JP2001064521A - Flame retardant resin composition - Google Patents

Abstract

(57) [Problem] To provide a resin composition having excellent flame retardancy. SOLUTION: The flame-retardant resin composition contains a nitrilotris (methylene) phosphonic acid melamine salt represented by the following general formula (1) having an average particle diameter of 20 μm or less. Further, it preferably contains a hydrated metal oxide. Embedded image (In the formula, M represents melamine, and n represents an integer of 2 to 5.)

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant resin composition containing a low-smoke non-halogen flame-retardant, which can impart excellent flame retardancy to various resins. About things.

[0002]

2. Description of the Related Art Conventionally, halides such as chlorine and bromine, phosphorus compounds, nitrogen compounds, or antimony and boron inorganic compounds have been used as flame retardants for plastics.

[0003] However, in recent years, the level of flame retardancy has become severe in all fields, and high flame retardancy has been demanded. In addition, flame retardants containing bromine and chlorine are dioxins which are toxic to the human body in trace amounts during combustion. It has been pointed out that there is a possibility of occurrence of flammability, and demands for non-halogen flame retardants are increasing.

Examples of the non-halogen flame retardant include a resin composition in which red phosphorus is blended with a curable resin (Japanese Patent Publication No. 59-49942), and hydrated alumina as an epoxy resin flame retardant (Japanese Patent Laid-Open No. No. 25369), surface-treated red phosphorus, hydrated alumina, silica powder (JP-A-58-198521), modified red phosphorus (JP-A-63-156860), and a phenol resin. Calcium oxide and aluminum hydroxide or magnesium hydroxide (JP-A-05-43774), boric acid and antimony trioxide (JP-A-60-81244) for phenolic resin, and intramolecular for polyurethane resin. A compound having three triazine structures (JP-A-53-21241) and the like have been proposed.

On the other hand, for a thermoplastic resin, magnesium hydroxide (Japanese Patent Application Laid-Open No. 54-83) is used for a polyamide resin.
952 and JP-A-54-131645),
And melamine cyanurate (JP-A-53-31759, JP-A-54-91558) and organic sulfonates for polycarbonate (JP-A-50-9853).
No. 9, JP-A-50-98540), sulfide salts (JP-B No. 01-22304), phosphonate compounds and polyphosphates for polyphenylene oxide (JP-A-52-86449), phosphate compounds. Antimony trioxide (JP-A-49-3294)
No. 7) and flame retardants such as polyphosphonates (US Pat. No. 3,719,727) for polyesters have been proposed.

However, among the above flame retardants, red phosphorus is reddish brown, so that the resin is colored by the red phosphorus and coloring is impossible. In addition, the working environment is deteriorated due to the generation of phosphine gas during thermal processing or incineration of the resin, and red phosphorus is coated with a coating agent to suppress this, but the generation of phosphine gas is completely prevented. Cannot be suppressed.

[0007]

SUMMARY OF THE INVENTION Organophosphorus flame retardants have received particular attention as non-halogen flame retardants. The flame-retardant mechanism has a high volatility, and the phosphorus compound vaporized by heating acts as an inhibitor of combustion in the gas phase as a diluent for oxygen gas, a cooling effect for the combustion system due to volatilization, and an effect for suppressing the chemical reaction of combustion. By such means, the combustion of plastic is suppressed. On the other hand, those with low volatility generate thermal decomposition by heating to generate phosphoric acid, which becomes metaphosphoric acid and polymetaphosphoric acid, and forms a non-volatile phosphate polymer on the solid phase or molten layer surface of the plastic to be fired. . Also,
The plastic is carbonized by a dehydration reaction of phosphoric acid to form a carbonized layer, whereby the intrusion of air is blocked, and the supply of heat energy from the outside is blocked to suppress combustion.

