JPH07187626A - Coated ammonium polyphosphate - Google Patents

Abstract

PURPOSE:To reduce the water solubility of ammonium polyphosphate particles as a defect of the flame retardant and to further improve the flame retarding performance by coating the ammonium polyphosphate particles. CONSTITUTION:Ammonium polyphosphate particles each having 0.1-100mum particle diameter are coated with a vinyl copolymer having functional groups cross-linkable with a polyamine compd. to obtain the objective coated ammonium polyphosphate. When a compd. contg. a triazine ring or polyol is incorporated into the coated ammonium polyphosphate, a flame retardant compsn. is obtd.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a modified ammonium polyphosphate used as a flame retardant, and more specifically, it reduces the water solubility, which is a drawback of the flame retardant, and at the same time exerts its flame retarding effect. It relates to improved ammonium polyphosphate.

[0002]

2. Description of the Related Art Conventionally, a large amount of halogen-based flame retardants have been used for flame-retarding thermoplastic molding resins, especially polyolefin resins and styrene resins. However, recently, the problems of environmental pollution and destruction of halogen compounds have been highlighted, and various regulations have been made regarding their use. Such movements extend to halogen-based flame retardants used for flame retarding resins, and the production and use of halogen-based flame retardants may be regulated, or the user may voluntarily regulate without regulations. There is a marked movement to stop using specific halogen-based flame retardants and switch to other flame retardants that are considered safe. Furthermore, halogen-based flame retardants are also considered to generate a large amount of corrosive gas and black smoke during a fire or incineration process.Therefore, a safer flame retardant or flame-retardant system alternative to halogen-based flame retardants Development is urgent.

Studies have been actively conducted to replace the halogen-based flame retardant used in these resins with a non-halogen-based flame retardant, and some have reached the stage of practical application. As one of them, a phosphorus-based flame retardant, in particular, a flame retardant composition containing ammonium polyphosphate as a main component has been studied.

However, ammonium polyphosphate has a high hygroscopic property, has a high water solubility under high temperature and high humidity conditions, and when mixed with a resin and used, bleeding out occurs on the surface of the molded product during use. Occurs. Furthermore, the flame retardant containing ammonium polyphosphate as a main component has no affinity for the above-mentioned thermoplastic resins, and the mechanical properties of the resin composition, the appearance, etc. are markedly similar to the case where these resins are filled with an inorganic filler. It also has a problem that damages it. Various means for solving the problems of these ammonium polyphosphates have been studied, but most of them are carried out by coating ammonium polyphosphate particles with a thermosetting resin.

That is, in US Pat. No. 4,639,331, ammonium polyphosphate coated with melamine / formaldehyde resin or phenol / formaldehyde resin, DE
3,526,006 ammonium polyphosphate coated with polyisocyanurate carbodiimide, DE3.
526,965, ammonium polyphosphate coated with polyurethane resin, EP180790, ammonium polyphosphate coated with polyurea, JP-A-3-131.
At 508, a silicone resin coated ammonium polyphosphate is disclosed.

The ammonium polyphosphate particles coated with the thermosetting resin disclosed in these prior arts have reduced water solubility, which is a drawback of ammonium polyphosphate, and also have a problem of bleed-out when made into a resin composition. Has been improved. Further, many of the problems that must be solved in order to put ammonium polyphosphate into practical use as a flame retardant for resins have been improved, such as the hue of a resin composition being improved.

However, any of the thermosetting resins used for coating ammonium polyphosphate in these prior arts has a poor affinity for polyolefin-based resins and styrene-based resins, and therefore these thermosetting resins are used for coating. When the above-mentioned ammonium polyphosphate is added to a flame-retardant resin in an amount sufficient to ensure flame retardancy, the mechanical properties of the resin composition are significantly impaired.

[0008]

The object of the present invention is to solve or improve such problems associated with the use of a flame retardant containing ammonium polyphosphate as a main component, enhance the effect of the flame retardant, and increase the amount of the flame retardant used. An object is to provide an improved ammonium polyphosphate-based flame retardant that can be reduced.

[0009]

The inventor of the present invention is able to further improve the affinity between ammonium polyphosphate and a flame-retardant resin in order to improve mechanical properties and appearance characteristics of a resin composition using this flame retardant. The present invention has been accomplished as a result of thought that it is necessary to improve the decrease and earnestly studied means for achieving it.

