JP6522907B2 - Pentaerythritol diphosphonate and method for producing the same - Google Patents

Description

  The present invention relates to a pentaerythritol diphosphonate compound having a specific structure and a method for producing the same. More particularly, the present invention relates to pentaerythritol diphosphonate which can be used as an additive for flame retardants, nucleating agents, plasticizers and the like, and which is particularly effective as a flameproofing agent for fibers, and a method for producing the same.

In recent years, many fibers are used for interior materials and filter materials for automobiles, aircraft, railways, buildings, etc. The types of fiber materials are also synthetic fibers such as polyester, nylon, acrylonitrile, polypropylene, rayon, cotton, Cellulosic fibers such as hemp or animal fibers such as wool, silk and feathers are used alone or in combination.
Since the textile products using these have the fault of being easy to burn, flameproof performance is required. For example, in some applications such as uniforms for aircraft pilots, although flame retardant fibers are used as raw materials, post-processing flame retarding is generally performed in terms of cost.

  Typical examples of post-processing flameproofing are a method of directly attaching a flameproofing agent to a fiber product, and a method of adding a flameproofing agent to various synthetic fiber binders and adhering them as a flameproof binder. It is generally used for upholstery sheets such as cars, or backing processing such as carpets. Particularly in the latter flameproofing method, not only the flameproofing of the fibers but also flameproofing of the synthetic resin binder used in combination is required.

  Conventionally, a combination formulation of a halogen-based compound or a halogen-based compound and antimony oxide has been performed as a flame retardant. However, in recent years, from the point of environmental protection and the harmfulness of the generated gas at the time of combustion, there is an increasing demand for flameproofing without using a halogen flameproofing agent. As non-halogen flame retardants, many flame retardants are known such as ammonium phosphate, ammonium sulfamate, ammonium sulfate, borax, boric acid, aluminum hydroxide, magnesium hydroxide, phosphoric acid ester and the like.

  However, when the amount necessary for producing a flameproofing effect is added, the water-soluble flameproofing agent causes thickening or breaking (gumming up) of the synthetic resin emulsion, lowering the film strength of the resin, lowering the heat resistance, There is a problem such as deterioration of texture. In addition, since ammonium phosphate which is non-halogen and relatively flameproof effective has solubility in water, elution to water occurs under the condition that water resistance is required, and the physical property of the product, flameproof There is a problem with Furthermore, even the ammonium polyphosphate encapsulated with the improved resin etc. does not have sufficient water resistance. For this reason, a flameproofing method having sufficient flameproofness and various physical properties has not been provided without using a halogen flameproofing agent, and therefore development has been sought (patent documents 1 to 3). .

On the other hand, di-substituted pentaerythritol diphosphonates have been variously studied focusing on flame retardants for resins. By blending this compound into a thermoplastic resin, it is possible to achieve flame retardancy of the thermoplastic resin. The thermoplastic resin composition in which the phosphonate compound is compounded does not deteriorate the properties such as heat resistance and impact resistance due to the compounding of the flame retardant, and the compound volatilizes during kneading, or in the resin due to bleeding or the like. Have features that will not be lost.
Several methods for producing the above disubstituted pentaerythritol diphosphonate are disclosed. Patent Document 4 describes a preparation example in which diphenylpentaerythritol diphosphonate is obtained by the reaction of pentaerythritol and phenylphosphonic acid dichloride.

Patent Document 5 discloses a method of reacting dibenzyl pentaerythritol diphosphate with benzyl bromide to obtain dibenzyl pentaerythritol diphosphonate by Arbuzov rearrangement.
Patent Document 6 discloses a method for obtaining dialkylpentaerythritol diphosphonate by Arbuzov rearrangement by reacting dialkylpentaerythritol diphosphite with benzyl chloride or benzyl bromide in the presence or absence of a solvent.
In Patent Documents 7 and 8, Arbuzov transfer reaction is effected by heating a dialkylpentaerythritol diphosphite in the presence of an alkyl halide catalyst or a bromide or iodide catalyst of an alkali metal or alkaline earth metal to give a dialkylpentaerythritol A method of obtaining a diphosphonate is disclosed.

In addition, Patent Document 9 discloses a method for producing pentaerythritol diphosphonate through three steps of reaction using phosphorus trichloride and pentaerythritol as a starting material, and describes a method which can be recovered in high yield. .
However, even in the above-mentioned patent documents, sufficient studies on the actual scale have not been made, and further reduction of impurities and improvement in purity are required, and further, particle characteristics suitable for use as a flameproofing agent for fibers There has been a need for pentaerythritol diphosphonates having

JP 10-212669 A Unexamined-Japanese-Patent No. 2002-220782 Patent No. 3484490 JP 05-163288 A WO 2002/092690 pamphlet U.S. Pat. No. 4,174,343 U.S. Pat. No. 3,141,032 Japanese Patent Application Laid-Open No. 54-157156 Patent No. 4181127

  The object of the present invention is to obtain an industrially advantageous method of excellent productivity and, when used as a flameproofing agent for fibers, it is possible to impart high flameproofness and good physical properties. An erythritol diphosphonate and a method for producing the same.

As a result of intensive studies, the inventors of the present invention have found that pentaerythritol diphosphonate obtained by a specific production method imparts high flame resistance and good physical properties when used as a flameproofing agent for fibers. The present invention has been completed.
That is, according to the present invention, the object of the invention is achieved by the following.

（式中、Ａｒ^１およびＡｒ^２は、同一または異なっていてもよく、炭素数６〜２０の置換もしくは非置換のアリール基である。また、Ｒ^３、Ｒ^４、Ｒ^５およびＲ^６は、それぞれ同一または異なっていてもよく、水素原子、炭素数６〜２０の置換もしくは非置換のアリール基、または炭素数１〜２０の飽和もしくは不飽和の直鎖もしくは分岐のアルキル基である。）

（式中、Ａｒ^３は炭素数６〜２０の置換もしくは非置換のアリール基である。また、Ｒ^７およびＲ^８は、同一または異なっていてもよく、水素原子、または炭素数１〜２０の飽和もしくは不飽和の直鎖もしくは分岐のアルキル基である。ＸはＢｒ基である。）
２．前記式（１）で示されるペンタエリスリトールジホスホネートの（ｉ）体積基準メジアン径が２０μｍ以下であり、（ｉｉ）純度が９９％以上であり、（ｉｉｉ）前記式（２）に示されるハロゲン化化合物の含有量が１５０ｐｐｍ以下である前項１記載のペンタエリスリトールジホスホネート。
３．前記式（１）で示されるペンタエリスリトールジホスホネートが下記式（１−ａ）で示されるジベンジルペンタエリスリトールジホスホネートである前項１記載のペンタエリスリトールジホスホネート。

1. Pentaerythritol diphosphonate represented by the following formula (1), wherein (i) the volume standard median diameter is 22 μm or less, (ii) the purity is 98% or more, and (iii) to the following formula (2) Pentaerythritol diphosphonate characterized in that the content of the halogenated compound shown is 200 ppm or less.

(Wherein, Ar ¹ and Ar ² may be the same or different and each is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ³ , R ⁴ , R ⁵ and R ⁶ are And each may be the same or different, and is a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms.)

(Wherein, Ar ³ is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ⁷ and R ⁸ may be the same or different, and are hydrogen atoms or 1 to 20 carbon atoms. A saturated or unsaturated linear or branched alkyl group, and X is a Br group.)
2. The (i) volume-based median diameter of the pentaerythritol diphosphonate represented by the formula (1) is 20 μm or less, (ii) the purity is 99% or more, and (iii) the halogen represented by the formula (2) 5. The pentaerythritol diphosphonate according to the above 1, wherein the content of the at least one compound is 150 ppm or less.
3. 5. The pentaerythritol diphosphonate as described in the above 1, wherein the pentaerythritol diphosphonate represented by the formula (1) is a dibenzylpentaerythritol diphosphonate represented by the following formula (1-a).

（式中、Ａｒは、炭素数６〜２０の置換もしくは非置換のアリール基である。また、Ｒ^１およびＲ^２は、同一または異なっていてもよく、水素原子、炭素数６〜２０の置換もしくは非置換のアリール基、または炭素数１〜２０の飽和もしくは不飽和の直鎖もしくは分岐のアルキル基である。）

（式中、Ａｒ^１およびＡｒ^２は、同一または異なっていてもよく、炭素数６〜２０の置換もしくは非置換のアリール基である。また、Ｒ^３、Ｒ^４、Ｒ^５およびＲ^６は、それぞれ同一または異なっていてもよく、水素原子、炭素数６〜２０の置換もしくは非置換のアリール基、または炭素数１〜２０の飽和もしくは不飽和の直鎖もしくは分岐のアルキル基である。）

（式中、Ａｒ^３は炭素数６〜２０の置換もしくは非置換のアリール基である。また、Ｒ^７およびＲ^８は、同一または異なっていてもよく、水素原子、または炭素数１〜２０の飽和もしくは不飽和の直鎖もしくは分岐のアルキル基である。ＸはＢｒ基である。）

（式中、Ａｒ^１およびＡｒ^２は、同一または異なっていてもよく、炭素数６〜２０の置換もしくは非置換のアリール基である。また、Ｒ^３、Ｒ^４、Ｒ^５およびＲ^６は、それぞれ同一または異なっていてもよく、水素原子、炭素数６〜２０の置換もしくは非置換のアリール基、または炭素数１〜２０の飽和もしくは不飽和の直鎖もしくは分岐のアルキル基である。） 4. (A) Phosphorous trichloride is added dropwise to the pentaerythritol at a dropping rate of 0.50 to 2.00 (mol / (hr · mol)) while phosphorus trichloride and pentaerythritol are in the presence of an inert solvent To give pentaerythritol dichloro phosphite represented by the formula (3) (a reaction), (B) the pentaerythritol dichloro phosphite is reacted with the aralkyl alcohol represented by the formula (4) to obtain a formula 5) to obtain pentaerythritol diphosphite (reaction b), (C) the pentaerythritol diphosphite in the presence of the halogenated compound represented by the formula (2), at a temperature of 80 ° C. to 300 ° C. Heat treatment under conditions to obtain crude crystals of pentaerythritol diphosphonate (reaction c), (D) washing temperature 3 under conditions satisfying the following formula (I) Perform repulping washing at to 65 ° C. (washing step), (E) drying under reduced pressure or performing hot air drying (drying step) The method of producing pentaerythritol diphosphonate of formula (1), characterized in that.
(I) 10 ≦ X × Y ² ≦ 40
(Wherein, X is the washing time (h) and Y is the solubility (g / 100 g-solvent) of pentaerythritol diphosphonate in the washing solvent under the temperature conditions for washing.)

Wherein Ar is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, and R ¹ and R ² may be the same or different, and a hydrogen atom or a substitution of 6 to 20 carbon atoms Or an unsubstituted aryl group, or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms.)

(Wherein, Ar ¹ and Ar ² may be the same or different and each is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ³ , R ⁴ , R ⁵ and R ⁶ are And each may be the same or different, and is a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms.)

(Wherein, Ar ³ is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ⁷ and R ⁸ may be the same or different, and are hydrogen atoms or 1 to 20 carbon atoms. A saturated or unsaturated linear or branched alkyl group, and X is a Br group.)