At present, various types of organophosphorus flame retardants have been proposed, such as phosphoric acid esters and phosphites. However, most of them have low affinity for resins due to their water solubility and low P content in the compounds. Therefore, in order to enhance the flame-retardant effect, a large amount must be contained in the resin, and the mechanical properties are impaired.

[0009] Nitrilotris (methylene) phosphonic acid and its derivatives are used in various fields as scale inhibitors, anticorrosives, metal surface treatment agents and chelating agents, and Japanese Patent Application Laid-Open No. 05-4997 discloses that nitrilotris. It is disclosed that 6 melamine salts of (methylene) phosphonic acid are excellent flame retardant compounds. However, with respect to polyphenylene oxide resin (PPO), UL94H
Although it barely passes the B-level flame retardancy test, it has not yet reached a practical flame retardancy level, and has little flame-retardant effect on other resins.

In view of the above problems, the present inventors have conducted intensive studies on non-halogen flame retardants, and as a result, focused on nitrile tris (methylene) phosphonic acid having a high P content. An application was made for a melamine salt of nitrilotris (methylene) phosphonic acid capable of imparting excellent flame retardancy (Japanese Patent Application No. 10-251779).

Further, such nitrilotris (methylene)
After intensive studies on the melamine salts of phosphonic acids, they have found that those having a particle size in a specific range have good dispersibility in resins and further enhance the flame retardant effect, and have completed the present invention. That is, an object of the present invention is to provide a resin composition having excellent flame retardancy.

[0012]

Means for Solving the Problems The flame-retardant resin composition to be provided by the present invention has the following general formula (1) having an average particle diameter of 20 μm or less.

[0013]

Embedded image

(Wherein, M represents melamine, and n represents 2 to 5)
Represents an integer. ), Which is characterized by containing a melamine salt of nitrilotris (methylene) phosphonic acid represented by the following formula:

It is preferable that the flame-retardant resin composition contains a melamine nitrilotris (methylene) phosphonate represented by the above general formula (1) and a hydrated metal compound.

[0016]

BEST MODE FOR CARRYING OUT THE INVENTION Hereinafter, the present invention will be described in detail.
The flame-retardant resin composition of the present invention contains a melamine nitrilotris (methylene) phosphonate represented by the following general formula (1) having an average particle diameter of 20 μm or less as an active ingredient.

[0017]

Embedded image

In the formula of the nitrilotris (methylene) phosphonic acid melamine salt represented by the general formula (1), n is 2
-5, preferably n is 3-4.

The method for producing the melamine salt of nitrilotris (methylene) phosphonic acid is not particularly limited.
A known method can be used. For example, the following general formula (2)

[0020]

Embedded image

Nitrilotris (methylene) phosphonic acid and melamine represented by the following formula: water, a mixed solvent of water-acetone,
The reaction may be performed at a temperature of 80 ° C. or more in an aqueous solvent such as water-alcohol.

In the above reaction for obtaining the target melamine salt of nitrilotris (methylene) phosphonic acid, the compounding ratio of the starting materials nitrilotris (methylene) phosphonic acid represented by the general formula (2) to melamine is usually The amount of melamine is 2 to 5 mol per mol of the phosphonic acid of the general formula (2), and the amount of melamine introduced into the target substance within the range, for example, the amount of melamine of 2 to 5 melamine, The amount used may be adjusted as appropriate. After the reaction,
Filtration and drying are performed, and pulverization is performed until a product having a desired particle size is obtained to obtain a product.

Specific examples of the nitrilotris (methylene) phosphonic acid melamine salt represented by the general formula (1) include: nitrilotris (methylene) phosphonic acid / 5 melamine salt nitrilotris (methylene) phosphonic acid / 4 melamine salt nitrilotris (Methylene) phosphonic acid / 3 melamine salt Nitrilotris (methylene) phosphonic acid / 2 melamine salt and the like. The above-mentioned melamine salt of nitrilotris (methylene) phosphonic acid is used alone or in combination of two or more.

