JP7764675B2 - Method for producing polymerizable composition, polymerizable composition, and cured product - Google Patents

Description

The present invention relates to a method for producing a polymerizable composition, a polymerizable composition, and a cured product.

Technologies have been available for imparting antibacterial and other properties to cured products obtained by curing polymerizable compositions. Furthermore, with the recent outbreak of new viral infections, demand for products with antiviral and other properties is increasing.

For example, Patent Document 1 discloses a polymerizable composition containing an ethylenically unsaturated monomer, at least one monomer selected from monofunctional to trifunctional compounds having specific antibacterial properties, and a polymerization initiator.

Japanese Patent Application Publication No. 6-9725

Conventional polymerizable compositions have the problem that when they are given antibacterial or other properties, the appearance of the cured product deteriorates.

The objective of the present invention is to provide a method for producing a polymerizable composition that can impart antibacterial and other properties to a cured product of the polymerizable composition without compromising its appearance.

One aspect of the present invention is a method for producing a polymerizable composition in which a solution of a second polymerizable monomer dissolved in a first solvent is dispersed in a first polymerizable monomer, the method comprising: mixing the first polymerizable monomer, the second polymerizable monomer, and the first solvent; the first polymerizable monomer is a liquid; the second polymerizable monomer is a solid; a surfactant is added when the first polymerizable monomer, the second polymerizable monomer, and the first solvent are mixed; and the first polymerizable monomer is a mixture of ethoxylated bisphenol A dimethacrylate and neopentylglycerol. the second polymerizable monomer is at least one selected from 2-(methacryloyloxy)ethyltrimethylammonium chloride, (3-acrylamidopropyl)trimethylammonium chloride, (2-(acryloyloxy)ethyl)trimethylammonium chloride, and N-(2-acryloyloxyethyl)-N-benzyl-N,N-dimethylammonium chloride; and the first solvent is at least one selected from water, glycerin, and propylene glycol.

According to one aspect of the present invention, it is possible to impart antibacterial and other properties to a cured product of a polymerizable composition without compromising its appearance.

1 is a schematic diagram illustrating a cross section of a polymerizable composition according to an embodiment. FIG. 2 is a schematic diagram showing a cross section of a polymerizable composition according to a comparative example. 1 is an optical microscope photograph of a polymerizable composition according to an embodiment before curing. 1 is an optical microscope photograph of a polymerizable composition according to a comparative example before curing. 1 is a photograph showing the appearance of a polymerizable composition according to an embodiment after curing. 1 is a photograph showing the appearance of a polymerizable composition according to a comparative example after curing.

Next, we will explain how to implement the present invention.

<Method of producing polymerizable composition>
The method for producing a polymerizable composition of the present embodiment is a method for producing a polymerizable composition in which a solution in which a second polymerizable monomer is dissolved in a first solvent is dispersed in a first polymerizable monomer.

The method for producing a polymerizable composition of this embodiment includes a step of mixing a first polymerizable monomer, a second polymerizable monomer, and a first solvent (hereinafter referred to as the mixing step).

In the method for producing a polymerizable composition of this embodiment, the first polymerizable monomer is liquid, and the second polymerizable monomer is solid. For example, the first polymerizable monomer is liquid at room temperature and normal pressure, and the second polymerizable monomer is solid at room temperature and normal pressure.

If the first polymerizable monomer and the second polymerizable monomer are mixed without using the first solvent, it is difficult to control the particle size of the second polymerizable monomer, and the second polymerizable monomer cannot be uniformly localized within the first polymerizable monomer. As a result, the appearance and strength of the cured product of the polymerizable composition are reduced. Furthermore, if the first polymerizable monomer and the second polymerizable monomer are mixed without using the first solvent, the second polymerizable monomer functions as a filler with a different polarity from the first polymerizable monomer, significantly increasing the viscosity of the polymerizable composition and reducing the workability of the polymerizable composition.

On the other hand, by mixing the first polymerizable monomer, the second polymerizable monomer, and the first solvent, the second polymerizable monomer can be uniformly localized in the polymerizable composition. As a result, the cured product of the polymerizable composition can be imparted with the functionality or performance derived from the second polymerizable monomer, while improving the appearance and strength of the cured product of the polymerizable composition.

For example, if the second polymerizable monomer has a functional group that exhibits antibacterial properties (hereinafter referred to as an antibacterial group), antibacterial properties can be imparted to the cured product of the polymerizable composition. Furthermore, if the second polymerizable monomer has a functional group that exhibits antiviral properties (hereinafter referred to as an antiviral group), antiviral properties can be imparted to the cured product of the polymerizable composition.

The mass ratio of the first solvent to the second polymerizable monomer is preferably 0.01 to 5, and more preferably 0.1 to 2. When the mass ratio of the first solvent to the second polymerizable monomer is 0.01 or more, the stability of the second polymerizable monomer when dissolved in the first solvent is improved, and when it is 5 or less, the mechanical strength of the cured product of the polymerizable composition is improved.

The mass ratio of the first polymerizable monomer to the total amount of the second polymerizable monomer and the first solvent is preferably 0.1 to 100, and more preferably 0.5 to 50. When the mass ratio of the first polymerizable monomer to the total amount of the second polymerizable monomer and the first solvent is 0.1 or more, the mechanical strength of the cured product of the polymerizable composition is improved, and when it is 100 or less, the performance derived from the second polymerizable monomer of the cured product of the polymerizable composition is improved.

