JPS63346A - Red phosphorus flame retarder and flame-retardant resin composition - Google Patents

Abstract

PURPOSE:To provide a flame-retardant resin compsn. having excellent resistance to moisture and corrosion, consisting of an epoxy resin, a specified red phosphorus flame retarder, Al(OH)3, a curing agent and a curing accelerator. CONSTITUTION:Yellow phosphorus is heated at 250-600 deg.C in a closed vessel purged with an inert gas to convert not more than 70% of yellow phosphorus into red phosphorus. Unconverted yellow phosphorus is distilled off to obtain spherical red phosphorus (aggregate) having an average particle size of several mu-200mu and no shattered surface. 10-100pts.wt. said red phosphorus and 5-30wt% water-soluble Al or Zn salt are added to 100pts.wt. water. The mixture is neutralized to obtain a Al(OH)3 or Zn(OH)2-coated red phosphorus flame retarder (B). 100pts.wt epoxy resin (A) is blended with 5-40pts.wt. component B, 5-150pts.wt. Al(OH)3 (C), a curing agent (D) (e.g., phthalic anhydride) and a curing accelerator (E) (e.g., 2-phenylimidazole).

Description

[Detailed Description of the Invention] <Technical Field of the Invention> The present invention relates to a red phosphorus-based retardant and a thermosetting resin composition containing the same. This is intended to improve the moisture resistance and corrosion resistance of flame retardants and resin compositions.

<Background of the Invention> Red phosphorus flame retardants are useful for flame retardant thermosetting Pi4 resins, especially epoxy resins and resins, and are used as insulation materials for impregnating and casting high L'c'i electronic components. It is used in products.

Red phosphorus itself can be used as a flame retardant, but because red phosphorus is unstable to heat, friction, and yRl, it is dangerous to store it or mix it with synthetic resin, and it also There are several problems with the direct use of red phosphorus, such as reacting with moisture in the water to generate toxic phosphine gas and contaminating the working environment. 2. Red phosphorus is not compatible with synthetic resins and causes problems in work. Conventional red phosphorus flame retardants have attempted to solve these problems by stabilizing red phosphorus with various organic or inorganic substances.

However, in recent years, with the miniaturization and higher voltage of electrical equipment, and the demand for higher performance electrical insulating materials, the requirements for the physical properties of red phosphorus flame retardants have also become stricter. The situation has become difficult to deal with.

In other words, electronic components insulated with conventional resins containing red phosphorus flame retardants lack durability and reliability due to deterioration of the resin over time, resulting in poor insulation and corrosion of metal parts, resulting in decreased performance. It has been pointed out that this is mainly caused by the deterioration of the red phosphorus flame retardant, and there is a need for improvement. The deterioration of red phosphorus flame retardants is said to occur when red phosphorus reacts with trace amounts of moisture, producing phosphine and corrosive oxidation products. Although attempts have been made to stabilize red phosphorus by coating phosphorus particles to block moisture, this method has its own limitations, and is used in high-quality materials with extremely strict requirements for moisture resistance and corrosion resistance. The current situation is that it cannot reach the level of performance of resins for electronic parts.

For this reason, l! of impregnated casting resin for high voltage electronic parts! For L flame retardants, halogen-based flame retardants, which are said to have better moisture resistance and corrosion resistance than red phosphorus-based flame retardants, and combinations of halogen-based flame retardants and antimony dioxide have been used in some cases. Flame retardants not only have the fatal drawback of emitting toxic gas when burned, but also have problems such as having a large effect on the electrical properties of the resin due to the large amount required, and being expensive, which increases the cost of the product. There is. On the other hand, red phosphorus flame retardants do not cause any problems during combustion, and can achieve extremely high flame retardant effects even when added in small amounts, so they have almost no effect on the physical properties of the resin.
In addition, since they are economically superior, there is a strong demand for improving the moisture resistance and corrosion resistance of red phosphorus flame retardants.

