JP2012214559A - Flame-retardant polyamide resin composition - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a flame-retardant polyamide resin composition, which has an excellent appearance with high rigidity and excellent surface smoothness, and has excellent moldability while securing extremely high flame retardancy.SOLUTION: The flame-retardant polyamide resin composition comprises: 100 pts.mass in total of 60-90 mass% of a polyamide resin (A) and 40-10 mass% of a halogen-free flame retardant (B); and 60-210 pts.mass of (C) a flat glass fiber having a BET specific surface area of 0.1 mm/g or more and a ratio of long diameter/short diameter of 1.5-10. The polyamide resin (A) includes a crystalline polyamide resin (a1) and an amorphous polyamide resin (a2), in which the mass ratio of the amorphous polyamide resin (a2) in the polyamide resin (A) is 0.1≤(a2)/(A)≤0.5. The halogen-free flame retardant (B) is composed of a reaction product (b3) of a phosphinate (b1) and/or a diphosphinate (b2), phosphoric acid and melamine.

Description

  The present invention relates to a polyamide resin composition excellent in mechanical strength and flame retardancy.

  Polyamide resins have excellent mechanical properties and heat resistance, and are therefore used in a wide variety of fields such as electric / electronics, automobiles, machinery, and building materials. Recently, resin substitution by metal substitution has progressed, and resin has required strength and rigidity equivalent to metal. In particular, advanced flame resistance is required for electrical components such as connectors, and home appliances such as housing parts for electrical devices represented by OA devices such as portable personal computers, word processors, electronic dictionaries, and mobile phones. The In order to make a resin flame-retardant, generally, a method of adding a halogen-based flame retardant or a triazine-based flame retardant or a method of depositing Mg on a resin are taken. However, halogen-based flame retardants are not preferred because they have adverse effects on the environment and the human body, such as corrosive halogen gases and harmful substances generated during combustion.

  For this reason, halogen-free triazine flame retardants have attracted attention and many studies have been made. In a system that does not contain a reinforcing material, the flame retardancy conforming to the UL94 V-0 standard can be achieved with a thickness of 1/32 inch. There is a problem that ignition occurs and the UL94 V-0 standard is not met.

  On the other hand, polyamide resin compositions containing a large amount of melamine phosphate, melamine pyrophosphate, or melamine polyphosphate, which are intumescent flame retardants, have been proposed, but mechanical properties and tracking resistance including toughness are also proposed. As a result, the electrical characteristics such as the above were deteriorated and could not be said to be satisfactory in practical use.

  Furthermore, a technology combining a phosphinate and a “reaction product of melamine and phosphoric acid” (for example, Patent Document 1), and a technology combining a phosphinate and a “reaction product of melamine and phosphoric acid” and a metal compound (For example, Patent Document 2) has been proposed, and it is known that a 1/16 inch molded product satisfies the flame retardant standard UL94V-0 standard. With this technology, it is possible to reduce the amount of flame retardant, and it is possible to improve mechanical properties such as toughness and electrical properties such as tracking resistance, but when inorganic fillers are highly blended to improve impact resistance, It has been difficult to obtain a polyamide resin composition capable of obtaining a molded article having high rigidity and good appearance while impairing operability such as melt kneading and maintaining flame retardancy.

  In Patent Document 3, as a polyamide resin to be contained, a polyamide resin that can be used in combination with a crystalline polyamide and an amorphous polyamide, and can obtain a molded body having a high rigidity and a good appearance while maintaining flame retardancy. Although the composition is disclosed, it is particularly satisfactory in terms of strength and rigidity to be used as a resin composition having a thin wall, high rigidity, good appearance and flame retardancy as various home appliance casings such as personal computers. It was not obtained.

JP 2004-263188 A JP 2007-23206 A JP 2010-077194 A

  The present invention has high rigidity, excellent surface smoothness, excellent appearance, extremely high flame retardancy, no generation of highly corrosive halogen gas during combustion, and excellent flame retardancy with excellent moldability An object is to provide a polyamide resin composition.

  As a result of diligent studies to solve the above-mentioned problems, the present inventor includes a crystalline polyamide resin and an amorphous polyamide resin as a polyamide resin, and contains a specific inorganic filler and a phosphinate at a specific ratio As a result, the present inventors have found that the above-mentioned problems can be solved and have reached the present invention.

  That is, the gist of the present invention is as follows.

(1) Polyamide resin (A) 60 to 90% by mass, flame retardant containing no halogen element (B) 40 to 10% by mass in total 100 parts by mass, and BET specific surface area of 0.1 mm ² / g or more / A flame retardant polyamide resin composition comprising 60 to 210 parts by mass of flat glass fiber (C) having a minor axis ratio of 1.5 to 10, wherein the polyamide resin (A) is a crystalline polyamide resin (a1) And the amorphous polyamide resin (a2), the mass ratio of the amorphous polyamide resin (a2) in the polyamide resin (A) is 0.1 ≦ (a2) / (A) ≦ 0.5, A flame retardant polyamide characterized in that the flame retardant (B) containing no halogen element comprises a phosphinate (b1) and / or a diphosphinate (b2) and a reaction product (b3) of phosphoric acid and melamine Resin composition.
(2) The blending ratio of the flame retardant (B) containing no halogen element is 10% by mass or more and less than 20% by mass with respect to (A) + (B), and the amorphous polyamide in the polyamide resin (A) The flame retardant polyamide resin composition according to (1), wherein the mass ratio of the resin (a2) is 0.4 ≦ (a2) / (A) ≦ 0.5.
(3) Further, (D) a phosphorus antioxidant or / and (E) a hindered phenol antioxidant is contained in a total of 0.1 to 1 part by mass with respect to a total of 100 parts by mass of (A) + (B). The flame-retardant polyamide resin composition according to any one of (1) to (3).
(4) Flame retardancy of (1) to (5), wherein the phosphinate (b1) is represented by the following general formula (I) and the diphosphinate (b2) is represented by the following general formula (II): Polyamide resin composition.
(Wherein R ₁ , R ₄ and R ₂ , R ₅ each represent a linear or branched C _{1 to} C ₁₆ alkyl, and R ₁ and R ₂ and R ₄ and R ₅ form a ring with each other; R ₃ represents linear or branched C _{1 to} C ₁₀ alkylene; M represents calcium or aluminum ion; m is 2 or 3; n is 1 or 3; x is 1 or 2; mx = 2n in formula (II)).