In the present invention, the melamine nitrilotris (methylene) phosphonate has an average particle size of 2%.
An important requirement is to use one having a range of 0 μm or less. The reason for this is that if the average particle diameter is larger than 20 μm, the dispersibility in the resin becomes poor, and it tends to be impossible to impart stable flame retardancy to the resin molded product.
If the particle size is smaller, it is not practical due to the problem of the pulverizing device or the like.

The average particle size is a value determined by a laser scattering type particle size measuring device (Microtrack).

The compounding ratio of the above-mentioned melamine nitrilotris (methylene) phosphonate to various resins is 0.5 to 30 parts by weight, preferably 1 to 10 parts by weight, based on 100 parts by weight of the resin. . The reason is that if the mixing ratio is less than 0.5 part by weight, it is difficult to obtain a sufficient flame retardant effect, while if it is more than 30 parts by weight, the flame retardant effect becomes large, but the mechanical properties of the molded product deteriorate. It is not preferable because there is a tendency.

The resin that can be used in the present invention is not particularly limited. For example, epoxy resin, phenol resin, polyurethane resin, melamine resin, urea resin, aniline resin, furan resin, alkyd resin, xylene resin, unsaturated resin Curable resin such as polyester resin and diaryl phthalate resin, polybutylene terephthalate resin, polyethylene terephthalate resin, polycarbonate, polyphenylene oxide, polyphenylene ether, nylon 6, nylon 66, nylon 12, polyacetal, polyethylene, polypropylene, polybutadiene, polyacrylonitrile, polystyrene , Polymethyl methacrylate, polyethylene oxide, polytetramethylene oxide, thermoplastic polyurethane, phenoxy resin, polyamide, ethylene On / propylene copolymer, ethylene / 1-butene copolymer, ethylene / propylene /
Non-conjugated diene copolymer, ethylene / ethyl acrylate copolymer, ethylene / glycidyl methacrylate copolymer,
Thermoplastic resins such as ethylene / vinyl acetate / glycidyl methacrylate copolymer, ethylene / propylene-g-maleic anhydride copolymer, polyester polyether elastomer, polytetrafluoroethylene, and modified products thereof are exemplified. These resins may be homopolymers or copolymers, or may be a mixture of two or more.

Here, the curable resin is a resin having a three-dimensional network structure with an increased molecular weight due to a chemical change caused by the action of heat, a catalyst, ultraviolet rays, or the like. This shows a synthetic resin that becomes semi-permanently insoluble and infusible. In addition, the thermoplastic resin indicates a resin that exhibits fluidity by heating and can be shaped thereby.

In the flame-retardant resin composition of the present invention, the flame-retardant effect can be further enhanced by using it in combination with a hydrated metal compound. The hydrated metal compound, the _{M m O n · XH 2 O} (M with a burn suppressing action by endothermic reaction shown metals, m, n is an integer of 1 or more determined by the valency of the metal, X a is-containing crystal water Or a double salt containing the compound, specifically, calcium hydroxide, magnesium hydroxide, basic magnesium carbonate, calcium hydroxide, barium hydroxide, zirconium hydroxide, dawsonite, stannic acid Zinc, zinc borate, aluminum borate, antimony pentoxide, basic zinc carbonate,
Cobalt oxide, zirconium oxide, tin oxide, aluminum oxide, titanium oxide, magnesium oxide, calcium silicate, borax, zinc molybdate, zinc phosphate, magnesium phosphate, hydrotalcite, hydrocalumite, kaolin, talc, sericite , Pyrophyllite, bentonite, kaolinite, calcium sulfate, zinc sulfate and the like. These hydrated metal compounds may be surface-treated, and the average particle size of these hydrated metal compounds is usually 20 μm or less, preferably 1 to 10 μm.

The mixing ratio of the hydrated metal compound is 100
1 to 200 parts by weight, preferably 1 part by weight,
0 to 100 parts by weight.