In view of this situation regarding red phosphorus-based flammability agents, the inventors
While conducting intensive research on improving the moisture resistance and corrosion resistance of red phosphorus flame retardants, we realized that there are limits to the conventional stabilization of red phosphorus through surface modification, so we decided to try to solve the problem from a different angle. I searched for a way. As a result, red phosphorus, which is obtained by a non-conventional biliary method and has a specific shape with particle surface conditions and physical properties that are completely different from conventional products, is extremely stable and can not only be used as a flame retardant in itself. Furthermore, the present invention was completed by discovering that the problems associated with the moisture resistance and corrosion resistance of red phosphorus flame retardants can be completely solved by subjecting such red phosphorus to surface modification treatment.

<Structure of the Invention> The present invention provides spherical red phosphorus, which is fine particles without crushed surfaces or aggregates thereof, which are obtained directly by a yellow phosphorus conversion treatment method that does not require a crushing process, and which is made into a thermosetting resin. as well as(
or) Red phosphorus flame retardants coated with aluminum hydroxide or zinc hydroxide, and thermosetting resin compositions containing the same.

Red phosphorus is usually produced by heat-treating yellow phosphorus for several days in a reaction vessel called a conversion kettle. Obtained as an object. In order for red phosphorus to exhibit flame retardant effects in synthetic resins, it must be in a fine powder form, and therefore, a pulverization process is essential for ordinary red phosphorus obtained as a lump from a conversion kettle. It is something. On the other hand, the red phosphorus used in the present invention is obtained by a different conversion process and is directly obtained as Wi granules without going through a pulverization process, and is lighter and has a smaller smoke specific gravity than conventional pulverized products. It is a fixed form.

Such light amorphous red phosphorus itself has high stability, but when it is further coated with thermosetting resin and/or aluminum hydroxide or zinc hydroxide, it is extremely stable and does not react well to water. Its properties are almost negligible compared to those coated with conventional crushed red phosphorus.
The moisture resistance and corrosion resistance of a thermosetting resin blended with this as a fire retardant are significantly improved over conventional products. The unique stability of the red phosphorus flame retardant obtained from such light amorphous red phosphorus is thought to be due to the fact that the surface state of the raw material red phosphorus particles is completely different from that of conventional products.

In other words, in the case of conventional red phosphorus, which is obtained by crushing solidly agglomerated lumps, the particle surface is composed of sharp ridges and fractured surfaces, forming a complex multi-ridged body. On the other hand, since the light amorphous red phosphorus of the present invention does not go through a crushing process, it has almost no crushed surfaces or ridge lines, and it can be seen by electron microscopy that it is a particle with a spherical surface composed of fine particles or aggregates thereof. Confirmed by ma.

For this reason, crushed red phosphorus particles have many active sites on the crushed surface, easily adsorb moisture and oxygen, and actively react with these molecules, whereas spherical particles that do not go through the crushing process It is thought that there are almost no active sites, the surface is extremely stable, and no moisture adsorption or reaction occurs. In addition, even when coated with thermosetting resin or aluminum hydroxide, the coating of crushed red phosphorus is uneven due to its surface condition and exposed crushed surfaces tend to remain.On the other hand, with spherical particles, the coating is uniform and complete. It is presumed that this makes a decisive difference in the moisture resistance stability of the coated red phosphorus.

Because spherical red phosphorus has such an extremely stable surface, it can be used without coating for applications where the requirements for moisture and corrosion resistance are relatively complex.

Even when used as a flame retardant as is, it shows no inferiority in performance compared to coated red phosphorus made from conventional pulverized red phosphorus (see Table 1).
For applications with strict requirements regarding corrosion resistance, it is desirable to perform a coating treatment with thermosetting resin, aluminum hydroxide, etc. This will almost eliminate the effect of adding red phosphorus flame retardants, and will almost completely eliminate the effects of red phosphorus flame retardants. It can provide excellent moisture resistance and corrosion resistance. Further, it is preferable to carry out a coating treatment from the viewpoint of increasing compatibility with the resin and improving workability.