(Wherein, Ar ¹ and Ar ² may be the same or different and each is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ³ , R ⁴ , R ⁵ and R ⁶ are And each may be the same or different, and is a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms.)

5. The method for producing pentaerythritol diphosphonate according to item 4, wherein the solution or suspension of pentaerythritol dichlorophosphite obtained in the reaction a) is subjected to heat treatment and / or reduced pressure treatment.
6. 5. The method for producing pentaerythritol diphosphonate according to the above 4, wherein pentaerythritol dichlorophosphite is not isolated from the solution or suspension of pentaerythritol dichlorophosphite obtained in the a reaction, and is used for the next b reaction.
7. In the a reaction, the inert solvent to be used is a solvent comprising one or more selected from the group consisting of aromatic hydrocarbon, aliphatic hydrocarbon, halogenated hydrocarbon and oxygen atom containing hydrocarbon. The manufacturing method of the pentaerythritol diphosphonate of the preceding clause 4.
8. 5. The method for producing pentaerythritol diphosphonate as described in 4 above, wherein 195 mol% to 240 mol% of phosphorus trichloride is used relative to pentaerythritol in the reaction a.
9. The method for producing pentaerythritol diphosphonate according to the above 4, wherein the a reaction is carried out in the presence of an organic base compound.
10. The method for producing pentaerythritol diphosphonate according to the above 4, wherein the reaction b is carried out in the presence of an organic base compound.
11. The method for producing pentaerythritol diphosphonate according to the above 10, wherein the organic base compound is used in an amount of 180 mol% to 400 mol% based on pentaerythritol in the reaction b.
12. The organic base compound and a salt of the organic base compound (hereinafter, referred to as an organic base compound component) are separated and removed from the reaction system from the reaction mixture containing pentaerythritol diphosphite obtained in the above b reaction, and the organic base compound 11. The method for producing pentaerythritol diphosphonate according to the above 10, wherein the component-removed pentaerythritol diphosphite is used in c reaction.
13. The manufacturing method of the pentaerythritol diphosphonate of the preceding clause 12 whose organic base compound component isolate | separated away to the exterior of the reaction system of the preceding clause 12 is 90 mol% or more with respect to 100 mol% of the used organic base compound.
14. In the preceding paragraph 12, the pentaerythritol diphosphite is used in the subsequent c reaction without isolating the pentaerythritol diphosphite from the solution or suspension of pentaerythritol diphosphite after separating and removing the organic base compound component out of the reaction system. The manufacturing method of pentaerythritol diphosphonate as described in the preceding clause 12.
15. The method for producing pentaerythritol diphosphonate as described in 4 above, wherein 180 mol% to 250 mol% of aralkyl alcohol is used with respect to pentaerythritol in the reaction b.
16. 5. The process for producing pentaerythritol diphosphonate as described in 4 above, wherein the halogenated compound used in the c reaction is benzyl bromide.
17. 5. The process for producing pentaerythritol diphosphonate as described in 4 above, wherein the halogenated compound used in the reaction c is benzyl bromide, and 1.5 to 3 moles of the benzyl bromide are used with respect to 1 mole of pentaerythritol.
18. The method for producing pentaerythritol diphosphonate according to the above 4, wherein the washing solvent used in the washing step comprises at least one solvent selected from the group consisting of methanol, ethanol, isopropyl alcohol and acetone.

２０．（ｉ）体積基準メジアン径が２２μｍ以下であり、（ｉｉ）純度が９８％以上であり、（ｉｉｉ）下記式（２）に示されるハロゲン化化合物の含有量が２００ｐｐｍ以下であることを特徴とする下記式（１）で示されるペンタエリスリトールジホスホネートを含む繊維用防炎加工剤。

（式中、Ａｒ^１およびＡｒ^２は、同一または異なっていてもよく、炭素数６〜２０の置換もしくは非置換のアリール基である。また、Ｒ^３、Ｒ^４、Ｒ^５およびＲ^６は、それぞれ同一または異なっていてもよく、水素原子、炭素数６〜２０の置換もしくは非置換のアリール基、または炭素数１〜２０の飽和もしくは不飽和の直鎖もしくは分岐のアルキル基である。）

（式中、Ａｒ^３は炭素数６〜２０の置換もしくは非置換のアリール基である。また、Ｒ^７およびＲ^８は、同一または異なっていてもよく、水素原子、または炭素数１〜２０の飽和もしくは不飽和の直鎖もしくは分岐のアルキル基である。ＸはＢｒ基である。） 19. The manufacturing method of the pentaerythritol diphosphonate of the preceding clause 4 whose pentaerythritol diphosphonate shown by said Formula (1) is the dibenzyl pentaerythritol diphosphonate shown by following formula (1-a).

20. (I) characterized in that the median diameter on a volume basis is 22 μm or less, (ii) the purity is 98% or more, and (iii) the content of the halogenated compound shown in the following formula (2) is 200 ppm or less The flameproofing agent for fibers containing the pentaerythritol diphosphonate shown by following formula (1) made into said.

(Wherein, Ar ¹ and Ar ² may be the same or different and each is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ³ , R ⁴ , R ⁵ and R ⁶ are And each may be the same or different, and is a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms.)

(Wherein, Ar ³ is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ⁷ and R ⁸ may be the same or different, and are hydrogen atoms or 1 to 20 carbon atoms. A saturated or unsaturated linear or branched alkyl group, and X is a Br group.)

  The pentaerythritol diphosphonate compound having the specific structure of the present invention exhibits an excellent effect as an additive such as a flame retardant, a crystal nucleating agent, a plasticizer and the like, and in particular, a high flame resistance as a flameproofing agent for fibers And since it can impart good physical properties, it is widely useful for applications such as flameproof fiber products, and its industrial effects are outstanding.

Hereinafter, the present invention will be described in detail.
<Pentaerythritol diphosphonate>
As the pentaerythritol diphosphonate compound of the present invention, in the above formula (1), Ar ¹ and Ar ² represent a phenyl group, various xylyl groups, various toluyl groups, di-t-butylphenyl groups, various cumenyl groups, biphenyl groups, naphthyls R ³ , R ⁴ , R ⁵ and R ^{6 each} represent a hydrogen atom, methyl group, ethyl group, various propyl groups, various butyl groups, various pentyl groups, propenyl groups, phenyl groups, various toluyl groups, various groups Compounds which are a xylyl group, various cumenyl groups, di-t-butylphenyl groups, biphenyl groups, naphthyl groups and the like are preferred. More preferably, Ar ¹ and Ar ² are a phenyl group, R ³ , R ⁴ , R ⁵ and R ⁶ are a hydrogen atom, a methyl group or a phenyl group, and particularly preferably Ar ¹ and Ar ² are a phenyl group, R ³ , R ⁴ , R ⁵ and R ⁶ are hydrogen atoms.

  Specifically, 3,9-bis (phenylmethyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis (( 2-Methylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((3-methylphenyl) methyl) -3,9-Dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((4-methylphenyl) methyl) -3,9-dioxo- 2,4,8,10-Tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((2,4-dimethylphenyl) methyl) -3,9-dioxo-2,4,8 , 10-tetraoxa 3,9-Diphosphaspiro [5.5] undecane, 3,9-bis ((2,6-dimethylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] Undecane, 3,9-bis ((3,5-dimethylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] Undecane, 3,9-bis ((2,4,6-trimethylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3 , 9-bis ((2-sec-butylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ( (4 sec-Butylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((2,4-di-sec) -Butylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((2,6-di-sec- Butylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((2,4,6-tri-sec -Butylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((2-tert-butylphenyl) methyl )- 3,9-Dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((4-tert-butylphenyl) methyl) -3,9-dioxo 2,4,8,10-Tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((2,4-di-tert-butylphenyl) methyl) -3,9-dioxo- 2,4,8,10-Tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((2,6-di-tert-butylphenyl) methyl) -3,9-dioxo-2 , 4,8,10-Tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((2,4,6-tri-tert-butylphenyl) methyl) -3,9-dioxo- 2,4,8 10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((4-biphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9- Diphosphaspiro [5.5] undecane, 3,9-bis ((1-naphthyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((2-naphthyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((1 -Anthryl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((2-anthryl) methyl) -3, 9- Oxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis ((9-anthryl) methyl) -3,9-dioxo-2,4,8, 10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis (1-phenylethyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [ 5.5] Undecane, 3,9-bis (2-methyl-2-phenylethyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis (diphenylmethyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis (triphenylmethyl)- 3,9-Dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3-phenylmethyl-9-((2,6-dimethylphenyl) methyl) -3,9 -Dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3-phenylmethyl-9-((2,4-di-tert-butylphenyl) methyl) -3, 9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3-phenylmethyl-9- (1-phenylethyl) -3,9-dioxo-2,4, 8,10-Tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3-phenylmethyl-9-diphenylmethyl-3,9-dioxo-2,4,8,10-tetraoxa-3 9-Diphosphaspiro [5.5] undecane, 3-((2,6-dimethylphenyl) methyl) -9- (1-phenylethyl) -3,9-dioxo-2,4,8,10-tetraoxa-3 , 9-diphosphaspiro [5.5] undecane, 3-((2,4-di-tert-butylphenyl) methyl) -9- (1-phenylethyl) -3,9-dioxo-2,4,8, 10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3-diphenylmethyl-9- (1-phenylethyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9- Diphosphaspiro [5.5] undecane, 3-diphenylmethyl-9-((2,6-dimethylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-dipho Phaspiro [5.5] undecane, 3-diphenylmethyl-9-((2,4-di-tert-butylphenyl) methyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9 -Diphosphaspiro [5.5] undecane is mentioned.

  Among them, 3,9-bis (phenylmethyl) -3,9-dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis (1-phenylethyl) ) -3,9-Dioxo-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane, 3,9-bis (diphenylmethyl) -3,9-dioxo-2,4, 8,10-Tetraoxa-3,9-diphosphaspiro [5.5] undecane is preferable, and 3,9-bis (phenylmethyl) -3,9-dioxo-2,4 represented by the following formula (1-a) is particularly preferable , 8, 10-tetraoxa-3, 9- diphosphaspiro [5.5] undecane (dibenzyl pentaerythritol diphosphonate) is preferred.

(Volume-based median diameter)
The volume-based median diameter of the pentaerythritol diphosphonate of the present invention is 30 μm or less, preferably 25 μm or less, more preferably 20 μm or less, and particularly preferably 15 μm or less. When the volume-based median diameter is larger than 30 μm, the color tone of the processed cloth and the resistance to chalking may be deteriorated when it is used as a flame retardant processing agent for fibers, which is not preferable. In addition, the volume-based median diameter of the pentaerythritol diphosphonate of the present invention is preferably 1 μm or more, more preferably 2 μm or more, and still more preferably 3 μm or more. When the volume-based median diameter is 1 μm or more, the handleability of the powder is good, which is preferable.

(purity)
The purity of the pentaerythritol diphosphonate of the present invention is 98% or more, preferably 99% or more, and more preferably 99.5% or more. When the purity is 98% or more, high flame resistance and good physical properties can be obtained when used as a flameproofing agent for fibers.

