JPH02247192A - Phosphazene derivative and x-ray shielding material containing the same - Google Patents

Abstract

NEW MATERIAL:The compound of formula I or II {at least one of R<1>-R<6> is X [X is ORa (Ra is hydrocarbon residue containing polymerizable double bond)] and the others are Y [Y is ZRb or ZRc (Z is 0 or NH; Rb and Rc are halo- substituted alkyl, halo-substituted aryl, etc.)] or at least one of R<7>-R<14> is X and the others are Y}. USE:An X-ray shielding material useful as a dental filler, a catheter for X-ray diagnosis, etc. A hardened material having excellent mechanical strength, abrasion resistance and water resistance, low thermal expansion and low polymerization shrinkage can be produced by polymerizing the above compound. PREPARATION:For example, the trimer of a cyclic phosphorous chloride nitride of formula III is made to react successively with a compound containing x-ray shielding element and expressed by formula HZRb or HZRc and a compound containing polymerizable double bond and expressed by formula HORa in a solvent such as toluene in the presence of a tertiary amine.

Description

Detailed Description of the Invention [Industrial Application Field] The present invention relates to a novel phosphazene derivative and an X-ray opaque material containing the same, and more specifically, the above phosphazene derivative has a polymerizable group in its molecule. and Ba, S.
Group 2A elements of the periodic table such as r, Group 3A elements such as La,
4A group elements such as Zr, 5A group elements such as Ta, 2 such as Zn, etc.
A polymerized and cured product obtained from a mixture containing a group B element, a group 4B element such as pb, a group 5B element such as Bi, a halogen such as Br, or a derivative thereof, and a mixture containing the derivative can be obtained from a conventional method. Dental filling materials and crown restorative materials that have extremely high mechanical properties compared to polymers made of monomers, etc., and have high X-ray opacity.

In addition to being able to be used as adhesives and luting materials, X-ray diagnostic catheters, etc., the above polymers have excellent properties such as low wear and shrinkage resistance and water resistance, so they are widely used in general industry. However, it can be used as an X-ray opaque material with high practical value.

[Prior art and problems to be solved by the invention] Composite resins for dental fillings conventionally used mainly contain methyl methacrylate and bis-G.
MA-based monomers are used, but polymers of these monomers not only have poor mechanical properties, but also have large polymerization shrinkage, water absorption, and dissolution, and are said to have low wear resistance. There are drawbacks.

Therefore, as a measure to improve the above-mentioned drawbacks, a large amount of silica powder is mixed into the above-mentioned tsuma, but this alone does not provide X-ray opacity, making it difficult to distinguish between the filled composite resin and the tooth. Can not. That is, when a cavity is filled using this composite resin for filling, the filling does not exhibit X-ray opacity, and clinically, the prognosis of the filling cannot be monitored.

On the other hand, in order to improve the above-mentioned drawbacks, a method has recently been proposed in which a large amount of barium glass powder or a mixture of barium glass powder and silica powder is added to obtain X-ray opacity. However, when barium glass powder or the like is used, its refractive index is significantly different from that of the monomer itself, so the polymer becomes cloudy and the filled composite resin lacks aesthetics. In addition, composite resin for filling using barium glass powder is
Not only is the bond between the monomer and these barium glass powders insufficient, but also there is a large difference in hardness between the matrix made of the polymer part of the monomer and the core part made of powder, resulting in a rough polished part and poor wear resistance. is known to decrease. Furthermore, the biggest problem with these composite resins for filling is that if they are immersed in water for a long period of time, the barium glass mixed in them will hydrolyze and barium ions will be eluted, and the eluted barium ions may be harmful to the human body. In addition to being concerned about the effects, the filler tends to be colored and discolored, and its mechanical properties gradually deteriorate, resulting in poor durability.

That is, if a barium glass powder is mixed with a conventionally used monomer, an X-ray opaque filling composite resin can be obtained, but its physical properties are not clinically satisfactory.

Therefore, researchers are developing polymerizable compounds that have groups or atomic groups with various functions in their molecules and materials containing these compounds as fillers that exhibit X-ray opacity and have good physical properties. .

The present inventor focused on these circumstances, and aimed to develop a compound with a completely different structure from monomers conventionally used, which could fundamentally solve the various drawbacks of conventional composite resins for dental fillings. As a result of various studies, we have completed the present invention.

