JPH0425245B2 - - Google Patents

Description

[Detailed description of the invention]

The present invention relates to dental cement hardeners. In detail, (i) the main chain contains a carbon-carbon bond and there is a carbon bond directly in the molecule.

[Formula] A polymer substance bonded with a group (where X is a hydrogen atom, a metal atom, or a hydrocarbon residue) and (ii) a main chain containing a carbon-carbon bond and directly connected to a carbon atom within the molecule. The present invention relates to a dental cement curing agent comprising a solution containing a polymer substance having -COOH groups bonded thereto. Conventionally, zinc phosphate cement, carboxylate cement, glass ionomer cement, etc. have been used as dental cements, but these cements are not necessarily satisfactory. Zinc phosphate cement in particular has the disadvantage of having almost no adhesive properties, while carboxylate cements can provide adhesive strength but have the disadvantage of reduced mechanical strength. The present inventors have conducted intensive research on dental cement. As a result, we proposed that the mechanical strength of dental cement could be improved by using a polymer with phosphonic acid groups in the liquid component of dental cement instead of polymers with carboxylic acid groups as functional groups. Although it has been possible to improve the mechanical strength of dental cement by using the above-mentioned polymer having phosphonic acid groups as the liquid component, there are cases where it is not possible to obtain satisfactory results in the adhesiveness of dental cement. be. The present inventors have continued to make efforts to develop dental cement, and as a result, a dental cement using a liquid component that is a mixture of the above-mentioned polymer material having phosphonic acid groups and polymer material having carboxyl groups has been developed. We have found a solution to the above technical problem and have completed and proposed the present invention. That is, the present invention provides (i) a main chain containing a carbon-carbon bond and a carbon atom directly connected to a carbon atom in the molecule;

[Formula] A polymer substance bonded with a group (where X is a hydrogen atom, a metal atom, or a hydrocarbon residue);
Contains a carbon bond and directly connects to a carbon atom in the molecule.
This is a dental cement curing agent consisting of a solution containing a polymer substance having COOH groups bonded thereto. The polymer substance used in the present invention has a main chain containing a carbon-carbon bond and a carbon atom directly in the molecule.

As long as two types of polymer substances are used: one in which the [Formula] group is bonded, and the other in which the main chain contains a carbon-carbon bond and a -COOH group is bonded directly to a carbon atom within the molecule. The addition of other known additive components is not particularly limited. That is, the above 2
It is important that a solution containing different types of polymeric substances is used as a hardening agent for dental cement.
It is possible to improve the adhesive strength without impairing the mechanical strength of dental cement. In the dental cement curing agent used in the present invention, the above-mentioned components are present in the molecules of the polymeric substance.

The effect of the present invention cannot be achieved even if a compound in which the [Formula] group and the -COOH group are both bonded together is used alone. The reason for this is that the phosphonic acid group forms a stronger cured product than the carboxylic acid group, but it is thought to have less effect on adhesive properties, and when a carboxylic acid group and a phosphonic acid group exist in the same molecule, the carboxylic acid group also forms. It is presumed that it is in a state where it can hardly work effectively on adhesion. The manufacturing method of the polymeric substance used in the present invention is not particularly limited, but typical methods generally employed in industry are as follows. That is, the carbon atoms in the molecule