(Remaining amount of halogenated compound)
The residual amount of the halogenated compound represented by the formula (2) contained in the pentaerythritol diphosphonate of the present invention is 200 ppm or less, preferably 150 ppm or less, more preferably 100 ppm or less, particularly preferably 50 ppm or less. If the residual amount of the halogenated compound is higher than 200 ppm, it is not preferable because a tearing irritating odor remains. In addition, when used as a flameproofing agent for fibers, if the residual amount of the halogenated compound is higher than 200 ppm, the container or apparatus made of SUS may be corroded, which is not preferable.

<Method of producing pentaerythritol diphosphonate>
(A reaction (the first step reaction))
About Phosphorus Trichloride Purity The phosphorus trichloride used in the present invention preferably has a purity of 98% or more. The highly pure phosphorus trichloride can be obtained, for example, by distilling a commercial product under an inert atmosphere. The inert atmosphere is a state in which there is substantially no oxygen gas, moisture and the like that can modify phosphorus trichloride used in the present invention. Specifically, the oxygen gas concentration in the system is desirably 5% or less, preferably 1% or less, and more preferably 100 ppm or less. As a specific example, there is a method in which the inside of the reaction system is replaced with an inert gas such as nitrogen, argon or the like, and then distillation is performed in the inert gas flow or in the inert gas atmosphere. The oxygen concentration can be measured by a zirconia analysis method or the like specified in JIS B 7983. The purity of phosphorus trichloride can be quantified by gas chromatography, and as shown in JIS K8404-1887, quantification by chemical reaction is possible.

About Pentaerythritol-Purity, Water Content It is desirable that pentaerythritol used in the present invention has a purity of 98% or more and a water content of 1000 ppm or less. Preferably, the water content is 500 ppm or less, and more preferably, the water content is 100 ppm or less. Pentaerythritol having high purity can be obtained mainly by recrystallizing a commercial product from water to remove high molecular weight impurities. In addition, pentaerythritol having a low water content can be obtained by heating and drying immediately before it is used for the reaction. The purity of pentaerythritol is quantified by gas chromatography. The water content of pentaerythritol is quantified by Karl Fischer method.

Regarding the molar ratio of pentaerythritol and phosphorus trichloride The molar ratio of phosphorus trichloride to pentaerythritol of the present invention is preferably 195 mol% to 240 mol% of phosphorus trichloride per 100 mol% of pentaerythritol, It is more preferable to use mol%-220 mol%. If the molar ratio is less than 195 mol%, the recovery of pentaerythritol diphosphonate finally obtained may be significantly reduced. On the other hand, when the molar ratio exceeds 240% by mole, the unreacted trichloride remaining on the reaction has a large influence on the subsequent reaction, and the amount of pentaerythritol diphosphonate finally obtained may be reduced. In addition, the amount of waste may increase and productivity may drop significantly.

Solvents and Solvent Types The solvent used in the reaction of phosphorus trichloride with pentaerythritol of the present invention is an inert solvent not involved in the reaction, and includes aromatic hydrocarbons, aliphatic hydrocarbons, halogenated hydrocarbons and An inert solvent consisting of one or more selected from the group consisting of oxygen atoms and hydrocarbons is desirable. The solvents may be used alone or in combination.
Such solvent may be any inert solvent which does not react with pentaerythritol, phosphorus trichloride or an organic base compound. As such, hexane, heptane, octane, decane, dodecane, diethyl ether, dipropyl ether, dipropyl ether, dibutyl ether, tetrahydrofuran, dioxane, methylene chloride, chloroform, carbon tetrachloride, benzene, chlorobenzene, chlorobenzene, ortho-dichlorobenzene, toluene, Xylene, ethylbenzene, propylbenzene, butylbenzene and the like can be mentioned. In particular, those having a boiling point of 100 ° C. to 300 ° C. under normal pressure are suitably used. Examples thereof include decane, dodecane, dibutyl ether, dioxane, chlorobenzene, orthodichlorobenzene, toluene, xylene, ethylbenzene and the like, with xylene being particularly preferable.

-Solvent water content It is desirable that the water content of these solvents is 1000 ppm or less. Above this water content, it is recognized that the hydrolysis of the raw material phosphorus trichloride is promoted. More preferably, it is 500 ppm or less, and particularly preferably 100 ppm or less.

Catalyst-Catalyst Type A catalyst can be used to efficiently promote the reaction of the phosphorus trichloride of the present invention with pentaerythritol. As such a catalyst, an organic base compound which does not react with a phosphorus atom-chlorine atom bond is preferably used. The organic base compound which does not react with the phosphorus atom-chlorine atom bond is an organic base compound substantially free of a nitrogen atom-hydrogen atom bond and / or an oxygen atom-hydrogen atom bond. Substantially having no such bond means that the amount of nitrogen atom-hydrogen atom bond and oxygen atom-hydrogen atom bond in the organic base compound is 5000 ppm or less, preferably 1000 ppm or less, more preferably 500 ppm or less It is a thing.

  Examples of the organic base compound which does not react with the phosphorus atom-chlorine atom bond include aliphatic or aromatic, non-cyclic or cyclic amines and amides. Examples of these compounds include trimethylamine, triethylamine, tri-n-propylamine, tri-isopropylamine, tri-n-butylamine, triisobutylamine, tri-t-butylamine, trihexylamine, tri-n-octylamine Methyldiethylamine, N, N-dimethylcyclohexylamine, N, N-dimethylbenzylamine, triphenylamine, tribenzylamine, triphenethylamine, N, N-dimethylaniline, N, N-diethylaniline, N, N, N ', N'-tetraethylmethanediamine, N, N, N', N'- tetramethylethylenediamine, N, N, N ', N'- tetramethyl-1, 4-butanediamine, N, N, N', N'-Tetramethyl-1,3-butanediamine, 1-methylpyridine 1-ethylpyrrole, 1-methylpyrrolidine, 1-ethylpyrrolidine, oxazole, thiazole, 1-methylimidazole, 1-ethylimidazole, 1-butylimidazole, 1-methylpyrazole, 1-methylpiperidine, 1-ethyl Piperidine, N, N'-dimethylpiperazine, pyridine, N, N-dimethyl-4-aminopyridine, N, N-diethyl-4-aminopyridine, 2-methoxypyridine, 4-methoxypyridine, 2-methylpyridine, 4 -Methylpyridine, 2,6-dimethylpyridine, 2,4,6-trimethylpyridine, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, quinuclidine, quinazoline, 9-methylcarbazole, acridine, phenanthridine, hexamethylenetetramine, 1 , 8- Azabicyclo [5.4.0] -7-undecene, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,4-diazabicyclo [2.2.2] octane, N, N-dimethylformamide N, N-dimethylacetamide, N, N-diethylacetamide, N, N-diethylpropanamide, N, N-dimethylbenzamide, N-methyl-2-pyrrolidinone, N-methyl-2-pyrrolidone, N-methyl- 2-Piperidone etc. are mentioned.

Among them, triethylamine, triisopropylamine, tri-n-butylamine, N, N, N ', N'-tetramethylethylenediamine, N, N-dimethylaniline, N, N-diethylaniline, pyridine, N, N-dimethyl- Preferred are 4-aminopyridine, 4-methylpyridine, 2,4,6-trimethylpyridine, quinoline, N, N-dimethylformamide, a copolymer of 4-vinylpyridine and styrene, triethylamine, N, N-diethylaniline, Pyridine and N, N-dimethylformamide are more preferable, pyridine and N, N-dimethylformamide are more preferable, and pyridine is particularly preferable.
In addition, the above compounds may be compounds chemically bonded in the polymer. For example, poly (4-vinylpyridine), poly (2-vinylpyridine), a copolymer of 4-vinylpyridine and styrene, and the like can be mentioned.
The organic base compounds can be used not only as a single compound but also in combination of two or more.

-Catalyst amount The existing ratio of the organic base compound catalyst is preferably 0.1 mol% to 100 mol% with respect to 100 mol% of phosphorus trichloride. Moreover, 1 mol%-20 mol% are desirable practically.

Method of mixing phosphorus trichloride and pentaerythritol As a method of mixing phosphorus trichloride and pentaerythritol in the present invention, a method of dropping phosphorus trichloride into a suspension of pentaerythritol is preferable from the viewpoint of working efficiency.

About the dropping rate of phosphorus trichloride The dropping rate of phosphorus trichloride to the pentaerythritol of the present invention (the following formula (i)) is preferably 0.50 to 2.00 (mol / (hr · mol)), Preferably it is 0.55 to 1.50 (mol / (hr · mol)). If the dropping rate of phosphorus trichloride is slower than 0.50 (mol / (hr · mol)), side reactions will proceed and the particle size may be enlarged due to the decrease in purity of pentaerythritol diphosphonate and aggregation via impurities. There is. On the other hand, if the dropping rate of phosphorus trichloride is faster than 2.00 (mol / (hr · mol)), the reaction becomes significantly faster, control may be difficult, and the risk may increase.
(I) Dropping rate of phosphorus trichloride to pentaerythritol (mol / (hr · mol)) = dropping speed of phosphorus trichloride (mol / hr) / amount of pentaerythritol used (mol)

Reaction temperature The reaction temperature in the reaction of phosphorus trichloride with pentaerythritol in the present invention is preferably in the range of -10 ° C to 90 ° C. The temperature is more preferably 0 ° C to 60 ° C, and particularly preferably 5 ° C to 40 ° C. When the reaction temperature is less than -10 ° C, the reaction rate may be significantly reduced, which may lead to a decrease in productivity. On the other hand, if the temperature exceeds 90 ° C., a side reaction may occur, and the recovery amount of the target pentaerythritol diphosphonate may be reduced.

Reaction Time In the present invention, the reaction time for reacting phosphorus trichloride and pentaerythritol is not particularly limited, but it is preferable to react for 1 minute to 500 minutes. More preferably, it is 5 minutes to 300 minutes. If the reaction time is in the above range, the calorific value per unit time and the generation amount of hydrogen chloride gas are small, and it is easy to control the reaction temperature, heat exchangers, coolers, hydrogen chloride gas abatement devices, etc. This is preferable because the equipment load on the The reaction time is preferably in the above range also from the viewpoint of production efficiency.

Regarding the reaction atmosphere It is desirable to always keep the reaction system of phosphorus trichloride and pentaerythritol in the present invention under an inert gas atmosphere. For this purpose, an inert gas such as nitrogen or argon may be introduced into the reaction system. Furthermore, by continuously taking out this gas out of the system, the hydrogen halide gas by-produced is also carried along with this gas and there is an effect that it comes out of the system, and the inert gas is retained in the reaction system. It is preferable to flow in the reaction system rather than letting it flow.

  In the present invention, 3,9-dichloro-2,4,8,10-tetraoxa-3,9-diphosphaspiro [3 by reacting phosphorus trichloride and pentaerythritol in the presence of an inert solvent not involved in the reaction. 5.5] Undecane (hereinafter referred to as "pentaerythritol dichlorophosphite", a compound represented by the above-mentioned formula (1)) is produced, and at the same time, 4 moles of hydrogen chloride is produced per mole of pentaerythritol as a by-product . The pentaerythritol dichlorophosphite compound is an unstable compound.

Removal of Hydrogen Chloride In the present invention, it is preferable to remove hydrogen chloride from the solution or suspension of pentaerythritol dichlorophosphite obtained by the above reaction. As such a method, the following heat treatment or pressure reduction treatment is performed.