[Structure of the invention] The phosphazene derivative according to the present invention is a cyclic compound in which the central skeleton of the molecule consists of a nitrogen-phosphorus hetero bond, and various atomic groups or polymerizable functional groups are bonded to this phosphorus atom. It is constructed so that it can perform multiple functions within the same molecule.

In general, compounds consisting of a nitrogen-phosphorus heterobond are carbon-
Compared to compounds consisting of carbon homobonds, it has a large bond energy, a high thermal decomposition point, low molecular rotation, and is rigid. Especially in the case of cyclic compounds,
These properties are so pronounced that these compounds are called inorganic or semi-inorganic compounds.

The phosphazene derivative of the present invention having a phosphazene skeleton, which is a peterocyclic compound as described above, has the general formula [wherein at least one of R1 to R6 is X].

The remainder is Y, or at least one of R7-R14 is X and the rest are Y, X is represented by ORa, and Ra is a hydrocarbon residue having a polymerizable double bond, Y is represented by ZRb or ZRc, Rh and Rc are halo-substituted alkyl, halo-substituted aryl, mono- or dicarboxy-substituted alkyl, or mono- or dicarboxy-substituted aryl, and Rb and Rc are monocarboxy-substituted alkyl or monocarboxy When it is a substituted aryl, it is a group 2A, 3A, 4A, 5A, 2B of the periodic table.
Tribe.

I) fLOゝWhen Rb and Rc are dicarboxy-substituted alkyl or dicarboxy-substituted aryl, the group 2A, 3 Quantity M, Group 4A, Group 5A, Group 2B, 4B
Elements belonging to either group or group 5B are combined, and Z is 0 or NH. The gist is in the point indicated by , and the gist is in that the X-ray opaque material according to the present invention contains the above-mentioned phosphazene derivative monomer or a polymer or copolymer having the monomer as a repeating unit. be. The copolymers include copolymers of the above phosphazene derivative monomer and other types of monomers, and copolymers of the above phosphazene derivative monomer and monomers having different substituents among the phosphazene derivative monomers.

The number of X in the phosphazene derivative represented by the above-mentioned formula (1) or (1゛) is 1 or more, preferably 2 or more, and the number of Y is 4 or less [or 6 or less;
8-membered ring compound represented by °), the same applies hereinafter] is desirable.

The phosphazene derivative according to the present invention is produced by first adding H2Rb or H
A compound containing an X-ray opaque element represented by 2Rc is reacted, and then a compound having a polymerizable double bond represented by HORa is reacted to form 6 of the 3 monomers (or 4 monomers) (or The desired phosphazene derivative can be obtained by substituting the chlorines (8) with any number of groups represented by -ORa and -ZR,b or -ZRc, respectively.

or (provided that at least one of R1 to R6 in the formula, or R7
- At least one of R14 is 10Ra and the rest -
ZRb or -ZRc) The solvent for the above reaction may be a common one, such as benzene, chloroform, cyclohexane, methylene chloride, toluene, xylene, and ether.

Examples include hexane and tetrahydrofuran, preferably benzene and toluene.

On the other hand, in order to accelerate dechlorination, the desired product can be obtained in high yield (85-97%) by adding tertiary amines during the reaction and conducting the reaction at 20-90°C for 2-100 hours. be able to.

In order to polymerize and cure the X-ray opaque material of the invention at room temperature, a peroxide-tertiary amine type polymerization initiator is used. In this case, the amount of peroxide and amine used is preferably 0.1 to 20 parts per 100 parts by weight (hereinafter abbreviated as parts) of the total amount of the X-ray opaque material. In addition, when polymerizing with ultraviolet rays and visible light, −
Numerically, a photosensitizer-amine type initiator is used. The blending amount is 0.05 to 7.0 parts in each case, and the appropriate temperature for polymerization by heating is 60 to 140°C. In addition, numerically, by blending 0.1 to 3.0 parts of a peroxide and a tertiary amine polymerization initiator alone or both to the total amount of reaction raw materials, 60 to 80 Polymerization can be carried out at 5 to 30 minutes at °C.

In the above reaction, the hydrocarbon group having a polymerizable double bond represented by HORa is preferably an alkyl (meth)acrylate having a hydroxyl group,
For example, 2-hydroxypropyl (meth)acrylate, 3-hydroxypropyl (meth)acrylate, 4
-hydroxybutyl (meth)acrylate, 5-hydroxypentyl (meth)acrylate, 6-hydroxyhexyl (meth)acrylate, 7-hydroxyheptyl (meth)acrylate, and 8-hydroxyoctyl (meth)acrylate, and the like are suitable; Particularly recommended is 2-hydroxyethyl (meth)acrylate.