  According to the present invention, the rigidity is very high, the surface smoothness is good, the appearance is excellent, the flame retardancy is extremely high, no corrosive halogen gas is generated during combustion, and the moldability is excellent. A resin composition can be provided. Further, by using a combination of an amorphous polyamide resin and a flame retardant that does not contain a halogen element, even when a large amount of inorganic reinforcing material is blended, the blending amount of the flame retardant can be relatively reduced. Furthermore, by limiting the shape and specific surface area of the inorganic filler, the amount of the flame retardant can be relatively reduced, resulting in lower operability during melt kneading, lower moldability, and lower mechanical properties of the resin composition. Can be suppressed. .

The present invention will be specifically described below.
The polyamide resin used in the present invention includes a crystalline polyamide resin and an amorphous polyamide resin.

Crystallinity means that the value of the heat of fusion measured with a differential scanning calorimeter (DSC) at a heating rate of 16 ° C./min in a nitrogen atmosphere is greater than 1 cal / g.
Amorphous means that the value of heat of fusion measured with a differential scanning calorimeter (DSC) at a heating rate of 16 ° C./min in a nitrogen atmosphere is 1 cal / g or less.

  Examples of the crystalline polyamide resin include the following. That is, polycaproamide (nylon 6), polyhexamethylene adipamide (nylon 66), polytetramethylene adipamide (nylon 46), polyhexamethylene sebamide (nylon 610), polyhexamethylene dodecamide (nylon) 612), polyundecamethylene adipamide (nylon 116), polybis (4-aminocyclohexyl) methane dodecamide (nylon PACM12), polybis (3-methyl-4aminocyclohexyl) methane dodecamide (nylon dimethyl PACM12), poly Undecamethylene terephthalamide (nylon 11T), polyundecamethylene hexahydroterephthalamide (nylon 11T (H)), polyundecamide (nylon 11), polydodecamide (nylon 12), polytrimethyl Samethylene terephthalamide (nylon TMDT), polyhexamethylene isophthalamide (nylon 6I), polyhexamethylene terephthalamide / isophthalamide (nylon 6T / 6I), polymetaxylylene adipamide (nylon MXD6) and copolymers thereof, There is a mixture. Of these, nylon 6, nylon 66, copolymerized polyamides thereof, and mixed polyamides are particularly preferable. These crystalline polyamide resins preferably have a melting point of 160 to 320 ° C, more preferably 180 to 300 ° C, from the viewpoint of improving the heat resistance of the obtained flame-retardant polyamide resin composition.

  Examples of the amorphous polyamide resin include the following. That is, polycondensate of isophthalic acid / terephthalic acid / hexamethylenediamine / bis (3-methyl-4-aminocyclohexyl) methane, terephthalic acid / 2,2,4-trimethylhexamethylenediamine / 2,4,4-trimethyl Hexamethylenediamine polycondensate, isophthalic acid / bis (3-methyl-4-aminocyclohexyl) methane / ω-laurolactam polycondensate, isophthalic acid / terephthalic acid / hexamethylenediamine polycondensate, isophthalic acid / Polycondensate of 2,2,4-trimethylhexamethylenediamine / 2,4,4-trimethylhexamethylenediamine, isophthalic acid / terephthalic acid / 2,2,4-trimethylhexamethylenediamine / 2,4,4-trimethyl Hexamethylenediamine polycondensate, isophthalic acid / bis (3 Polycondensate of methyl-4-aminocyclohexyl) methane / .omega.-laurolactam can be cited. Also included are those in which the benzene ring of the terephthalic acid component and / or isophthalic acid component constituting these polycondensates is substituted with an alkyl group or a halogen atom. Furthermore, two or more of these amorphous polyamides can be used in combination. Preferably, a polycondensate of isophthalic acid / terephthalic acid / hexamethylenediamine, a polycondensate of isophthalic acid / terephthalic acid / hexamethylenediamine / bis (3-methyl-4-aminocyclohexyl) methane, or terephthalic acid / 2, Polycondensate of 2,4-trimethylhexamethylenediamine / 2,4,4-trimethylhexamethylenediamine or polycondensation of isophthalic acid / terephthalic acid / hexamethylenediamine / bis (3-methyl-4-aminocyclohexyl) methane And a mixture of terephthalic acid / 2,2,4-trimethylhexamethylenediamine / 2,4,4-trimethylhexamethylenediamine polycondensate. Particularly preferred is a polycondensate of isophthalic acid / terephthalic acid / hexamethylenediamine, a polycondensate of isophthalic acid / terephthalic acid / hexamethylenediamine / bis (3-methyl-4-aminocyclohexyl) methane, or a mixture thereof. These amorphous polyamide resins preferably have a glass transition temperature of 80 to 200 ° C. from the viewpoint of improving the heat resistance of the obtained flame-retardant polyamide resin composition and improving processability. More preferably, it is 170 degreeC. When the glass transition temperature is less than 80 ° C., the flame retardant polyamide resin composition is solidified when it is molded, and therefore, it is not preferable because a mold release failure occurs or a molding cycle becomes long. When the temperature exceeds 200 ° C., when the flame-retardant polyamide resin composition is molded and processed, solidification is too early, and appearance defects such as sink marks and glass floating tend to occur, and the melt viscosity during kneading is high. Therefore, uniform kneading becomes difficult, which is not preferable.

  In consideration of relaxation of the crystallinity of the polyamide component, the heat of fusion of the amorphous polyamide resin is 1 cal / g when measured at a heating rate of 16 ° C./min in a nitrogen atmosphere using an elemental scanning calorimeter. Must be:

  The compounding amount of the polyamide resin needs to be 60 to 90% by mass in the total amount ((A) + (B) = 100% by mass) of the flame retardant not containing (A) the polyamide resin and (B) halogen element. There is. If it is less than 60% by mass, the operability and molding processability at the time of extrusion deteriorate. If it exceeds 90 mass%, the flame retardancy is inferior, which is not preferable.

  The polyamide resin is blended with a crystalline polyamide resin and an amorphous polyamide resin, and the mass ratio (a2) / (A) of the amorphous polyamide resin in the polyamide resin is 0.1 to 0.5. There is a need. When the inorganic filler (fibrous reinforcing material and plate-like silicate) is blended at a high concentration as in the present invention when it is less than 0.1, the surface smoothness is lost and it looks like a notebook computer casing. It cannot be used for applications that require safety. When an inorganic filler is blended at a high concentration exceeding 0.5, these amorphous polyamides generally have a high glass transition temperature, so a smooth surface cannot be obtained unless molded with a high temperature mold. Further, since the crystallinity is lowered, the molding cycle in injection molding or the like is extended and the productivity is deteriorated.

