JP2917860B2 - Flame retardant and flame retardant resin composition - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flame-retardant / flame-retardant agent for thermoplastic or thermosetting synthetic resin, paper, fiber or wood, and a resin composition flame-retarded by this flame retardant. It is about things.

[0002]

2. Description of the Related Art Heretofore, as flame retardants for synthetic resins, for example, organic halogen compounds such as chlorinated paraffin and chlorinated oil, tricresyl phosphate, tri- (2,3-dibromopropyl) phosphate, dibromo Phosphorus compounds such as propyl phosphate, antimony trioxide, melamine, or aluminum hydroxide and magnesium hydroxide have been used. However, the organic halogen compounds, phosphorus compounds, and antimony trioxide have problems in that toxic hydrogen halide gas and antimony halide gas are generated during combustion, and that large amounts of black smoke are generated. In addition, when aluminum hydroxide or magnesium hydroxide is used, it is necessary to add a large amount of aluminum hydroxide or magnesium hydroxide in order to impart satisfactory flame resistance and flame retardancy. was there. Furthermore, since these flame retardants are expensive, there is a disadvantage that the cost is high.

Accordingly, many proposals have been made using inexpensive ammonium salts of inorganic acids as flame retardants for synthetic resins. For example, the method described in JP-A-48-83136 is a method in which an ammonium salt of an inorganic acid is mainly used and a small amount of an organic halogen compound is used. Tokiko 55-1
No. 7777 describes a method using mainly an ammonium salt of an inorganic acid and using a small amount of an organic halogen compound and antimony trioxide. JP-A-51-130445
In the publication, a method using an alkaline earth metal carbonate and an inorganic acid ammonium salt is described. Further, JP-A-48-55940 discloses that thermoplastic resin 100
A resin composition comprising 15 to 400 parts by weight of a fine powder of ammonium sulfate or ammonium chloride based on parts by weight is described.

[0004] However, since the inorganic acid ammonium salt is water-soluble, it has a problem in water resistance. When a resin molded product containing the same as a flame retardant is brought into contact with an aqueous substance, the inorganic acid ammonium salt is converted to an inorganic acid ammonium salt. In addition to dissolution, the flame retardancy is impaired, and the physical properties of the resin composition of the molded article and the surface condition of the molded article are deteriorated. It has been found that there is a problem that the ammonium salt absorbs moisture in the air, and furthermore, the ammonium salt is eluted by the absorbed moisture.

Therefore, in order to improve the water resistance of the ammonium salt of an inorganic acid as the flame retardant, a flame retardant whose surface is coated with a water-insoluble film has been proposed. For example, Japanese Unexamined Patent Publication (Kokai) No. 59-191746 discloses a method in which a polysiloxane such as a curable polysiloxane is attached to the surface of a fine powder of a flame-proof ammonium salt such as ammonium sulfate and cured to form a water-soluble powder. A flame-retardant resin composition is described in which an ammonium salt is prevented from being eluted by water so that the ammonium salt content is 5 to 70% based on the whole composition. JP-A-60-6740 discloses polyolefins 0-9.
0% by weight, 5-95% by weight of a modified polyolefin, and a fine powder of an ammonium salt of a flameproof inorganic acid such as ammonium sulfate are subjected to surface treatment with a curable polysiloxane, and then coated with the cured polysiloxane. A flame-retardant polyolefin composition comprising from 5 to 70% by weight of an ammonium salt is described. Japanese Patent Application Laid-Open No. 61-204250 discloses a self-extinguishing polymer material mainly composed of a polyolefin containing an effervescent flame-retardant system comprising a phosphorus component and a carbon-containing nitrogen component. 0
5 mm powdery, free-flowing ammonium polyphosphate 7
A cured polycondensation product consisting of melamine and formaldehyde, an epoxy resin, an aromatic hydroxy compound and formaldehyde, a polycondensation product consisting of a polyol and a polyisocyanate, covering 5 to 99.5% by weight and individual ammonium polyphosphate particles. Or a polyisocyanate, water-insoluble synthetic resin about 0.5 to
A self-extinguishing polyolefin-based polymeric material having improved thermal stability is described, using a product consisting of 25% by weight and having a phosphorus content of about 2 to 30% by weight of the total mixture. . Japanese Patent Application Laid-Open No. 61-223045 discloses that red phosphorus fine particles and ammonium phosphate are added to polyolefin, the total amount of red phosphorus and ammonium phosphate is 10 to 30% by weight, A flame retardant polyolefin composition having a ratio of 99: 1 to 1:99 is described. JP-A-63-20
No. 2639, 100 parts by weight of polyolefin resin or polystyrene resin, 100 parts by weight of ammonium sulfate
10 to 10 parts by weight, the average particle size is 0.4 to 30 μm,
And a flame retardant resin composition containing 10 to 150 parts by weight of aluminum hydroxide having a DOP oil absorption of 35 ml / 100 g or less. This is due not only to the problem of water resistance due to the water solubility of ammonium sulfate, but also to the fact that aluminum hydroxide begins to thermally decompose at about 200 ° C. However, the problem of foaming in an extreme case is to solve both the water resistance of ammonium sulfate and the foaming property of aluminum hydroxide by using ammonium sulfate and aluminum hydroxide in combination. Further, JP-A-64-70561 discloses a polymer 10
0 parts by weight, as a flame retardant, a heat-resistant polymer material containing 5 to 50 parts by weight of a phosphorus-nitrogen component such as polyammonium polyphosphate and 50 to 175 parts by weight of aluminum hydroxide is described, and as the polyammonium polyphosphate, Polycarbodiimide, polyurethane, polyisocyanurate,
It describes that individual ammonium polyphosphate particles are coated with a water-insoluble synthetic resin such as polyurea, melamine / formaldehyde resin, epoxy resin and the like. Further, JP-A-1-108261 discloses, as a flame protective agent, a phosphorus / nitrogen component obtained by coating ammonium polyphosphate particles with a water-insoluble synthetic resin, aluminum hydroxide,
A flame-retardant polymer composition containing an organic nitrogen compound, a polyhydric alcohol and the like is described.