On the other hand, the groups represented by Rb and Rc in H2Rb or HzRc mean halo-substituted alkyl, halo-substituted aryl, mono- or dicarboxy-substituted alkyl, or mono- or dicarboxy-substituted aryl, and Rb and Rc
is monocarboxy-substituted alkyl or monocarboxy-substituted aryl, these are group 2A or 3A of the periodic table.
When Rb and Rc are dicarboxy-substituted alkyl or dicarboxy-substituted aryl, an element of group 2A or group 3A is bonded to the carboxy terminal. The mark indicated by Z is 0 or NH
means.

The alkyl in halo-substituted alkyl is preferably lower alkyl having 1 to 6 carbon atoms, and examples of the lower alkyl include methyl, ethyl propyl, isopropyl, butyl, isobutyl, tertiary butyl, pentyl, neopentyl, and tertiary pentyl. , hexyl and the like. Further, examples of the aryl in halo-substituted aryl include phenyltolyl, xylyl, cumenyl, naphthyl, etc., and these aryls have a group represented by Z and CH2, C2H
It may be bonded via a group such as 4-1C3He. The halogen elements in eight-substituted alkyl and halo-substituted aryl include Br,
The number of halogen elements to be substituted is not particularly limited, but is preferably 1 to 3. By containing the halogen element of Motoshiko Juku et al., the substituent exhibits X-ray opacity. H2Rb or H2Rc containing such eight-substituted alkyl or halo-substituted aryl
The group represented by is preferably a halide containing a hydroxyl group such as 2-bromoethanol, 3-bromoethanol, 3-bromo1-propanol, bromophenol, dibromophenol, tribromophenol, or bromobenzyl alcohol; Examples include halides containing an amino group such as aniline, dibromoaniline, and tribromoaniline.

Next, mono- or dicarboxy-substituted alkyl includes lower alkyl, and the lower alkyl is exemplified by those mentioned above. The aryl in the mono- or dicarboxy-substituted aryl includes the same aryl as in the halo-substituted aryl. These mono- or dicarboxy-substituted alkyls or mono- or dicarboxy-substituted aryls belong to groups 2A, 3A, 4A, and 5A of the periodic table, which impart X-ray opacity to the carboxy terminus.
Group, 2B group, 4B group or 5B group elements are combined,
Group 2A elements include Ba, Sr, etc. Group 3A elements include La, etc. Group 4A photoelements include Zr, Group 5A elements include Ta, Group 2B elements include Zn, Group 4B elements include pb, etc. , B1 etc. are exemplified as the 5B group element.

In addition, since these elements of groups 2A and 3A are divalent elements, they will bond with two carboxyl groups, and when bonding with monocarboxy-substituted alkyl or monocarboxy-substituted aryl, elements of groups 2A and 3A will bond with two carboxyl groups. When bonding to a kyl- or dicarboxy-substituted aryl containing a phosphazene skeleton via an element such as, the bond is made to two carboxyl groups of one substituent.

Examples of compounds in which 2 of H2Rb or H2Rc is O (that is, H2 is a hydroxyl group) include HO(CH2) nC0O
Saturated hydrocarbon carboxylic acid substituted with hydroxy represented by H (n = 1-15), HOC4H4 (CH2)
nC0OH (n=0.1.2), HOCllH, (C
OOH)2゜HOC4B3 (R)COOH(R: 0
Examples include hydroxy-substituted carbocyclic carboxylic acids such as HOCH3), and preferred specific examples include hydroxyacetic acid, hydroxybutyric acid, β-hydroxypropionic acid, 12-hydroxydecanic acid, 1
Hydroxy-substituted alkyl monocarboxylic acids such as 6-hydroxyhexadecanic acid; Hydroxy-substituted alkyl dicarboxylic acids such as malic acid, hydroxyphthalic acid, hydroxygeltal acid: P-hydroxybenzoic acid, P-
Examples include carbocyclic carboxylic acids such as hydroxyphenylacetic acid, P-hydroxyphenylpropionic acid, 4-hydroxyphthalic acid, 2,3-dihydroxydecaninaminic acid, 14-hydroxy-3-methoxybenzoic acid, etc., and these compounds The carboxy terminus of Ba, S
Forms salts with elements such as r and La.