In this embodiment, a surfactant may or may not be added when mixing the first polymerizable monomer, the second polymerizable monomer, and the first solvent.

The surfactant is not particularly limited as long as it can improve the dispersibility of the solution, but examples include sodium lauryl sulfate and glycerin fatty acid esters. These surfactants may be used alone or in combination of two or more.

In this embodiment, it is preferable to add and knead other components such as a photopolymerization initiator, a tertiary amine, a polymerization inhibitor, and a filler during the mixing process.

The other components may be added to the first polymerizable monomer, the second polymerizable monomer, and/or the first solvent before they are mixed in the mixing step. Alternatively, the other components may be added after the first polymerizable monomer, the second polymerizable monomer, and the first solvent are mixed in the mixing step.

The mixing step may include a step of dissolving the second polymerizable monomer in the first solvent to obtain a solution, and a step of mixing the solution with the first polymerizable monomer.

By mixing the first polymerizable monomer with a solution in which the second polymerizable monomer is dissolved in the first solvent, the second polymerizable monomer can be more uniformly localized in the polymerizable composition. As a result, the cured product of the polymerizable composition can be imparted with functionality or performance derived from the second polymerizable monomer, while further improving the appearance and strength of the cured product of the polymerizable composition.

For example, if the second polymerizable monomer has an antibacterial group, antibacterial properties can be imparted to the cured product of the polymerizable composition. Furthermore, if the second polymerizable monomer has an antiviral group, antiviral properties can be imparted to the cured product of the polymerizable composition.

When the first solvent is water, the second polymerizable monomer may be allowed to absorb moisture from the atmosphere, thereby dissolving the second polymerizable monomer in water.

Methods for mixing the first polymerizable monomer with a solution in which the second polymerizable monomer is dissolved in the first solvent include, for example, kneading the solution with the first polymerizable monomer using a mortar, mixing the solution with the first polymerizable monomer using a magnetic stirrer, and mixing the solution with the first polymerizable monomer using a stirrer with stirring blades.

In this embodiment, a surfactant may or may not be added when mixing the solution with the first polymerizable monomer.

The surfactant is not particularly limited as long as it can improve the dispersibility of the solution, but examples include sodium lauryl sulfate and glycerin fatty acid esters. These surfactants may be used alone or in combination of two or more.

In this embodiment, when mixing the first polymerizable monomer with a solution in which the second polymerizable monomer is dissolved in the first solvent, it is preferable to add other components such as a photopolymerization initiator, a tertiary amine, a polymerization inhibitor, and a filler and then knead them together.

Note that other components may be added to the solution and/or the first polymerizable monomer before mixing. Alternatively, other components may be added after mixing the solution and the first polymerizable monomer.

The mixing step may include the steps of: dissolving at least a portion of the first polymerizable monomer and the second polymerizable monomer in a second solvent to obtain a solution; distilling off the second solvent from the solution to obtain a dispersion in which the second polymerizable monomer is dispersed in at least a portion of the first polymerizable monomer; and mixing the dispersion with the first solvent.

In this embodiment, by mixing a dispersion in which a second polymerizable monomer is dispersed in a first polymerizable monomer with the first solvent, the second polymerizable monomer can be more uniformly localized in the polymerizable composition. As a result, the cured product of the polymerizable composition can be imparted with functionality or performance derived from the second polymerizable monomer, while further improving the appearance and strength of the cured product of the polymerizable composition.

For example, if the second polymerizable monomer has an antibacterial group, antibacterial properties can be imparted to the cured product of the polymerizable composition. Furthermore, if the second polymerizable monomer has an antiviral group, antiviral properties can be imparted to the cured product of the polymerizable composition.

Here, if a portion of the first polymerizable monomer is used when obtaining the solution, the dispersion is obtained and then mixed with the remainder of the first polymerizable monomer. The timing of mixing the dispersion with the remainder of the first polymerizable monomer is not particularly limited, but it is preferable to mix the remainder of the first polymerizable monomer when mixing the dispersion with the first solvent.

When obtaining the solution, the mass ratio of the second polymerizable monomer to at least a portion of the first polymerizable monomer is preferably 0.01 to 100, and more preferably 0.05 to 50. When the mass ratio of the first polymerizable monomer to the second polymerizable monomer is 0.01 to 100, the dispersion state of the dispersion obtained by distilling off the second solvent from the solution is good.

The content of the second solvent in the solution is not particularly limited, but is preferably, for example, 10% by mass or more and 99% by mass or less. If the content of the second solvent in the solution is 10% by mass or more, the dissolution stability of the polymerizable monomer is improved, and if it is 99% by mass or less, the second solvent can be easily removed by distillation from the solution.

Methods for mixing the dispersion liquid and the first solvent include, for example, stirring the dispersion liquid and the first solvent, mixing the dispersion liquid and the first solvent using a magnetic stirrer, and mixing the dispersion liquid and the first solvent using a stirrer with stirring blades.

In this embodiment, a surfactant may or may not be added when mixing the dispersion liquid and the first solvent.

The surfactant is not particularly limited as long as it can improve the dispersibility of the solution, but examples include sodium lauryl sulfate and glycerin fatty acid esters. These surfactants may be used alone or in combination of two or more.