[0006]

In any of the above methods, a flame-retardant method using an ammonium salt of an inorganic acid is used to form a water-insoluble film on the surface of the ammonium salt and waterproof the surface. This solves the problem of water resistance caused by the water solubility of the ammonium salt of an inorganic acid. However, according to the research results of the present inventors, it has been found that the flame retardant comprising the ammonium salt of an inorganic acid has problems other than the above-mentioned water resistance. That is, conventionally, a flame retardant comprising an ammonium salt of an inorganic acid is used as a raw material by preparing a powder having a size of 100 μm or less using a pulverizer. The decomposition temperature of the ammonium salt of inorganic acid is 300
It is assumed that the temperature is at least ℃. However, in fact, it was found that the ammonium salt of the inorganic acid gradually started to decompose at around 120 ° C. However, for example, the molding temperature of a thermoplastic resin generally needs to be 200 ° C. or higher. In addition, the standard of flame retardancy test of paper is that it is not discolored or deteriorated by hot air of 200 ° C.
A conventional ammonium salt of an inorganic acid whose decomposition starts gradually from the vicinity is decomposed in the process of resin molding and cannot withstand the flame retardancy test of paper. Similarly, the film for waterproofing is 2
Although heat resistance of 00 ° C. or higher was required, it was also found that sufficient water resistance could not be obtained only by waterproofing with a water-insoluble film.

[0007] Incidentally, the present inventors pulverized ammonium sulfate particulates to about 40 μm with an atomizer type pulverizer,
25% by weight of a fine powder of ammonium sulfate sufficiently dried at 110 ° C for 1 hour in a drier and 75% by weight of polypropylene were mixed, and injection molding was performed at a molding temperature of 220 ° C.
As a result, the surface of the molded article had a flash phenomenon due to the decomposition and evaporation of water of crystallization, and was in a foamed state. In addition, a large amount of ammonium odor was generated during molding, and further, corrosion of the mold due to decomposition and evaporation of sulfuric acid was observed. Also, regarding the flame retardancy, satisfactory flame retardancy was not obtained due to a shortage in quantity due to decomposition of the flame retardant.

Further, when the above ammonium sulfate fine powder is used as a flame retardant, there is a problem in its shape. That is, the fine powder of ammonium sulfate pulverized by a pulverizer as in the prior art was an inorganic substance having an irregular particle shape and a jagged surface, and the fine powder was very hard and brittle. For this reason, when a curable resin film or the like is formed on the surface of such a fine powder for the purpose of waterproofing, the adhesion of the film to the surface of the fine powder is extremely weak and unstable. As a result, even with a slight mixing operation or friction, the uneven surface or the hard and brittle fine powder itself is damaged, and the waterproof film on the surface is peeled off, and satisfactory waterproofness cannot be obtained. Furthermore, it was found that the film was easily broken due to the evaporation of the water of crystallization of ammonium sulfate and the decomposition of unstable sulfuric acid and ammonium gas, and the desired waterproofing effect could not be obtained.

Accordingly, the present invention provides a method for producing an inorganic acid as described above .
In view of the problems of conventional flame retarding methods using ammonium salts, it can withstand the heating during molding of synthetic resins and various flame retardant tests as a flame retardant for synthetic resins, paper, fibers, wood, etc. An object of the present invention is to provide a flame retardant capable of imparting sufficient heat resistance and sufficient water resistance, and a flame retardant resin composition using the same.

[0010]

The inventors of the present invention have conducted intensive studies to achieve the above object, and have found that the inorganic acid ammonium
Removing the water of crystallization unsalted contains, also, ammonium
Ammonium salt having good heat resistance and water resistance as a flame retardant by removing acid components such as sulfuric acid components and unstable components such as ammonium components contained in the ammonium salt at about 120 ° C. The inventors have found that the present invention can be performed, and have completed the present invention. Further, in this case, since the ammonium salt is water-soluble, it was also confirmed that the surface of the ammonium salt had to be waterproofed.

That is, the present invention according to claim 1 provides an inorganic acid
After dissolving the ammonium salt of a solid water, a flame retardant comprising a particulate ammonium salt formed was recrystallized by adding and mixing an insoluble solvent ammonium salt <br/>. The recrystallized ammonium salt is in the form of fine particles having a particle diameter of generally not more than 100 μm.