The spherical red phosphorus used in the present invention can be produced, for example, by the following method.

That is, in a closed container purged with an inert gas, yellow phosphorus is heated to a temperature close to its boiling point to start the conversion reaction of red phosphorus, and when the red phosphorus nuclei have grown to the desired particle size, the reaction is stopped. When the process is stopped and unconverted yellow phosphorus is distilled off, relatively light amorphous red phosphorus in the form of microsphere-like particles that does not require any pulverization is obtained. At this time, the conversion rate and the particle size of the red phosphorus particles can be adjusted to 51ffi depending on the reaction time and reaction temperature.1 The conditions for producing red phosphorus suitable for the purpose of the present invention include a reaction temperature of 250°C to 600°C and a conversion rate of 70°C. If the reaction temperature is less than 250°C, the conversion rate will be slow, which is impractical; if it is more than 600°C, it will be difficult to control the conversion reaction, and the properties of the product will not be uniform and the shape will change. Otherwise, it will not be possible to obtain something that meets the purpose of the present invention. Also, the conversion rate is 7
If it exceeds 0%, the produced red phosphorus will become agglomerated and cannot be used as a flame retardant without going through a crushing process, making it impossible to achieve the object of the present invention.

Generally, the longer the reaction time and the higher the reaction temperature, the higher the conversion rate and the smaller the particle size. For example, a reaction at 280° C. for 4 hours produces particles with a conversion rate of 40% and an average particle size of 50°. or,
The particle size of the red phosphorus obtained in this way has a very narrow distribution and extremely high uniformity compared to ordinary pulverized products.As a result, even if the average particle size is the same, the porosity is high and the relative Generally, light buckwheat with low specific gravity can be obtained.

The red phosphorus for use as a retardant of the present invention preferably has an average particle diameter of 1 to 20 microns.

Spherical red phosphorus can also be produced by a gas phase conversion method in which yellow phosphorus vapor is heated in an active gas, a molten salt method, etc. In the present invention, spherical red phosphorus is produced by aluminum hydroxide. Or coating with zinc hydroxide is an aqueous solution of water-soluble salts of aluminum or zinc, such as aluminum sulfate, aluminum chloride, zinc sulfate, zinc chloride, etc. Red phosphorous water:! ! After addition to the suspension, aluminum hydroxide or zinc hydroxide is adsorbed onto red phosphorus particles by neutralization with sodium hydroxide or double decomposition with ChongChang charcoal, ammonium.

At this time, an aqueous suspension of red phosphorus contains 10 to 100 parts by weight of red phosphorus per 100 parts by weight of water, an aqueous solution of water-soluble salts of aluminum or 6(t), 5 to 30% of hydroxide, 1'
The amount of Ii produced is preferably 1 to 30 parts by weight per 100 parts by weight of red phosphorus, and an excellent red phosphorus flame retardant can be obtained, but the present invention is not particularly limited by this.

In the present invention, the thermosetting resin used for coating the spherical red phosphorus is one in which the synthetic raw material of the resin or its dino-stage condensate readily undergoes a polymerization reaction in an aqueous suspension of red phosphorus, or the thermosetting resin is Any resin raw material may be used as long as the condensate is emulsified and dispersed in water and uniformly washed and coated on the red phosphorus particle surface, but usually phenol/formalin, urea/formalin, melamine/formalin, Selected from furfuryl alcohol/formalin type, aniline/formalin type, polyhydric alcohol/polybasic acid type, etc. Among the above resin groups, furfuryl alcohol/formalin series, aniline/formalin series, polyhydric alcohol/polybasic acid series, etc. are difficult to polymerize in the presence of a large amount of water, so initial condensation products of resin raw materials are used. It is preferable to prepare it in advance and add it to an aqueous suspension of red phosphorus.