That is, the present invention has a particle size of 0.1 to 10 which is coated with a vinyl copolymer crosslinked with a polyamine compound.
Ammonium polyphosphate having a particle diameter of 0.1 to 100 microns, coated with a vinyl-based copolymer cross-linked with 100 micron ammonium polyphosphate and (a) polyamine compound, (b) triazine ring-containing compound or polyhydric alcohol A flame retardant composition comprising

The present invention will be described in detail below. The vinyl copolymer used in the present invention is required to be crosslinked with a polyamine compound for the following reason. Generally, when ammonium polyphosphate is used as a flame retardant for a polyolefin resin, it may not always be possible to obtain sufficient flame retardancy by itself. Therefore, a triazine ring-containing compound that easily forms a foamed carbon layer (char) during combustion and a polyhydric alcohol represented by pentaerythritol, dipentaerythritol, tripentaerythritol, and the like are used in combination. In this flame-retardant system, the heat-insulating effect of the generated char, oxygen, and the effect of blocking combustible gas impart flame retardancy to the resin.
In the prior art, to make this char more efficient,
We are developing various flame retardants by adding various chemical modifications to triazine ring-containing compounds and polyhydric alcohols.

For example, a salt formed from a phosphoric acid ester having a spiro ring structure obtained by reacting phosphoric acid with pentaerythritol and a triazine compound such as melamine.
Flame retardant described in US Pat. No. 4,154,930, US Pat.
1,3,5-triazine derivative oligomer, which is a flame retardant composition component in US Pat. No. 4,873,984, a polymer of hydroxyalkyl derivative of isocyanuric acid used in US Pat. No. 4,997,876, flame retardant composition in US Pat. No. 5,124,379. Examples are 2,4,6-triamino-1,3,5-triazine derivatives, which are physical components, and each exhibits excellent flame retardancy.

However, using these flame retardants,
In order to impart the flame retardancy of UL94V-0 to the polyolefin resin, 25 to 30 parts by weight of the flame retardant with respect to 100 parts by weight of the polyolefin resin is required to reduce the deterioration of mechanical properties of the resin composition. In addition, it is necessary to further improve the performance of flame retardants and reduce the amount used. Further, these improved flame retardants are obtained through a complicated synthesis process, and are considerably more expensive than halogen-based flame retardants, and flame-retardant resins using these flame-retardants are halogen-based flame-retardants. It is inevitable that the price will be higher than that using a flame retardant, and also from this aspect, it is necessary to improve the performance of the flame retardant and reduce the amount used, or to reduce the cost of the flame retardant.

Therefore, the inventors of the present invention have made earnest studies to solve the problems of the flame retardant containing ammonium polyphosphate as a main component, and as a result, the amine compound in the resin composition using this flame retardant has been investigated. It was found that the performance of the flame retardant is remarkably improved when a small amount of is present. Furthermore, as a result of investigating in what form this amine compound, which has problems such as volatility, odor, bleed-out property and water solubility, in a resin composition, a vinyl-based copolymer crosslinked with a polyamine compound was found. It has been found that ammonium polyphosphate as a flame retardant coated with a polymer is effective for containing an amine compound in a resin composition after solving the above-mentioned problems associated with the amine compound, and thus the present invention was achieved. It was Thus, ammonium polyphosphate coated with a vinyl-based copolymer cross-linked with an amine compound,
Not only the flame retardancy-providing performance is improved by the amine compound, but also the problems of water solubility and affinity with the resin, which are the drawbacks of ammonium polyphosphate, are reduced by the coating, and the polyolefin resin, styrene resin It has excellent performance as a flame retardant for many resins including resins.

As the ammonium polyphosphate, crystalline forms I and II are commercially available. However, since there is no great difference in the flame retardant performance, any of them can be used in the present invention. However, there is a considerable difference between the two in terms of hygroscopicity and water solubility, which are the drawbacks of ammonium polyphosphate, and in this respect, those having a type II crystal form with a large molecular weight are suitable for use. Further, since the flame retardant performance of ammonium polyphosphate largely depends on the surface area (particle diameter) of the particles and the dispersed state in the resin, it is desirable to use ammonium polyphosphate having the smallest particle diameter.

Considering ease of production and handling, ammonium polyphosphate having a particle size of 0.1 to 100 μm is suitable for use, further 1 to 30 μm, and more preferably 2 μm. Ammonium polyphosphate having a particle size of about 10 microns is most suitable.

