), The (D) organic stabilizer is a hindered phenol compound, A resin composition wherein the (E) release agent contains a higher fatty acid metal salt. 【Chemistry 1】 (In formula (I), R1 and R2 each independently represent a linear or branched alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms. M represents a calcium ion, an aluminum ion, a magnesium ion, or a zinc ion. m is a natural number representing the valency of M.) 【Chemistry 2】 (In formula (II), R4 and R5 each independently represent a linear or branched alkyl group having 1 to 6 carbon atoms, or an aryl group having 6 to 10 carbon atoms. R3 represents a linear or branched alkylene group having 1 to 10 carbon atoms, an arylene group having 6 to 10 carbon atoms, an alkylarylene group having 7 to 10 carbon atoms, or an arylalkylene group having 7 to 10 carbon atoms. M represents a calcium ion, an aluminum ion, a magnesium ion, or a zinc ion. n is a natural number representing the valence of M. n, a, and b are natural numbers that satisfy the relationship 2 × b = n × a.)

2. A pellet formed from the resin composition described in claim 1.

3. A molded article formed from the resin composition described in claim 1.

4. A molded article formed from the pellets described in claim 2.

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