For polymeric substances having a [formula] group bonded to them, (i) a method of polymerizing or copolymerizing a monomer having a polymerizable unsaturated bond and a phosphonic acid group or a phosphonic acid ester group; ) A method of introducing a phosphonic acid group or a phosphonic ester group into a polymer substance whose main chain contains a carbon-carbon bond is preferably used. In the method (i) above, monomers having polymerizable unsaturated bonds such as vinylphosphonic acid, allylphosphonic acid, styrenephosphonic acid, or metal or hydrocarbon esters thereof, or copolymerization with these monomers are used. Obtaining the desired product by polymerizing or copolymerizing a mixture with other possible monomers in the presence of a known radical initiator such as azobisisobutyronitrile, benzoyl peroxide, persulfate, etc. I can do it. The other copolymerizable monomer may be used without particular limitation as long as it is copolymerizable with the monomer having a polymerizable unsaturated bond. Representative examples of the copolymerizable monomers that are generally preferably used include those having a carboxylic acid group such as acrylic acid, methacrylic acid, maleic acid, itaconic acid, and fumaric acid; metal salt, carbon number 1~
These include hydrocarbon esters consisting of 10 alkyl groups. These monomers can be used in a wide range of contents; for example, copolymers containing the monomers in a range of 1 to 99 mol%, preferably 85 mol% or less, are the most preferred. Widely used. Among the above monomers, acrylic acid, methacrylic acid, itaconic acid, maleic acid, or their salts and esters are particularly preferably used. In the method (ii) above, a functional group (hereinafter also referred to as an intermediate functional group) capable of introducing a phosphonic acid group or a phosphonic acid ester group by reaction is first added to a polymeric material having a carbon-carbon bond, or the functional group is In this method, a phosphonic acid group or a phosphonic ester group is introduced into a polymeric substance having the following by a post-reaction. For this reaction, a generally widely known method can be employed. Generally, the desired product can be obtained most easily by using a halide as an intermediate functional group. In addition, regarding polymeric substances having a -COOH group bonded to a carbon atom in the molecule, the same applies except that a carboxylic acid group is used instead of the phosphonic acid group or phosphonic ester group explained in (i) and (ii) above. A similar method can be adopted. In this case, the monomer having a polymerizable unsaturated bond and a carboxylic acid group is not particularly limited, and for example, known monomers can be used as they are.
Typical examples of the monomers that are preferably used include acrylic acid, methacrylic acid, and maleic acid. However, as explained above, the most important feature of the present invention is the use of two types of polymer substances, so the monomer having the carboxylic acid group and the monomer having the phosphonic acid group are A polymer substance that has a carboxylic acid group and a phosphonic acid group or a phosphonic acid ester group in the molecule, such as a copolymer, is a polymer substance that has a -COOH group bonded to a carbon atom in the molecule. do not. The polymeric substance of the present invention may have a main chain containing a carbon-carbon bond, but it is generally preferable that the polymeric substance has a main chain containing a carbon-carbon bond. However, the main chain does not have to consist only of carbon-carbon bonds, and may contain different atoms such as oxygen and nitrogen. Such a polymeric substance may be produced by any known method, but preferably used is a polymeric substance obtained by adding a phosphonic acid derivative or a carboxylic acid derivative to a derivative such as polyethyleneimine or polyethylene oxide. directly bonded to the carbon atom of the polymeric substance of the present invention.