Further, in the flame-retardant resin composition of the present invention, a flame-retardant auxiliary can be used in combination. Examples of the flame retardant aid include metal oxides such as antimony trioxide, copper oxide, magnesium oxide, zinc oxide, molybdenum oxide, iron oxide, manganese oxide, aluminum oxide, tin oxide, titanium oxide, nickel oxide, and calcium carbonate. , Carbonates such as barium carbonate, zinc metaborate, metaborates such as barium metaborate, melamine, melamine cyanurate,
Methylolated melamine, (iso) cyanuric acid, melam, melem, melon, succinogamine, melamine sulfate, acetoguanamine sulfate, melam sulfate, guanylmelamine sulfate, melamine resin, BT resin, cyanuric acid,
Isocyanic acid, isocyanuric acid derivatives, melamine isocyanurate, benzoguanamine, melamine derivatives such as acetoguanamine, guanidine compounds, silicone compounds, one or more selected from phosphorus-based flame retardants, and the like. Among them, phosphorus-based flame retardants are particularly preferred.

Examples of the phosphorus-based flame retardant include triethyl phosphate, tricresyl phosphate, triphenyl phosphate,
Cresyl phenyl phosphate, octyl diphenyl phosphate,
Ethyl diethylene phosphate, butyl dihydroxypropylene phosphate, disodium ethylene phosphate, methylphosphonic acid, dimethyl methylphosphonate, diethyl methylphosphonate, ethylphosphonic acid,
Propylphosphonic acid, butylphosphonic acid, 2-methyl-
Propylphosphonic acid, t-butylphosphonic acid, 2,3-
Dimethylbutylphosphonic acid, octylphosphonic acid, phenylphosphonic acid, dioctylphenylphosphonate, dimethylphosphinic acid, methylethylphosphinic acid, methylpropylphosphinic acid, diethylphosphinic acid, dioctylphosphinic acid, phenylphosphinic acid, diethylphenylphosphinic acid, diphenylphosphine Acid, bis (4-methoxyphenyl) phosphinic acid, red phosphorus, ammonium phosphate, ammonium polyphosphate, melamine phosphate, guanylurea phosphate, melamine polyphosphate, guanidine phosphate, ethylenediamine phosphate, phosphazene, melamine methylphosphonate One or more selected from salts are mentioned. Among these, red phosphorus, ammonium phosphate, ammonium polyphosphate, melamine phosphate,
Guanylurea phosphate, melamine polyphosphate, and guanidine phosphate are preferably used.

Red phosphorus whose surface is modified by an organic substance and / or an inorganic substance is preferable. For example, phenol resin, epoxy resin, ethylene-vinyl acetate copolymer, melamine-formaldehyde polycondensate, Mg, Ca, Ti , A
Examples thereof include, but are not limited to, hydroxides of l, Co, and Zr and those surface-treated with one or more selected from these oxides.

The mixing ratio of these flame retardant aids is 100
It is usually 0.1 to 10 parts by weight, preferably 0.5 to 5 parts by weight with respect to parts by weight.

Other components to be added to the resin include phosphorus-based, ionic-based, hindered-phenol-based antioxidants, heat stabilizers, ultraviolet absorbers, lubricants, releasing agents, coloring agents including dyes and pigments. , A cross-linking agent, a softening agent, a dispersant and the like.

If necessary, fibrous and / or granular fillers can be added to significantly improve the rigidity of the resin. As such a filler, for example, glass fiber, carbon fiber, metal fiber, aramid resin,
Asbestos, potassium titanate whisker, walastenite, glass flake, glass beads, talc, mica,
Examples include clay, calcium carbonate, calcium silicate, barium sulfate, titanium oxide, fused silica, crystalline silica, magnesia, and aluminum oxide.