Compounds in which Z of H2Rb or H2Rc is NH (that is, Hz is an amino group) include amino acid compounds, NH (CH
2)nC0OH.

NHCRCOOH, (R:H or alkyl).

Examples include amino-substituted hydrocarbon carboxylic acids such as NH2(CH2)n C0OH (n=1 to s), and preferred specific examples include glycine, β-alanine, γ-aminobutyric acid, and γ-aminobutyric acid.
-aminocaproic acid, P-aminobenzoic acid, L-ornithine, L-lysine, etc., and the carboxy terminals of these compounds form salts with elements such as Ba, Sr, La, etc. in the manner described above.

The basic structure of the phosphazene derivative according to the present invention is as described above, and the X-ray opaque material according to the present invention can be obtained by polymerizing it.

In order to obtain an X-ray opaque material with good mechanical properties after polymerization, the number of polymerizable groups substituted in the phosphazene derivative may be increased.

On the other hand, in order to obtain a material with excellent X-ray opacity, it is sufficient to increase the number of substituted groups having X-ray opacity. On the other hand, the mass absorption coefficients of nitrogen and phosphorus that form the phosphazene skeleton are larger than that of carbon, so the phosphazene derivative exhibits greater X-ray opacity than PMMA or the like due to the skeleton molecule itself.

Since the phosphazene derivative of the present invention has a substitution ratio of an X-ray opaque compound and a polymerizable compound controlled at the molecular level, when the phosphazene derivative is used in a composite resin for dental fillings, it exhibits excellent X-ray resistance. In addition to providing permeability, it also provides excellent mechanical properties and abrasion resistance. In other words, compared to conventional composite resins in which a large amount of barium glass powder is mixed, the polymer strength is greater, the hardness is more uniform, and when immersed in water, no elution of barium or bromine is observed. However, since there is no deterioration of the material, it can be used as a permanent filling material, as well as as a dental restorative material and luting material.
Can be implemented clinically.

In addition, when polymerizing the phosphazene derivative of the present invention, it is also possible to add other polymerizable monomers to the above-mentioned derivative. Such other polymerizable monomers may be monofunctional or polyfunctional, such as methyl acrylate, hydroxyethyl (meth)acrylate, ethylene glycol di(meth)acrylate, di- or tri- and Tetraethylene glycol di(meth)acrylate, glycidyl(meth)acrylate, UDMA, B i sMEPP
Examples include. Further, as vinyl esters of carboxylic acids, vinyl acetate, vinyl butyrate, and vinyl stearate, and as ethylenically unsaturated dicarboxylic acids, fumaric acid, maleic acid, itaconic acid, etc. can be mixed and used.

When the above compound is mixed with the phosphazene derivative,
The amount added varies depending on the viscosity, curing time, and desired physical properties, but usually the phosphazene derivative 100
2 to 80 parts per part can be applied.

On the other hand, in order to improve the properties of the radiopaque material according to the invention, i.e. to increase its wear resistance and hardness, and to reduce its polymerization shrinkage and thermal expansion coefficient, it is possible to treat the surface with silane and titanate compounds. It is desirable to use a mixture of inorganic fillers such as silica, talc, alumina, apatite, glass beads, colloidal silica, barium silicate, barium sulfate, silicon nitride and silicon carbide, or organic fillers such as polymethyl methacrylate with a particle size of 30 μm or less. It will be done. The mixing amount is 0.5 to 8 of the radiopaque material.
Double the amount is recommended. Furthermore, in the above, the phosphazene conductor monomer of the present invention is blended to form an X-ray opaque material, but the phosphazene derivative of the present invention may be polymerized in advance to obtain a cured product, which may be crushed to be applied as an organic filler. The radiopaque material of the present invention can also be obtained by this method.

For clinical use, the X-ray opaque material should be packaged in two forms: one paste or solution contains a common peroxide, and the other paste or powder contains an amine-based polymerization accelerator. The paste or solution and the paste or powder may be kneaded for about 1 minute.

In addition, when the radiopaque material is used as an adhesive or luting material for fillers, the material is dissolved in an organic solvent such as ethanol, chloroform, and ether, and the material is divided into two equal parts to form two packaging forms. As above, peroxide is added to one side and an amine-based polymerization accelerator is added to the other side.
Both of these are mixed and applied to the cavity of a defective tooth. Furthermore, in the case of photopolymerization type, it is in one packaging form,
The composite contains photosensitizers, fillers and the like! I! ,
It is clinically put into practical use in the same way as conventional surgical techniques, by mixing the paste with other ingredients to make a paste, filling it into the cavity of a tooth defect, or as a dental crown restoration material.