In this embodiment, after mixing the dispersion liquid with the first solvent, it is preferable to add other components such as a photopolymerization initiator, a tertiary amine, a polymerization inhibitor, and a filler, and then knead the mixture.

Note that other components may be added to the dispersion liquid and/or the first solvent before mixing. Also, other components may be added when mixing the dispersion liquid and the first solvent.

<First Polymerizable Monomer>
The first polymerizable monomer is liquid at room temperature and pressure and is insoluble in the first solvent.

The first polymerizable monomer is preferably a (meth)acrylate, and more preferably a polyfunctional (meth)acrylate having two or more (meth)acryloyloxy groups.

Examples of the first polymerizable monomer include ethoxylated bisphenol A dimethacrylate, neopentyl glycol dimethacrylate, urethane dimethacrylate, glycerin dimethacrylate, and triethylene glycol dimethacrylate. These first polymerizable monomers may be used alone or in combination of two or more.

<Second Polymerizable Monomer>
The second polymerizable monomer is solid at room temperature and normal pressure, soluble in the first solvent, and insoluble in the first polymerizable monomer.

The second polymerizable monomer is preferably a (meth)acrylate, and more preferably a monofunctional (meth)acrylate having one (meth)acryloyloxy group.

The second polymerizable monomer preferably has a functional group that exhibits at least one of antibacterial and antiviral properties. A functional group that exhibits at least one of antibacterial and antiviral properties refers to a case where one functional group exhibits both antibacterial and antiviral properties, or a case where one functional group exhibits either an antibacterial group or an antiviral group. Furthermore, a functional group that exhibits antibacterial and antiviral properties also includes a case where the functional group has both an antibacterial functional group and an antiviral functional group.

Functional groups that exhibit at least one of antibacterial and antiviral properties are not particularly limited, but examples include quaternary ammonium bases. Quaternary ammonium bases can function as both antibacterial and antiviral groups.

Examples of second polymerizable monomers having a functional group exhibiting at least one of antibacterial and antiviral properties include monofunctional polymerizable monomers such as 2-(methacryloyloxy)ethyltrimethylammonium chloride, (3-acrylamidopropyl)trimethylammonium chloride, (2-(acryloyloxy)ethyl)trimethylammonium chloride, N-(2-acryloyloxyethyl)-N-benzyl-N,N-dimethylammonium chloride, dimethylaminopropylacrylamide methyl chloride quaternary salt, dimethylaminoethyl acrylate methyl chloride quaternary salt, and dimethylaminoethyl acrylate benzyl chloride quaternary salt, as well as those represented by the following chemical formula:

These second polymerizable monomers having a functional group exhibiting at least one of antibacterial and antiviral properties may be used alone or in combination of two or more kinds.

Examples of the second polymerizable monomer that does not have either an antibacterial group or an antiviral group include phenoxyethylene glycol methacrylate and dimethylaminoethyl methacrylate.

These second polymerizable monomers, which have neither an antibacterial group nor an antiviral group, may be used alone or in combination of two or more types.

<First Solvent>
Examples of the first solvent include water, glycerin, propylene glycol, ethylene glycol, polyethylene glycol having an average molecular weight of 1200 or less, butylene glycol, etc. These first solvents may be used alone or in combination of two or more.

<Second Solvent>
Examples of the second solvent include organic solvents such as ethanol, acetone, hexane, etc. These second solvents may be used alone or in combination of two or more.

<Photopolymerization initiator>
Examples of the photopolymerization initiator include camphorquinone, phenylbis(2,4,6-trimethylbenzoyl)phosphine oxide, 2,4,6-trimethylbenzoyldiphenylphosphine oxide, benzil ketal, diacetyl ketal, benzil dimethyl ketal, benzil diethyl ketal, benzil bis(2-methoxyethyl)ketal, 4,4'-dimethyl(benzil dimethyl ketal), anthraquinone, 1-chloroanthraquinone, 2-chloroanthraquinone, 1,2-benzanthraquinone, 1-hydroxyanthraquinone, 1-methylanthraquinone, 2-ethylanthraquinone, and 1-bromoanthraquinone. Non, thioxanthone, thioxanthone, 2-isopropylthioxanthone, 2-nitrothioxanthone, 2-methylthioxanthone, 2,4-dimethylthioxanthone, 2,4-diethylthioxanthone, 2,4-diisopropylthioxanthone, 2-chloro-7-trifluoromethylthioxanthone, thioxanthone-10,10-dioxide, thioxanthone-10-oxide, benzoin methyl ether, benzoin ethyl ether, benzoin isopropyl ether, benzoin isobutyl ether, benzophenone, bis(4-dimethylaminophenyl)ketone, 4,4'-bis(diethylamino)benzophenone, etc. These photopolymerization initiators may be used alone or in combination of two or more.

<Tertiary amine>
The tertiary amine may be either a tertiary aliphatic amine or a tertiary aromatic amine, but is preferably a tertiary aromatic amine, and more preferably an alkyl p-dialkylaminobenzoate.

Examples of tertiary aliphatic amines include N,N-dimethylaminoethyl methacrylate and triethanolamine.

Examples of alkyl p-dialkylaminobenzoates include methyl p-dimethylaminobenzoate, ethyl p-dimethylaminobenzoate, propyl p-dimethylaminobenzoate, amyl p-dimethylaminobenzoate, isoamyl p-dimethylaminobenzoate, ethyl p-diethylaminobenzoate, and propyl p-diethylaminobenzoate.