[Formula] As mentioned above, X in the group is a hydrogen atom, a metal atom, or a hydrocarbon residue. The metal atom is not particularly limited as long as it can be used in the mouth without any problems; however, for industrial use, the metal atom may include group metals of the periodic table such as sodium and potassium; calcium, magnesium, These include group metals of the periodic table, such as zinc. In addition, hydrocarbon residues are linear, cyclic, or branched and have 1 to 1 carbon atoms.
Thirty aliphatic, cycloaliphatic and aromatic hydrocarbon residues are preferred. The hydrocarbon residue is not particularly limited, but examples of particularly preferred aliphatic hydrocarbon residues include methyl group, ethyl group, propyl group, isopropyl group, vinyl group, allyl group, 2-
Examples of the alicyclic hydrocarbon residue include a cyclohexyl group, cyclohexenyl group, and cyclobentyl group, and examples of the aromatic hydrocarbon residue include a benzyl group, a naphthyl group, and a tolyl group. In addition, the molecular weight of the polymer substance varies depending on the type of polymer substance, but generally it is 1500~
100000 ranges are used, especially 3000~
50,000, more preferably in the range of 5,000 to 20,000. The dental cement curing agent of the present invention is used in the form of a solution containing the polymeric substance. The content of the polymeric substance varies depending on the type and molecular weight of the polymeric substance, the type of powder component used for kneading, etc., and cannot be absolutely limited. Generally, it is often used as an aqueous solution containing 30 to 80%, preferably 50 to 70%, of a polymeric substance. Moreover, any method can be used to mix the above two types of polymeric substances. It can be prepared by adjusting the polymerized liquid to an appropriate concentration and mixing it in a desired ratio. Further, the mixing ratio of the polymer substance having carboxylic acid can be 1 to 99% by weight based on the total polymer, but preferably 10 to 50% by weight, and more preferably 15 to 30% by weight. be. The method for preparing the dental cement curing agent of the present invention is not particularly limited, but generally the polymer substance is added to a solution, such as water, at an appropriate concentration, and used as a solution containing the polymer substance. be. The method of using the dental cement hardener of the present invention in dental cement includes a solution containing the above-mentioned polymeric substance and powder components such as zinc oxide, magnesium oxide, bismuth oxide, calcium oxide, which are known to be used in the dental industry. Alternatively, dental cement may be obtained by mixing and kneading powder components obtained by mixing appropriate amounts of silica, alumina, cryolite, aluminum phosphate, aluminum fluoride, calcium fluoride, etc. and vitrifying the mixture and hardening the mixture. Further, as a method for preparing the dental cement curing agent of the present invention, a solid mixture of a polymer substance and a powder component is prepared, and when manufacturing dental cement, a solution such as water is added to the solid mixture. It can also be added and kneaded. The dental cement curing agent of the present invention is characterized in that it provides dental cement with excellent mechanical strength and high adhesive strength, and it also contributes greatly not only to physical properties but also to operability. big. EXAMPLES In order to explain the present invention more specifically, the present invention will be described below with reference to Examples, but the present invention is not limited to these Examples. The compressive strength in the examples was measured by making a cylindrical sample with a diameter of 6 mm and a length of 12 mm, immersing it in water at 37°C for 24 hours, and then using the ADAS (American Dental Test) method for zinc phosphate cement.
Association Specification). The crosshead speed was measured at 0.5 mm/min. In addition, the bonding strength between bovine tooth enamel and Ni−
Measurements were made using butt adhesion between Cr alloys. Example 1 Put 1 g of pure water and 2 g of ammonium persulfate into a four-necked flask and heat while introducing nitrogen until it reaches 95°C, then add 70 ml of pure water and 17.2 g of ammonium persulfate.
and a solution containing 84 g of vinylphosphonic acid and 40 g of pure water.
ml, isopropyl alcohol 10ml and acrylic acid
A solution containing 300 g was added dropwise at the same time, and the addition was completed in 2 hours. After continuing the reaction for 3 hours, the molecular weight was measured by GPC, and it was found that a polymer with a molecular weight of 16,000 had been produced. This was concentrated to a concentration of 53% (this is referred to as the first solution). Separately, put 670 ml of pure water, 1.2 g of ammonium persulfate, and 120 g of itaconic acid into a four-necked flask, heat while introducing nitrogen, and after reaching 95°C, add 40 ml of pure water.
ml, a solution consisting of 4.7 g of ammonium persulfate;
A solution consisting of 40 ml of pure water, 6 ml of isopropyl alcohol, and 100 g of acrylic acid was added dropwise at the same time, and the addition was completed in 2 hours. After continuing the reaction for another 3 hours, the molecular weight was measured by GPC and found to be 15,000.
polymer was produced. Concentrate this to 53%
(This will be referred to as the second solution). Three solutions were prepared by mixing these solutions and used as a dental cement hardener. That is, the polymers in the second solution were mixed to be 10%, 20%, and 30% of the total polymer, and the total polymer concentration was 53%.
Separately, powder consisting of 93g of zinc oxide, 6g of magnesium oxide, and 1g of calcium fluoride was calcined at 1300℃ and crushed, and then 5g of zinc fluoride and sodium fluoride were added.
0.5g was added and mixed to make a dental cement powder component. The dental cement powder component and the three liquid components mentioned above were mixed and kneaded at a powder/liquid ratio of 1.7 (weight ratio) and subjected to each measurement. Compressive strength was measured according to ADAS, and adhesive strength was measured as follows. That is, after cleaning and wiping the surface polished with #300 emery paper, the above cement mud was filled, and then polished with #300 emery paper.
A clean surface of Ni-Cr alloy was placed on it and a load of 3 kg was applied. After that, it was left for 24 hours at 37°C in an atmosphere of 100% water vapor, and then the tensile strength was measured. The results are shown in Table 1. For comparison, measurements were performed using a solution without the second solution. The results were as shown in Table 1 No. 4.

