JPS61289006A - Dental adhesive coating base composition - Google Patents

Abstract

PURPOSE:The titled composition, consisting of a copolymer obtained by copolymerizing a specific acrylic monomer in a specific proportion and a volatile solvent, capable of forming a uniform film having improved water resistance on the tooth surface and having improved adhesive strength to the dentine. CONSTITUTION:A dental adhesive coating base composition consisting of 5-40wt% copolymer expressed by formula I (R<1> and R<2> are 1-10C alkyl; R<3>-R<5> are H or CH3; X is 5-80wt%; Y is 10-95wt%; Z is 0-85wt%) and 60-95wt% volatile solvent, e.g. ethanol. the weight composition of the monomer in the acrylic copolymer is 5-80wt%, preferably 25-50wt% (meth)acrylic acid and 20-95wt%, preferably 50-75wt% alkyl (meth)acrylate, and polymerization reaction is carried out in the presence of a radical-forming catalyst in the above- mentioned volatile solvent at 50-100 deg.C. Since the composition contains no unreacted monomer, it retains high adhesive strength even in the saliva with good operability. The quality is stabilized without a fear for deterioration and solidification.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to a novel dental adhesive coating base composition that exhibits excellent adhesion to tooth structure.

BACKGROUND OF THE INVENTION Methyl methacrylate polymers, Bis-GMA polymers, and the like have been known as polymers used in dental compositions such as caries-preventing filling materials and adhesives. However, since these are used by polymerizing and curing in the mouth, such as room temperature polymerization with benzoyl peroxide and tertiary amines, or polymerization reaction using ultraviolet or visible light, there is a risk of infusion due to residual unreacted monomers. Moreover, in order to initiate polymerization, it is necessary to knead two types of pastes and irradiate light, resulting in poor operability. Furthermore, the monomer is unstable and tends to stick and solidify during long-term storage, making it difficult to guarantee product quality.

Summary of the Invention As a result of extensive research in view of the above-mentioned problems, the present inventors have discovered that a solution of a copolymer obtained by copolymerizing certain acrylic monomers in a specific ratio has the above-mentioned drawbacks. The present invention was completed based on the discovery that the present invention has excellent adhesion to the tooth surface.

That is, the present invention. Formula: [wherein R1 and R1 are each independently an alkyl group having 1 to 10 carbon atoms; R3, R4, and R5 are each independently a hydrogen or methyl group; X is 5 to 80% by weight; Y is 10 to
Provided is a dental adhesive coating base composition characterized in that a copolymer represented by 95% by weight and Z means 0 to 85% by weight is blended in an amount of 5 to 40% by weight based on the total weight. It is something.

According to the present invention, by applying purified acrylic copolymer represented by the above formula and dissolving it in a solvent to the tooth surface, a uniform coating with excellent water resistance is formed on the tooth surface. A composition was obtained that had strong adhesion to.

Detailed description of the invention Next, the present invention will be explained in detail.

Examples of monomers used in the production of the acrylic copolymer blended into the composition of the present invention include acrylic acid, methacrylic acid, and one or two of acrylic esters and methacrylic esters. These acrylic esters or methacrylic esters include methyl acrylate, methyl methacrylate, ethyl acrylate, ethyl methacrylate, butyl methacrylate, and acrylic acid.
2-ethylhexyl, 2-ethylhexyl methacrylate, etc. are preferably used.

The weight composition ratio of the monomers in the acrylic copolymer is 5 to 80% by weight of acrylic acid or methacrylic acid, preferably 25% by weight.
~50% by weight, containing one or two acrylic acid alkyl esters or methacrylic acid alkyl esters 2
0 to 95% by weight, preferably 50 to 75% by weight.

The weight average molecular weight of the acrylic copolymer used in the composition of the present invention is from several thousand to several hundred thousand.

The acrylic copolymer used in the composition of the present invention can be produced by conventional solution polymerization.

That is, each of the monomers is dispersed and dissolved in a volatile solvent at a predetermined ratio.

Such polymerization solvents include methanol, ethanol, isopropanol, acetone, chloroform, ethyl acetate, etc., but it is most preferable to use ethanol in consideration of intraoral administration.

As the polymerization catalyst used, known radical-forming compounds such as 2,2'-azobisisobutyronitrile, 2,2'-azobis(4-methoxy-2,4
-dimethylvaleronitrile), dimethyl 2,2'-azobisisobutyrate, 2,2'-azobis(2,4-dimethylvaleronitrile), benzoyl peroxide, diisopropyl purge carbonate, t-butyl perisobutyrate, etc. You can use it. The amount of these polymerization catalysts added is 0.05 to 2% by weight based on the total weight of monomers, preferably O
It is 11 to 0.5% by weight.

The heavy reaction is preferably carried out at 50 to 100°C, and it is generally preferable to carry out the reaction below the boiling point of the volatile solvent.