Examples of tertiary aromatic amines other than alkyl p-dialkylaminobenzoates include 7-dimethylamino-4-methylcoumarin, N,N-dimethylaniline, N,N-dibenzylaniline, N,N-dimethyl-p-toluidine, N,N-diethyl-p-toluidine, N,N-bis(2-hydroxyethyl)-p-toluidine, N,N,2,4,6-pentamethylaniline, N,N,2,4-tetramethylaniline, and N,N-diethyl-2,4,6-trimethylaniline.

These tertiary amines may be used alone or in combination of two or more.

<Polymerization inhibitor>
Examples of the polymerization inhibitor include dibutylhydroxytoluene (2,6-di-tert-butyl-p-cresol), 6-tert-butyl-2,4-xylenol, etc. These polymerization inhibitors may be used alone or in combination of two or more.

<Filler>
Examples of the filler include silicic acid anhydride powder, fumed silica, alumina powder, glass powder (e.g., barium glass powder, fluoroaluminosilicate glass powder), etc. These fillers may be used alone or in combination of two or more.

The filler may also be treated with a surface treatment agent such as a silane coupling agent.

<Polymerizable composition>
The polymerizable composition of this embodiment includes a first polymerizable monomer and a solution of the second polymerizable monomer dissolved in a first solvent dispersed therein, where the first polymerizable monomer is a liquid and the second polymerizable monomer is a solid.

The polymerizable composition of this embodiment can be produced by the above-described method for producing a polymerizable composition. The first polymerizable monomer used in the polymerizable composition of this embodiment can be the same as the first polymerizable monomer used in the above-described method for producing a polymerizable composition.

The second polymerizable monomer used in the polymerizable composition of this embodiment can be the same as the second polymerizable monomer used in the method for producing a polymerizable composition described above. The first solvent used in the polymerizable composition of this embodiment can be the same as the first solvent used in the method for producing a polymerizable composition described above.

The content of the first polymerizable monomer in the polymerizable composition of this embodiment is not particularly limited, but is preferably 1% by mass or more and 99.9% by mass or less, more preferably 1.5% by mass or more and 79% by mass or less, and even more preferably 2% by mass or more and 49% by mass or less. When the content of the first polymerizable monomer in the polymerizable composition of this embodiment is 1% by mass or more, the mechanical strength of the cured product of the polymerizable composition is improved, and when it is 99.9% by mass or less, the function or performance derived from the second polymerizable monomer of the cured product of the polymerizable composition is improved.

The content of the second polymerizable monomer in the polymerizable composition of this embodiment is not particularly limited, but is preferably 0.01% by mass or more and 99% by mass or less, more preferably 0.02% by mass or more and 79% by mass or less, and even more preferably 0.03% by mass or more and 49% by mass or less. When the content of the second polymerizable monomer in the polymerizable composition of this embodiment is 0.01% by mass or more, the function or performance derived from the second polymerizable monomer of the cured product of the polymerizable composition is improved, and when it is 99% by mass or less, the mechanical strength of the cured product of the polymerizable composition is improved.

The content of the first solvent in the polymerizable composition of this embodiment is not particularly limited, but is preferably, for example, 0.01% by mass or more and 40% by mass or less, more preferably 0.02% by mass or more and 35% by mass or less, and even more preferably 0.03% by mass or more and 30% by mass or less. When the content of the first solvent in the polymerizable composition of this embodiment is 0.01% by mass or more, the function or performance derived from the second polymerizable monomer of the cured product of the polymerizable composition is improved, and when it is 40% by mass or less, the mechanical strength of the cured product of the polymerizable composition is improved.

In the polymerizable composition of this embodiment, the second polymerizable monomer preferably has a functional group that exhibits at least one of antibacterial and antiviral properties. The second polymerizable monomer having a functional group that exhibits at least one of antibacterial and antiviral properties can be the second polymerizable monomer used in the above-mentioned method for producing a polymerizable composition. Specifically, the functional group that exhibits at least one of antibacterial and antiviral properties used in the second polymerizable monomer can be a quaternary ammonium base or the like used in the above-mentioned method for producing a polymerizable composition.

The uses of the polymerizable composition of this embodiment are not particularly limited. For example, the polymerizable composition of this embodiment is used in products in fields requiring antibacterial, antiviral, and other properties, and is particularly suitable for use as a dental polymerizable composition in the dental field.

Examples of dental polymerizable compositions include dental composite resins, dental cements, denture base resins, and general-purpose dental resins. Of these, dental composite resins are preferred.

<Cured product>
The cured product obtained by curing the polymerizable composition of this embodiment can be a cured product obtained by curing the polymerizable composition obtained by the method for producing a polymerizable composition of this embodiment described above. Furthermore, the cured product obtained by curing the polymerizable composition of this embodiment can be a cured product obtained by curing the polymerizable composition of this embodiment described above. Here, the cured product obtained by curing the polymerizable composition is a cured product of the polymerizable composition obtained by polymerizing and curing the polymerizable composition.

Specifically, when the second polymerizable monomer in the polymerizable composition has a functional group that exhibits at least one of antibacterial and antiviral properties, antibacterial and/or antiviral properties can be imparted to a cured product obtained by curing the polymerizable composition.