  The relative viscosity of the polyamide resin used in the present invention is not particularly limited, but the relative viscosity measured with 96 wt% concentrated sulfuric acid as a solvent at a temperature of 25 ° C. and a concentration of 1 g / dl is 1.5-4. A range of 0 is preferred. If the relative viscosity is less than 1.5, the viscosity is low, so that the take-up property after melt-kneading becomes difficult, and desired physical properties cannot be obtained in the composition. On the other hand, if the viscosity is larger than 4.0, the flowability at the time of molding processing is poor due to high viscosity, and the time until the resin is filled in the mold becomes long, so that the polyamide resin having a relative viscosity of 1.5 to 4.0 In contrast, the resin temperature at the flow front is lowered, that is, the resin bonding at the weld portion is deteriorated, and the weld strength is lowered. From the viewpoints of ensuring fluidity, transferability of the resin to the mold, appearance of the molded product, and weld strength, it is preferable to use a polyamide resin having a relative viscosity of 1.8 to 3.0.

  Flame retardants that do not contain halogen elements include phosphinates and diphosphinates and their polymers, melamine polyphosphate, melamine cyanurate, red phosphorus, phosphate ester, condensed phosphate ester, phosphazene compound, metal hydroxide, etc. In the present invention, from the viewpoint of stability during processing, dispersibility in kneading with a resin, and flame retardant effect, either or both of the phosphinic acid salt (b1) and diphosphinic acid salt (b2) are added. It is necessary to use it. Phosphinate is produced in an aqueous solution using phosphinic acid and metal carbonate, metal hydroxide or metal oxide and exists essentially as a monomer, but depending on the reaction conditions, the degree of condensation is 1 to It may also exist in the form of 3 polymeric phosphinates. Examples of the metal component include calcium carbonate, magnesium ion, aluminum ion, and / or metal carbonate, metal hydroxide or metal oxide containing zinc ion.

  Such a phosphinate (b1) is represented by the following general formula (I), and the diphosphinate (b2) is represented by the following general formula (II).

In which R ₁ , R ₄ and R ₂ , R ₅ are each linear or branched C ₁ -C ₁₆ alkyl, preferably C ₁ -C ₈ alkyl, in particular methyl, ethyl, n-propyl, isopropyl, n -Butyl, tert-butyl, n-pentyl, n-octyl, phenyl, more preferably ethyl, and R ₁ and R ₂ and R ₄ and R ₅ may form a ring with each other. R ₃ is linear or branched C ₁ -C ₁₀ alkylene, especially methylene, ethylene, n-propylene, isopropylene, isopropylidene, n-butylene, tert-butylene, n-pentylene, n-octylene, n-dodecylene. Arylene, especially phenylene, naphthylene, alkylarylene, especially methylphenylene, ethylphenylene, tert-butylphenylene, methylnaphthylene, ethylnaphthylene, tert-butylnaphthylene; arylalkylene, especially phenylmethylene, phenylethylene, phenylpropylene, phenylbutylene , M is calcium, aluminum, magnesium, zinc, preferably aluminum, zinc, more preferably aluminum, m is 2 or 3, n is 1 or 3, and x is 1 or 2. In the formula (II), mx = 2n. )

  Phosphinic acid suitable as a component of the phosphinic acid salt includes dimethylphosphinic acid, ethylmethylphosphinic acid, diethylphosphinic acid, methyl-n-propylphosphinic acid, isobutylmethylphosphinic acid, octylmethylphosphinic acid, methylphenylphosphinic acid and And diphenylphosphinic acid, preferably diethylphosphinic acid).

  Specific examples of the phosphinic acid salt represented by the above formula (I) include, for example, calcium dimethylphosphinate, magnesium dimethylphosphinate, aluminum dimethylphosphinate, zinc dimethylphosphinate, calcium ethylmethylphosphinate, ethylmethylphosphinic acid. Magnesium, aluminum ethylmethylphosphinate, zinc ethylmethylphosphinate, calcium diethylphosphinate, magnesium diethylphosphinate, aluminum diethylphosphinate, zinc diethylphosphinate, calcium methyl-n-propylphosphinate, methyl-n-propylphosphinic acid Magnesium, aluminum methyl-n-propylphosphinate, zinc methyl-n-propylphosphinate, calcium methylphenylphosphinate Magnesium methylphenyl phosphinate, aluminum methylphenyl phosphinate, methyl phenyl phosphinate, zinc, calcium diphenyl phosphinate, magnesium diphenyl phosphinate, aluminum diphenyl phosphinate, and zinc diphenyl phosphinate and the like.

  Examples of the diphosphinic acid suitable as a component of the diphosphinic acid salt include methanedi (methylphosphinic acid) and benzene-1,4-di (methylphosphinic acid).

  Specific examples of the diphosphinic acid salt represented by the above formula (II) include, for example, methanedi (methylphosphinic acid) calcium, methanedi (methylphosphinic acid) magnesium, methanedi (methylphosphinic acid) aluminum, methanedi (methylphosphinic acid) Zinc, benzene-1,4-di (methylphosphinic acid) calcium, benzene-1,4-di (methylphosphinic acid) magnesium, benzene-1,4-di (methylphosphinic acid) aluminum, benzene-1,4- Di (methylphosphinic acid) zinc is mentioned.

  In the present invention, particularly preferably used from the viewpoint of flame retardancy and electrical properties, the phosphinate is aluminum diethylphosphinate, zinc diethylphosphinate, more preferably aluminum diethylphosphinate, Are methanedi (methylphosphinic acid) aluminum and methanedi (methylphosphinic acid) zinc. Exolit OP1230, Exolit OP1311, Exolit OP1312, Exolit OP1314 manufactured by Clariant, Inc., which is commercially available as a mixture thereof, can be used preferably.

  The phosphinic acid salt, diphosphinic acid salt, and a mixture thereof have an average particle diameter (D50) in terms of mechanical properties and appearance of the molded product obtained by molding the flame-retardant polyamide resin composition of the present invention. Hereinafter, a powder having a particle size of 100 μm or less, preferably 50 μm or less, may be used. Use of a powder having a particle size of 0.5 to 30 μm is particularly preferable because not only high flame retardancy is exhibited but also the strength of the molded product is remarkably increased. The particle size in the present invention is defined as a particle size value when the weight cumulative distribution is 50% when the particle size distribution is measured using a particle size distribution measuring device such as a laser scattering particle size distribution meter.

  In addition to the phosphinate (b1) and the diphosphinate (b2), the flame retardant (B) containing no halogen element needs to be used in combination with the reaction product (b3) of phosphoric acid and melamine.