-Heat processing Heat processing performs the processing which heats the solution or suspension of pentaerythritol dichloro phosphite to 40-120 ° C. The heat treatment time is preferably in the range of 1 minute to 1 hour, and more preferably in the range of 10 minutes to 30 minutes. Further, the heat treatment is preferably performed in an inert gas atmosphere.

-Reduced pressure treatment In reduced pressure treatment, a solution or suspension of pentaerythritol dichlorophosphite is subjected to treatment for reducing the pressure. The degree of reduced pressure is preferably in the range of 100 to 70,000 Pa, more preferably in the range of 400 to 40,000 Pa, and still more preferably in the range of 800 to 20,000 Pa. In addition, it is preferable that hydrogen chloride be removed but not the reaction solvent or the reaction mixture be removed during the reduced pressure treatment. As a specific method, for example, only hydrogen chloride is treated under reduced pressure at a degree of reduced pressure of about 3,000 Pa through a cooling pipe cooled to 0 ° C. or less while maintaining a solution or suspension of pentaerythritol dichlorophosphite at room temperature. There is a method of removing The time for performing the vacuum treatment varies depending on the amount of solution or suspension of pentaerythritol dichlorophosphite, the degree of vacuum, etc., although it can not be generally said, it may be generally 1 minute to 1 hour, preferably 10 minutes to 30 minutes You should do it.

  The solution or suspension of pentaerythritol dichlorophosphite obtained by the above-mentioned a reaction may isolate and purify pentaerythritol dichlorophosphite from this solution or suspension; It can be used as it is for the reaction of b reaction. By omitting the step of isolating and purifying pentaerythritol dichlorophosphite, it is excellent in terms of workability and production efficiency. In addition, degradation of the inherently unstable pentaerythritol dichlorophosphite compound is minimized, which results in an increase in the recovery rate of pentaerythritol diphosphonate which is the object of the present invention.

(B reaction (second step reaction))
Organic Basic Compound: Kind of Organic Basic Compound In the present invention, it is preferable to allow an organic base compound to coexist when the pentaerythritol dichlorophosphite obtained by the reaction a) is reacted with an aralkyl alcohol. The organic base compound is preferably an organic base compound that does not react with a phosphorus atom-chlorine atom bond. The organic base compound which does not react with the phosphorus atom-chlorine atom bond is an organic base compound substantially free of a nitrogen atom-hydrogen atom bond and / or an oxygen atom-hydrogen atom bond. Substantially having no such bond means that the amount of nitrogen atom-hydrogen atom bond and oxygen atom-hydrogen atom bond in the organic base compound is 5000 ppm or less, preferably 1000 ppm or less, more preferably 500 ppm or less It is a thing.

  Examples of the organic base compound which does not react with the phosphorus atom-chlorine atom bond include aliphatic or aromatic non-cyclic or cyclic amines. Examples of these compounds include trimethylamine, triethylamine, tri-n-propylamine, tri-isopropylamine, tri-n-butylamine, triisobutylamine, tri-t-butylamine, trihexylamine, tri-n-octylamine Methyldiethylamine, N, N-dimethylcyclohexylamine, N, N-dimethylbenzylamine, triphenylamine, tribenzylamine, triphenethylamine, N, N-dimethylaniline, N, N-diethylaniline, N, N, N ', N'-tetraethylmethanediamine, N, N, N', N'- tetramethylethylenediamine, N, N, N ', N'- tetramethyl-1, 4-butanediamine, N, N, N', N'-Tetramethyl-1,3-butanediamine, 1-methylpyridine 1-ethylpyrrole, 1-methylpyrrolidine, 1-ethylpyrrolidine, oxazole, thiazole, 1-methylimidazole, 1-ethylimidazole, 1-butylimidazole, 1-methylpyrazole, 1-methylpiperidine, 1-ethyl Piperidine, N, N'-dimethylpiperazine, pyridine, N, N-dimethyl-4-aminopyridine, N, N-diethyl-4-aminopyridine, 2-methoxypyridine, 4-methoxypyridine, 2-methylpyridine, 4 -Methylpyridine, 2,6-dimethylpyridine, 2,4,6-trimethylpyridine, pyridazine, pyrimidine, pyrazine, quinoline, isoquinoline, quinuclidine, quinazoline, 9-methylcarbazole, acridine, phenanthridine, hexamethylenetetramine, 1 , 8- Azabicyclo [5.4.0] -7-undecene, 1,5-diazabicyclo [4.3.0] -5-nonene, 1,4-diazabicyclo [2.2.2] octane and the like.

Among them, triethylamine, triisopropylamine, tri-n-butylamine, N, N, N ', N'-tetramethylethylenediamine, N, N-dimethylaniline, N, N-diethylaniline, pyridine, N, N-dimethyl- Preferred are 4-aminopyridine, 4-methylpyridine, 2,4,6-trimethylpyridine, quinoline, and a copolymer of 4-vinylpyridine and styrene, and triethylamine, tri-n-butylamine, pyridine, N, N-dimethylaniline N, N-diethylaniline is more preferable, and pyridine, N, N-dimethylaniline and N, N-diethylaniline are particularly preferable.
In addition, the above compounds may be compounds chemically bonded in the polymer. For example, poly (4-vinylpyridine), poly (2-vinylpyridine), a copolymer of 4-vinylpyridine and styrene, and the like can be mentioned.
The organic base compound can be used not only as a single compound but also as a mixture of two or more kinds.

-Usage amount of organic base compound In the present invention, the usage amount of the above organic base compound is preferably 180 mol% to 400 mol% with respect to 100 mol% of pentaerythritol. If the amount is less than 180% by mole, the by-produced hydrogen chloride can not be captured, and the uncaptured hydrogen chloride decomposes the obtained pentaerythritol diphosphite, resulting in that the object of the present invention, penta The recovery of erythritol diphosphonate can be significantly reduced. On the other hand, if the proportion of the organic base compound is more than 400 mol% with respect to pentaerythritol, the load of recovery or disposal of the organic base compound may be large, and the production efficiency may be degraded. More preferably, it is 190 mol% to 250 mol%, still more preferably 195 mol% to 220 mol%.

Water content of the organic base compound The water content of the organic base compound is preferably 2000 ppm or less. When it exceeds 2000 ppm, a by-product derived from water is formed, and the by-product in addition to inhibiting the formation of pentaerythritol diphosphite of the present invention and participating in the decomposition of pentaerythritol diphosphite itself. In addition, as a result, the recovery amount of pentaerythritol diphosphonate which is the object of the present invention may be significantly reduced. More preferably, it is 1000 ppm or less, and particularly preferably 100 ppm or less.

Aralkyl alcohol type of aralkyl alcohol The aralkyl alcohol used in the present invention is a compound represented by the formula (4), and in the formula (4), Ar is a phenyl group, various xylyl groups, various toluyl groups, di- t-butylphenyl group, biphenyl group, naphthyl group etc., R ¹ and R ² are hydrogen atom, methyl group, ethyl group, various propyl groups, various butyl groups, various pentyl groups, propenyl groups, phenyl groups, various toluyl groups Compounds which are a group, various xylyl groups, various cumenyl groups, di-t-butylphenyl groups, biphenyl groups, naphthyl groups and the like are preferable. More preferably, Ar is a phenyl group, R ¹ and R ² are a hydrogen atom, a methyl group and a phenyl group, and particularly preferably Ar is a phenyl group and R ¹ and R ² are a hydrogen atom.

Specifically, benzyl alcohol, (2-methylphenyl) methyl alcohol, (3-methylphenyl) methyl alcohol, (4-methylphenyl) methyl alcohol, (2,4-dimethylphenyl) methyl alcohol, (2, 6 -Dimethylphenyl) methyl alcohol, (3,5-dimethylphenyl) methyl alcohol, (2,4,6-trimethylphenyl) methyl alcohol, (2-sec-butylphenyl) methyl alcohol, (4-sec-butylphenyl) Methyl alcohol, (2,4-di-sec-butylphenyl) methyl alcohol, (2,6-di-sec-butylphenyl) methyl alcohol, (2,4,6-tri-sec-butylphenyl) methyl alcohol, (2-tert-butylphenyl) methyl alcohol, (4 tert-Butylphenyl) methyl alcohol, (2,4-di-tert-butylphenyl) methyl alcohol, (2,6-di-tert-butylphenyl) methyl alcohol, (2,4,6-tri-tert-butyl) Phenyl) methyl alcohol, (4-biphenyl) methyl alcohol, (1-naphthyl) methyl alcohol, (2-naphthyl) methyl alcohol, (1-anthryl) methyl alcohol, (2-anthryl) methyl alcohol, (9-anthryl) Examples include methyl alcohol, 1-phenylethyl alcohol, 1-methyl-1-phenylethyl alcohol, diphenylmethyl alcohol and triphenylmethyl alcohol. Among them, benzyl alcohol, 1-phenylethyl alcohol and diphenylmethyl alcohol are preferable, and benzyl alcohol is particularly preferable.
The aralkyl alcohol can be used not only as a single compound but also as a mixture of two or more.

The amount of the aralkyl alcohol used is preferably 180 mol% to 250 mol% with respect to 100 mol% of pentaerythritol. More preferably, it is 190 mol% to 220 mol%. More preferably, it is 200 mol% to 210 mol%. When the amount of the aralkyl alcohol used is less than 180 mol%, the recovery amount of the pentaerythritol diphosphonate which is the object of the present invention is greatly reduced to the excess of the aralkyl alcohol. When the amount of the aralkyl alcohol used exceeds 250 mol%, the load of the step of recovering the excess aralkyl alcohol and the step of waste treatment may be increased, which may be industrially disadvantageous.

Method for Adding Aralkyl Alcohol The method for reacting pentaerythritol dichlorophosphite and the aralkyl alcohol represented by the above formula (3) in the presence of the organic base compound is not particularly limited. An organic base compound may be added to a solution or suspension of pentaerythritol dichlorophosphite, followed by reaction by adding an aralkyl alcohol, and the aralkyl alcohol may be reacted with a solution or suspension of pentaerythritol dichlorophosphite and organic compounds. A mixture of base compounds may be added, or a solution or suspension of pentaerythritol dichlorophosphite may be added to the mixture of organic base compound and aralkyl alcohol, or a solution or suspension of pentaerythritol dichlorophosphite A mixture of an organic base compound and an aralkyl alcohol may be added to the reaction and reacted.

Reaction Temperature and Pressure In the present invention, the temperature conditions for reacting pentaerythritol dichlorophosphite and an aralkyl alcohol are preferably in the range of -20 ° C to 100 ° C. More preferably, it is -10 ° C to 80 ° C. If it is less than -20 ° C, the reaction rate decreases, leading to a decrease in production efficiency. On the other hand, when the reaction is carried out at a temperature exceeding 100 ° C., the decomposition of pentaerythritol diphosphite results in a reduction in the recovery of pentaerythritol diphosphonate which is the object of the present invention. The reaction is preferably carried out under normal pressure.

Regarding the reaction time In the present invention, the reaction time when reacting pentaerythritol dichlorophosphite and an aralkyl alcohol is not particularly limited, but it is preferable to react over 1 minute to 500 minutes. More preferably, it is 5 minutes to 300 minutes. When the reaction is carried out in less than one minute, the calorific value per unit time is large, which makes it difficult to control the reaction temperature and also increases the load on equipment such as a heat exchanger and a cooler. On the other hand, reaction in time exceeding 500 minutes will reduce production efficiency.