In the present invention, the flame retardant comprising the nitrilotris (methylene) phosphonic acid melamine salt represented by the general formula (1) and, if necessary, other additives as described above is generally prepared by a known method. It can be contained in various resins. For example, in the case of a curable resin, a method in which a flame retardant is mixed with the curable resin and other components simultaneously, and a method in which a flame retardant is mixed in advance with one of the resin components and then mixed with the curable resin In the case of a thermoplastic resin, a method in which a flame retardant is melt-mixed with an extruder, a method in which particles are uniformly and mechanically mixed with each other, and a method in which the particles are mixed with an injection molding machine at the same time as molding are used.

The flame-retardant resin composition of the present invention can be sufficiently applied as safe plastic materials to the fields of electric parts, building materials, transportation equipment such as automobiles, packaging materials, household daily necessities and the like.

[0039]

The present invention will be described below in more detail with reference to examples, but the present invention is not limited to these examples.

Synthesis Example 1 <Preparation of Melamine Salt of Nitrilotris (methylene) phosphonic Acid> Sample A: Nitrilotris (methylene) phosphonic acid.2.
Melamine 18L stainless steel container, 10L of tap water, nitrilotris (methylene) phosphonic acid (hereinafter abbreviated as NTP)
(50% aqueous solution) 1802.0 g (3.00 mol) was added and stirred. After the temperature was raised to 80 ° C., melamine 7 was added.
62.0 g (6.00 mol) was gradually added and stirred.
After the addition of melamine, the pH of the reaction solution is constant (about 1.
Stirring was continued at 80 ° C. until 5). Thereafter, centrifugal filtration was performed to obtain white crystals. The crystals were dried at 100 ° C. for 24 hours to obtain 1494.5 g of the desired product. Yield 9
0.3% (yield based on NTP).

Next, the obtained crystals were pulverized with a mixer to prepare nitrilotris (methylene) phosphonic acid / 2-melamine having various average particle sizes shown in Table 1 below. The average particle size was determined by laser scattering particle size measurement (Microtrack). By elemental analysis, C,
As a result of measuring H and N, C: 19.79%, H: 4.3
8%, N: 32.02%.

Sample B: nitrilotris (methylene) ho
Suhon acid 3 Melamine 18L stainless steel container of tap water 15L, NTP (50
% Aqueous solution) and stirred. After the temperature was raised to 80 ° C., melamine 114 was added.
0.0 g (9.03 mol) was gradually added and stirred. After addition of melamine, the pH of the reaction solution is constant (about 1.5)
Stirring was continued at 80 ° C. until. Thereafter, centrifugal filtration was performed to obtain white crystals. The crystals are grown at 100 ° C for 24 hours.
After drying for 1 hour, 1909.66 g of the target product was obtained. Yield 9
3.9% (Yield based on NTP).

Then, the obtained crystals were pulverized by a mixer to prepare nitrilotris (methylene) phosphonic acid / 3 melamine having various average particle sizes shown in Table 1 below. The average particle size was determined by laser scattering particle size measurement (Microtrack). By elemental analysis, C,
As a result of measuring H and N, C: 20.84%, H: 4.4
1%, N; 38.49%.

Sample C: nitrilotris (methylene) ho
Sulfonic acid / 4 melamine 18L Stainless steel container 15L tap water, NTP (50
897.0 g (1.49 mol) was added and stirred. After the temperature was raised to 80 ° C., melamine 751.6 was used.
g (5.96 mol) was gradually added and stirred. After completion of the melamine addition, stirring was continued at 80 ° C. until the pH of the reaction solution became constant (about 4.2). Thereafter, centrifugal filtration was performed to obtain white crystals. The crystals were dried at 100 ° C. for 24 hours to obtain 1144.06 g of the desired product. 95.2% yield
(Yield based on NTP).

Next, the obtained crystals were pulverized with a mixer to prepare nitrilotris (methylene) phosphonic acid / 4 melamine having various average particle sizes shown in Table 1 below. The average particle size was determined by laser scattering particle size measurement (Microtrack). By elemental analysis, C,
As a result of measuring H and N, C: 21.52%, H: 4.4
1%, N; 41.82%.