The resin coating treatment conditions vary somewhat depending on the type of thermosetting resin used, but a red phosphorus aqueous suspension containing 10 to 100 parts by weight of red phosphorus per 100 parts by weight of water is mixed with a synthetic raw material or initial stage of the resin. 1 of the condensate per 100 parts by weight of red phosphorus
Add ~35 parts by weight, and add 4 if synthetic raw materials for resin are used.
Stirring treatment is carried out at 0 to 100°C for 1 to 3 hours, or if a prefabricated initial compound is used, stirring is performed at 60 to 100°C for 1 to 2 hours. Fillers such as aluminum, magnesium hydroxide or titanium hydroxide can be present. Addition of a filler increases the mechanical strength of the resin coating and has the effect of hiding the purple-red color characteristic of red phosphorus, which can contribute to expanding the uses of red phosphorus flame retardants. The amount of filler added is red phosphorus 10
If the product is separated, washed with water, and dried at 130-140°C to complete the polymerization reaction, a red phosphorus flame retardant with extremely good moisture resistance and corrosion resistance can be obtained. .

In addition, if aluminum hydroxide or zinc hydroxide is adsorbed on red phosphorus particles before coating with thermosetting resin, the moisture resistance and corrosion resistance of red phosphorus will further improve. In this resin composition, the addition of the red phosphorus flame retardant shows almost no effect over a long period of time. Pretreatment with aluminum hydroxide or zinc hydroxide is carried out using aluminum or zinc sulfate or chloride in a suspension of red phosphorus containing 5 to 100 parts by weight of red phosphorus in 100 parts by weight of water. Aluminum hydroxide or zinc hydroxide is produced by a neutralization reaction between a water-soluble compound and a caustic alkali, or by a double decomposition reaction with ammonium bicarbonate, and is adsorbed onto red phosphorus particles.

The aluminum salt or zinc salt added is preferably in an amount necessary to produce 0.1 to 30 parts by weight of hydroxide based on 100 parts by weight of red phosphorus.

As shown in Table 2, the red phosphorus flame retardant of the present invention has extremely high humidity stability, and almost no generation of phosphine or corrosive acid substances, which are thought to be caused by adsorption of water molecules.
Therefore, since the resin composition does not deteriorate due to deterioration of the red phosphorus flame retardant, it is optimal as a flame retardant for thermosetting resins for high-voltage electronic components that require a high degree of quality stability.

The present invention also aims to provide a thermosetting resin composition containing this highly stable red phosphorus-based retardant. It is characterized by containing ~40 parts by weight of S, 5 to 150 parts by weight of aluminum hydroxide as a filler and flame retardant auxiliary agent, 20 to 90 parts by weight of an acid anhydride curing agent, and a curing accelerator. In the present invention, the term epoxy resin refers to any aromatic, alicyclic, or aliphatic epoxide having one or more nipoxy groups in the molecule, but it is particularly suitable for impregnating and casting electronic parts because it is liquid at room temperature. For example, bisphenol A diglycidyl ether, bisphenol F diglycidyl ether, and polyglycidyl esters of polycarboxylic acids such as phthalic acid and terephthalic acid are suitable.

If aluminum hydroxide is added in a large amount, the viscosity of the resin liquid will increase, which will hinder the casting impregnation work, and if it is too small, the flame retardant effect will be insufficient, so 5 parts per 100 parts by weight of epoxy resin
The blending amount of the red phosphorus flame retardant is preferably 150 parts by weight, considering the flame retardant effect and the influence on the viscosity of the resin.
It is preferable to use 5 to 40 parts by weight per 0 parts by weight.

Acid anhydrides are most suitable as hardening agents, such as phthalic anhydride,! #, hydrated tetrahydrophthalic acid, succinic anhydride, and other known compounds can be used. or.

2-phenylimidazole is used as a curing accelerator.

Imidazole derivatives such as 2-ethyl-4-methylimidazole are preferred from the viewpoint of M points such as workability.