Regarding the Water Content in the Reaction System In the present invention, the water content in the reaction system when reacting pentaerythritol dichlorophosphite and an aralkyl alcohol is preferably 2000 ppm or less. More preferably, it is 1000 ppm or less, still more preferably 500 ppm or less, and particularly preferably 300 ppm or less. When the water content in the reaction system exceeds 2000 ppm, the rate of reduction in recovery rate of the target product becomes greater than the rate at which by-products are produced by the reaction of pentaerythritol dichlorophosphite with water.

About solvent b In the reaction, use an inert solvent not involved in the reaction. When the solution or suspension of pentaerythritol dichlorophosphite obtained by the a reaction is used as it is in the b reaction, it is not necessary to add a new solvent, but may be added. In addition, when pentaerythritol dichlorophosphite is isolated in the a reaction, a solvent is used.
As the solvent, hexane, heptane, octane, decane, dodecane, diethyl ether, dipropyl ether, dipropyl ether, dibutyl ether, tetrahydrofuran, dioxane, methylene chloride, chloroform, carbon tetrachloride, ethyl acetate, benzene, chlorobenzene, ortho-dichlorobenzene, toluene , Xylene, ethylbenzene, propylbenzene, butylbenzene and the like. Preferred are hexane, decane, dodecane, diethyl ether, dibutyl ether, dioxane, chlorobenzene, orthodichlorobenzene, toluene, xylene and ethylbenzene. More preferred are hexane, dodecane, dibutyl ether, chlorobenzene, ortho-dichlorobenzene, toluene, xylene and ethylbenzene. Particularly preferred is xylene.

Reaction Atmosphere When reacting pentaerythritol dichlorophosphite with an aralkyl alcohol, it is desirable to carry out under an inert atmosphere. The inert atmosphere is a state substantially free of oxygen gas, moisture, chlorine gas and the like which can modify the aralkyl alcohol, the organic base compound, the formed pentaerythritol diphosphite and the like used in the present invention.
Specifically, the oxygen concentration in the system is desirably 5% or less, preferably 1% or less, and more preferably 100 ppm or less. A specific example is a method in which the reaction system is replaced with an inert gas such as nitrogen, argon or the like, and then the reaction is carried out under the inert gas flow or in the inert gas atmosphere. The oxygen concentration is measured by a zirconia analysis method or the like specified in JIS B 7983.

Removal of organic base compound component: Removal amount of organic base compound component In the b reaction of the present invention, pentaerythritol diphospha formed when pentaerythritol dichlorophosphite and aralkyl alcohol are reacted in the presence of an organic base compound. It is preferable to remove the organic base compound and the salt of the organic base compound (organic base compound component) out of the reaction system from the reaction mixture containing the phyto.
As a ratio for removing the organic base compound component out of the reaction system, it is desirable to remove 90 mol% or more of the organic base compound component with respect to 100 mol% of the used organic base compound, and 95 mol% or more of the organic base compound component It is further desirable to remove compound components. If the removal rate of the organic base compound is less than 90 mol%, a side reaction may be induced when obtaining pentaerythritol diphosphonate in the following c reaction, and the recovery amount of pentaerythritol diphosphonate may be reduced. The method of removing the organic base compound component depends on various conditions such as the type of the solvent used and the properties of the target substance, but it can not be generically mentioned, but one example is that when xylene is used as the solvent, The base compound forms a hydrogen chloride salt of an organic base compound substantially insoluble in xylene, and thus can be easily removed by an operation such as filtration.

The atmosphere for removing the organic base compound component The operation for removing the organic base compound component out of the reaction system from the generated pentaerythritol diphosphite is preferably performed under an inert atmosphere. The inert atmosphere is a state substantially free of oxygen gas, chlorine gas and the like capable of modifying the pentaerythritol diphosphite of the present invention. Specifically, the oxygen concentration in the system is desirably 5% or less, preferably 1% or less, and more preferably 100 ppm or less. For example, there is a method of performing the cleaning operation or the like under a stream of nitrogen gas, argon gas or the like or under an atmosphere. The oxygen concentration is measured by a zirconia analysis method or the like specified in JIS B 7983.

Treatment after Removal of Organic Base Compound Component A solution or suspension of pentaerythritol diphosphite after removal of the organic base compound component described above isolates pentaerythritol diphosphite from this solution or suspension. Although it is preferable, it is preferable to use this solution or suspension as it is in the next reaction c. By omitting the step of isolating pentaerythritol diphosphite, it is excellent in terms of workability and production efficiency.
In addition, the pentaerythritol diphosphite solution or suspension after removal of the organic base compound component may be used in the following c reaction after being washed with water or an aqueous alkali solution.
Moreover, after removing a part, such as a solvent, from the solution or suspension of pentaerythritol diphosphite after removing the organic base compound component by distillation or the like, it can also be used in the following c reaction.
From the viewpoint of production efficiency, the method of using the pentaerythritol diphosphite solution or suspension after removal of the organic base compound component as it is for the next reaction c, or pentaerythritol diphos after removal of the organic base compound component It is preferable to use the following reaction c after washing the fight solution or suspension with water or an aqueous alkali solution.

(C reaction (3rd step reaction; albuzov reaction))
In the present invention, the pentaerythritol diphosphite obtained in the reaction b is heat-treated in the presence of the halogenated compound represented by the formula (2) under conditions of a temperature of 80 ° C. to 300 ° C. The pentaerythritol diphosphonate shown in 1) is obtained.

Solvent-Type of Solvent In the reaction c of the present invention, a solvent can also be used when heat treating pentaerythritol diphosphite. By using a solvent, pentaerythritol diphosphite can be dissolved or dispersed in the solvent to reduce the load of stirring. Further, there is an advantage that heat can be easily transmitted to the reaction system uniformly in the heat treatment of the present invention.
As the solvent, a solvent consisting of one or more selected from the group consisting of aromatic hydrocarbons, aliphatic hydrocarbons, halogenated hydrocarbons and oxygen-containing atomic hydrocarbons is preferable, and aromatic hydrocarbons and aliphatic carbons are preferable. More preferred are solvents consisting of one or more selected from the group consisting of hydrogen and halogenated hydrocarbons. Moreover, that whose boiling point under a normal pressure is 100 degreeC-300 degreeC is desirable. The solvent is preferably the same solvent type as the inert solvent used in reacting the phosphorus trichloride of the present invention with pentaerythritol in view of the load such as separation and recovery of the solvent.

  As a solvent, specifically, hexane, heptane, octane, decane, dodecane, diethyl ether, dipropyl ether, dipropyl ether, dibutyl ether, tetrahydrofuran, dioxane, methylene chloride, chloroform, carbon tetrachloride, benzene, chlorobenzene, chlorobenzene, ortho-dichlorobenzene, toluene, Xylene, ethylbenzene, propylbenzene, butylbenzene and the like can be mentioned. Those having a boiling point of 100 ° C. to 300 ° C. under normal pressure are suitably used, and such substances include decane, dodecane, dibutyl ether, dioxane, chlorobenzene, orthodichlorobenzene, toluene, xylene, ethylbenzene and the like. Particularly preferred is xylene.

-Amount of solvent The amount of solvent used is preferably 0.1 to 5 mol / L, more preferably 0.3 to 3 mol / L, as represented by the molar concentration of pentaerythritol used in the present invention. If it is less than 0.1 mol / L, the production rate of pentaerythritol diphosphonate may extremely decrease, which may lead to a decrease in production efficiency.

About heating temperature In reaction c of the present invention, pentaerythritol diphosphonate can be obtained by heat treatment of pentaerythritol diphosphite in the coexistence of a halogenated compound. At that time, the temperature of the heat treatment is preferably 80 ° C. to 300 ° C., and the temperature of the heat treatment is more preferably 100 ° C. to 250 ° C. If the temperature of the heat treatment is less than 80 ° C., the reaction rate may be significantly reduced and the production efficiency may be degraded. When the temperature of the heat treatment exceeds 300 ° C., side reactions may be promoted to cause a reduction in recovery of pentaerythritol diphosphonate.

The reaction time of the heat treatment in the reaction c of the present invention is preferably 1 minute to 1200 minutes, and more preferably 10 minutes to 1000 minutes. Less than one minute may leave unreacted products, which may cause a reduction in the recovery of the target pentaerythritol diphosphonate. On the other hand, if it exceeds 1200 minutes, the production efficiency may be deteriorated.

Regarding Halogenated Compound-Type of Halogenated Compound In the reaction c of the present invention, a halogenated compound represented by the above formula (2) is used as a catalyst.
In the halogenated compound represented by the formula (2), Ar ³ is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, preferably a substituted or unsubstituted aryl group having 6 to 10 carbon atoms. R ⁷ and R ^{8, which} may be the same or different, are a hydrogen atom or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms, preferably a hydrogen atom or 1 to 8 carbon atoms It is a saturated or unsaturated linear or branched alkyl group, more preferably a hydrogen atom or a C1-C4 saturated or unsaturated linear or branched alkyl group, particularly preferably a hydrogen atom. X is a Br group.
Specific examples of the halogenated compound include benzyl bromide, (1-bromoethyl) benzene, (2-bromoethyl) benzene, diphenylmethyl bromide and the like, and among them benzyl bromide, (1-bromoethyl) benzene, (2- Bromoethyl) benzene is preferred, in particular benzyl bromide.
By using the halogenated compound represented by the above formula (2), in comparison with other halogenated compounds (for example, sodium iodide, tetrabutylammonium bromide, n-butyliodide) which are usually used as a catalyst, A high yield of pentaerythritol diphosphonate can be obtained in high yield.

The amount of the halogenated compound used The amount of the halogenated compound represented by the formula (2) used in the present invention is not particularly limited, but it is 1 mole to 10 moles with respect to 1 mole of pentaerythritol used in the present invention Is preferred, and 1.5 to 3 moles are particularly preferred.

About the Albuzoff reaction system Water content Although the water content in the reaction system in the reaction c of the present invention is not particularly specified, 2000 ppm or less is desirable. More preferably, it is 1000 ppm or less. When the water content is more than 2000 ppm, the reason is unknown, but the recovery rate of the target product is reduced more than the proportion of by-products thought to be derived from the reaction between pentaerythritol diphosphite used in the present invention and water. The proportion will increase.

Alcohol Amount The amount of alcohol in the reaction system in the reaction c of the present invention is preferably 30,000 ppm or less. More preferably, it is 10000 ppm or less. The alcohol may be mixed in the process of producing pentaerythritol diphosphite, and the recovery rate of the desired pentaerythritol diphosphonate decreases significantly when using pentaerythritol diphosphite containing a large amount of the alcohol. .

Reaction atmosphere The heat treatment in the reaction c of the present invention is preferably performed under an inert atmosphere. The inert atmosphere is a state in which there is substantially no oxygen gas, moisture and the like that can modify pentaerythritol diphosphite and the like used in the present invention. Specifically, the oxygen concentration in the system is desirably 5% or less, preferably 1% or less, and more preferably 100 ppm or less. A specific example is a method in which the inside of the reaction system is replaced with an inert gas such as nitrogen, argon or the like, and then heat treatment is performed in the inert gas flow or in the inert gas atmosphere. The oxygen concentration is measured by a zirconia analysis method or the like specified in JIS B 7983.