As a method for recrystallizing an ammonium salt to remove an acid component such as a sulfuric acid component and an unstable component such as an ammonium component, for example, an ammonium salt may be used.
There is also a method of evaporating water by heating an aqueous solution of a monium salt . However, in this method, the viscosity increases with the evaporation of water, causing a problem in stirring, and the crystal size of the recrystallized crystals is not uniform because some crystalline substances and water-soluble substances are formed, which is not suitable for the purpose of the present invention. . Accordingly, a method using an insoluble solvent as described above is preferable.

The ammonium salt of an inorganic acid includes ammonium sulfate, ammonium phosphate, ammonium tripolyphosphate, ammonium hydrochloride, ammonium borate, ammonium bromate, ammonium sulfamate,
And ammonium imido disulfonate. Among them, ammonium sulfate, ammonium phosphate, or ammonium tripolyphosphate is preferably used. These ammonium salts of inorganic acids are used alone or in combination of two or more.

The concentration of these ammonium salts dissolved in water is determined by the amount of ammonium salts saturated in water. For example, in the case of ammonium sulfate (ammonium sulfate), the amount of industrial ammonium sulfate dissolved in 100 g of water is:
72.4 g (42.0%) at 10 ° C;
0 g (42.9%) and 80.5 g (44.6%) at 40 ° C.
%) At 50 ° C. is 83.8 g (45.6%).
The dissolution amount of the second ammonium phosphate in 100 g of water was 57.5 g (36.5%) at 10 ° C, 58.0 g (36.7%) at 20 ° C, and 59.2 g (3
7.2%) and 62.0 g (38.3%) at 50 ° C. Therefore, in the present invention, the concentration when the ammonium salt is dissolved in water for recrystallization is preferably not more than the above-mentioned saturated solubility.

Next, the ammonia dissolved in water as described above is used.
Examples of the insoluble solvent of an ammonium salt for recrystallizing an ammonium salt include alcohols such as methanol, ethanol and isopropyl alcohol, esters such as methyl cellosolve acetate, and ethers such as methyl cellosolve and ethyl cellosolve. . The amount of the insoluble solvent required to recrystallize the ammonium salt from the aqueous solution is, for example, the saturated solubility at 20 ° C.
To recrystallize ammonium sulfate from an aqueous solution of ammonium sulfate in which 9% of ammonium sulfate was dissolved in 40 g of ammonium sulfate to 40 g of water (40%), 60 g of methanol, 200 g of isopropyl alcohol, 60 g of methyl cellosolve, and 60 g of methyl cellosolve, , 150 g of ethyl cellosolve are required.

Further, the invention according to claim 5 has the above-mentioned configuration.
A flame retardant formed by coating the surface of an ammonium salt with a water-insoluble waterproof film. Examples of the water-insoluble waterproof film include oils and fats, a coupling agent, and a curable synthetic resin. As the fats and oils, those which are insoluble in water and have a boiling point of 180 ° C. or higher are used. For example, such fats and oils include soybean oil, coconut oil, linseed oil, cottonseed oil, rapeseed oil, castor oil, phosphate esters, phthalate esters, fatty acids, basic acid esters, dihydric alcohols used as plasticizers Esters and oxyacid esters. Also, as a resin liquid, liquid polybutadiene,
Liquid rubber, dicyclopentadiene petroleum resin (DCPD
Resin) and butyral resin. Further, examples of the oil-based organic acids include oleic acid, myristic acid, isotridecyl myristate, palmitic acid, stearic acid, isostearyl alcohol, dimer acid, and isostearic acid. Other examples include silicone oil and spindle oil. Examples of the coupling agent include zirconium-based, silane-based, titanate-based, and aluminum-based coupling agents. Examples of the curable resin include an amino resin, an epoxy resin, an alkyd resin, a urethane resin, an acrylic resin, a xylene resin, and a DAP resin. Further, as a resin, cellulose-based ethyl cellulose (EC), carboxymethyl cellulose (CM)
C), polyvinyl alcohol (PVA), and isoprene phthalic resin. These can be used alone or in combination of two or more.

This waterproof coating is 0.2% by weight or more, preferably 0.2% by weight, based on the ammonium compound.
10% by weight, more preferably 0.5% by weight to 5% by weight.
% By weight.

Further, the invention according to claim 8 is characterized in that ammonium
In a water-alcohol mixture in which the salt is recrystallized into a fine powder,
At least one of aluminum acrylate, zinc sulfate, or potassium sulfate is mixed, and polyvinyl alcohol (PVA) or a polyol and polyisocyanate are added to the mixture to form a curable resin on the surface of the fine ammonium salt powder crystal. This is a method for producing a flame retardant formed with a waterproof coating. That is, conventionally, in a water-alcohol mixture, P
Even if an attempt is made to form a curable film by reacting VA or a polyol with a polyisocyanate, the reaction rate between the polyisocyanate and water or alcohol is high, and the polyisocyanate gels instantaneously, thereby forming a film. Was difficult. Therefore, by mixing the above-mentioned aluminum acrylate, zinc sulfate, potassium sulfate or the like slightly dissolved in water or alcohol, instantaneous gelation of the polyisocyanate is prevented, and ammonium is mixed in a water-alcohol mixture.
It has become possible to form a curable film on the surface of the salt .