In the present invention, the vinyl-based copolymer used for coating the ammonium polyphosphate particles is a vinyl-based copolymer having a functional group that easily reacts with an amine compound such as a glycidyl group, an anhydrous carboxyl group and a maleimide group. is there. Such a vinyl-based copolymer is a copolymer of at least one of α-olefin-based vinyl monomers such as ethylene and propylene, aromatic vinyl-based monomers such as styrene and vinyltoluene, and (meth) acrylic acid ester-based monomers with these monomers. A polymerizable glycidyl group-containing monomer such as glycidyl (meth) acrylate, glycidyl ethacrylate, and a carboxyl group-containing monomer such as maleic anhydride are used together with at least one kind of monomer having a functional group that easily reacts with an amine. Obtained by polymerizing. When the copolymerization ratio of these functional group-containing monomers is less than 1% by weight, the amount of the crosslinking of the amine compound and the amount of the amine compound fixed to the coating becomes insufficient to achieve the object of the present invention, and the amount is 50% by weight. If it exceeds%, the amount of the amine compound fixed on the coating becomes too large, and the effect of reducing the hygroscopicity of ammonium polyphosphate becomes small. Therefore, the copolymerization ratio of these functional group-containing monomers is appropriately in the range of 1 to 50% by weight, preferably 3 to 40% by weight.

Further, in the present invention, the vinyl-based copolymer used for coating the ammonium polyphosphate particles includes other unsaturated monomers copolymerizable within a range not impairing the properties thereof, such as vinyl ether, vinyl acetate and vinyl propionate. It is possible to copolymerize vinyl esters such as, and esters of acrylic acid and methacrylic acid such as methyl, ethyl and propyl.

The α-olefin polymer containing ethylene as a main component is prepared by kneading the polymer with glycidyl (meth) acrylate or maleic anhydride in the presence of a peroxide initiator and heating with an extruder or the like. A glycidyl group or an anhydrous carboxyl group can be introduced into an α-olefin polymer, and a polymer produced by such a method is also included in the vinyl-based copolymer according to the present invention.

The molecular weight of these vinyl-based copolymers needs to reach the molecular weight capable of forming a film on the surface of ammonium polyphosphate particles, and usually 1,000 to 1.0.
A material of about 0,000 is suitable for use. The method for coating ammonium polyphosphate with a vinyl-based copolymer is
A known microencapsulation technique can be applied. That is, a vinyl-based copolymer having a functional group that easily reacts with an amine compound such as a glycidyl group or an anhydrous carboxyl group is dissolved in a solvent together with an amine compound containing at least one or more polyamines, and then the polyphosphoric acid is added to the polymer solution. By dispersing the ammonium acid particles, and stirring, the amine compound and the glycidyl group or the maleic anhydride group contained in the vinyl polymer, and the maleimide group are reacted to crosslink the vinyl polymer and introduce the amine compound, Further, ammonium polyphosphate can be coated. Further, during the reaction or after the completion of the reaction, if the solvent is made into a poor solvent by an appropriate method, it is convenient because the coated ammonium polyphosphate particles can be prevented from aggregating with each other.

As another method, the vinyl polymer is dissolved together with an amine compound in a mixed solvent consisting of a good solvent having a low boiling point and a nonsolvent having a high boiling point, ammonium polyphosphate particles are dispersed in this solution, and the boiling point is lowered with stirring. By evaporating and removing the good solvent, a vinyl polymer film can be formed on the ammonium polyphosphate particles, and the amine compound can be introduced into the polymer film as a crosslinked chain or a graft chain.

As another method, when a polymer containing styrene or an acrylic ester as a main component is used as the vinyl polymer, the monomers constituting the polymer are easily reacted with a small amount of a crosslinkable monomer and an amine. By dissolving in a solvent together with a copolymerizable monomer having a functional group to be dispersed, ammonium polyphosphate particles are dispersed in the solvent, and polymerization is carried out in the presence of a suitable polymerization initiator, thereby forming a vinyl-based polymer on the ammonium polyphosphate particles. Can be formed. Further, an amine compound can be reacted with this coating to crosslink the coating and fix the amine compound to the coating.

The amine compounds that can be used in the present invention include monoamines, polyamines, aliphatics, aromatics, etc., as long as they can react with glycidyl groups and anhydrous carboxyl groups, in addition to polyamines used as crosslinking agents. An amine compound can be used in combination. Further, heterocyclic amines such as morpholine, piperidine and its derivatives can be used.