Sample D: nitrilotris (methylene) ho
Sulfonic acid / 5 melamine 18L Stainless steel container in tap water 15L, NTP (50
897.0 g (1.5 mol) was added and stirred. After the temperature was raised to 80 ° C., 945.9 g of melamine was used.
(7.5 mol) was gradually added thereto, followed by stirring. After completion of the melamine addition, stirring was continued at 80 ° C. until the pH of the reaction solution became constant (about 4.3). After that, perform centrifugal filtration,
White crystals were obtained. The crystals were dried at 100 ° C. for 24 hours to obtain 785.4 g of the desired product. Yield 84.5% (NT
Yield based on P).

Next, the obtained crystals were pulverized with a mixer to prepare nitrilotris (methylene) phosphonic acid / 5 melamine having various average particle sizes shown in Table 1 below. The average particle size was determined by laser scattering particle size measurement (Microtrack). By elemental analysis, C,
As a result of measuring H and N, C: 22.9%, H: 4.1.
%, N; 46.1%.

[0048]

[Table 1]

(Note 1) The average particle diameter is a value determined by a laser scattering particle size analyzer (Microtrack).

Examples 1 to 8 and Comparative Examples 1 to 4 Various additives were added to ethyl ethylene acrylate (hereinafter abbreviated as EEA) resin at the compounding ratios shown in Tables 2 to 3, and 120 to 130 The mixture was kneaded for 5 to 10 minutes with a hot roll set at ℃.

The molding pressure was 150 kg /
cm ² , pressurization time 5 minutes, mold temperature 115 ° C, thickness 3
mm sheet, length 125 mm, width 13
mm test pieces were prepared, and the resin was tested for flame retardancy and surface properties. In addition, Kisuma 5A manufactured by Kyowa Chemical Co., Ltd. was used as magnesium hydroxide.

<Flame Retardancy Test> The flame retardancy test is a vertical flame test (94) of a material obtained by classifying a resin processed into a length of 125 mm × a width of 13 mm × a thickness of 3 mm adjusted as described above into UL94.
V-0, 94V-1 and 94V-2). The results are shown in Tables 5 and 6. In addition, UL9
Table 4 shows the conditions for the availability of 4.

[0053]

[Table 2]

[0054]

[Table 3]

[0055]

[Table 4]

[0056]

[Table 5]

[0057]

[Table 6]

(Note 1) Surface properties were measured by touch. (Note 2) The residual flame time after flame contact in Tables 5 and 6 corresponds to Test 2 in Table 4. For the second residual flame time, the same test piece used in the first test was used as it was. It is the after-flame time after the flame contact tested.

From the results shown in Tables 5 and 6, the particle size of the melamine phosphonic acid salt was reduced to improve the dispersibility of the resin in the resin. It is recognized that flame retardancy can be imparted to the resin.

Examples 9 to 16 and Comparative Examples 5 to 8 Novolak resins prepared at a molar ratio of formaldehyde / phenol = 0.9 were mixed with various additives at the mixing ratios shown in Tables 7 to 8. Then, the mixture was kneaded with a hot roll set at 80 to 90 ° C. for 5 minutes. After crushing, using a universal press, forming pressure 250 kg / cm ² , pressing time 60 seconds,
A molded product having a predetermined shape was prepared at a mold temperature of 150 ° C.

The flame retardancy test was evaluated by the same operation method as in Examples 1 to 8. The results are shown in Tables 9 and 10.

[0062]

[Table 7]

[0063]

[Table 8]

[0064]

[Table 9]

[0065]

[Table 10]

Examples 17 to 24 and Comparative Examples 9 to 12 Various additives shown in Table 11 were added to various resins.
ASTM D- by injection molding using a mmΦ screw extruder
A tensile test specimen specified in 638 was prepared, and strength and elongation were measured based on the test method of JIS K7113.