  When a reaction product of phosphoric acid and melamine is used as a flame retardant (B) containing no halogen element, a flame retardant effect can be obtained more efficiently. For example, the flame retardant level is the same as V-0. Even if it exists, the improvement of a flame retardance performance, such as shortening the afterflame time, is seen. Moreover, since the freedom degree of a flame retardant mix | blend increases in control of a flame retardant performance, even if it is the same flame retardant level, it is possible to reduce the usage-amount of a flame retardant.

  Of the flame retardant (B) containing no halogen element, the blending ratio of the reaction product of phosphoric acid and melamine is preferably 10 to 50% by mass of the total amount of the flame retardant (B). If the amount is too large, the operability at the time of melt kneading is remarkably deteriorated, and the blending ratio of phosphinic acid and diphosphinic acid is relatively lowered, so that the flame retardancy is lowered. On the other hand, if the amount is too small, the effect of using the reaction product of phosphoric acid and melamine is weakened, and the flame retardancy is lowered.

  The reaction product (b3) of phosphoric acid and melamine is produced by a reaction between a hydroxyl group of phosphoric acid and an amino group of melamine, and is obtained by a substantially equimolar reaction of phosphoric acid and melamine. Is. In the present specification, unless otherwise specified, phosphoric acid is orthophosphoric acid, polyphosphoric acid obtained by dehydration condensation of orthophosphoric acid (for example, pyrophosphoric acid, triphosphoric acid, tetraphosphoric acid, etc.), phosphorous acid, hypophosphorous acid. It means to include acid and metaphosphoric acid. Hereinafter, the reaction product of phosphoric acid and melamine shall be referred to as melamine phosphate. For example, melamine orthophosphate means a reaction product of orthophosphoric acid and melamine, and melamine polyphosphate is a reaction between polyphosphoric acid and melamine. It shall mean the product. In addition, melamine phosphate is intended to include reaction products of various phosphoric acids and melamine, such as melamine orthophosphate, melamine polyphosphate (for example, melamine pyrophosphate, melamine triphosphate, melamine tetraphosphate, etc.) ), Melamine phosphite, melamine hypophosphite, melamine metaphosphate, and mixtures thereof. The melamine polyphosphate is a general term for a melamine phosphate condensate, and indicates each simple substance such as melamine pyrophosphate, melamine triphosphate, melamine tetraphosphate, or a mixture thereof. Preferred melamine phosphates are melamine orthophosphate, melamine polyphosphate, or mixtures thereof, more preferably melamine polyphosphate.

  There is no particular restriction on the production method of melamine phosphate, but usually, a predetermined phosphoric acid aqueous solution and melamine aqueous solution are mixed well to form both reaction products into fine particles, followed by filtration, washing and drying. Can be manufactured. In the production method of melamine polyphosphate, melamine may be reacted with polyphosphoric acid as described above, or melamine phosphate may be condensed. In particular, melamine polyphosphate can be obtained by heat condensation of melamine orthophosphate in a nitrogen atmosphere.

  Melamine phosphate can also be obtained as a commercial product. For example, for melamine polyphosphate, Ciba Specialty Chemicals; Melapur 200/70, Nissan Chemicals PMP-100, Welchem MPP, etc. can be used.

  As the melamine phosphate, a powder obtained by pulverizing to a particle size of 100 μm or less, preferably 50 μm or less, may be used in view of mechanical properties and appearance of a molded product obtained by molding the composition of the present invention. Use of a powder having a particle size of 0.5 to 20 μm is particularly preferable because not only high flame retardancy is exhibited but also the strength of a molded product is remarkably increased.

  The blending amount of the polyamide resin and the flame retardant containing no halogen element is the total amount of (A) the polyamide resin and (B) the flame retardant containing no halogen element ((A) + (B) = 100 mass%) It is necessary to mix 10 to 40% by mass. When the blending amount of the flame retardant is less than 10% by mass, the flame retardancy is inferior, and when it exceeds 40% by mass, the operability during extrusion, the mechanical strength is lowered, and the mold contamination is not preferable.

  In this invention, the compounding quantity of the flame retardant (B) which does not contain a halogen element can be reduced by increasing the ratio of the amorphous polyamide (a2) contained in a polyamide resin (A). That is, when the amorphous polyamide resin (a2) is used in a ratio of 0.4 ≦ (a2) / (A) ≦ 0.5, the flame retardant (B) containing no halogen element is added in an amount of 10% by mass or more and 20% by mass. It can be used at a ratio of less than mass%. Of course, it does not preclude use at 20 mass% or more and 40 mass% or less. By making the amount of the flame retardant small, it is possible to more effectively prevent deterioration in operability during extrusion, reduction in mechanical strength, and mold contamination, which are likely to occur by adding a flame retardant. This is because the benzene ring of phthalic acid formed in the skeleton of the amorphous polyamide (A2) is very stable and difficult to burn.

  On the other hand, when the proportion of the amorphous polyamide (a2) is reduced, the amorphous polyamide resin (a2) is contained in a large amount at a ratio of 0.4 ≦ (a2) / (A) ≦ 0.5 as described above. Compared to, there is a tendency that a larger amount of flame retardant is required. That is, when the ratio of the amorphous polyamide (a2) contained in the polyamide resin (A) is 0.1 ≦ (a2) / (A) <0.4, the flame retardant (B) containing no halogen element is What is necessary is just to make it use in the ratio of 20-40 mass%.

The flat glass fiber (C) used in the present invention is required to have a BET specific surface area of 0.1 mm ² / g or more measured by nitrogen adsorption using a constant volume method, and is 0.125 mm ² / g. It is preferable that it is above, and it is more preferable that it is 0.15 mm ² / g or more. If it is less than 0.1 mm ² / g, mechanical strength and flame retardancy tend to be insufficient. Moreover, when the molded object obtained is a thin molded object, there exists a tendency for remarkable curvature to generate | occur | produce. In actual use, the molded body absorbs moisture in the atmosphere, and the degree of warpage becomes worse. The cross-sectional shape of the flat glass fiber is an ellipse, an ellipse, a rectangle, a rectangle or the like, and is defined by a long diameter defined by the maximum length passing through the center point and a minimum length passing through the center point. The shape is not particularly limited as long as the shape has a minor axis. In order to reduce the warpage peculiar to the glass fiber-containing polyamide resin composition, flat fibers having a major axis / minor axis ratio of 1.5 to 10, preferably 2.0 to 6.0 are used. . If the ratio of major axis / minor axis is less than 1.5, the effect of improving the mechanical strength is poor, and if it exceeds 10, it is difficult to produce the glass fiber itself. Further, the glass fiber can be selected from long fiber type roving, short fiber type chopped strand, milled fiber and the like. The glass fiber that has been surface-treated with a silane coupling agent such as epoxy or aminosilane may be used.