However, since the hydrocarbon group and hydrogen atom contained in the amine compound become a source of combustible gas during combustion, the amine compound used should preferably have a carbon / nitrogen atom ratio as small as possible. Value of 0.5 to 1
A range of 5 is suitable. Furthermore, in order to introduce as much amine as possible into the vinyl-based polymer coated with ammonium polyphosphate, the use of polyamine is preferable. Illustrative amine compounds suitable for use in the present invention are:
Aromatic amines such as methylamine, dimethylamine, ethylamine, diethylamine, ethylenediamine, propylenediamine, diethylenetriamine, triethylenetetramine, tetraethylenepentamine, pentaethylenehexamine, N-substituted derivatives of these amines, aniline, phenylenediamine, and xylylenediamine , Cyclohexylamine, cyclohexenediamine, alicyclic amines such as 2,5- (or 2,6-) bicyclo [2,2,1] heptanebis (methylamine), piperidine, piperazine, and carbon atoms forming the ring Examples include derivatives having a substituent introduced. Further, the amine compound that can be used in the present invention also includes a compound obtained by adding a polyamine such as diethylenetriamine to the glycidyl group of an epoxy resin represented by a nylon oligomer having amines at both ends, ethylene glycol, and diglycidyl ether of propylene glycol.

The optimum range of the amine compound fixed to the vinyl polymer is preferably 10 to 200 parts by weight, more preferably 100 parts by weight of the vinyl polymer.
30 to 100 parts by weight is suitable. If it is less than 10 parts by weight, the amount of the amine compound that can be contained in the resin composition is insufficient to enhance the effect of the flame retardant using ammonium polyphosphate when ammonium polyphosphate of the present invention is used as the flame retardant. However, if the amount exceeds 200 parts by weight, the hydrophobic property of the vinyl polymer is weakened, and the effect of lowering the hygroscopicity of ammonium polyphosphate is lost.

In the vinyl polymer cross-linked with the amine compound in this way, the amino group causes a substitution reaction with a part of the ammonia of ammonium polyphosphate, so that it is firmly adhered to the surface of the ammonium polyphosphate particles and peeled off. Hateful.

The ammonium polyphosphate obtained by coating the vinyl copolymer cross-linked with the polyamine compound thus obtained has the problems of water solubility and hygroscopicity, which are the drawbacks of ammonium polyphosphate, improved. Not only that, but due to the synergistic effect of the amine fixed to the coating film, extremely excellent flame retardant performance is exhibited in the flame retardant composition composed of ammonium polyphosphate, triazine ring-containing compound or polyhydric alcohol.

As an example, when a flame retardant composition comprising ammonium polyphosphate and melamine cyanurate is used to make polypropylene flame-retardant, 100 wt. Even if 35 parts by weight of a flame retardant composition having a composition of ammonium polyphosphate / melamine cyanurate = 100/30 (weight ratio) is used, the UL94V-
Although flame retardancy of 0 is not obtained, when using the coated ammonium polyphosphate of the present invention, when a flame retardant composition having the same composition is used, even if the amount of use is 25 parts by weight, UL94V is sufficient.
Flame retardancy of −0 is obtained. It also exhibits self-extinguishing properties and exhibits excellent flame retardancy.

The coated ammonium polyphosphate of the present invention is a triazine ring compound having a large char-forming ability, such as melamine, ammeline, melamine cyanurate, melam, melem, benzoguanamine, butylene diguanamine, bis (4,6-diamino-). 1,3,5-triazin-2-yl) cyclohexane, methylene dimelamine, tetramethylene dimelamine, hexamethylene dimelamine,
When combined with one or more of 1,3-hexylene dimelamine, p-xylene dimelamine, melamine resin, ethylene urea resin and the like to form a flame retardant composition, the triazine ring derivative starting from cyanuric acid of the prior art is used. Polyamine-linked 1,3,5-triazine derivative oligomer (U.S.P. 4,504,610), tris (2-hydroxyethyl) isocyanurate or its oligomer (U.S.P. 4,727, A flame retardant performance comparable to 102) can be obtained without using an expensive triazine ring derivative having a special structure. The coated ammonium polyphosphate of the present invention is also effective when a polyhydric alcohol such as pentaerythritol, dipentaerythritol, tripentaerythritol or the like is used as a char generation source instead of the triazine ring compound.
When both are combined, an excellent flame retardant composition is obtained as in the case of the above triazine ring compound.