The uses of the cured product obtained by curing the polymerizable composition of this embodiment are not particularly limited. For example, the cured product of this embodiment is used in products in fields requiring antibacterial, antiviral, and other properties, and is particularly suitable for use in the dental field as a cured product obtained by curing a dental polymerizable composition. Furthermore, a cured product obtained by curing a dental polymerizable composition can be used, for example, in dental resin blocks.

The present embodiment will be further explained below using examples. Note that the present invention is not limited to these examples.

First, dental composite resins were prepared using examples of the polymerizable composition of this embodiment and evaluated.

<Example 1-1>
4 g of 2-(methacryloyloxy)ethyltrimethylammonium chloride (hereinafter referred to as MTMAC) as a second polymerizable monomer and 1 g of distilled water as a first solvent were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of MTMAC.

7 g of ethoxylated bisphenol A dimethacrylate (hereinafter referred to as BisMEPP) and 6 g of neopentyl glycol dimethacrylate (hereinafter referred to as NPG) were mixed as the first polymerizable monomer, followed by the addition of 20 g of fluoroaluminosilicate glass powder with a median diameter of 0.4 μm that had been surface-treated with 3-glycidyloxytrimethoxysilane, 0.02 g of (±)-camphorquinone, 0.05 g of ethyl p-dimethylaminobenzoate, and 2 g of an aqueous solution of MTMAC. The mixture was then kneaded in an agate mortar until a uniform paste was obtained, yielding a dental composite resin.

<Example 1-2>
8 g of MTMAC and 2 g of distilled water were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of MTMAC.

4.5 g of BisMEPP and 3.5 g of NPG were mixed, followed by the addition of 20 g of fluoroaluminosilicate glass powder with a median diameter of 0.4 μm that had been surface-treated with 3-glycidyloxytrimethoxysilane, 0.02 g of (±)-camphorquinone, 0.05 g of ethyl p-dimethylaminobenzoate, and 7 g of an aqueous solution of MTMAC. The mixture was then kneaded in an agate mortar until a uniform paste was formed, yielding a dental composite resin.

<Example 1-3>
4 g of MTMAC and 1 g of distilled water were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of MTMAC.

7.5 g of BisMEPP and 7 g of NPG were mixed, followed by the addition of 20 g of fluoroaluminosilicate powder with a median diameter of 0.4 μm that had been surface-treated with 3-glycidyloxytrimethoxysilane, 0.02 g of (±)-camphorquinone, 0.05 g of ethyl p-dimethylaminobenzoate, and 0.5 g of an aqueous solution of MTMAC. The mixture was then kneaded in an agate mortar until a uniform paste was obtained, yielding a dental composite resin.

<Example 1-4>
After weighing 4 g of MTMAC onto a weighing dish, the dish was left to stand for 3.5 hours at a temperature of 23°C and a relative humidity of 50% to allow the MTMAC to absorb moisture from the environment, thereby obtaining an aqueous solution of MTMAC. At this time, the mass of the weighing dish had increased by 1 g.

A dental composite resin was obtained in the same manner as in Example 1-1, except that the obtained aqueous solution of MTMAC was used.

<Example 1-5>
5 g of MTMAC and 5 g of glycerin were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain a solution of MTMAC in glycerin.

A dental composite resin was obtained in the same manner as in Example 1-1, except that a glycerin solution of MTMAC was used instead of an aqueous solution of MTMAC.

<Example 1-6>
5 g of MTMAC and 5 g of propylene glycol were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain a propylene glycol solution of MTMAC.

After mixing 7 g of BisMEPP and 6 g of NPG, 20 g of fluoroaluminosilicate glass powder with a median diameter of 0.4 μm that had been surface-treated with 3-glycidyloxytrimethoxysilane, 0.02 g of (±)-camphorquinone, 0.05 g of ethyl p-dimethylaminobenzoate, 0.01 g of sodium dodecyl sulfate (hereinafter referred to as SDS) as a surfactant, and 2 g of a propylene glycol solution of MTMAC were added, and the mixture was kneaded in an agate mortar until a uniform paste was obtained, yielding a dental composite resin.

<Example 1-7>
4 g of (3-acrylamidopropyl)trimethylammonium chloride (hereinafter referred to as AATMAC) as a second polymerizable monomer and 1 g of distilled water were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of AATMAC.

A dental composite resin was obtained in the same manner as in Example 1-1, except that an aqueous solution of AATMAC was used instead of an aqueous solution of MTMAC.

<Example 1-8>
4 g of (2-(acryloyloxy)ethyl)trimethylammonium chloride (hereinafter referred to as ATMAC) as a second polymerizable monomer and 1 g of distilled water were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of ATMAC.

A dental composite resin was obtained in the same manner as in Example 1-1, except that an aqueous solution of ATMAC was used instead of an aqueous solution of MTMAC.

<Example 1-9>
4 g of N-(2-acryloyloxyethyl)-N-benzyl-N,N-dimethylammonium chloride (hereinafter referred to as ABDMAC) as a second polymerizable monomer and 1 g of distilled water were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of ABDMAC.

A dental composite resin was obtained in the same manner as in Example 1-1, except that an aqueous solution of ABDMAC was used instead of an aqueous solution of MTMAC.