  The flat glass fiber has an average length of 1 to 15 mm, preferably 2 to 10 mm. Here, the average length refers to an average of 20 pieces obtained by observing flat glass fibers with a microscope and measuring with reference to a microscale. If the average length of the fibers is longer than 15 mm, the flow of the resin is deteriorated at the time of resin molding, the workability is deteriorated, and if it is shorter than 1 mm, sufficient mechanical strength cannot be secured.

  As the glass fiber, in addition to the flat glass fiber, a glass fiber having a round cross section may be used in combination as long as it does not impair the mechanical strength, flame retardancy improvement, and warpage reduction effect of the flat glass fiber.

  The blending amount of the flat glass fiber (C) is 60 to 210 parts by mass, preferably 70 to 200 parts by mass with respect to 100 parts by mass of the resin composition comprising (A) a polyamide resin and (B) a flame retardant containing no halogen element. Part. If it is less than 60 parts by mass, the strength, rigidity and heat resistance are not satisfied, and if it exceeds 210 parts by mass, melt kneading workability and molding processability are deteriorated. Further, the flat glass fiber having a flat cross section has a surface area per unit area larger than that using a glass fiber having a circular glass cross section, and the flat glass fiber occupies the surface of the molded product after molding the polyamide resin composition. And the flame retardancy of the molded product tends to increase due to the non-flammable properties of the flat glass fiber. Thus, flat glass fiber will be in the state which covers the molded object surface, and the shielding effect of a heat | fever and oxygen is large and a flame retardance improves notably. With the effect of improving the flame retardancy by using flat glass, the content of flame retardant in the obtained flame retardant polyamide resin composition can be reduced, and the extrudability and moldability of the obtained flame retardant polyamide resin composition can be reduced. In addition, the brittleness is improved, and the strength and rigidity, particularly weld strength, are improved.

  The flame-retardant polyamide resin composition can be further improved in moldability by containing (D) a phosphorus-based antioxidant or / and (E) a hindered phenol-based antioxidant.

  (D) The phosphorus antioxidant may be an inorganic compound or an organic compound, and is not particularly limited. Preferred phosphorus compounds include inorganic phosphates such as monosodium phosphate, disodium phosphate, trisodium phosphate, sodium phosphite, calcium phosphite, magnesium phosphite, manganese phosphite, and triphenylphosphine. Phyto, trioctadecyl phosphite, tridecyl phosphite, trinonylphenyl phosphite, diphenylisodecyl phosphite, bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite (“Adeka Stab PEP -36 ", molecular weight 633), bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite (" ADK STAB PEP-24G ", molecular weight 604), tris (2,4-di-tert-butylphenyl) ) Phosphite, Jis Allyl pentaerythritol diphosphite (“Adekastab PEP-8”, molecular weight 733), bis (nonylphenyl) pentaerythritol diphosphite (“Adekastab PEP-4C”, molecular weight 633), tetra (tridecyl-4,4′-isopropi Examples thereof include organic phosphorus compounds such as redene diphenyl diphosphite and 2,2-methylenebis (4,6-di-tert-butylphenyl) octyl phosphite, which can be used alone or in a mixture thereof.

  In general, there are fatty acid amides (stearic acid amide, etc.) as additives for improving the mold releasability in injection molding, but these compounds are flammable. Decrease. Usually, antioxidants such as phosphorus-based antioxidants are used for prescription to suppress resin degradation and color degradation due to heat, but are not used for the purpose of imparting releasability. It has been found that by using a phosphorus-based antioxidant, not only the original antioxidant function but also the mold releasability can be improved without deteriorating the flame retardant properties of the flame retardant. In particular, a phosphorus-based antioxidant having a pentaerythritol diphosphite skeleton and having a molecular weight of 600 or more and less than 800, such as bis (2,6-di-tert-butyl-4-methylphenyl) pentaerythritol diphosphite (“Adeka Stab”). PEP-36 ", molecular weight 633), bis (2,4-di-tert-butylphenyl) pentaerythritol diphosphite (" ADK STAB PEP-24G ", molecular weight 604), tris (2,4-di-tert-butyl) Phenyl) phosphite, distearyl pentaerythritol diphosphite (“Adekastab PEP-8”, molecular weight 733), bis (nonylphenyl) pentaerythritol diphosphite (“Adekastab PEP-4C”, molecular weight 633) are particularly preferred. Among these, PEP-36 and PEP-24G, which are excellent in heat resistance, can be most suitably used.

  The phosphorus-based antioxidant is easily mixed with the phosphinic acid salt and diphosphinic acid salt which are flame retardants used in the present invention and prevents decomposition of the flame retardant, so that the flame retardancy is not impaired. Moreover, in order to prevent the molecular weight fall of a polyamide resin, the resin composition excellent in the operativity at the time of an extrusion process, a moldability, and a mechanical physical property can be obtained. In particular, a dramatic effect can be obtained in releasability during molding and reduction of gas generated during molding. For example, when continuous injection molding is performed, the gas vent of the mold is not easily clogged, and even if long-term continuous molding is performed, molding defects do not occur, and the number of mold cleanings can be reduced.