(Washing process)
In the present invention, the pentaerythritol diphosphonate obtained in the c reaction is preferably purified by the following washing method.

About washing solvent and washing temperature Such purification means a compound represented by the general formula R ⁹ -OH or R ¹⁰ -C (O) -R ¹¹ (R ⁹ is a hydrogen atom or a linear chain having 1 to 6 carbon atoms and saturated Or a branched alkyl group, R ¹⁰ and R ¹¹ may be the same or different, and is a saturated linear or branched alkyl group having 1 to 6 carbon atoms.) To obtain a target pentaerythritol diphosphonate To wash the The washing temperature at that time is preferably 35 ° C. to 120 ° C. or less. Within this washing temperature range, the formed pentaerythritol diphosphonate is less likely to be decomposed, and the washing effect is high, in order to obtain the pentaerythritol diphosphonate having a reduced content of residual volatiles, There is no need to repeat the process, which is preferable in terms of production efficiency. By adopting the above-mentioned washing method, the powdery pentaerythritol diphosphonate obtained by the reaction c becomes scaly crystals and has excellent drying properties.
Examples of the compound represented by the above general formula R ⁹ -OH include water, methanol, ethanol, propanol, isopropyl alcohol, butanol and the like, and a compound represented by the above general formula R ¹⁰ -C (O) -R ¹¹ Examples thereof include acetone, methyl ethyl ketone, methyl isobutyl ketone and the like, and among them, methanol is preferable from the viewpoint of economy and operability.

About the solubility of pentaerythritol diphosphonate in the washing solvent under the washing time and the temperature condition when washing, in the washing step of the present invention, it is preferable to carry out the repulp washing under the condition satisfying the following formula (I), It is more preferable to carry out the repulp washing under the conditions satisfying the condition II), and it is further preferable to carry out the repulping wash under the conditions satisfying the following formula (III).
(I) 8 ≦ X × Y ² ≦ 45
(II) 10 ≦ X × Y ² ≦ 40
(III) 15 ≦ X × Y ² ≦ 35
(Wherein, X is the washing time (h) and Y is the solubility (g / 100 g-solvent) of pentaerythritol diphosphonate in the washing solvent under the temperature conditions for washing.)
When X × Y ² is less than 8, the cleaning effect is insufficient, and there is a possibility that the particle size may be increased due to the decrease in purity or the aggregation through the impurities. Moreover, since content of the halogenated compound shown by Formula (2) contained in pentaerythritol diphosphonate also increases and an irritant smell remains, it is unpreferable from a practical viewpoint. On the other hand, when X × Y ² exceeds 45, crystal growth of pentaerythritol diphosphonate due to Ostwald growth may be remarkable, and the particle size may be enlarged.

Regarding the amount of washing solvent The amount of the washing solvent used is preferably 0.1 to 5 mol / L, more preferably 0.3 to 3 mol / L, as represented by the molar concentration of pentaerythritol used in the present invention. If the amount is 0.1 mol / L or more, the amount of solvent used for washing is small, which is preferable from the economical point of view. Further, in the case of 5 mol / L or less, since the slurry concentration is low and the viscosity is also appropriate, the load on the stirrer becomes small, which is preferable. In addition, since the slurry concentration is low, the washing efficiency is high, and there is no need to repeat the washing many times in order to obtain the pentaerythritol diphosphonate of high purity, which is preferable in terms of production efficiency.
When the above purification method is applied, highly pure pentaerythritol diphosphonate having a reduced content of the halogenated compound represented by formula (2) is obtained. Furthermore, the above purification method can provide pentaerythritol diphosphonate having particle properties suitable for use as a flameproofing agent for fibers.

(Drying process)
In the present invention, the pentaerythritol diphosphonate obtained by the c reaction is preferably dried by either vacuum drying or hot air drying.
The drying temperature for vacuum drying is preferably 30 to 180 ° C., more preferably 40 to 160 ° C., still more preferably 50 to 140 ° C., and the vacuum degree for vacuum drying is preferably 0 to 70 Torr. The drying time is preferably 10 to 90 hours, more preferably 15 to 80 hours, and still more preferably 20 to 70 hours. By drying under reduced pressure in the above range, high quality pentaerythritol diphosphonate with less residual solvent can be obtained.

The drying temperature at the time of hot air drying is preferably 80 to 200 ° C., more preferably 90 to 180 ° C., still more preferably 100 to 160 ° C., and the drying time is preferably 10 to 90 hr, more preferably 15 to 50 hr. It is preferably 80 hr, more preferably 20 to 70 hr. By performing hot air drying in the above range, it is possible to obtain high quality pentaerythritol diphosphonate with less residual solvent.
As a heating device used for the drying step, a rotary heating device such as a continuous heating / drying device, a tumble dryer, a conical dryer, a rotary dryer or the like, and a rotary drum heating device and a Nauta mixer Although a conical heating device can be suitably used, it is possible to use known methods and devices without being limited thereto.

(Processing agent)
The pentaerythritol diphosphonate produced by the method of the present invention is suitably used as a flameproofing agent for fibers. The flameproofing agent for fibers can be obtained by mixing 1 to 300 parts by weight of pentaerythritol diphosphonate represented by the above formula (1) in 100 parts by weight of a dispersant.
As the dispersant, water, an organic solvent or a resin (including a solution, an emulsion and a latex) is preferably used.

As a method of preparing the flameproofing agent, a method of mixing and dispersing the pentaerythritol diphosphonate represented by the above formula (1) in water, an organic solvent or resin solution, a resin emulsion and a latex is preferable. Moreover, the surfactant, the stabilizer, the other flameproofing agent etc. which were mentioned above can be used as needed.
At this time, the mixing ratio of pentaerythritol diphosphonate represented by the above formula (1) is preferably 5 to 200 parts by weight, more preferably 10 to 100 parts by weight, particularly preferably 20 to 50 parts by weight with respect to 100 parts by weight of the dispersant. It is a department. When the amount of pentaerythritol diphosphonate represented by the above formula (1) is less than 1 part by weight, the flameproof effect may not be sufficient, and when it is more than 300 parts by weight, the film formation of the resin tends to deteriorate. The quality of textile products may be reduced.

  Then, the obtained flameproofing agent for fiber is adhered to the fiber product in a solid content of 3 to 150% by weight to produce a flameproof fiber product. The solids content is preferably 7 to 100% by weight, particularly preferably 15 to 70% by weight. If the solid content is less than 3% by weight, the flameproofing effect is insufficient, and if it is more than 150% by weight, the quality of the fiber product is degraded. The processing method is not particularly limited, and the conventional immersion method, processing by spraying (spray etc.), coating method such as brush coating, exhaustion method (dye same bath method), thermosol method It is generally used.

  Moreover, although it does not specifically limit regarding textiles, A curtain, a carpet, a carpet, an artificial turf, wall coverings, a chair covering, curtains (A banner etc.), a car seat, a car mat, a nonwoven fabric filter as a representative example , Artificial leather, electromagnetic shielding materials, etc. The type of fiber material is also not particularly limited, but representative examples include synthetic fibers such as polyester, nylon, acrylonitrile and polypropylene, cellulose fibers such as rayon, cotton and hemp, or animal properties such as wool, silk and feather A fiber etc. are mentioned and you may use individually or in a composite state.

The pentaerythritol diphosphonate produced by the method of the present invention is also suitably used as a flame retardant processing agent for synthetic leather. The method for producing the flame-retardant synthetic leather is not particularly limited, and may be produced by any of a wet method and a dry method.
The wet method as used herein refers to coating a resin for the skin, which is dissolved in a solvent at a predetermined concentration, on a fiber substrate, solidifying it in a coagulation bath containing a poor solvent, and forming a large amount of sponge in the resin layer. This method is to produce fine through holes, and then water washing and drying steps to make a product.

  In the dry method, a surface coating resin dissolved in a solvent at a predetermined concentration is coated on a fiber base material by a known coating method, and the solvent is evaporated by a dryer to solidify the resin, or a release paper is used The surface resin is applied and dried by the same known coating method to form a surface resin layer. As the release paper mentioned here, there are silicone type, polypropylene type and the like, and the surface treatment shape is also flat type, enamel type, mat type, embossed type and the like, but it is not limited. Then, a polyurethane resin adhesive is applied onto the surface resin layer by a known coating method, and the laminate is laminated with a fiber base by thermocompression bonding and dried to obtain a product.

Specifically, it can be manufactured by the following method.
A composition containing a skin resin (for example, a polyurethane resin) is applied on a release paper, and if necessary, heat treatment and aging treatment is performed to form a skin resin layer. Next, a composition containing an adhesive (for example, hot melt polyurethane) in a heat-melted state is applied to the surface of the outer surface resin layer, and the prepolymer composition is bonded to a fiber substrate in a viscous state. Cool to room temperature and age to form an adhesive layer. Finally, release the release paper.

As the epidermal resin composition, the pentaerythritol diphosphonate represented by the above formula (1) is added to the resin emulsion for epidermis or the resin solution for the epidermis, and after addition of a crosslinking agent, a pigment, etc. as necessary, uniform It is preferable to use a working fluid prepared by dispersing.
As a method of apply | coating a surface resin composition (processing liquid) on release paper, the conventionally well-known various methods can be employ | adopted and it does not specifically limit. For example, the method using apparatuses, such as a reverse roll coater, a spray coater, a roll coater, a gravure coater, a kiss roll coater, a knife coater, a comma coater, and a T-die coater, can be mentioned. Above all, coating with a knife coater or comma coater is preferred in that uniform thin film layer formation is possible.

  In addition, as a composition containing an adhesive, the pentaerythritol diphosphonate represented by the above formula (1) is added to the resin emulsion for adhesive layer or the resin solution for adhesive layer, and, if necessary, a crosslinking agent etc. It is preferable to use a processing fluid prepared by uniformly dispersing after being added. As a method of apply | coating the composition (process liquid) containing an adhesive agent to a skin resin layer, the conventionally well-known various methods which were mentioned above are employable.

  The pentaerythritol diphosphonate produced by the method of the present invention is generally used in high-speed rotary impact mills, roll mills, media mills, air-flow mills, shear and grinding mills, etc. A grinding mill can be used to additionally grind and use it as a flameproofing agent for textiles or a flameproofing agent for synthetic leather.

  The pentaerythritol diphosphonate produced by the method of the present invention is also suitably used as a flame retardant such as styrene resin (impact polystyrene, polystyrene, ABS resin, etc.), polyester resin, polyamide resin, etc. Such a flame retardant resin composition has extremely high flame retardancy and is useful as a material for molding various molded articles such as home appliance parts, electric / electronic parts, automobile parts, machinery / mechanism parts, cosmetic containers and the like. It is. Specifically, breaker parts, switch parts, motor parts, ignition coil cases, power plugs, power outlets, coil bobbins, connectors, relay cases, fuse cases, fly back transformer parts, focus block parts, distributor caps, harness connectors, etc. Can be suitably used. In addition, housings, casings or chassis which are becoming thinner, for example, housings for electronic and electronic products (for example, home appliances such as telephones, personal computers, printers, fax machines, copy machines, VCRs, audio equipment, OA equipment or parts thereof) Useful for casings or chassis. It is also useful as a printer housing that requires particularly excellent heat resistance and flame resistance, as a fixing unit part, and as a machine / mechanism part for home appliances such as fax machines and OA products.