Example 2
7 g of BisMEPP and 6 g of NPG as a first polymerizable monomer, 1.6 g of MTMAC as a second polymerizable monomer, and 0.4 g of distilled water as a first solvent were mixed, and then 20 g of fluoroaluminosilicate glass powder having a median diameter of 0.4 μm and having been surface-treated with 3-glycidyloxytrimethoxysilane, 0.02 g of (±)-camphorquinone, and 0.05 g of ethyl p-dimethylaminobenzoate were added, and the mixture was kneaded in an agate mortar until a uniform paste was obtained, thereby obtaining a dental composite resin.

Example 3
To 200 mL of ethanol as a second solvent, 6 g of NPG as a first polymerizable monomer and 4 g of MTMAC as a second polymerizable monomer were added, and then the mixture was stirred with a stirrer for 5 hours while being heated to 50°C in a water bath to obtain an ethanol solution of MTMAC/NPG. Next, ethanol was distilled off under reduced pressure from the ethanol solution of MTMAC/NPG using an evaporator to obtain an NPG dispersion of MTMAC.

1 g of distilled water (first solvent) was added to 10 g of the MTMAC NPG dispersion, and the mixture was stirred with a stirrer to obtain an emulsion in which the MTMAC aqueous solution was dispersed in the NPG.

7 g of BisMEPP and 3 g of NPG were mixed as the first polymerizable monomer, followed by the addition of 20 g of fluoroaluminosilicate glass powder with a median diameter of 0.4 μm that had been surface-treated with 3-glycidyloxytrimethoxysilane, 0.02 g of (±)-camphorquinone, 0.05 g of ethyl p-dimethylaminobenzoate, and 5 g of emulsion. The mixture was then kneaded in an agate mortar until a uniform paste was obtained, yielding a dental composite resin.

<Comparative Example 1>
After mixing 7 g of BisMEPP and 3 g of NPG as a first polymerizable monomer, 15 g of fluoroaluminosilicate glass powder having a median diameter of 0.4 μm and having been surface-treated with 3-glycidyloxytrimethoxysilane, 0.02 g of (±)-camphorquinone, 0.05 g of ethyl p-dimethylaminobenzoate, 2 g of MTMAC as a second polymerizable monomer, and 3 g of NPG as a first polymerizable monomer were added, and the mixture was kneaded in an agate mortar until a uniform paste was obtained, thereby obtaining a dental composite resin.

Next, the appearance, strength, antibacterial properties, and durability of antibacterial properties of the hardened dental composite resin (test specimen) were evaluated.

<Appearance of the hardened product>
The surface of a cured body having a diameter of 15 mm and a thickness of 1 mm obtained by photopolymerizing a dental composite resin using a dental light irradiator was polished with water-resistant abrasive paper #4000 under water, and the presence or absence of irregularities on the polished surface was then visually confirmed to evaluate the appearance of the cured body.

The criteria for judging the appearance of the hardened body are as follows:

Excellent: There are no irregularities on the polished surface of the cured product, and the cured product has a good appearance. Poor: There are irregularities on the polished surface of the cured product, and the cured product has a poor appearance.

<Strength of hardened body>
The strength of the cured body was evaluated in accordance with JIS T 6514:2015 Dental restorative composite resin bending test.

The criteria for judging the strength of the hardened body are as follows:

Excellent: When the bending strength of the hardened product is 100 MPa or more. Good: When the bending strength of the hardened product is 80 MPa or more and less than 100 MPa. Poor: When the bending strength of the hardened product is less than 80 MPa.

<Antibacterial>
The antibacterial properties of the test pieces were evaluated in accordance with JIS Z 2801:2012 Antibacterial processed products - Antibacterial test method/antibacterial effect.

S. mutans was used as the test bacterium.

In addition, 1/10 BHI medium was used instead of 1/500 bouillon medium as the medium for seeding the test bacteria onto the test specimens, in order to ensure that the antibacterial properties would be exerted even under more severe conditions.

The criteria for determining the antibacterial properties of test specimens are as follows:

Excellent: When the antibacterial activity value of the test piece is 4 or more. Good: When the antibacterial activity value of the test piece is 2 or more and less than 4. Poor: When the antibacterial activity value of the test piece is less than 2.

<Sustained antibacterial properties>
The test specimen was immersed in a neutral phosphate buffer solution for one month, and then the antibacterial properties of the test specimen were evaluated in the same manner as above.

Table 1 shows the evaluation results for the appearance, strength, antibacterial activity, and durability of antibacterial activity of the cured dental composite resin.

Table 1 shows that the dental composite resins of Examples 1-1 to 1-9, 2, and 3 have excellent cured body appearance, strength, antibacterial properties, and durability of antibacterial properties.

In contrast, the dental composite resin of Comparative Example 1 was produced without using the first solvent, and therefore the cured product had poor appearance and strength.

Next, plastic pieces were prepared as test specimens and evaluated for examples of cured products obtained by curing the polymerizable composition of this embodiment.

Example 4
4 g of 2-(methacryloyloxy)ethyltrimethylammonium chloride (hereinafter referred to as MTMAC) as a second polymerizable monomer and 1 g of distilled water as a first solvent were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of MTMAC.