Similarly, a test piece for evaluating flame retardancy based on UL94 was prepared, and the flammability was evaluated. Table 12 shows the results.
Shown in The conditions of melt extrusion, pellet drying, and injection molding for each resin are shown below.

Polybutylene terephthalate (hereinafter referred to as P
Extrusion; 250-290 ° C / 150 rpm drying; 110 ° C / 12 hours molding; 250-290 ° C / die 80 ° C ・ Nylon 6 extrusion; 250-300 ° C / 150 rpm drying; 100 ° C / 24 hours molding 250-300 ° C / die 80 ° C ・ Polycarbonate extrusion; 260-320 ° C / 75 rpm drying; 120 ° C / 12 hours molding; 260-320 ° C / die 110 ° C ・ A mixture of polyphenylene oxide and polystyrene (mixing weight ratio; 60:40; hereinafter abbreviated as PPO) Extrusion; 240-310 ° C / 70 rpm Drying; 110 ° C / 4 hours Molding; 240-320 ° C / die 90 ° C

[0069]

[Table 11]

[0070]

[Table 12]

Examples 25 to 28 and Comparative Example 13 A polypropylene resin (hereinafter abbreviated as PP) was added to Table 1
Various additives were added at the mixing ratios shown in FIG.
The mixture was kneaded for 5 minutes with a hot roll set at ℃. Melt extrusion was performed at a screw rotation speed of 87 rpm. UL94 by injection molding (cylinder temperature: 230 ° C, mold temperature 50 ° C)
The test piece based on was prepared.

The red phosphorus whose surface was modified with aluminum hydroxide and titanium hydroxide was used. Table 13 shows the results of the flame retardancy test.

[0073]

[Table 13]

[0074]

As described above, the flame-retardant resin composition of the present invention uses a non-halogen flame retardant having excellent resin dispersibility. It has the effect of imparting flammability.

──────────────────────────────────────────────────の Continued on the front page (51) Int.Cl. ⁷ Identification symbol FI Theme court ゛ (Reference) C08K 5/5317 C08K 5/5317 (72) Inventor Nobuo Matsumoto 9-11-1, Kameido, Koto-ku, Tokyo Japan Chemical Chemical Co., Ltd. F-term (Reference) 4J002 AC031 BB031 BB041 BB051 BB061 BB071 BB121 BB151 BB211 BC031 BD151 BF021 BF031 BF051 BG061 BG101 CB001 CC031 CC121 CC151 CC161 CC181 CC182 CD1 CD191 CF01 CF01 CF06 CL031 DA058 DE077 DE078 DE087 DE097 DE098 DE108 DE127 DE128 DE137 DE138 DE147 DE148 DE187 DE238 DE267 DE277 DE287 DG047 DG057 DH047 DH048 DH058 DJ007 DJ037 DJ047 DK007 DK008 ER028 EU188 EU198 EV188 EV348 FD 138 138 EW 138 FD 138

Claims (5)

[Claims] 1. The following general formula (1) having an average particle size of 20 μm or less. (Wherein, M represents melamine, and n represents an integer of 2 to 5). A flame-retardant resin composition comprising a melamine salt of nitrilotris (methylene) phosphonic acid represented by the formula: 2. The flame-retardant resin composition according to claim 1, comprising the melamine salt of nitrilotris (methylene) phosphonic acid according to claim 1 and a hydrated metal compound. 3. The flame retardant resin composition according to claim 2, further comprising a flame retardant auxiliary. 4. The flame-retardant resin composition according to claim 3, wherein the flame-retardant auxiliary is a phosphorus-based flame retardant. 5. The phosphorus-based flame retardant is at least one selected from red phosphorus, ammonium phosphate, ammonium polyphosphate, melamine phosphate, guanylurea phosphate, melamine polyphosphate and guanidine phosphate. 4
The flame-retardant resin composition according to the above.