Furthermore, according to claim 9 invention, a flame retardant which comprises as an ammonium salt flame retardant as described above is 15 parts by weight to 100 parts by weight per 100 parts by weight of the resin component It is a conductive resin composition. A as the flame retardant
If the ammonium salt is 15 parts by weight or less based on the resin component, a sufficient flame retarding effect cannot be obtained. As the content of the ammonium salt increases, the flame-retardant effect increases, but on the other hand, the mechanical strength of the molded article is reduced, and the physical properties of the resin are deteriorated. Therefore, the content exceeding 100 parts by weight is not preferable. . As described above, conventional aluminum hydroxide, magnesium, melamine, and the like can also be made flame-retardant.
It is necessary to add 0 parts by weight or more, and there is a possibility that the physical properties of the resin may be deteriorated.

The resin component of the resin composition containing the flame retardant may be either a thermoplastic resin or a thermosetting resin. As the thermoplastic resin, polyethylene, polyolefin resin such as polypropylene, polyacetal,
Polyvinyl resins such as polystyrene, polymethyl methacrylate, polyvinyl acetate, and polyvinyl alcohol; polyamide resins such as ethylene-vinyl acetate copolymer, nylon; polyester resins such as polyethylene terephthalate and polycarbonate; acrylonitrile butadiene styrene resin (ABS resin); acrylonitrile Styrene resin (A
S resin) or other homo- or copolymers such as polyether resin, styrene-butadiene rubber (SBR), acrylonitrile-butadiene rubber (NB
R), elastic polymers such as polybutadiene and polyisoprene. The thermosetting resin includes unsaturated polyester, polyurethane, and epoxy resin.

The above resin composition contains the above ammonium hydroxide.
Other flame retardants such as organic halides, phosphorus compounds, antimony trioxide, aluminum hydroxide, magnesium hydroxide and the like can be used in combination with the flame retardants composed of a metal salt .

Further, in addition to the above flame retardant, various fillers such as antioxidants, ultraviolet absorbers, various pigments, inorganic fillers, glass fibers and inorganic fibers are added to the resin composition. You can also.

When the resin component is a thermoplastic resin, the resin composition contains the above-described flame retardant and, if necessary, an antioxidant, an ultraviolet absorber, various stabilizers, a pigment, and a filler. Is mixed and kneaded, and the mixture is powdered or granulated to form a molding material, or is directly formed into a film, sheet, rod, tube, or any other shape by a conventional method. In the case of a thermosetting resin, a resin composition in which a flame retardant and other additives are added to a resin component is heated or cured with a curing agent.

[0024]

[Action and Effect of the Invention] As described above, in the present invention, no
As the flame retardant is obtained by dissolving the ammonium salt of mechanical acid in water and recrystallizing it, unstable compounds that decompose at low temperatures, such as ammonium components and acid components such as sulfuric acid, dissolve in water. Sometimes washed out in water and removed,
At the same time, the water of crystallization is also removed, so that a flame retardant having an ammonium salt decomposition temperature of about 300 ° C. and having sufficient heat resistance can be obtained. By containing it, the intended flame retardancy can be imparted to synthetic resin, paper, fiber, wood and the like. Further, by removing the instability and the ammonium component and the acid component as described above, for example, a large amount of ammonium odor is generated during molding of a synthetic resin,
The mold does not corrode due to the decomposition and evaporation of the acid component. Also, even when a water-resistant film is formed on the surface of the ammonium salt, the film is easily damaged due to evaporation of water of crystallization of ammonium sulfate and decomposition of unstable sulfuric acid or ammonium gas, and a desired waterproof effect is obtained. There is no such thing as not being able to be done. Further, as is apparent from FIG. 1, the ammonium salt recrystallized from the aqueous solution in the present invention becomes a fine powder having a substantially spherical shape and a smooth surface, unlike conventional pulverized products. Therefore, when a waterproof coating is formed on the surface, the adhesive strength with the coating is large, the coating is not damaged or peeled off by mixing or friction, and the water resistance of the coating against ammonium salts is improved. It can be granted.

[0025]