[Example] Next, the present invention will be specifically explained with reference to Examples.

(1) A typical X-ray opaque molecular composite material was obtained as follows.

Comparative Example 1 A target product was obtained from 1 mole of phosphorus chloride nitride trimer (hereinafter abbreviated as 3PN) and 6 moles of 2-hydroxyethyl methacrylate (hereinafter abbreviated as HEMA).

Example 1 A target product was obtained from 1 mole of 3PN, 2 moles of barium hydroxyacetate, and 2 moles of HEMA.

Example 2 A target product was obtained from 1 mole of 3PN, 2 moles of barium hydroxybenzoate and 2 moles of HEMA.

Example 3 1 mol of 3PN and 1 mol of β-alanine barium salt and H
The target product was obtained from 4 moles of EMA.

Example 4 A target product was obtained from 1 mol of 3PN, 1 mol of aminobenzoic acid barium salt, and 4 mol of HEMA.

Example 5 1 mole of 3PN and 2 moles of bromoethanol and HEMA
The target product was obtained from 4 mol.

Example 6 1 mole of 3PN and 2 moles of dibromophenol and )(H
The target product was obtained from 4 moles of MA.

Comparative Example 2 A target product was obtained from 1 mole of phosphorus chloride nitride tetramer (hereinafter abbreviated as 4PN) and 8 moles of HEMA.

Example 7 A target product was obtained from 1 mole of 4PN, 2 moles of barium hydroxyacetate and 4 moles of HEMA.

Example 8 A target product was obtained from 1 mol of 4PN, 2 mol of β-aminobenzoic acid barium salt and 4 mol of HEMA.

Example 9 1 mole of 4PN, 4 moles of bromophenol and HEMA
The target product was obtained from 4 mol.

Example 10 1 mole of 4PN and 3 moles of dibromophenol and HEM
The target product was obtained from 5 moles of A5.

Example 11 1 mole of 4PN, 3 moles of bromoaniline and 5 HEMA
The target product was obtained from the mole.

Example 12 A bonding material was obtained using 80 parts of the target product obtained in Example 3 and 20 parts of triethylene glycol dimethacrylate.

Example 13 70 parts of the target product obtained in Example 7, 10 parts of triethylene glycol dimethacrylate, and silica (Irogil R9)
72, particle size 0.016 μm, the same applies hereinafter) to obtain a dental crown restorative material.

Example 14 A bonding material was obtained by combining 80 parts of the target material obtained in Example 10 and 20 parts of HEMA.

Example 15 A filler was obtained using 50 parts of the target material obtained in Example 12, 20 parts of UDMA, and 30 parts of silica.

Example 16 After adding 0.5 part of benzoyl peroxide to a mixture of 80 parts of the target product obtained in Example 9 and 20 parts of silica, 6
Polymerization was carried out by heating at 0°C for 4 hours and then at 120°C for 2 hours. Next, the polymer was ground in a ball mill to produce an organic composite filler.

70 parts of this organic composite filler and target product 3 obtained in Comparative Example 2
A filler was obtained with 0 parts.

Example 17 A mixture of 40 parts of the target product obtained in Example 2, 40 parts of the target product obtained in Example 10, and 20 parts of silica was polymerized in the same manner as in Example 16, and pulverized to produce an organic composite filler. .

A filler was obtained using 60 parts of this organic composite filler and 40 parts of the target material obtained in Example 11.

(2) Polymerization curing method and method for measuring X-ray opacity (aluminum equivalent).

Polymerization and curing of the target X-ray opaque piece A material and the luting material, crown restoration material, and filling material using the material were performed as follows.

In the case of Examples 1 to 3, 6, 7.10 to 12.14 and Comparative Example 1, 100 parts of the target product was divided into two equal parts, 0.25 parts of benzoyl peroxide was added to 50 parts of one, and 50 parts of benzoyl peroxide was added to the other 50 parts.
0.4 part of N-N-dimethyl para-toluidine was added to 0 part, and both were mixed.

The curing time was 2 to 13 minutes.

In the case of Examples 4, 5, 8, 9, 13.15 to 17 and Comparative Example 2, 0.28 part of camphoraquinone, 0.12 part of dibenzyl, and valadimethylaminobenzoin were added to 100 parts of the target product as a photosensitizer. 1.56 parts of ethyl acid was added, and one side of a 3 mm thick sample was irradiated with light for 90 seconds each to polymerize and cure using a visible light polymerization device (Dentsbrey, wavelength 470 nm).