[Table] Example 2 Silica 29g, alumina 16.5g, cryolite 5g, calcium fluoride 34.3g, aluminum fluoride 5.3g
g and 10 g of aluminum phosphate were melted and vitrified in an electric furnace at 1400° C. for 3 hours, and ground in a ball mill to obtain powder with an average particle size of 20 μm. This was used as a powder component of dental cement, Example 1 (Table 1 No. 2)
The solution obtained in
The mixture was mixed and kneaded with (53% dental cement liquid component) at a powder/liquid ratio of 1.4, and the compressive strength and adhesive strength were measured in the same manner as in Example 1. As a result, the compressive strength was 1020 Kg/cm ² and the adhesive strength was 38 Kg/cm ² . Example 3 5 ml of pure water and 2,2-azobis(2-amidinopropane) dihydrochloride (hereinafter referred to as ABAP) were placed in a three-necked flask.
After heating, a solution of 5 ml of pure water, 0.1 g of ABAP, and 30 g of vinylphosphonic acid placed in a dropping funnel was added dropwise, and the mixture was finished in 2 hours. Thereafter, the reaction was continued for 16 hours and then stopped, and the reaction solution was filtered with a cellulose-based dialysis membrane to remove unreacted monomers and concentrated to obtain 21 g of a 55% aqueous solution. It was confirmed by GPC that it was a polymer with a peak molecular weight of 15,000. Separately, put 45 g of pure water and 0.35 g of ammonium persulfate (APS) in a four-necked flask and heat to 90°C, then add a solution of 0.35 g of APS in 10 g of pure water, 5 g of pure water, 20 g of acrylic acid, and 1 ml of isopropyl alcohol. The addition of the solution was started at the same time, the addition was completed in 1 hour, and the polymerization was continued for an additional 3 hours. After the reaction, it was concentrated to make a 55% solution, and analysis revealed that the molecular weight of polyacrylic acid was 13,000. These two solutions were mixed so that polyacrylic acid accounted for 20% of the total polymer, and the polymer concentration was adjusted to 55% to form a dental cement liquid component. Separately, 93g of zinc oxide, 6g of magnesium oxide,
1 g of calcium fluoride was mixed, baked at 1300℃ for 2 hours, crushed, and further added 0.5 g of sodium fluoride.
g and 4.5 g of sodium tripolyphosphate were added to prepare a dental cement powder component. The ratio of powder components to liquid components
When mixed and kneaded at 1.7 and measured the compressive strength and adhesive strength, the compressive strength was 1070Kg/cm ² and the adhesive strength was 40.
It was Kg/ ^cm2 . For comparison, the same procedure as above was carried out except that polyacrylic acid was not added, and the results were a compressive strength of 1110 Kg/cm ² and an adhesive strength of 23 Kg/cm ² . Example 4 150 ml of pure water and 2,2-azobis(2-amidinopropane) dihydrochloride (ABAP) in a four-neck flask
Add 0.7g and heat to 95℃, add 40ml of pure water,
A solution of 3.4 g of ABAP and 90 g of vinylphosphonic acid (liquid A) and a solution of 15 g of pure water, 7 ml of isopropyl alcohol, and 60 g of acrylic acid (liquid B) were simultaneously dropped, and solution A was finished in 1.5 hours, and then 40 ml of pure water was added.
Complete the dropwise addition of 1.7 g of ABAP solution in 30 minutes, and
Dripping of the liquid was completed in 2 hours. Thereafter, the mixture was reacted for 3 hours and then concentrated to obtain a polymer having a molecular weight of 14,000.
The copolymer solution of acrylic acid and itaconic acid obtained in Example 1 was added to this, and the concentration of the latter was adjusted to 20% of the total polymer, resulting in a polymer concentration of 55%.