The flame-retardant, corrosion-resistant, and electrical properties of the resin obtained by thoroughly kneading the wall-flammable epoxy resin composition of the present invention and curing it at 60°C for 4 hours and at 105°C for 7 hours were compared with those of conventional red phosphorus. Table 3 shows examples and comparative examples of resin compositions compared with the measured values of epoxy resin compositions containing red phosphorus flame retardants made from .

The cured resins obtained from the respective resin compositions shown in Table 4 are far superior to conventional products.

It is clear that the effect of adding a flame retardant is extremely small, and therefore the flame retardant resin composition of the present invention has a remarkable effect on improving the durability and reliability of high-voltage electronic components.

<Examples> Example 1 500 g of spherical red phosphorus was suspended in 800 g of water, 300 g of a 10% aqueous aluminum sulfate solution was added, and 100 g of a 5% aqueous sodium hydroxide solution was added dropwise with thorough stirring.

Heat to 50°C and hold for 30 minutes. This was filtered, washed with water, and dried at 120°C to obtain 516 g of coated red phosphorus.

Example 2 Suspend 500g of spherical red phosphorus in 800ml of water, add 20% aluminum chloride aqueous solution, and add 20% ammonium bicarbonate aqueous solution 400ml with sufficient stirring.
The mixture is heated to 50°C and aged for 30 minutes.

After cooling, it was filtered, washed with water, and dried at 120°C to obtain 536 g of coated red phosphorus.

Example 3 500 g of spherical red phosphorus was suspended in 800 g of water, 300 d of 20% zinc chloride aqueous solution was added, and after thorough stirring, 10%
Add 400 mQ of sodium hydroxide aqueous solution and cool at 50°C.
Heat to and mature for 30 minutes.

After cooling, filter, wash with water, and dry at 120°C to obtain coated red phosphorus 5.
40g was obtained.

Example 4 500 g of spherical red phosphorus is suspended in 1,000 InQ of water, 15 g of phenol and 27 g of 37% formalin are added, heated to 80° C., and 10 g of 85% phosphoric acid is added while stirring. After heating and stirring at the same temperature for 1 hour, the mixture was allowed to cool, filtered, and washed with water.

Dry the filter sieve at 140℃ for 3 hours to obtain 523g of coated red phosphorus.
I got it.

Example 5 500 g of spherical red phosphorus was suspended in 750 g of water, and urea 1
0g.

Add 20g of 37% formalin and heat to 90°C while stirring.

Add another 10 g of 85% phosphoric acid. After continuing heating and stirring for 2 hours, the mixture was left to stand day and night, filtered, and washed with water.

It was dried at 140°C for 31 hours to obtain 514 g of coated red phosphorus.

Example 6 A viscous precondensate obtained by reacting a mixture of 27 g of furfuryl alcohol, 3 mA of water and 0.5 g of 85% phosphoric acid on a boiling water bath for 5 hours with 10 g of 37% formalin.
is added under vigorous stirring to a solution consisting of 500 g of spherical red phosphorus and 80 g of water and heated to 90°C.

After heating and stirring for 1 hour, the mixture was filtered, washed with water, and dried at 130° C. for 3 hours to obtain 525 g of coated red phosphorus.

Example 7 6 g of melamine, 28 g of 37% formalin, and 10 g of sodium carbonate were added to a suspension consisting of 500 g of spherical red phosphorus, 50 g of magnesium hydroxide, and 750 d of water, and the mixture was heated at 90°C.
Stir and react for 2 hours. - After cooling day and night, it was filtered, washed with water, and dried at 135°C for 3 hours to obtain 555 g of coated red phosphorus.

Example 8 4.3 g of 98% glycerin, 2.5 g of anhydrous phthalic acid M and 15 g of flaxseed oil fat fi were mixed and heated to 2.0 g while passing carbon dioxide gas.
After heating to 00 to 230°C, add 3.3 g of phthalic anhydride, raise the temperature to 245°C, and cool when the acid value reaches 12 to 15.
Add 2 - of and disperse in 100 - of water. This emulsified dispersion was mixed with an S suspension consisting of 750 g of water, 50 g of spherical red phosphorus, and 50 g of aluminum hydroxide, and heated and stirred at 90° C. for 1 hour. After cooling, filter and wash with water at 140'C.
After drying for 4 hours, 573 g of coated red phosphorus was obtained.