  EXAMPLES The present invention will be described by way of examples below, but the present invention is not limited to these examples. In addition, evaluation was performed by the following method.

(1) Moisture content of raw material It measured by the Karl-Fisher method using Mitsubishi Chemical Co., Ltd. coulometric-titration-type moisture measuring device CA-06 type | mold.

(2) Measurement of purity of pentaerythritol diphosphonate Separations Module 2690 manufactured by Waters as an HPLC apparatus, Dual λ Absorbance Detector 2487 (UV-264 nm) manufactured by Waters as a detector, TSKgel ODS-120T manufactured by Tosoh Corp. as a column. Using a mixture of distilled water and acetonitrile as eluent using 0 mm × 150 mm (5 μm), column temperature 40 ° C. 0 → 12 min: acetonitrile 50%, 12 → 17 min: acetonitrile 50 → 80%, 17 → 27 min HPLC analysis was performed with a gradient program of 80% acetonitrile, 27 → 34 min: 80% acetonitrile to 100%, and 34 → 60 min: 100%. The measurement was made by dissolving 50 ± 0.5 mg of pentaerythritol diphosphonate in 25 ml of acetonitrile, and then filtering and measuring it with a PTFE filter with a pore size of 0.2 μm. Purity was calculated as area%.

(3) Residual amount of the halogenated compound represented by Formula (2) contained in pentaerythritol diphosphonate Separations Module 2690 manufactured by Waters as an HPLC apparatus, Dual λ Absorbance Detector 2487 (UV-264 nm) manufactured by Waters as a detector As a column, TSKgel ODS-120T 2.0 mm × 150 mm (5 μm) manufactured by Tosoh Corp., using a mixed solution of distilled water and acetonitrile as an eluent, column temperature 40 ° C. 0 → 12 min: acetonitrile 50% , 12 → 17 min: acetonitrile 50 → 80%, 17 → 27 min: acetonitrile 80%, 27 → 34 min: acetonitrile 80 → 100%, 34 → 60 min: 100% gradient program HPLC analysis was performed. The measurement was made by dissolving 50 ± 0.5 mg of pentaerythritol diphosphonate in 25 ml of acetonitrile, and then filtering and measuring it with a PTFE filter with a pore size of 0.2 μm. The remaining amount of the halogenated compound represented by the formula (2) in pentaerythritol diphosphonate was determined using a calibration curve prepared in advance.

(4) Measurement Method of Median Diameter The median diameter was measured using Microtrac HRA manufactured by Nikkiso Co., Ltd. Measurement conditions were particle permeability: transmission, particle shape: non-spherical, particle refractive index: 1.60, solvent refractive index: 1.33.

(5) Flameproofness According to FMVSS-302, the flameproofness was evaluated. In the evaluation, the burning distance from the marked line, the burning time from the marked line, and the burning rate from the marked line were measured three times as defined in FMVSS-302. Incombustible indicates self-extinguishing below the marked line, and late burning indicates self-extinguishing within 60 seconds and 5 cm or less of the marked line. The combustion speed is 1
Those exceeding 0 cm / min are disqualified.

(6) Light resistance The light resistance was determined by using a fade meter to determine the degree of color change after irradiation at 83 ° C. for 200 hours. (JIS-L 0842, carbon arc method; grade determined the degree of change color according to the blue scale for JIS change color)

(7) Heat resistance The heat resistance was evaluated by examining the degree of discoloration after treatment at 150 ° C. for 60 minutes in a gear oven dryer according to the following criteria.
○: no color change Δ: color change

(8) Texture The texture was judged by the touch with the hand.

(9) Choking Test A test piece of appropriate size was cut out from the sheet cloth produced in the example and the comparative example, and the resin-processed surface was scratched with a nail to observe the degree of whitening. Evaluation criteria are as follows.
○: almost no whitening :: whitening but little powder dropping ×: whitening, powder dropping

(10) Color Eyes The color eyes of the resin-processed surface of the sheet cloth produced in Examples and Comparative Examples were visually observed. Evaluation criteria are as follows.
:: aggregate is present and totally whiteish Δ: aggregate is not observed but overall whitened ×: almost neither aggregate nor whiteness is observed

Each reagent used in the examples is as shown below.
(1) Pentaerythritol Pentaerythritol (99.4% purity) manufactured by Koei Perstorp Co., Ltd. was used. The water content was 34 ppm.
(2) Phosphorus trichloride Phosphorus trichloride having a purity of 99% or more manufactured by Mikuni Pharmaceutical Co., Ltd. was used.
(3) N, N-diethylaniline N, N-diethylaniline manufactured by Samsung Chemical Laboratory Co., Ltd. was used. The water content was 65 ppm.
(4) Pyridine Pyridine manufactured by Hiroei Chemical Industry Co., Ltd. was used.
(5) Xylene Xylene purchased from Sojitz Corporation was used. The water content was 54 ppm.
(6) Benzyl alcohol Benzyl alcohol manufactured by Tokyo Ohka Kogyo Co., Ltd. was used. The water content was 30 ppm.
(7) Benzyl bromide Benzyl bromide manufactured by Bohai Kagaku Co., Ltd. was used. The water content was 25 ppm.
(8) Methanol Methanol manufactured by Mitsubishi Gas Chemical Company, Inc. was used.

Example 1
(A) a Reaction A reaction vessel and a stirring blade are used as main devices, and a heat exchange device, a cooling device, a heating device, a rectification column, a dropping device, a vacuum pump etc. are provided as incidental equipment to prevent corrosion. After the lined reactor was thoroughly dried by nitrogen bubbling, 896.1 kg (1042 L) of xylene, 269.5 kg (1979 mol) of pentaerythritol and 6.36 kg (80 mol) of pyridine were added to the reactor.
560.8 kg (4084 mol) of phosphorus trichloride was added to the dropping apparatus. The refrigerant at −20 ° C. was passed through the rectification column, and stirring was started. The internal temperature was adjusted to about 20 ° C., and the phosphorus trichloride was dropped over 3.4 hours. The temperature in the system increased by about 2 ° C. immediately after the start of dropwise addition, and thereafter was almost constant around 20 ° C. After completion of the dropwise addition, stirring is continued as it is under the temperature condition of 20 ° C. for 1 hour to allow 3,9-dichloro-2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane (hereinafter referred to as pentacene). A white suspension of erythritol (referred to as erythritol dichlorophosphite) was obtained. Hydrogen chloride generated during the reaction was absorbed to the aqueous sodium hydroxide solution outside the reaction system through the rectification column. Thereafter, the internal temperature was adjusted to 60 ° C., and the reaction was completed by continuing stirring for 1 hour.
After cooling down to an internal temperature of 50 ° C. or less, the internal temperature was adjusted to about 50 ° C. by reducing the pressure to 25 Torr by a vacuum pump, and the white suspension was stirred for 1 hour to remove hydrogen chloride remaining in the system . The gas discharged from the vacuum pump was blown into the aqueous sodium hydroxide solution. After depressurizing treatment, the vacuum pump was stopped, and after cooling to 40 ° C. or less, the reactor was flushed with nitrogen and returned to normal pressure.

(B) b Reaction Next, 432.3 kg (3998 mol) of benzyl alcohol and 367.3 kg (327 L) of xylene were added to the dropping apparatus. The reactor was charged with 596.7 kg (3998 moles) of N, N-diethylaniline and 491.9 kg (572 liters) of xylene. The refrigerant was stirred while flowing while flowing through the rectification column. After the jacket was flushed with brine and the internal temperature was cooled to 5 ° C., a xylene solution of benzyl alcohol was added dropwise over 6 hours. The reaction system became a white slurry as the dropping progressed. The temperature inside the system during dropping was adjusted to be about 10 ° C. After completion of the dropwise addition, the internal temperature is raised to 20 ° C. over 30 minutes and maintained for 1 hour as it is, 3,9-bis ((phenylmethyl) oxy) -2,4,8,10-tetraoxa-3,9-diphosphaspiro [5.5] A reaction mixture containing undecane (hereinafter referred to as pentaerythritol dibenzyl phosphite) was obtained.
The resulting reaction mixture was filtered under a nitrogen atmosphere using a centrifugal filter to obtain a solution of pentaerythritol dibenzyl phosphite. 1167 kg (1358 L) of dry xylene was used to wash the white solid on the filter cloth of the centrifugal filter. When the white solid on the filter cloth was added to an aqueous solution of sodium hydroxide, it separated into two layers, and the upper layer was N, N-diethylaniline. The weight of the upper layer and 1 H NMR purity indicated that 95% of the N, N-diethylaniline used was recovered.

(C) c reaction The pentaerythritol dibenzyl phosphite solution obtained in the above (B) is mainly used as a reaction vessel and a stirring blade, and a heat exchange device, a cooling device, a heating device, a rectification column, and a dropping device as incidental equipment. , A vacuum pump etc., and the inside was glass-lined in order to avoid corrosion, and it transferred to the reactor fully dried by nitrogen ventilation. Cool the refrigerant into a rectification column, start cooling, start stirring, adjust the internal temperature to 45 ° C, reduce the pressure inside the system to 10 Torr by a vacuum pump and distill off 1109 kg (1290 L) of xylene, pentaerythritol dibenzyl The phosphite solution was concentrated. After depressurizing treatment, the vacuum pump was stopped, and after cooling to 20 ° C. or less, the reactor was flushed with nitrogen and returned to normal pressure.
Next, 674.2 kg (3942 mol) of benzyl bromide was added, and heating was started under a nitrogen atmosphere. After reaching an internal temperature of 130 ° C., the reaction was carried out for 16 hours. Meanwhile, the internal temperature was controlled to 135 to 145 ° C. The inside of the reactor was refluxed at 135 ° C., and a white precipitate gradually precipitated from the homogeneous solution to form a white slurry. After the reaction was completed, it was cooled to room temperature, and 700 kg (814 L) of xylene was added to the white slurry. After stirring until uniform, the resulting reaction mixture is filtered off under a nitrogen atmosphere using a centrifugal filter, and 3,9-bis (phenylmethyl) -2,4 on the filter cloth of the centrifugal filter. There were obtained crude crystals of 8,10-tetraoxa-3,9-diphosphaspiro [5.5] undecane (hereinafter, pentaerythritol dibenzyl phosphonate). After centrifugal filtration, pentaerythritol dibenzyl phosphonate on the filter cloth was simply washed (cross-washed) using 1194 kg (1389 L) of xylene.

(D) Cleaning process The reaction vessel and the stirring blade are used as main equipment, and a heat exchange device, a cooling device, a heating device, a rectification column, etc. are provided as incidental equipment, in order to avoid corrosion Then, 1392 kg (1760 L) of methanol was added as a washing solvent. Subsequently, the crude pentaerythritol dibenzyl phosphonate obtained in (C) above was charged, and stirring was started. The internal temperature was adjusted to 65 ° C. and washing was performed for 4 hours. Methanol was refluxing at 65 ° C. inside the reactor. After washing, the solution was cooled to room temperature and filtered under a nitrogen atmosphere using a centrifugal filter to obtain crystals of pentaerythritol dibenzyl phosphonate on the filter cloth of the centrifugal filter. After centrifugal filtration, 571 kg (721 L) of methanol was used to simply wash (spout) pentaerythritol dibenzyl phosphonate on the filter cloth.