【Example】

<Example 1> ( Preparation of finely powdered recrystallized product of ammonium salt ) FIG. 2 schematically shows an apparatus used for recrystallization. In FIG. 2, reference numeral 1 denotes a solvent tank containing methyl cellosolve, which is an insoluble solvent of an ammonium salt , and an air compressor (not shown) is connected to the solvent tank 1 via a pressure regulating device 4. The urethane hose 5 positioned at the bottom of the solvent tank 1 is shown in FIG. 3 by a liquid feed pipe 5 ′ provided through a stirring shaft 7 of the stirrer 2 via a rotary valve 6 for adjusting the flow rate of the solvent. Thus, it is connected to the solvent discharge nozzle 9 attached to the stirring blade 8 located at the bottom in the crystallization vessel 3. In this apparatus, 400 g of ammonium sulfate granules were added little by little while stirring 600 g of warm water at 50 to 60 ° C. in the crystallization vessel 3 to prepare 1,000 g of a 40% aqueous ammonium sulfate solution at 1200 rpm × 30 minutes. Next, while the rotation speed of the stirring shaft 7 of the stirrer 2 is lowered to 900 rpm and stirring is continued, the pressure of the compressed air from the air compressor is adjusted by the pressure regulating device 4 while the methyl cellosolve is dissolved from the solvent tank 1 by the compressed air. As shown in FIG. 3, the pressure is fed through a urethane hose 5 and the flow rate is adjusted by a rotary valve 6 to a stirring blade 8 located at the bottom of the crystallization vessel 3 through a liquid feed pipe 5 ′ in a stirring shaft 7. Methyl cellosolve was gradually added to the aqueous solution of ammonium sulfate in the crystallization vessel 3 from the tip of the nozzle 9 provided. 800 g of methyl cellosolve was added, and about 380 fine spherical crystals of ammonium sulfate were obtained.
g was recrystallized. Observation of this fine spherical crystal with a micrograph revealed that it had a particle size of about 10 to 40 μm.
When ammonium sulfate was dissolved in water, a considerable amount of ammonium odor was recognized, and free acid was also eluted.

Example 2 (Surface Treatment with Zirconate) 1000 g of a fine spherical recrystallization solution of ammonium sulfate prepared in the same manner as in Example 1.
(380 g of ammonium sulfate solid content)
While stirring at 1200C (1200 rpm), a tetra-n-butyl zirconate solution (Daiichi Kagaku Kagaku Kogyo Co., Ltd.) was added at 3% by weight (11.4 g) based on the solid content of ammonium sulfate.
After adding and stirring for 15 minutes, the powder sample A having a zirconate waterproof film formed on the surface was obtained by spray drying using a spray dryer (manufactured by Okawara Seisakusho, model: pilot series L-8).

Example 3 (Surface Treatment with Titanate Coupling Agent) A phosphate-based titanate coupling agent (manufactured by Ajinomoto Co., Inc.)
A solution obtained by diluting KR138S (product name: KR138S) with IPA at a ratio of 50:50 was added in the same manner as in Example 2 so as to be 5% by weight (2.5% by weight with a coupling agent) based on the solid content of ammonium sulfate. After a reaction treatment for 5 minutes, the powder sample B was spray-dried with a spray dryer to obtain a powder sample B having a waterproof coating of a titaner coupling agent formed on the surface.

<Example 4> (Surface treatment with zirconate and curable acrylic resin) After the zirconate treatment in Example 2, a curable acrylic resin (manufactured by Dainippon Ink Co., Ltd., product name: Acrydic A801P-50) was further applied. 50 in methyl alcohol:
The solution diluted to 50 was treated with ammonium sulfate solids (380
g) to 4% by weight (15.2 g) and mixing at 800 rpm for 10 minutes to form a crosslinked cured film of zirconate and acrylic resin, and spray-drying with a spray dryer to give a surface Powder sample C on which a waterproof coating of zirconate and a curable acrylic resin was formed was obtained.

Example 5 (Surface Treatment with Self-Crosslinking Acrylic Resin) To 1000 g of microsphere recrystallized ammonium sulfate (solid content of ammonium sulfate: 380 g) prepared in the same manner as in Example 1,
A self-cross-linking acrylic resin (manufactured by Hoechst Synthetic Co., Ltd., product name: DM710) was added at 2% by weight (7.6 g) based on the solid content of ammonium sulfate, and mixed at 800 rpm for 5 minutes. Was charged at 20% (1.52 g) with respect to the solid content of the acrylic resin, reacted for 20 minutes, and spray-dried with a spray dryer to obtain a powder sample D having a self-crosslinking allyl resin waterproof film formed on the surface. Obtained.

Example 6 (Surface Treatment with Amino Resin (Melamine Resin)) 1000 g of ammonium sulphate recrystallized liquid prepared in the same manner as in Example 1 (solid content of ammonium sulfate: 380 g)
While stirring at 50 ° C., melamine resin (manufactured by Sumitomo Chemical Co., Ltd., product name: Sumitex Resin M-3; solid content 50)
%) Aqueous solution was added to a solid content of 2% by weight (7.6 g) with respect to the solid content of ammonium sulfate. After mixing for 10 minutes, the temperature was raised to 70 ° C., and the acid catalyst paratoluenesulfonic acid (50% with isopropyl alcohol) was added. : 50), and mixed for 5 minutes.
The mixture was mixed for 0 minute and spray-dried with a spray dryer to obtain a powdery substance having a melamine resin waterproof film formed on the surface. Further, the powdery material is dried with a dryer for 120 minutes.
C. for 60 minutes to complete a cured waterproof coating. Since some aggregates were formed, 10% of a dispersant of 1: 1 mixture of bisamide and magnesium stearate was mixed and treated with an atomizer pulverizer to obtain a powder sample E having a cured melamine resin waterproof film formed on the surface. Obtained.