Example 9 250 g of spherical red phosphorus was suspended in 50° of water, and 8%
Add 40% of aqueous aluminum sulfate solution and stir thoroughly.

5% sodium hydroxide solution was added dropwise to this, and 50% sodium hydroxide solution was added dropwise.
Add to ℃ and hold for 10 minutes. Next, 8 g of phenol and 15 g of 37% formalin were added, heated at 80'C for 1 hour, stirred, allowed to cool, filtered, washed with water, and heated to 80'C.
Dry 1 ul at 3 o'clock. 270 g of coated red phosphorus was obtained.

Example 10 8% aluminum sulfate aqueous solution 40- was added to a suspension (consisting of spherical red phosphorus 250 and Bo 5oo-), and after stirring, 15% ammonium bicarbonate aqueous solution 45M1 was added dropwise to the suspension.
Aging for 20 minutes at °C. Adjust the pH to 10.0 with ammonia water
After adjusting, please do it in advance! A 12.5% reso-7 type phenolic prepolymer (phenol/formalin 21
72 mol) loog and 25 g of ammonium chloride are added and stirred at 50° C. for 30 minutes. After cooling, filter, wash with water, and dry at 120°C for 1:1 + jj to obtain 264 g of coated red phosphorus.
I got it.

Example 11 To a suspension consisting of spherical red phosphorus and 900 d of water, 80 d of an 8% zinc sulfate aqueous solution was added and stirred, and then clarified with 100 mQ of a 15% ammonium bicarbonate aqueous solution and heated at 60°C.
Heat for 20 minutes. A reaction mixture of 26 g of acetone and 42 g of 37% formalin to an acentone-formalin initial condensate was added thereto, and the mixture was heated at 65° C. for 30 minutes with stirring. After cooling, filter and wash with water, and incubate at 130°C.
After drying for hours, 572 g of coated red phosphorus was obtained.

Example 12 165ml of 10% aluminum sulfate aqueous solution was added to a suspension consisting of spherical red phosphorus soo grams and 750ml of water, and after stirring, 100aQ of 15% ammonium bicarbonate aqueous solution was added dropwise and heated at 60°C for 20 minutes. 1. Next, a suspension consisting of 30 g of titanium hydroxide and 30 mQ of water and 2
Add 6g of 37% formalin, adjust the pH to 7.5 with aqueous ammonia, and continue stirring at 90°C for 2 hours.

- Leave to cool day and night, filter and wash with water, dry at 135℃ for 3 hours,
518 g of coated red phosphorus was obtained.

Table 1 Comparison of physical property values of red phosphorus Stabilized crushed red phosphorus (1) Pulverized red phosphorus treated in the same manner as in Example 4 Stabilized crushed red phosphorus (2) Pulverized red phosphorus treated in the same manner as in Example 9 Things dl! Take the log of the sample in a standard method specific gravity specific volume tester (manufactured by Ishiyama Scientific Instruments Co., Ltd., capacity #, 20 mQ) and shake it 100 times to measure the amount of phosphine generated. Shake the water thoroughly, seal it tightly, and leave it for 24 hours. Measure the phosphine in the space. 5 g of P2O5 sample was dissolved in 100 mQ of water,
After being left at 21°C and 2.2 atm for 100 hours, it was filtered to remove p2o from the filtrate.

Measure the content Table 2 Red phosphorus flame retardant based on spherical red phosphorus (Example 1
- 12) Stability measurement methods are all according to Table 1 Comparative Example 1 Pulverized red phosphorus was treated in the same manner as in Example 1 2 Pulverized red phosphorus was treated in the same manner as in Example 4 JT 3 Pulverized Red phosphorus treated in the same manner as in Example 5 4 Pulverized red phosphorus treated in the same manner as in Example 9 5 Pulverized red phosphorus treated in the same manner as in Example 10 6 Pulverized red phosphorus in Example Table 3: Resin composition examples (component blending amounts) The numbers in parentheses indicate Example No. 11. The numbers represent heavy indigo parts.