(E) Drying Step The pentaerythritol dibenzyl phosphonate obtained in the above (D) is transferred to a conical dryer, the internal temperature is adjusted to 60-80 ° C., the pressure is reduced to 10 Torr or less, and drying is performed for 40 hours under reduced pressure. I got 662 kg.
It was found that a pentaerythritol dibenzyl phosphonate having a purity of 99.8%, a residual amount of the halogenated compound of 32 ppm, and a median diameter of 13 μm was obtained in a yield of 81.9%. The production conditions and the analysis results are shown in Tables 1 to 3.

(Preparation of flameproofing agent for textiles)
The car seat cloth for automobile interior was coated with the following working fluid and then tested for flame resistance and physical properties.
(Test cloth): 100% polyester fabric car seat cloth (Attachment 300 g / m ² )
(Processing agent): 1.5 parts of a nonionic surfactant, 1 part of a polyacrylic acid-based thickener and 0.5 parts of 25% ammonia water are added to 100 parts of a polyacrylic acid ester emulsion having a solid content of 45%, and the mixture is stirred While adding 30 parts of pentaerythritol dibenzyl phosphonate obtained in (E) above.
(Processing method): Coating was performed by a doctor knife method. The solid content adhesion amount of the processing agent (processing liquid) was 100 g / m ² . Drying was carried out at 80 ° C. for 5 minutes for pre-drying and 1 minute at 150 ° C. for curing.
(Test results): Table 4 shows the evaluation results of flame resistance, weather resistance, heat resistance, texture, chalking resistance, and color.

[ Examples 2-3, 5-7, Reference Example 4, Comparative Examples 1-3]
The same operation as in Example 1 was carried out except for the conditions shown in Tables 1 to 3 to obtain pentaerythritol dibenzyl phosphonate, and a flameproofing agent for fibers was produced. The evaluation results are shown in Table 4.

Comparative Example 4
In Example 1 (A), the amounts of pentaerythritol, phosphorus trichloride, solvent and catalyst used are changed as shown in Table 1, and the dropping rate of phosphorus trichloride is 0.28 (mol / (hr · mol)). The same operation as in Example 1 was performed except that the procedure of Example 1 was repeated. During the addition of phosphorus trichloride, stirring was not possible, and the final product pentaerythritol dibenzyl phosphonate was not obtained.

Comparative Example 5
The same operation as in Example 1 was performed except that N, N-diethylaniline was not used in (B) of Example 1. The final product pentaerythritol dibenzyl phosphonate was not obtained.

Comparative Example 6
The same operation as in Example 1 was carried out except that in (B) of Example 1, the reaction mixture containing pentaerythritol dibenzyl phosphite was used in the reaction of (C) without filtering. The final product pentaerythritol dibenzyl phosphonate was not obtained.

Comparative Example 7
The procedure of Example 1 was repeated except that 30 parts of trisdichloropropyl phosphate was added instead of pentaerythritol dibenzyl phosphonate in Example 1 to prepare a flameproofing agent for fibers, and a test was conducted. The evaluation results are shown in Table 4.

Comparative Example 8
Example 1 was repeated except that 30 parts of a mixture of 75% of decabromodiphenyl ether and 25% of antimony trioxide was added instead of pentaerythritol dibenzyl phosphonate to prepare a flameproofing agent for fibers. The operation was performed and the test was performed. The evaluation results are shown in Table 4.

Comparative Example 9
A test was conducted in the same manner as in Example 1 except that in Example 1, a 100% polyester woven car sheet cloth was used as it was without coating with a processing agent. The evaluation results are shown in Table 4.

  The pentaerythritol diphosphonate compound having the specific structure of the present invention exhibits an excellent effect as an additive such as a flame retardant, a crystal nucleating agent, a plasticizer and the like, and in particular, a high flame resistance as a flameproofing agent for fibers And since it can impart good physical properties, it is widely useful for applications such as flameproof fiber products, and its industrial effects are outstanding.

Claims (20)

Pentaerythritol diphosphonate represented by the following formula (1), wherein (i) the volume standard median diameter is 22 μm or less, (ii) the purity is 98% or more, and (iii) to the following formula (2) Pentaerythritol diphosphonate characterized in that the content of the halogenated compound shown is 200 ppm or less.

(Wherein, Ar ¹ and Ar ² may be the same or different and each is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ³ , R ⁴ , R ⁵ and R ⁶ are And each may be the same or different, and is a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms.)

(Wherein, Ar ³ is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ⁷ and R ⁸ may be the same or different, and are hydrogen atoms or 1 to 20 carbon atoms. A saturated or unsaturated linear or branched alkyl group, and X is a Br group.) The (i) volume-based median diameter of the pentaerythritol diphosphonate represented by the formula (1) is 20 μm or less, (ii) the purity is 99% or more, and (iii) the halogen represented by the formula (2) The pentaerythritol diphosphonate according to claim 1, wherein the content of the at least one compound is 150 ppm or less. The pentaerythritol diphosphonate according to claim 1, wherein the pentaerythritol diphosphonate represented by the formula (1) is a dibenzylpentaerythritol diphosphonate represented by the following formula (1-a).

(A) Phosphorous trichloride is added dropwise to the pentaerythritol at a dropping rate of 0.50 to 2.00 (mol / (hr · mol)) while phosphorus trichloride and pentaerythritol are in the presence of an inert solvent To give pentaerythritol dichloro phosphite represented by the formula (3) (a reaction), (B) the pentaerythritol dichloro phosphite is reacted with the aralkyl alcohol represented by the formula (4) to obtain a formula 5) to obtain pentaerythritol diphosphite (reaction b), (C) the pentaerythritol diphosphite in the presence of the halogenated compound represented by the formula (2), at a temperature of 80 ° C. to 300 ° C. Heat treatment under conditions to obtain crude crystals of pentaerythritol diphosphonate (reaction c), (D) washing temperature 3 under conditions satisfying the following formula (I) Perform repulping washing at to 65 ° C. (washing step), (E) drying under reduced pressure or performing hot air drying (drying step) The method of producing pentaerythritol diphosphonate of formula (1), characterized in that.
(I) 10 ≦ X × Y ² ≦ 40
(Wherein, X is the washing time (h) and Y is the solubility (g / 100 g-solvent) of pentaerythritol diphosphonate in the washing solvent under the temperature conditions for washing.)

Wherein Ar is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, and R ¹ and R ² may be the same or different, and a hydrogen atom or a substitution of 6 to 20 carbon atoms Or an unsubstituted aryl group, or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms.)

(Wherein, Ar ¹ and Ar ² may be the same or different and each is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ³ , R ⁴ , R ⁵ and R ⁶ are And each may be the same or different, and is a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms.)

(Wherein, Ar ³ is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ⁷ and R ⁸ may be the same or different, and are hydrogen atoms or 1 to 20 carbon atoms. A saturated or unsaturated linear or branched alkyl group, and X is a Br group.)

(Wherein, Ar ¹ and Ar ² may be the same or different and each is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ³ , R ⁴ , R ⁵ and R ⁶ are And each may be the same or different, and is a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms.)   The method for producing pentaerythritol diphosphonate according to claim 4, wherein the solution or suspension of pentaerythritol dichlorophosphite obtained in the reaction a) is subjected to heat treatment and / or reduced pressure treatment.   The method for producing pentaerythritol diphosphonate according to claim 4, wherein pentaerythritol dichlorophosphite is not isolated from the solution or suspension of pentaerythritol dichlorophosphite obtained in the a reaction, but is used for the next b reaction. .   In the a reaction, the inert solvent to be used is a solvent comprising one or more selected from the group consisting of aromatic hydrocarbon, aliphatic hydrocarbon, halogenated hydrocarbon and oxygen atom containing hydrocarbon. The manufacturing method of the pentaerythritol diphosphonate of Claim 4.   The method for producing pentaerythritol diphosphonate according to claim 4, wherein the phosphorus trichloride is used in an amount of 195 mol% to 240 mol% with respect to pentaerythritol in the reaction a.   The method for producing pentaerythritol diphosphonate according to claim 4, wherein the a reaction is carried out in the presence of an organic base compound.   The method for producing pentaerythritol diphosphonate according to claim 4, wherein the reaction b is carried out in the presence of an organic base compound.   The method for producing pentaerythritol diphosphonate according to claim 10, wherein the organic base compound is used at 180 mol% to 400 mol% with respect to pentaerythritol in the reaction b.   The organic base compound and a salt of the organic base compound (hereinafter, referred to as an organic base compound component) are separated and removed from the reaction system from the reaction mixture containing pentaerythritol diphosphite obtained in the above b reaction, and the organic base compound 11. The method for producing pentaerythritol diphosphonate according to claim 10, wherein pentaerythritol diphosphite from which components have been removed is used in the reaction c.   The method for producing pentaerythritol diphosphonate according to claim 12, wherein the organic base compound component to be separated and removed out of the reaction system according to claim 12 is 90 mol% or more with respect to 100 mol% of the used organic base compound.   13. The method according to claim 12, wherein the pentaerythritol diphosphite is not isolated from the solution or suspension of pentaerythritol diphosphite after separation and removal of the organic base compound component out of the reaction system, and it is used for the next reaction c. A process for producing pentaerythritol diphosphonate according to claim 12, wherein   The method for producing pentaerythritol diphosphonate according to claim 4, wherein 180 mol% to 250 mol% of aralkyl alcohol is used with respect to pentaerythritol in the reaction b.   The method for producing pentaerythritol diphosphonate according to claim 4, wherein the halogenated compound used in the reaction c is benzyl bromide.   The method for producing pentaerythritol diphosphonate according to claim 4, wherein the halogenated compound used in the reaction c is benzyl bromide, and the benzyl bromide is used in an amount of 1.5 mol to 3 mol per 1 mol of pentaerythritol.   The method for producing pentaerythritol diphosphonate according to claim 4, wherein the washing solvent used in the washing step contains at least one solvent selected from the group consisting of methanol, ethanol, isopropyl alcohol and acetone. 5. The method for producing pentaerythritol diphosphonate according to claim 4, wherein the pentaerythritol diphosphonate represented by the formula (1) is a dibenzylpentaerythritol diphosphonate represented by the following formula (1-a).

(I) characterized in that the median diameter on a volume basis is 22 μm or less, (ii) the purity is 98% or more, and (iii) the content of the halogenated compound shown in the following formula (2) is 200 ppm or less The flameproofing agent for fibers containing the pentaerythritol diphosphonate shown by following formula (1) made into said.

(Wherein, Ar ¹ and Ar ² may be the same or different and each is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ³ , R ⁴ , R ⁵ and R ⁶ are And each may be the same or different, and is a hydrogen atom, a substituted or unsubstituted aryl group having 6 to 20 carbon atoms, or a saturated or unsaturated linear or branched alkyl group having 1 to 20 carbon atoms.)

(Wherein, Ar ³ is a substituted or unsubstituted aryl group having 6 to 20 carbon atoms. Also, R ⁷ and R ⁸ may be the same or different, and are hydrogen atoms or 1 to 20 carbon atoms. A saturated or unsaturated linear or branched alkyl group, and X is a Br group.)