Example 7 (Surface Treatment with Epoxy / Amine Curable Resin in Liquid) A water-soluble polyamine (Hoechst Japan Co., Ltd.) was added to 10 parts by weight of a water-dispersed epoxy resin (Beccopox EP128, manufactured by Hoechst Japan Co., Ltd.). Made by company, product name:
6 parts by weight of EH623W) were mixed to form a gel-like initial condensate in about 10 minutes, and the mixture was stirred at 40 ° C. with 1000 g of a fine spherical recrystallized ammonium sulfate solution (380 g of ammonium sulfate solid content) obtained in the same manner as in Example 1. While adding 11.4 g of the epoxy condensate and treating at 65 ° C. for 20 minutes, the mixture was spray-dried with a spray drier.
Powder sample F with epoxy resin waterproof coating formed on the surface
I got

Example 8 (Surface Treatment with Epoxy Resin and Silicone Oil)
The powder sample F having the cured epoxy resin film obtained in Example 7 was further mixed with 4 g of silicone oil for the purpose of preventing secondary agglomeration and oil coating, and then spray-dried with a spray drier to obtain an epoxy resin on the surface. And powder sample F- on which a waterproof coating of silicone oil was formed
1 was obtained.

<Example 9> (Surface treatment with dioctyl phthalate (DOP)) DOP (diluted 1:10 with methanol) while stirring the microcrystalline recrystallized solution of ammonium sulfate prepared in the same manner as in Example 1 was continued. Daihachi Chemical Co., Ltd.) and mix 5
After a minute, the sample was spray-dried with a spray dryer to obtain a powder sample G having a DOP waterproof film formed on the surface.

<Example 10> (Surface treatment with silicone oil) In the same manner as in Example 9, a silicone oil (manufactured by Toray Industries, Inc.) diluted 1:10 with methanol was added to the ammonium sulfate fine recrystallization liquid. After 5 minutes of mixing, the mixture was spray-dried with a spray dryer to obtain a powder sample H having a silicone oil waterproof film formed on the surface.

Example 11 (Surface Treatment with Silane Coupling Agent and Silicone Oil) The silane coupling agent was heated at 60 ° C. while stirring the microcrystalline recrystallized solution of ammonium sulfate prepared in the same manner as in Example 1. 6.0 g of a ring agent solution (manufactured by Toray Dow Corning Co., Ltd., product name: AY43-004) was added, and 1
After mixing for 0 minutes, silicone oil (SF8416:
Toray Dow Corning Co., Ltd.) Add 4 g, mix for 5 minutes, and spray dry with a spray dryer to obtain
A powder sample I having a surface on which a waterproof coating of a silane coupling agent and silicone oil was formed was obtained.

Example 12 (Surface Treatment with Polyvinyl Alcohol (PVA) and Polyisocyanate) The microsphere recrystallization liquid of ammonium sulfate prepared in the same manner as in Example 1 was continuously stirred.
PVA (Kuraray Co., Ltd., product name: Kuraray Povar No. 1)
17) After adding 60 g of a 10% aqueous solution and mixing for 5 minutes, adding 33 g of an aqueous zinc sulfate solution obtained by converting zinc sulfate powder into a 30% aqueous solution at 60 ° C. with hot water and mixing for 3 minutes, and then adding a non-yellowing polyisocyanate (Sumitomo Bayer Urethane Co., Ltd.) 10.67 g of a 2-fold diluted solution of ethyl acetate (manufactured and manufactured by Sumidur N-75; solid content: 75%) was added, followed by di-n-butyltin dilaurate (manufactured by Sakai Chemical Industry Co., Ltd., product name:
2.0 g of a 0.5% ethyl acetate solution of TN12) was added, mixed 20 minutes later, and spray-dried with a spray drier to obtain a powder sample J having a waterproof film of polyvinyl alcohol and polyisocyanate formed on the surface. .

<Example 13> (Surface treatment with silane coupling agent, PVA, polyisocyanate) While continuing to stir the microsphere recrystallized solution of ammonium sulfate prepared in the same manner as in Example 1, 6
The solution was heated to 0 ° C. and the solution of silane coupling agent (manufactured by Toray Dow Corning Co., Ltd., product name: AY43-004) was added to 6.0.
g, and after mixing for 10 minutes, 60 g of a 10% aqueous solution of PVA (Dainippon Gosei Chemical Co., Ltd .: GL-05) is added and mixing is continued, and 33 g of a 30% aqueous solution of zinc sulfate powder is added.
Non-yellowing polyisocyanate (manufactured by Sumitomo Bayer Urethane Co., Ltd., product name: Sumidur N-75; solid content 75)
%) Of ethyl acetate, followed by adding 0.5% of ethyl acetate of catalyst di-n-butyltin dilaurate (trade name: TN12, manufactured by Sakai Chemical Industry Co., Ltd.).
After adding 2.0 g of the solution and mixing for 20 minutes, the mixture was spray-dried with a spray drier to obtain a powder sample K having a surface on which a waterproof coating of a silane coupling agent, PVA, and polyisocyanate was formed.

Example 14 In the following examples, powder samples F-1, G, H, and I obtained in the above examples were used as flame retardants as they were. For powder samples A, B, C, D, E, F, J and K, these were mixed with a dispersant (zinc stearate and bisamide = 5: 5) and 8
5% by weight: 15% by weight were mixed and the secondary agglomeration was eliminated using an atomizer pulverizer, and each of them was used as a flame retardant.