In order to form a flame retardant composition by combining the coated ammonium polyphosphate of the present invention with the triazine ring compound or the polyhydric alcohol, 100 parts by weight of the coated ammonium polyphosphate or the polyazine phosphate is used. A mixing ratio of 10 to 200 parts by weight, and particularly 20 to 100 parts by weight of the polyhydric alcohol shows excellent flame retardant performance. When the ratio of the triazine ring compound or the polyhydric alcohol is less than 10 parts by weight, the amount of char produced is too small and the flame retardant performance does not reach a satisfactory level. On the other hand, when the amount exceeds 200 parts by weight, the flame retardant performance is remarkably deteriorated due to the lack of the phosphorus component.

The flame retardant composition is particularly effective for flame retarding thermoplastic resins, especially polyolefins, and is polypropylene, polyethylene, ethylene / propylene copolymers, ethylene / vinyl acetate copolymers, ethylene / acrylic acid esters. It exhibits excellent flame retardancy as a flame retardant for copolymers and polybutylene. Usually, in order to obtain the flame retardancy of UL94V-0, it is sufficient to use 15 to 40 parts by weight of the flame retardant composition with respect to 100 parts by weight of the resin.

[0032]

【Example】

Coating with Example 1 (styrene / glycidyl methacrylate copolymer) Styrene / glycidyl methacrylate copolymer (AP-
2024 Mitsui Toatsu Chemicals Co., Ltd.) 5 g benzene / isopropyl alcohol mixed solvent (1 vol / 1 vol) 2
Dissolve in 0 ml and add 3 g of pentaethylenehexamine
Was added and the reaction was carried out at 60 ° C. for 6 hours. After the reaction was completed, 80 ml of the above mixed solvent was added, and 30 g of ammonium polyphosphate having an average particle size of 6 μm was dispersed in the solution. When the solvent is removed under stirring, the solvent becomes a poor solvent in the process, and the polymer is deposited on the surface of ammonium polyphosphate. When half of the solvent used (about 50 ml) was removed, another 50 ml of isopropyl alcohol was added and solvent removal was continued. After completely removing the solvent, post-treatment was performed for 2 hours in a nitrogen atmosphere in a drying oven at 100 ° C. As a result, 37 g of coated ammonium polyphosphate was obtained.

Example 2 (Coating with ethylene / glycidyl methacrylate copolymer) 5 g of ethylene / glycidyl methacrylate copolymer (manufactured by Bondyne Sumitomo Chemical Co., Ltd.) was dissolved in 30 ml of xylene under reflux, and the temperature was lowered to 120 ° C. .
To this, 3 g of pentaethylenehexamine was added, and with stirring, 3
The reaction was carried out over time. This reaction solution had an average particle size of 15 μm.
30 g of ammonium polyphosphate from above was added and the temperature was lowered to 60 ° C. with stirring.
ml was added dropwise with stirring at 60 ° C. over 30 minutes.
The temperature was lowered to room temperature and then filtration was performed to obtain a coated ammonium polyphosphate. After drying, the weight was measured and the result was 36.5 g of ammonium polyphosphate coated.
was gotten.

Example 3 (Coating with styrene / maleic anhydride copolymer) 5 g of a styrene / maleic anhydride copolymer (manufactured by Dailark Mitsui Toatsu Chemicals, Inc.) was dissolved in 30 ml of benzene, and 3 g of piperazine was dissolved therein. The reaction was performed at 60 ° C. for 5 hours. 70 ml of a benzene / isopropyl alcohol mixed solvent (2: 1 weight ratio) was added to this reaction solution, and then ammonium polyphosphate (EXOLIT422) having an average particle diameter of 6 μm was added.
30 g of Hoechst) was dispersed. Under stirring,
After removing the solvent and distilling 10 ml, the operation of adding 10 ml of isopropyl alcohol was repeated 5 times, and then the solvent was completely removed using an evaporator. As a result of weighing after drying, 36.5 g of coated ammonium polyphosphate was obtained.

Example 4 (Coating with Maleated Polyolefin) Maleated Polyolefin (Mitsui Law Ply Mitsui Toatsu Chemical Co., Ltd.) 5
g was dissolved in 30 ml of toluene under heating at 110 ° C. 1
After the temperature was lowered to 00 ° C., 3 g of pentaethylenehexamine was added, and the reaction was carried out at 100 ° C. for 4 hours. 70 after reaction
ml of toluene was added to this reaction solution, and then the average particle size was 9
μm ammonium polyphosphate (EXOLIT422)
30 g was dispersed. The above dispersion was cooled to 30 ° C. with stirring, and 100 ml of methanol was added dropwise. The above dispersion was solvent-separated by decantation, further dispersed in methanol, and then ammonium polyphosphate covered by filtration was separated. As a result of weighing after drying, 37.6 g of coated ammonium polyphosphate was obtained.