14 g of ethoxylated bisphenol A dimethacrylate (hereinafter referred to as BisMEPP) and 12 g of neopentyl glycol dimethacrylate (hereinafter referred to as NPG) were mixed as a first polymerizable monomer, and then 0.04 g of (±)-camphorquinone, 0.1 g of ethyl p-dimethylaminobenzoate, and 4 g of an aqueous solution of MTMAC were added thereto, and the mixture was kneaded in an agate mortar until it became a uniform paste. The mixture was then irradiated with light from an LED having a wavelength of 365 to 465 ^nm and an irradiation intensity of 1200 mW/cm for 5 minutes to polymerize, thereby obtaining plastic pieces.

Example 5
16 g of MTMAC and 4 g of distilled water were added to a bottle with a lid, and then stirred with a stirrer to obtain an aqueous solution of MTMAC.

After mixing 18 g of BisMEPP and 14 g of NPG, 0.04 g of (±)-camphorquinone, 0.1 g of ethyl p-dimethylaminobenzoate, and 14 g of an aqueous solution of MTMAC were added, and the mixture was kneaded in an agate mortar until it became a uniform paste. The mixture was then irradiated with light from an LED with a wavelength of 365 to 465 nm and an irradiation intensity of 1200 mW/ ^cm for 5 minutes to polymerize and obtain plastic pieces.

Example 6
4 g of MTMAC and 1 g of distilled water were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of MTMAC.

After mixing 15 g of BisMEPP and 14 g of NPG, 0.04 g of (±)-camphorquinone, 0.1 g of ethyl p-dimethylaminobenzoate, and 1 g of an aqueous solution of MTMAC were added, and the mixture was kneaded in an agate mortar until it became a uniform paste. The mixture was then irradiated with light from an LED with a wavelength of 365 to 465 nm and an irradiation intensity of 1200 mW/ ^cm for 5 minutes to polymerize and obtain plastic pieces.

Example 7
After weighing 4 g of MTMAC onto a weighing dish, the dish was left to stand for 3.5 hours at a temperature of 23°C and a relative humidity of 50% to allow the MTMAC to absorb moisture from the environment, thereby obtaining an aqueous solution of MTMAC. At this time, the mass of the weighing dish had increased by 1 g.

Except for using the resulting aqueous solution of MTMAC, polymerization was carried out in the same manner as in Example 1 to obtain plastic pieces.

Example 8
5 g of MTMAC and 5 g of glycerin were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain a solution of MTMAC in glycerin.

Plastic pieces were obtained in the same manner as in Example 4, except that a glycerin solution of MTMAC was used instead of an aqueous solution of MTMAC.

Example 9
5 g of MTMAC and 5 g of propylene glycol were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain a propylene glycol solution of MTMAC.

After mixing 14 g of BisMEPP and 12 g of NPG, 0.04 g of (±)-camphorquinone, 0.1 g of ethyl p-dimethylaminobenzoate, 0.02 g of sodium dodecyl sulfate (hereinafter referred to as SDS) as a surfactant, and 4 g of a propylene glycol solution of MTMAC were added, and the mixture was kneaded in an agate mortar until it became a uniform paste. The mixture was then irradiated with light from an LED with a wavelength of 365 to 465 nm and an irradiation intensity of 1200 mW/ ^cm for 5 minutes to polymerize and obtain plastic pieces.

Example 10
4 g of (3-acrylamidopropyl)trimethylammonium chloride (hereinafter referred to as AATMAC) as a second polymerizable monomer and 1 g of distilled water were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of AATMAC.

Plastic pieces were obtained in the same manner as in Example 4, except that an aqueous solution of AATMAC was used instead of an aqueous solution of MTMAC.

Example 11
4 g of (2-(acryloyloxy)ethyl)trimethylammonium chloride (hereinafter referred to as ATMAC) as a second polymerizable monomer and 1 g of distilled water were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of ATMAC.

Plastic pieces were obtained in the same manner as in Example 4, except that an aqueous solution of ATMAC was used instead of an aqueous solution of MTMAC.

Example 12
4 g of N-(2-acryloyloxyethyl)-N-benzyl-N,N-dimethylammonium chloride (hereinafter referred to as ABDMAC) as a second polymerizable monomer and 1 g of distilled water were added to a bottle with a lid, and the mixture was stirred with a stirrer to obtain an aqueous solution of ABDMAC.

Plastic pieces were obtained in the same manner as in Example 4, except that an aqueous solution of ABDMAC was used instead of an aqueous solution of MTMAC.

<Comparative Example 2>
After mixing 14 g of BisMEPP and 6 g of NPG as the first polymerizable monomer, 0.04 g of (±)-camphorquinone, 0.1 g of ethyl p-dimethylaminobenzoate, 4 g of MTMAC as the second polymerizable monomer, and 6 g of NPG as the first polymerizable monomer were added, and the mixture was kneaded in an agate mortar until it became a uniform paste, and then irradiated with light from an LED with a wavelength of 365 to 465 nm and an irradiation intensity of 1200 mW/ ^cm for 5 minutes to polymerize and obtain plastic pieces.

Next, the appearance, antiviral properties, and durability of the antiviral properties of the plastic pieces (test specimens) were evaluated.

<Appearance of plastic pieces>
The appearance of the plastic piece obtained by photopolymerization, 15 mm in diameter and 1 mm in thickness, was evaluated by visually inspecting the surface for irregularities.