The red phosphorus in the comparative example is as follows: 1, untreated spherical red phosphorus 2, crushed red phosphorus treated in the same manner as in Example 1 (3), crushed red phosphorus treated in the same manner as in Example 4 (4) , pulverized red phosphorus treated in the same manner as in Example 6 5, crushed red phosphorus treated in the same manner as in Example 10 Table 4 Method for measuring physical properties and electrical properties of cured resin Flame retardancy JISK-5911it flammability test B Hochu moisture (water absorption rate) Based on JISK-6911 boiling water absorption test. However, the conditions of the subchamber are 121℃, 2 atm, 100%
RH, 100 hours.

Corrosion: A certain amount of resin composition is applied to a copper plate with a certain surface area and cured for 20 minutes in an air bath at 140°C and 80% RH.
After standing for 0 hours, the resin layer is peeled off. Place a 1 m square piece of transparent graph paper on the surface of the peeled heel and count the number of discolorations within 1 d (1 m" x 100 pieces).

Dielectric constant and dielectric loss tangent According to JISK-6911: JI electric constant and dielectric loss tangent measurement method.

Procedural Amendment Form September 13, 1982 2. Name of the Invention: Red Phosphorous B Fuel Agent and Company U Fuel Resin Composition 3. Notes on Person Making the Amendment 11h Address of Patent Issuer: Tokominato, Toyama Prefecture 34-5, Ichizanbori, Number of inventions increased by amendment None 6, Subject of amendment
Circulation of the claims and detailed description of the invention in the specification 7? Ill Correct Contents (1) The claims of the specification are corrected as shown in the attached sheet. (2) Specification W, page 7, line 61, Qi, line 9. The fracture surface and fI
The red phosphorus, which is composed of one microparticle or a collection of particles and has a spherical surface, has a spherical surface. , the fracture surfaces and ridge lines are mostly composed of microparticles with bilobed and continuous surfaces.

(3) "Global-like cryo" on page 7, line 14 and line 19 of the specification will be corrected to "spherical-like red phosphorus."

(4) Details g! ! Page 8, line 21, ``No crushing required'' is corrected to ``Almost no crushing required.''

(5) In the specification, page 8, line 21 - page 9, line 1, "one microsphere shape" is corrected to "fine particle shape".

(6) Insert the following sentence between lines 20 and 21 on page 9 of the statement.

``As the conversion rate increases, more particles of red phosphorus are formed as aggregates, but the cohesiveness of the aggregates is weak, they crumble, and are called pulverization (processing with I is not necessary).・No. However, if it is necessary to adjust the aperture depending on the application, it is an idle mechanical process; for the purpose of the present invention, it is not a problem to do so. The fracture surface that occurs as the body collapses has almost no effect on the stability of red phosphorus.Even though it is fractured, it is physically close to a spherical surface, and is a solid lump. The stability of the 19 surface, which is different from the fracture surface formed by crushing, is as good as that of a spherical surface and is, so to speak, a collapse surface.Therefore, in the present invention, a surface with this irregular collapse surface is also referred to as a sphere t1: In the following explanation, these aggregates will also be referred to as spherical red phosphorus.

(7) Specification M, page 11, item 211, ``Hatsu ■ condensation thing'' is corrected to ``Hatsuho condensation thing''.

(8) Insert the following sentence between lines 14 and 15 on page 15 of the statement.

"Example of production of spherical red phosphorus" 500g of yellow phosphorus was placed in a stainless steel container purged with nitrogen gas, heated to 270'C for 4 hours, and then rotated 1
Removes yellow phosphorus. 211 g of fluid fine granular red phosphorus with an average particle size of 50 mm/m was obtained.