This was used as a dental cement liquid component. The dental cement liquid components used were those obtained in Example 1,
The mixture was mixed and kneaded at a powder/liquid ratio of 1.7 and its physical properties were measured. The compressive strength was 1100 kg/cm ² and the adhesive strength was 45 kg/cm ² . For comparison, the test was carried out in the same manner as above except that the copolymer solution of acrylic acid and itaconic acid was not used. As a result, the compressive strength was 1120 Kg/cm ² and the adhesive strength was 20 Kg/cm 2 .
It was warm in ^cm2 . Example 5 In Example 4, a portion of the acrylic acid-vinylphosphonic acid copolymer was converted into a salt to adjust the curing rate. That is, acrylic acid-itaconic acid copolymer was added to 5 mol% of acid groups neutralized with NaOH to give a concentration of 20%, and the polymer concentration was adjusted to 55%, which was used as a dental cement liquid component. The same dental cement liquid components as in Example 4 were used. powder/liquid ratio
When the mixture was mixed and kneaded at 1.7 and the physical properties were measured, the compressive strength was 1060 Kg/cm ² and the adhesive strength was 41 Kg/cm ² . Example 6 30 g of polystyrene powder (molecular weight 11,000) was added to 120 g of phosphorus trichloride and 30 ml of ethylene chloride, and while stirring, 50 g of aluminum chloride was added little by little and reacted at 80° C. for 18 hours. After the reaction, the reaction solution was poured onto ice, then filtered, and the filtrate was dialyzed to separate the polymer and phosphoric acid. The polymer solution obtained above was concentrated and dried to obtain 8 g of the target product, which was dissolved in ice and 53
% solution. The acrylic acid-itaconic acid copolymer liquid obtained in Example 1 was added to this to give a dental cement liquid component of 20%. Using the same dental cement powder ingredients as used in Example 1, powder/
When measured at a liquid ratio of 1.7, the compressive strength was 1040Kg/cm ² ,
The adhesive strength was 43 kg/cm ² . Example 7 100 ml of pure water and 2,2-azobis(2-amidinopropane) dihydrochloride (ABAP) in a four-neck flask
Add 0.5g and heat to 95℃, then add 30ml of pure water,
Solution of ABAP 3.2g, vinylphosphonic acid 80g, vinylphosphonic acid monoethyl ester 15g (liquid A)
A solution of 20 g of pure water, 7 ml of isopropyl alcohol, and 60 g of acrylic acid (solution B) was simultaneously dropped.
Finish the A solution in 1.5 hours, then add 40 ml of pure water.
The dropwise addition of 1.7 g of ABAP solution was completed in 30 minutes, and the dropwise addition of Solution B was completed in 2 hours. After continuing for another 3 hours, it was concentrated to obtain a polymer with a molecular weight of 14,300. The acrylic acid-itaconic acid copolymer obtained in Example 1 was added to this at a concentration of 20% to make the polymer concentration 55%.
It was used as a component of dental cement liquid. Using the same dental cement powder components as in Example 1, physical properties were measured at a powder/liquid ratio of 1.7. Compressive strength 1010Kg/cm ² , adhesive strength 42
It was Kg/ ^cm2 .

Claims (1)

[Claims] 1 (i) The main chain contains a carbon-carbon bond and the group [formula] (wherein X is a hydrogen atom, a metal atom, or a hydrocarbon residue) is directly attached to a carbon atom in the molecule. (ii) a polymer substance whose main chain contains a carbon-carbon bond and which directly connects to a carbon atom in the molecule;
Dental use characterized by comprising a solution containing a polymer substance having a COOH group bonded thereto (excluding those in which a -COOH group and a [Formula] group are both bonded to a carbon atom in the molecule) Cement hardener.