Figure 3 shows an optical microscope photograph at 100x magnification of the plastic piece of Example 4 before it hardens, and Figure 4 shows an optical microscope photograph at 100x magnification of the plastic piece of Comparative Example 2 before it hardens. Figure 5 shows the appearance of the plastic piece of Example 4 (after hardening), and Figure 6 shows the appearance of the plastic piece of Comparative Example 2 (after hardening).

The criteria for judging the appearance of plastic pieces are as follows:

Excellent: There are no irregularities on the surface of the plastic piece and the appearance of the plastic piece is good. Poor: There are irregularities on the surface of the plastic piece and the appearance of the plastic piece is poor.

<Antiviral>
In accordance with ISO 21702 Antiviral Properties (Non-Textile Products), the antiviral properties of the test specimens were evaluated using Porcine epidemic diarrhea virus, an enveloped virus, as the test virus.

The criteria for determining the antiviral properties of test strips are as follows:

Excellent: When the antiviral activity value of the test piece is 2 or more. Unacceptable: When the antiviral activity value of the test piece is less than 2.

<Sustained antiviral effect>
The test specimen was immersed in a neutral phosphate buffer solution for one month, and then the antiviral activity of the test specimen was evaluated in the same manner as above.

Table 2 shows the evaluation results for the appearance of the plastic pieces, their antiviral properties, and the durability of their antiviral properties.

Table 2 shows that the plastic pieces of Examples 4 to 12 have excellent appearance and high antibacterial properties and long-lasting antibacterial properties. For example, in Example 4, the pre-cured polymerizable composition 20 applied to the coating 10 is considered to have the second polymerizable monomer 40 uniformly dispersed in the first polymerizable monomer 30 (the precipitates of the second polymerizable monomer are fine) (Figure 1).

In contrast, the plastic piece of Comparative Example 2 was produced by curing a polymerizable composition obtained without using the first solvent, resulting in a poor appearance and poor durability of antibacterial properties. For example, in Comparative Example 2, the second polymerizable monomer 40 is not uniformly dispersed in the first polymerizable monomer 30 in the pre-cured polymerizable composition 20 applied to the coating 10 (the precipitate of the second polymerizable monomer is coarse) (Figure 2).

Although the above describes an embodiment of the present invention, the present invention is not limited to a specific embodiment, and various modifications and variations are possible within the scope of the invention described in the claims.

10 Coating 20 Polymerizable composition 30 First polymerizable monomer 40 Second polymerizable monomer

Claims (5)

1. A method for producing a polymerizable composition in which a solution of a second polymerizable monomer dissolved in a first solvent is dispersed in a first polymerizable monomer, the method comprising:
mixing the first polymerizable monomer, the second polymerizable monomer, and the first solvent;
the first polymerizable monomer is a liquid;
the second polymerizable monomer is a solid;
adding a surfactant when mixing the first polymerizable monomer, the second polymerizable monomer, and the first solvent;
the first polymerizable monomer is at least one selected from the group consisting of ethoxylated bisphenol A dimethacrylate and neopentyl glycol dimethacrylate;
the second polymerizable monomer is at least one selected from 2-(methacryloyloxy)ethyltrimethylammonium chloride, (3-acrylamidopropyl)trimethylammonium chloride, (2-(acryloyloxy)ethyl)trimethylammonium chloride, and N-(2-acryloyloxyethyl)-N-benzyl-N,N-dimethylammonium chloride;
The method for producing a polymerizable composition, wherein the first solvent is at least one selected from water, glycerin, and propylene glycol. The method for producing a polymerizable composition according to claim 1, wherein the second polymerizable monomer has a functional group that exhibits at least one of antibacterial and antiviral properties. The process comprises:
dissolving the second polymerizable monomer in the first solvent to obtain a solution;
mixing the solution with the first polymerizable monomer;
A method for producing the polymerizable composition according to claim 1 or 2, comprising: The method for producing a polymerizable composition according to claim 1 or 2, wherein the steps include: dissolving at least a portion of the first polymerizable monomer and the second polymerizable monomer in a second solvent to obtain a solution; distilling off the second solvent from the solution to obtain a dispersion in which the second polymerizable monomer is dispersed in at least a portion of the first polymerizable monomer; and mixing the dispersion with the first solvent. 1. A method for producing a polymerizable composition in which a solution of a second polymerizable monomer dissolved in a first solvent is dispersed in a first polymerizable monomer, the method comprising:
mixing the first polymerizable monomer, the second polymerizable monomer, and the first solvent;
the first polymerizable monomer is a liquid;
the second polymerizable monomer is a solid;
the steps include: dissolving at least a portion of the first polymerizable monomer and the second polymerizable monomer in a second solvent to obtain a solution; distilling off the second solvent from the solution to obtain a dispersion in which the second polymerizable monomer is dispersed in at least a portion of the first polymerizable monomer; and mixing the dispersion with the first solvent,
the first polymerizable monomer is at least one selected from the group consisting of ethoxylated bisphenol A dimethacrylate and neopentyl glycol dimethacrylate;
the second polymerizable monomer is at least one selected from 2-(methacryloyloxy)ethyltrimethylammonium chloride, (3-acrylamidopropyl)trimethylammonium chloride, (2-(acryloyloxy)ethyl)trimethylammonium chloride, and N-(2-acryloyloxyethyl)-N-benzyl-N,N-dimethylammonium chloride;
The method for producing a polymerizable composition, wherein the first solvent is at least one selected from water, glycerin, and propylene glycol .