(E) A hindered phenolic antioxidant is at least one position containing at least one phenol group, the aromatic part of which is directly adjacent to the carbon having a phenolic hydroxyl group as a substituent, preferably both An organic compound that is substituted at a position. The substituent adjacent to the hydroxyl group is an alkyl radical suitably selected from alkyl groups having 1 to 10 carbon atoms, preferably a tertiary butyl group. The molecular weight of the hindered phenol is suitably at least about 260, preferably at least about 500, more preferably at least about 600. Most preferred is a hindered phenol having low volatility at high temperature, particularly low volatility at the processing temperature used for molding the compound, and heated from room temperature to 400 ° C. at a heating rate of 10 ° C./min. It can also be further characterized as having a 10% TGA weight loss temperature of at least 290 ° C, more preferably at least 300 ° C, most preferably 310 ° C.
For example, triethylene glycol-bis [3- (3-tert-butyl-5-methyl-4-hydroxyphenyl) propionate, 4,4′-butylidenebis (3-methyl-6-tert-butylphenol), 1,6-hexane Diol-bis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate, 2,4-bis- (n-octylthio) -6- (4-hydroxy-3,5-di-t -Butylanilino) -1,3,5-triazine, pentaerythrityl-tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], 2,2-thio-diethylenebis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate], octadecyl-3- (3,5-di-t-butyl-4-hydroxyphenyl) Propionate, 2,2-thiobis (4-methyl-6-1-butylphenol), N, N′-hexamethylenebis (3,5-di-t-butyl-4-hydroxy-hydroxynamamide), 3, 5-di-t-butyl-4-hydroxy-benzylphosphonate-diethyl ester, 1,3,5-trimethyl-2,4,6-tris (3,5-di-butyl-4-hydroxybenzyl) Benzene, ethyl calcium bis (3,5-di-t-butyl-4-hydroxybenzylsulfonate, tris- (3,5-di-t-butyl-4-hydroxybenzyl) -isocyanurate, 2,6- Di-t-butyl-p-cresol, butylated hydroxyanisole, 2,6-di-t-butyl-4-ethylphenol, stearyl-β- (3,5-di-t-butyl) -4-hydroxyphenyl) propionate, 2,2'-methylenebis- (4-methyl-6-tert-butylphenol), 2,2'-methylene-bis- (4-ethyl-6-tert-butylphenol), 4, 4'-thiobis- (3-methyl-6-tert-butylphenol), octylated diphenylamine, 2,4-bis [(octylthio) methyl] -O-cresol, isooctyl-3- (3,5-di-t- Butyl-4-hydroxyphenyl) propionate, 4,4′-butylidenebis (3-methyl-6-tert-butylphenol, 3,9-bis [1,1-dimethyl-2- [β- (3-tert-butyl-) 4-hydroxy-5-methylphenyl) propionyloxy] ethyl] 2,4,8,10-tetraoxaspiro [5,5] undecane, 1,1,3-tris 2-methyl-4-hydroxy-5-tert-butylphenyl) butane, 1,3,5-trimethyl-2,4,6-tris (3,5-di-tert-butyl-4-hydroxybenzyl) benzene, Bis [3,3′-bis- (4′-hydroxy-3′-T-butylphenyl) butyric acid] glycol ester, 1,3,5-tris (3 ′, 5′-di-t-butyl- 4′-hydroxybenzyl) -sec-triazine-2,4,6- (1H, 3H, 5H) trione, d-α-tocopherol and the like. These can be used alone or as a mixture thereof. Suitable hindered phenol compounds include Irganox 1010 and Irganox 1098 from Ciba Specialty Chemicals.

  Hindered phenolic antioxidants tend to slightly reduce the flame retardancy, but the flame retardants used in the present invention are phosphinates, diphosphinates, and the addition of phosphoric acid and melamine condensates is preferred. Can be prevented with high efficiency, and a polyamide resin composition excellent in operability, moldability, and mechanical properties during extrusion can be obtained. In particular, when continuous injection molding is performed, the gas vent of the mold is not easily clogged, and even if long-term continuous molding is performed, molding defects do not occur, and the number of mold cleanings can be reduced.

  These antioxidants can be used either alone or in combination, but when used together, a synergistic effect occurs, and a polyamide resin composition excellent in operability, moldability, and mechanical properties during extrusion can be obtained. it can.

  (D) Phosphorous antioxidant and / or (E) hindered phenolic antioxidant are (A) and (B) with respect to a total of 100 mass parts, and the sum of (D) and (E) is 0.00. It is necessary to be 01 to 5 parts by mass, and preferably 0.05 to 4 parts by mass. If the amount is too large, stability during extrusion processing, moldability, and mechanical properties will be reduced.If the amount is too small, mold release from the mold during molding and mold gas vent clogging will occur. Continuous injection molding becomes difficult.

  In the present invention, as an optional component, at least one compound selected from the group consisting of aliphatic amines, fatty acid metal salts, ethylenebisamide compounds, and aliphatic amides can be used. Even if this component is not present, the object of the present invention can be achieved, but this component can be added to improve fluidity and releasability. Among these, a silicone compound that contributes to flame retardancy is preferable, and silicone oil is most suitable. As addition amount, it is 0.05-2 mass parts with respect to a total of 100 mass parts of (A) and (B), Preferably it is 0.1-1.5 mass parts, More preferably, it is 0.1-1 mass. Part.

  Silicone oil is an organosilicon compound having a siloxane bond as a skeleton and an organic group or the like directly bonded to silicon. As an organic group directly bonded to silicon, a methyl group, an ethyl group, a phenyl group, a vinyl group, a trifluoropropyl group, and a combination thereof are known, but a known silicone oil having these is used without any particular limitation. it can. Some organic groups were substituted with substituents having epoxy groups, amino groups, polyether groups, carboxyl groups, mercapto groups, ester groups, chloroalkyl groups, alkyl groups having 3 or more carbon atoms, hydroxyl groups, and the like. Silicone oil can also be used.

  Specific examples of the silicone oil include dimethyl silicone oil, phenylmethyl silicone oil, alkyl-modified silicone oil, fluorosilicone oil, polyether-modified silicone oil, aliphatic ester-modified silicone oil, amino-modified silicone oil, carboxylic acid-modified silicone oil, Examples include oily silicones such as carbinol-modified silicone oil, epoxy-modified silicone oil, and mercapto-modified silicone oil.

  The flame-retardant polyamide resin composition of the present invention includes other components such as colorants such as pigments and dyes, heat stabilizers, weather resistance improvers, nucleating agents, plasticizers, release agents, and the like within a range that does not impair the purpose. Additives such as molds and antistatic agents, and other resin polymers can be added.

  The method for producing the flame-retardant polyamide resin composition of the present invention is not particularly limited, but it is preferably melt-kneaded at a temperature of 200 to 350 ° C. using a twin-screw extruder, and the flame retardancy and mechanical properties are improved. In order to achieve both, it is preferable to add the inorganic filler and degas it under reduced pressure after sufficiently melting and mixing raw materials other than the inorganic filler.

  The flame-retardant polyamide resin composition of the present invention can be molded by a known method such as injection molding, extrusion molding, blow molding, etc., for example, connectors, coil bobbins, breakers, electromagnetic switches, holders, plugs, switches, etc. It is molded into various molded products for electric, electronic, and automotive applications, as well as casing parts of electric devices represented by OA devices such as portable personal computers and word processors. In particular, a casing used for thin-wall molding can be suitably used by taking advantage of mechanical strength and flame retardancy.

  Next, the present invention will be described more specifically with reference to examples. The materials used and the evaluation method fees in the examples and comparative examples are as follows.