On the other hand, the measurement of X-ray opacity was performed using an X-ray generator (Toshiba DR).
X-191D), tube voltage 60KVp, tube current 10
0 mA, distance between focal films 100 cm, exposure time 1
．． It was set to 5 seconds. The film is X-OMAT TL (:
ff Duck), and the phenomenon was detected using an automatic phenomenon machine (Kodak,
MS) was used.

Film density can be measured using a densitometer (Sakushi, P
DA-15), the optical density was measured at three locations on each specimen on the X-ray film and on each stage of the aluminum step photographed at the same time, and from the film characteristic curve prepared in advance, the relative sensitivity of the film (
flogE) was determined, and the aluminum equivalent (vm) was calculated.

Table 1 shows the aluminum equivalents of Examples and Comparative Examples, and also shows the aluminum equivalents of PMMA, two types of commercially available fillers, and front teeth as reference examples.

As is clear from Comparative Examples 1 and 2 in Table 1, the aluminum equivalent is larger than that of PMMA of Reference Example 1. This is because the mass absorption coefficients of phosphorus and nitrogen are larger than those of carbon, and the effect of the derivative of the present invention having a phosphazene skeleton appears. However, although this level of aluminum equivalent is not satisfactory, the example derivatives in which an X-ray opaque group was introduced into the phosphazene skeleton had a higher aluminum equivalent than Comparative Example 1.2. The aluminum equivalent of the X-ray opaque material may be adjusted depending on the application. For example, the bonding material may have an aluminum equivalent as shown in Examples 12 and 14. In addition, as a dental crown restoration material, Example 13, which has better mechanical properties and a relatively large aluminum equivalent, is suitable, and as a filling material,
Objects of examples larger than the aluminum equivalent of teeth (e.g. Examples 6, 9, 10, 11.1'3.15-17)
is appropriate. This is particularly practical in the cases of Examples 15 to 17, as these exhibit considerably larger aluminum equivalents than conventional filling materials M and P and teeth, so when filling a tooth, it is easy to distinguish between the filling and the tooth. Clinically, it is possible to obtain advantages such as ease of monitoring the filling prognosis.

In addition, further effects of the X-ray opaque material of the present invention are that barium and bromine elements are bonded intermolecularly and
Because it has many polymerizable groups in its molecules, the crosslinking density of the polymer is high, and the above elements will not be eluted even if immersed in water for a long period of time, leading to concerns about harmful effects on the human body and deterioration of physical properties. There's no need to do that. That is, it has the advantage of being durable and can be used as a permanent filler. Furthermore, the cured product of the radiopaque material has many excellent properties, such as being aesthetically pleasing and having a smoother polished surface compared to fillers mixed with barium glass powder. The object of the present invention is to provide a new X-ray opaque material that fundamentally solves the disadvantages of .

[Effects of the Invention] The present invention is constructed as described above, and provides a phosphazene derivative that provides a polymer with excellent X-ray opacity and mechanical properties, and an X-ray opaque material containing the derivative. I was able to provide it.

Claims (3)

[Claims] (1) General formula ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼... (1) or ▲ There are mathematical formulas, chemical formulas, tables, etc. ▼... (1') [In the formula, at least one of R^1 to R^6 one is X and the rest are Y, or at least one of R^7 to R^1^4 is X and the rest are Y, X is represented by ORa, and Ra is a polymerizable double is a hydrocarbon residue having a bond, Y is represented by ZRb or ZRc, Rb and Rc are halo-substituted alkyl, halo-substituted aryl, mono- or dicarboxy-substituted alkyl, or mono- or dicarboxy-substituted aryl, and Rb and Rc is monocarboxy-substituted alkyl or monocarboxy-substituted aryl, these are Groups 2A, 3A, 4A, 5A, 2B of the Periodic Table
When Rb and Rc are dicarboxy-substituted alkyl or dicarboxy-substituted aryl, the group 2A, 3A, or 4A is attached to the carboxy terminal. , 5A group, 2B group, 4B group, and 5B group, and Z is O or NH. ] A phosphazene derivative characterized by the following. (2) An X-ray opaque material containing the phosphazene derivative monomer according to claim (1). (3) An X-ray opaque material containing a polymer or copolymer having the phosphazene derivative monomer of claim (1) as a repeating unit.