Production Example of Spherical Red Phosphorus 2 100 g of yellow phosphorus is placed in a high-pressure reaction vessel purged with nitrogen gas, tightly sealed, heated to 480°C in 30 minutes, maintained at that temperature for 10 minutes, and cooled. Remove unconverted yellow phosphorus 68
g of finely divided red phosphorus was obtained. In the 100mesh sieve test, the residue was 22z, but by hand-polishing it, it became a loomesh. ” (9) Ming wi
tPage 21, replace Table 1 with the following table and insert the following explanation below the table.

・Redness, physical properties n7-specific gravity and fi2 generation amount 1
Ignition temperature i elution P = 0 = 1□ sphere turbulence red 1 le 2
・0.411 io, + 141 j
38.2 □.

Bulk specific gravity unit g/(-H4 Spherical redness, 1 Production example) Bead-like redness Spherical-like redness, 2 Production Yuj2 Spherical-like redness Separate
Paper 2, Claims (1) A method for converting yellow phosphorus that does not require crushing; spherical red phosphorus without crushed surfaces and/or aggregates thereof that can be obtained directly from this are used as flame retardant components. Red phosphorus flame retardant (2)
Spheroidal red phosphorus and/or its aggregates were mixed with yellow phosphorus at 250'C-600' in a reaction vessel purged with inert gas.
The red phosphorus flame retardant according to claim 1, which is red phosphorus heated to 1T and converted at a conversion rate of 7 o
3) The red phosphorus flame retardant according to claim 1, wherein the spherical red phosphorus and/or the aggregate thereof are coated with a thermosetting resin (4) The spherical red phosphorus and/or the aggregate thereof body is hydroxyl 1
The red phosphorus flame retardant (5) according to claim 1, which is coated with hyaluminum or zinc hydroxide, wherein the spherical red phosphorus and/or its aggregates are coated with aluminum hydroxide and/or zinc hydroxide. The red phosphorus flame retardant (6) according to claim 1, which is double coated with a thermosetting resin. i'I'l Arsenic Pi fat coating is made from aluminum hydroxide, magnesium hydroxide, and monohytitanium hydroxide! ! Red phosphorus flame retardant (7) 100 parts by weight of epoxy resin as described in Claims 3 and 5, Claim 1 - A flame-retardant resin composition comprising 5 to 40 parts by weight of the red phosphorus flame retardant described in item 6, 5 to 150 parts by weight of aluminum hydroxide, and a hardening agent and a hardening agent.

Claims (7)

[Claims] (1) A red phosphorus flame retardant whose flame retardant component is spherical red phosphorus without crushed surfaces, which is directly obtained by a yellow phosphorus conversion process that does not require pulverization. (2) The spherical red phosphorus is red phosphorus obtained by heating yellow phosphorus to 250°C to 600°C in a reaction vessel purged with inert gas and converting it at a conversion rate of 70% or less. 1
Red phosphorus flame retardant as described in section. (3) The red phosphorus flame retardant according to claim 1, wherein spherical red phosphorus without a fracture surface is coated with a thermosetting resin. (4) The red phosphorus flame retardant according to claim 1, wherein the spherical red phosphorus without fractured surfaces is coated with aluminum hydroxide or zinc hydroxide. (5) The red phosphorus flame retardant according to claim 1, wherein spherical red phosphorus without a fracture surface is double coated with aluminum hydroxide or (and) zinc hydroxide, and a thermosetting resin. . (6) The thermosetting resin coating is aluminum hydroxide,
1 selected from magnesium hydroxide and titanium hydroxide
The red phosphorus flame retardant according to claims 3 and 5, which is carried out in the presence of a species or two or more compounds. (7) 100 parts by weight of epoxy resin, Claim 1
A flame-retardant resin composition comprising 5 to 40 parts by weight of the red phosphorus flame retardant described in Items to 6 and 5 to 150 parts by weight of aluminum hydroxide, and a curing agent and a curing accelerator.