1. Materials used (1) Polyamide resin (i) Crystalline polyamide resin Polyamide 66: (melting point 265 ° C., relative viscosity 2.4, heat of fusion 21 cal / g; 24AD1 manufactured by Rhodia), hereinafter referred to as “PA66”.
Polyamide 6: (melting point 220 ° C., relative viscosity 1.9, heat of fusion 18 cal / g; A1012 manufactured by Unitika Ltd.), hereinafter referred to as “PA6”.
(Ii) Amorphous polyamide resin: Polycondensate of isophthalic acid / terephthalic acid / hexamethylenediamine / bis (3-methyl-4aminocyclohexyl) methane (glass transition temperature 125 ° C., relative viscosity 1.9, heat of fusion 0 .1 cal / g; CX-3000 manufactured by Unitika Ltd.), hereinafter referred to as “CX-3000”.
-Polycondensate of isophthalic acid / terephthalic acid / hexamethylenediamine (glass transition temperature 138 ° C., relative viscosity 2.0, heat of fusion 0.1 cal / g; X21 manufactured by Mitsubishi Engineering Plastics), hereinafter referred to as “X21” .

(2) Flame retardant (i) Phosphinate / diethylphosphinate aluminum (particle size 20 μm), hereinafter referred to as “DEPAL”.
(Ii) Reaction product of phosphoric acid and melamine Melamine polyphosphate (particle size 20 μm; Melapur 200/70 manufactured by Ciba Specialty Chemicals), hereinafter referred to as “Melapur”.
(Iii) Other flame retardants: Melamine cyanurate (particle size: 8 μm; MC25 manufactured by Ciba Specialty Chemicals), hereinafter referred to as “MC25”.

(3) Glass fiber (i) Flat glass fiber-Flat glass fiber having an oval cross section (fiber length 3 mm, major axis to minor axis ratio 4, specific surface area 0.14 mm ² / g, silane-based surface treatment: CSG3J manufactured by Nittobo Co., Ltd. -820S), hereinafter referred to as "flat GF1".
-Flat glass fiber having an oval cross section (fiber length 3 mm, major / minor diameter ratio 4, specific surface area 0.09 mm ² / g, silane-based surface treatment: CSG3PA820S manufactured by Nittobo Co., Ltd.), hereinafter referred to as “flat GF2”.
(Ii) Non-flat glass fiber / glass fiber having a circular cross section (fiber length 3 mm, average fiber diameter 10 μm, specific surface area 0.15 mm ² / g
: 03JAFT69 manufactured by Asahi Fiber Glass Co., Ltd.), hereinafter referred to as “circular GF”.

(4) Antioxidant (i) Phosphorous antioxidant, bis (2,6-di-t-butyl-4-methylphenyl) pentaerythritol diphosphite (Adeka Stab PEP-36 manufactured by Adeka), hereinafter referred to as “PEP” -36 ".
(Ii) hindered phenolic antioxidant pentaerythrityl tetrakis [3- (3,5-di-t-butyl-4-hydroxyphenyl) propionate] (Irganox 1010 manufactured by Ciba Specialty Chemicals), hereinafter referred to as “Irganox” Call it.

(5) Silicone oil / Methylphenyl silicone oil (GE Toshiba Silicone TSF4300)

2. Evaluation a) Operability at the time of melt-kneading Using a twin screw extruder (TEM37 manufactured by Toshiba Machine) provided with a three-hole die, cylinder temperature 280 ° C., screw rotation speed 200 rpm, discharge rate 35 kg / h, strand take-up speed When 10 kg was produced under the condition of 40 m / min, the condition of the strand was visually confirmed. When the strands were not cut at the time of operation, “○” was assigned, and “×” was assigned when the strand was cut once. Rank "O" was judged as good operability and was accepted.

b) Bending strength and flexural modulus Using a FANUC injection molding machine (α-100iA), a test piece (length 150 mm, width 10 mm, thickness 3 mm) at a resin temperature of 280 ° C. and a mold temperature of 100 ° C. with a single point gate. Was measured according to ASTM D790. A bending strength of 250 MPa or more and a bending elastic modulus of 12 GPa or more were accepted.

c) Flame retardancy Using a FANUC injection molding machine (α-100iA), a test piece was molded at a resin temperature of 280 ° C. and a mold temperature of 100 ° C., and UL94 shown in Table 1 (specified by Under Writers Laboratories Inc., USA) Measured according to the evaluation criteria of The thickness of the test piece was 1/32 inch (about 0.8 mm). Here, V-1 or higher was regarded as acceptable. Moreover, the total afterflame time at the time of a flame retardance measurement was also shown. For example, even if the flame retardancy level is the same V-0, a shorter total afterflame time indicates better flame retardancy.

In addition, the flame retardant level which does not correspond to any of V-0 to V-2 shown in Table 1 is displayed as “V-not”. “V-not” indicates no flame retardancy.

d) Releasability during continuous molding With a FANUC injection molding machine (α-100iA), at a resin temperature of 280 ° C. and a mold temperature of 100 ° C., in a cycle of 10 seconds, a shallow cup shape (wall thickness 1.5 mm, When the molded product was continuously molded for 500 shots using an outer diameter of 40 mm and a depth of 30 mm, the presence or absence of traces on the protruding pins of the 451 to 500th shot molded products was visually observed. The case where 5 or more pin marks were recognized was ranked as “x”, the case where 1 to 4 pin marks were recognized as “◯”, and the case where no marks were recognized as “◎”. The ranks “◯” and “◎” indicate good releasability, and are accepted.

e) Clogging of gas vent during continuous molding After completion of molding in d), visually check the gas vent with a depth of 3 μm and a width of 1 mm. Those with no clogging were ranked as “○”. Rank “○” was accepted.

f) Stability of Stability The presence or absence of traces of the protruding pin of the molded product was visually observed in the same manner as d) except that molding was performed in a cycle of 5 minutes. The case where 5 or more pin marks were recognized was ranked as “x”, the case where 1 to 4 pin marks were recognized as “◯”, and the case where no marks were recognized as “◎”. Ranks “◯” and “◎” indicate good retention stability, and were accepted.

g) Surface Roughness An average surface roughness (μm) of an arbitrary 10 portion using a surface roughness measuring instrument (Surfcoder SE-3400) manufactured by Kosaka Laboratory, Ltd. using a flat plate of 50 mm × 90 mm × 2 mm. ) Was measured. 20 μm or less was regarded as acceptable.

h) Flexural modulus of weld part Test piece (length: 150 mm, width: 10 mm, thickness at a resin temperature of 280 ° C., mold temperature of 100 ° C. and two-point gates from both ends using a FANUC injection molding machine (α-100iA) 3 mm) was measured and measured according to ASTM D790 with respect to the weld part formed in the center part. The bending elastic modulus of the weld part is a measure that indicates the degree of deflection with respect to the stress of the weld part in particular, but if the bending elastic modulus of the weld part is not sufficiently high, it is repeatedly used when put into practical use as a molded product. Depending on the stress load, the weld part may break, and it is desired that the bending elastic modulus of the weld part is sufficiently high as well as an appearance problem. Here, the ratio of b) flexural modulus and g) flexural modulus of the weld portion was taken as the flexural modulus ratio according to the following formula.
Flexural modulus ratio = (flexural modulus of weld) / (flexural modulus)
The flexural modulus ratio is preferably 0.6% or more, and more preferably 0.65 or more.