(Example 15) Each of the powder samples F-1,
20% by weight of G, H and I, 80% by weight of PP resin (manufactured by Idemitsu Petrochemical Co., Ltd., product name: J-700G), and powder samples A, B, C, D, E, F, J, K
And 23% by weight of the same PP resin and 77% by weight of the same PP resin, respectively, and using an injection molding machine (manufactured by Toyo Seiki Co., Ltd., type: TS-100) at a molding temperature of 220 ° C. and a thickness of 3.18 mm A test piece having a width of 12.7 mm and a length of 127 mm was injection molded.

Example 16 Each of the powder samples F-1,
30% by weight of G, H, and I and 70% by weight of an ABS resin (manufactured by Daicel Chemical Industries, Ltd., product name: Sebian V-320);
In addition, each powder sample A, B, C, D, E, F,
35% by weight of J and K and 65% by weight of the same ABS resin were mixed, and the same test piece as in Example 15 was injection molded at a molding temperature of 250 ° C. using an injection molding machine.

Each of the injection molded articles obtained in Examples 15 and 16 was examined for flammability, surface properties, and water resistance. The results are shown in Tables 1 and 2 below.

Incidentally, the combustion test was conducted in accordance with the U.S. UL standard (Und
erwriters Laboratories In
c. ) 94 V-0.

The outline of the UL standard 94V-0 is as follows. (1) Request A. Flaming after contact with any specimen is less than 10 seconds. B. Flaming after 10 sets of flames in a set of 5 pieces within 50 seconds in total. C. Do not flaming or glowing until the clamp. D. Do not drip flaming particles that ignite cotton under 12 inches (305mm). E. FIG. Remove the second flame and glowing within 30 seconds. If one of the five test pieces does not meet this requirement, or if the sum of the five flaming times is 51 to 55 seconds, test one set of five. (2) Instrument A. Chambers, enclosures and laboratory hoods without ventilation. B. Do not use stabilizers such as Bunsen or Tirrill burners or end attachments with a tube length of 4 inches (102 mm) and an inside diameter of 3/8 inches (9.5 mm). C. Ring stand with clamp. D. Industrial grade of methane gas ^{(1000Btu / ft 3 (37MJ /} m
³ ) The same result can be obtained) and regulator and flow meter. E. FIG. Stopwatch or other timer. F. Dry surgical cotton, size 2 "x 2", freestand 1/4 "thick. G. FIG. Desiccator containing anhydrous calcium chloride. H. Pretreatment room or chamber: 23 ± 2 ℃, 50 ± 5% R
What can be kept at H. I. Pre-treatment oven: air circulation type, which can be maintained at 70 ± 1 ° C. (3) Specimen 5 inches (127 mm) long and 0.5 inches (12.7 mm) wide. Thickness: (1) Minimum and maximum, and intermediate thickness. (2) Maximum thickness is 0.5 inch (12.7 mm).
(3) The thickness increase between the minimum and maximum thickness shall not exceed 0.125 inches (3.18 mm). A. Maximum width is 0.52 inch (13.2mm) B. The edges are smooth and the corner R is 0.05 inch (1.27m
m). If there is a range of color, melt flow and reinforcing material, a test piece representative of each range is also prepared. Provide that the test results are essentially the same, one representing the natural, light and dark color ranges and one representing the limits and ranges of melt flow and reinforcement content. In the case of different flammability characteristics, the color, melt flow, and reinforcement content are tested to limit the material, or additional test pieces of intermediate color, melt flow, and reinforcement content are prepared. (4) Pretreatment A. 5 pieces Treated at 23 ± 2 ° C and 50% RH for 48 hours. B. After treating at 70 ° C. for 168 hours, the mixture is cooled in a desiccator containing anhydrous calcium chloride (room temperature) for 4 hours or more. (5) Test Perform the test without draft. Laboratory hoods are preferred. Fig. 4 shows the relationship between the test piece and the burner. The burner ignites away from the specimen and adjusts the height of the blue flame without yellow tip to 3/4 inch. Place the test flame in the center of the lower end of the test piece for 10 seconds, remove it and remove it by 6 inches or more.
Record the ing time. As soon as the flaming of the test piece has ceased, remove the test flame for 10 seconds and record the flaming and glowing time. If the test piece melts and drip during flame contact or drops with a flame, tilt the burner to 45 degrees to prevent the drop from entering the burner tube, or
Slightly offset from 1/2 inch side. For test pieces that have melted or flamed drops during the test, or that burn, the burner should be supported by hand during flame contact and the burner tip and the lower end of the test piece should be 3 /
Keep at 8 inches (9.5mm). Ignore the melted thread of the material,
Flame contacts main part of test piece. Observe and record the following: A. Flaming time after applying the first test flame. B. Flaming time after applying the second test flame. C. Flaming and glowing time after applying the second test flame. D. Whether the specimen burned to the support clamp. E. FIG. Whether the specimen drip flaming particles that ignite the cotton.