Examples 5 to 10 Using the coated ammonium polyphosphate obtained in Examples 1 to 4, flame retardant resin compositions shown in Table 1 were prepared and flame retardancy was evaluated. Flame retardant resin composition is polypropylene (Mitsui Noblene BJHH) or Topolex 83
0 / block SBR = 90/10 (HIPS) 100 g
And ammonium polyphosphate (coated with EXOLIT422), melamine cyanurate (particle size 1 to 1)
0 micron), dipentaerythritol (particle size 1-4)
0 micron) and the like were kneaded with a mixing roll at 200 ° C., and then the resin was crushed and press-molded at a temperature of 200 ° C. Length x width x thickness is 5 inches x 1/2
An inch × 1/8 inch test piece was prepared, and flame retardancy was evaluated according to UL94 using the test piece. The results are shown in Table 1.

Comparative Examples 1 and 2 Examples 5 to 5 except that uncoated ammonium polyphosphate (manufactured by EXOLIT422 Hoechst) was used in place of the coated ammonium polyphosphate used in Examples 5 to 8. A flame-retardant resin composition having the same composition as in No. 8 was produced. The results are shown in Table 1.

Comparative Example 3 Example 1 was repeated except that the ammonium polyphosphate having an average particle size of 6 μm in Example 1 was replaced with an average particle size of 120 μm.
I went the same way. As a result, 30 g of ammonium polyphosphate coated with ammonium polyphosphate 3
6.5 g was obtained.

Further, using the coating-processed ammonium polyphosphate obtained above, a flame-retardant resin composition similar to that of Example 5 was prepared and the flame-retardant property was evaluated. The results are shown in Table 1.

[0040]

[Table 1]

Symbol: ML · Cy Melamine cyanurate DPE Dipentaerythritol PP Mitsui Noblene BJH-M (Polypropylene) HIPS Topolex 830 / Block SBR =
90/10 Flame Retardancy Evaluation: UL94 Compliant Sauce: Melt and Dropping 1 PHR of Irganox 1010 was used as an antioxidant in each flame retardant resin composition. Table 2 shows the measurement results of the water-soluble components of the ammonium polyphosphate subjected to the coating treatment and the ammonium polyphosphate not subjected to the coating treatment (EXOLIT422).

[0042]

[Table 2]

[Water-soluble content measurement method] 10 g of a sample (ammonium polyphosphate) was dispersed in 90 g of pure water at 25 ° C.
Continue stirring for 0 minutes. After stirring was stopped, P in the supernatant was
Minutes are measured to determine the amount of dissolved ammonium polyphosphate.

[0044]

EFFECT OF THE INVENTION Ammonium polyphosphate as a flame retardant coated with a vinyl copolymer crosslinked with the polyamine compound according to the present invention has a synergistic effect (s) of the amine compound.
ynergist) shows excellent flame retardant performance when it is made into a flame retardant composition combined with a triazine ring compound or a polyhydric alcohol, and with a smaller addition amount than when using uncoated ammonium polyphosphate. It becomes possible to make the resin flame-retardant, and it is possible to suppress deterioration of the physical properties of the resin composition due to the addition of the flame retardant. Furthermore, the problems of hygroscopicity, water solubility, and lack of affinity with resin, which are the drawbacks of ammonium polyphosphate, can be improved, and the problem of bleeding out at high temperature and high humidity when used as a resin composition, dispersion into resin Sexual problems can be solved.

─────────────────────────────────────────────────── ─── Continuation of the front page (51) Int.Cl. ⁶ Identification code Internal reference number FI technical display area C09K 21/04 // D01F 1/07

Claims (4)

[Claims] 1. An ammonium polyphosphate having a particle size of 0.1 to 100 μm, which is coated with a vinyl copolymer crosslinked with a polyamine compound. 2. The ammonium polyphosphate according to claim 1, wherein the degree of polymerization of the ammonium polyphosphate to be coated is 20 or more. 3. The vinyl copolymer is a glycidyl group,
3. An ammonium polyphosphate according to claim 1, which has an anhydrous carboxyl group and a maleimide group. 4. A particle diameter of 0.1 to 1 coated with a vinyl copolymer (a) crosslinked with a polyamine compound.
A flame retardant composition comprising 00 micron ammonium polyphosphate, (b) triazine ring-containing compound or polyhydric alcohol.