i) Warpage Using a FANUC injection molding machine (α-100iA), a 1.6mmt, φ100mm disk-shaped test piece was molded at a resin temperature of 280 ° C and a mold temperature of 100 ° C, and the test piece was placed on a horizontal plate. The following four points were measured using an AE100 three-dimensional measuring machine manufactured by Mitoyo Seisakusho, and the amount of warpage was measured by the following equation. The amount of warpage was measured for a sample stored in an aluminum bag for 24 hours or more (absolutely dry state) and a sample immersed in water at 40 ° C. for 24 hours (hygroscopic state) so as not to touch air as much as possible after molding.
Reference points a and b: Two points that are in contact with the horizontal board Warping points c and d: Two points with large warpage Warpage amount calculation formula Warpage amount (mm) = | (c + d) / 2− (a + b) / 2 |

j) Specific surface area of glass fiber Using a fully automatic gas adsorption device, 0.2 g of glass fiber bundle was set, and then adsorption and desorption curves were measured at a relative pressure of 0 to 1 using nitrogen gas. From this measurement result, the specific surface area of the glass fiber bundle was measured by BET multipoint analysis.

Example 1
The crystalline polyamide resin (a1-1) is 55.3 parts by mass, the amorphous polyamide (a2-1) is 23.7 parts by mass, the flame retardant (B-1) is 12.6 parts by mass, and the flame retardant (B -2) is set to 280 ° C. at a cylinder set temperature of 280 ° C. using a twin screw extruder (TEM 37 manufactured by Toshiba Machine) so that the glass fiber (C-1) becomes 100 parts by mass with respect to a total of 100 parts by mass of 8.4 parts by mass. , Under the conditions of a screw rotation of 200 rpm and a discharge rate of 35 kg / h, other than glass fibers are introduced from the base, the glass fibers are side-feeded and kneaded, taken out into a strand shape, cooled and granulated with a cutter, and a polyamide resin composition Product pellets were obtained. Various characteristics of the obtained pellets were examined by the measurement method described above. The results are shown in Table 2.

Examples 1-16
The blending ratio of each component is shown in Table 2, and pellets were obtained in the same manner as in Example I-1 except that the cylinder temperature of the twin screw extruder of Examples 3, 10, and 14 was changed to 260 ° C. I investigated. The results are shown in Table 2.

Comparative Examples 1-12
The blending ratio of each component is shown in Table 3, pellets were obtained in the same manner as in Example 1, and various characteristics were examined. The results are shown in Table 3.

  Since Examples 1 to 16 satisfy the requirements of the present invention, the operability such as clogging of gas vents and retention stability is improved, and the mold release properties, mechanical properties, flame retardancy, surface roughness, and warpage suppression are reduced. A flame retardant polyamide resin composition having excellent effects was obtained.

  Since Comparative Examples 1-4 used the glass fiber other than this invention, they were inferior to the curvature characteristic.

  Comparative Example 5 was inferior in surface roughness because no amorphous polyamide was added.

  In Comparative Example 6, since the proportion of amorphous polyamide is large, the strand cannot be cooled quickly, the take-up is difficult and the operability is poor, and the curing in the mold during the injection molding is completed in a short cycle. It was inferior in releasability.

  Since the comparative example 7 did not add the condensate of phosphoric acid and melamine, it was inferior to a flame retardance.

  Since the flame retardant cyanuric acid melamine other than this invention was used for the comparative example 8, it was inferior to a flame retardance.

  In Comparative Example 9, the flame retardant performance was low because the amount of flame retardant added was small (that means that the amount of polyamide resin was large at the same time).

  In Comparative Example 10, the amount of the flame retardant added was large (that means that the amount of the polyamide resin was small at the same time), so that the strands could not be taken out during the kneading, and the resin pellets could not be collected.

  In Comparative Example 11, the amount of flat glass fiber added was small and the flexural modulus was low.

  In Comparative Example 12, the amount of the flat glass fiber added was too large, and the strands could not be taken out during kneading, and the resin pellets could not be collected.

It is a perspective view of the molded product in evaluation of the curvature amount of this invention.

a, b, c, d: measurement site

Claims (4)

Polyamide resin (A) 60-90% by mass, flame retardant containing no halogen element (B) 40-10% by mass in total 100 parts by mass, and BET specific surface area of 0.1 mm ² / g or more, major axis / minor axis Is a flame retardant polyamide resin composition comprising 60 to 210 parts by weight of flat glass fiber (C) having a ratio of 1.5 to 10, wherein the polyamide resin (A) is amorphous with the crystalline polyamide resin (a1) The mass ratio of the amorphous polyamide resin (a2) in the polyamide resin (A) is 0.1 ≦ (a2) / (A) ≦ 0.5, and the halogen element is A flame retardant polyamide resin composition characterized in that the flame retardant (B) not contained comprises a phosphinate (b1) and / or a diphosphinate (b2) and a reaction product (b3) of phosphoric acid and melamine. .   The blending ratio of the flame retardant (B) containing no halogen element is 10% by mass or more and less than 20% by mass with respect to (A) + (B), and the amorphous polyamide resin (a2 in the polyamide resin (A)) ) Mass ratio of 0.4 ≦ (a2) / (A) ≦ 0.5, The flame retardant polyamide resin composition according to claim 1, wherein:   Furthermore, (D) phosphorus antioxidant or / and (E) hindered phenol antioxidant are contained 0.1-1 mass part in total with respect to a total of 100 mass parts of (A) + (B). The flame-retardant polyamide resin composition according to any one of claims 1 to 3. The flame retardant polyamide according to any one of claims 1 to 5, wherein the phosphinate (b1) is represented by the following general formula (I) and the diphosphinate (b2) is represented by the following general formula (II). Resin composition.
(Wherein R ₁ , R ₄ and R ₂ , R ₅ each represent a linear or branched C _{1 to} C ₁₆ alkyl, and R ₁ and R ₂ and R ₄ and R ₅ form a ring with each other; R ₃ represents linear or branched C _{1 to} C ₁₀ alkylene; M represents calcium or aluminum ion; m is 2 or 3; n is 1 or 3; x is 1 or 2; mx = 2n in formula (II)).