<Surface Properties> The surface properties were determined by visually observing the surface of the molded test piece.・ Criterion ◎: Very smooth without unevenness. ：: smooth without irregularities. Δ: Fine irregularities are partially observed, but almost smooth. ×: Many fine irregularities are present.

<Water resistance test> In the water resistance test, the test piece was heated to 50 ° C.
Was immersed in warm water for 24 hours, and changes in the surface were visually observed and judged. Criteria ○: Smooth without irregularities. Δ: Fine irregularities are partially observed, but almost smooth. X: Many fine irregularities exist.

[0046]

[Table 1]

[0047]

[Table 2]

<Comparative Example> (Flame-retardant treatment with pulverized ammonium sulfate) (1) Ammonium sulfate for industrial use (manufactured by Mitsubishi Chemical Corporation)
Pulverized with an atomizer type pulverizer and averaged 4
A 5 μm pulverized ammonium sulfate was prepared. (2) A silane coupling agent (manufactured by Toray Dow Corning Co., Ltd., product name: AY43-004) is treated with methanol in 10
A solution diluted at a ratio of 0: 100 was prepared. (3) 100 g of the above-mentioned pulverized ammonium sulfate was put into a mixer, 5 g of the silane coupling agent solution was further added, and the mixture was mixed at 6000 rpm for 5 minutes to treat the surface of the pulverized ammonium sulfate with a silane coupling agent. However, in the above surface treatment, the mixing was stopped at the time of mixing for 3 minutes, and the vapor of methanol was discharged. After mixing for 5 minutes, further add 10 g of zinc stearate as a dispersant.
Add and mix for 1 minute to complete the process. (4) A mixture of 77% by weight of the same PP resin (manufactured by Idemitsu Petrochemical Co., Ltd., product name: J-700G) and 23% by weight of the above-mentioned ammonium sulfate treated with a silane coupling agent was used. , Examples 15 and 1
As a result of examining the flammability, surface properties, and water resistance in the same manner as described above for the test piece injection-molded in the same manner as in Example 6, the flame retardancy was rejected, and the surface of the test piece showed fine foam. Many surface irregularities were observed, the surface properties and water resistance were poor, and it was found that the surface coating film of ammonium sulfate with the silane coupling agent was incomplete.

From the results of Examples 15 and 16 and Comparative Example shown in Tables 1 and 2, all of the flame retardant resin compositions using the flame retardant according to the present invention have excellent flame retardancy. It is clear that the surface of the molded article has no irregularities and is smooth and has excellent water resistance.

[Brief description of the drawings]

FIG. 1 is a drawing showing a micrograph of an ammonium sulfate crystal recrystallized from a water-alcohol mixture according to the present invention.

FIG. 2 is a schematic view of an apparatus used for recrystallization of ammonium sulfate in the present invention.

FIG. 3 is an enlarged view of a recrystallization container part in the apparatus.

FIG. 4 is a drawing showing a relationship between a test piece and a burner in a combustion test based on UL standard 94V-0.

[Explanation of symbols]

1: solvent tank, 2: stirrer, 3: crystallization vessel, 4: pressure regulator, 5: urethane hose, 5 ': liquid feed pipe, 6: rotary valve, 7: stirring shaft, 8: stirring blade, 9: nozzle.

Continued on the front page (51) Int.Cl. ⁶ Identification code FI D06M 11/00 Z

Claims (9)

(57) [Claims] [Claim 1] After solid ammonium salt of an inorganic acid dissolved in water, flame retardant agent comprising a particulate ammonium salt formed was recrystallized by adding and mixing an insoluble solvent of the ammonium salt. 2. The recrystallized ammonium salt having a particle size of 100
The flame retardant according to claim 1, which is in the form of fine particles having a particle size of not more than μm. Wherein the ammonium salts of inorganic acids, ammonium sulfate, claim 1 is at least one selected ammonium phosphate, or tripolyphosphate ammonium
The flame retardant described. 4. The flame retardant according to claim 1, wherein the insoluble solvent of the ammonium salt is at least one selected from methanol, ethanol, isopropyl alcohol, methyl cellosolve acetate, methyl cellosolve, and ethyl cellosolve. 5. The flame retardant of claim 1 to claim 4, flame retardant, characterized by comprising the surface of the particulate ammonium salt and coated with a water-insoluble waterproof coating. 6. The flame retardant according to claim 5 , wherein the water-insoluble waterproof film is a fat or oil, a coupling agent, or a curable synthetic resin. 7. 0.2% by weight based on ammonium salt
The flame retardant according to claim 5 or 6 , wherein the flame retardant is coated with a water-insoluble waterproof film of 10 to 10% by weight. 8. A water-alcohol mixture obtained by recrystallizing a fine powder of an ammonium salt of an inorganic acid is mixed with at least one of aluminum acrylate, zinc sulfate and potassium sulfate, and polyvinyl alcohol or polyol is added thereto. And a polyisocyanate to form a waterproofing film on the surface of the recrystallized finely powdered ammonium salt . 9. The flame retardant of claim 1 to claim 7, ammonium salt per 100 parts by weight of the resin component 1
A flame-retardant resin composition, which is contained in an amount of 5 parts by weight to 100 parts by weight.