The obtained copolymer solution can normally be used satisfactorily as the composition of the present invention without purification.

The amount of the thus obtained copolymer represented by the above formula is 5 to 40% by weight, preferably 10 to 30% by weight, based on the total weight of the composition. If the blending amount exceeds 40%, the viscosity will be high and uniform coating will be difficult, making it unsuitable. On the other hand, if it is less than 5% by weight, sufficient adhesive strength cannot be obtained and a uniform film cannot be obtained.

The dental adhesive coating base composition containing the acrylic copolymer of the present invention is further blended with a viscosity modifier, etc., and is capable of adhering filling materials such as anti-caries cooling agents, orthodontic adhesives, and composite resins to teeth. It can also be applied to adhesives, dental lacquers containing pigments, therapeutic agents containing drugs, and the like.

Effects of the Invention Since the composition of the present invention does not contain unreacted monomers, it has no harmful effects, has good adhesion to teeth, and maintains high adhesive strength even in water or saliva. For example, when used as a caries preventive cold filler, a uniform film can be obtained by drying the tooth surface and applying it with a cotton ball. Compared to this, it has better operability. Furthermore, there is no fear of deterioration or solidification, and the quality is stable.

EXAMPLES The present invention will be explained in more detail below with reference to Examples and Usage Examples. All percentages herein mean percentages by weight.

Example 1 A 30% ethanol solution consisting of 25 g of methacrylic acid and 25 g of methyl methacrylate was prepared in a three-day flask equipped with a thermometer, reflux tube, and nitrogen introduction tube, and stirred for 1 to 2 hours under a nitrogen stream. I degassed it. Next, 0.5 g of 2.2'-azobisisobutyronitrile was added and polymerized at 70°C for 20 hours, and then 0.29 g of a polymerization initiation catalyst was added.
Polymerization was carried out at 78° C. for 4 hours to complete the reaction. A colorless and transparent 20% polymer solution was obtained by diluting with ethanol. The weight average molecular weight of the obtained copolymer was determined by gel permutation chromatography (GPC).
．． It was LX10'.

Example 2 In a three-day flask equipped with a thermometer, reflux tube, and nitrogen introduction tube, 15 g of methacrylic acid, 209 g of methyl methacrylate,
A 30% ethanol solution consisting of ethyl acrylate 159 was prepared and degassed by stirring for 1 to 2 hours under a nitrogen stream. Next, 0.259 of 2,2'-azobis(2,4-dimethylvaleronitrile) was added and polymerized at 60°C for 20 hours, and then 0.2g of polymerization initiation catalyst was added and heated at 78°C for 4 hours. Polymerization was carried out to complete the reaction. A colorless and transparent 20% polymer solution was obtained by diluting with ethanol. The weight average molecular weight of the obtained copolymer was 6.7x as measured by gel permutation chromatography (GPC).
It was l O'.

Example 3 In a three-day flask equipped with a thermometer, reflux tube, and nitrogen introduction tube, 15 g of methacrylic acid, 20 g of methyl methacrylate,
A 30% ethanol solution consisting of butyl methacrylate 159 was prepared and degassed by stirring for 1 to 2 hours under a nitrogen stream. Next, 70% t-butyl perisobutylene 1-0.2
After adding 5 g and polymerizing at 60°C for 20 hours, 0°2 g of a polymerization initiation catalyst was further added and polymerization was carried out at 78°C for 4 hours to complete the reaction. A colorless and transparent 20% polymer solution was obtained by diluting with ethanol. The weight average molecular weight of the obtained copolymer was determined to be 7.5 x 10' by gel permeation chromatography (CPC).

Test Example 1 The coating base composition of the present invention (ethanol solution) containing 20% of the copolymer obtained in Examples 1 to 3 is applied to a dry natural tooth after surface cleaning. After drying at room temperature for 10 minutes, the specimens were immersed in 20 ml of distilled water and stored at 37°C for 10 days, and their properties were visually judged. There was no change in the film on the surface of the dentition, and the results were good. obtained,
It was found to have sufficient water resistance.

Test Example 2 An impacted front tooth of a 2- to 3-year-old cow is embedded (φl x 2 cm) using instantly polymerized renon, with 1/2 of the crown incisal side exposed. A diameter of 3mm is placed between these so that the natural teeth touch each other.
A polyhynylidene chloride sheet with a hole in it is sandwiched, and the 20% ethanol solution obtained in Examples 1 to 3 is poured into the sheet, and the sheets are butt-bonded. After being stored in the air at room temperature for 24 hours, a tensile test was conducted using an autograph to measure the adhesive strength.

Results are shown as the average of 5 measurements.

Example Adhesive strength kg/cm”)1
17.8 2 7.3 3 6.5 These results show that the composition of the present invention has sufficient adhesive strength as a dental coating composition.

Claims (2)

[Claims] (1) Formula: ▲There are mathematical formulas, chemical formulas, tables, etc.▼ [In the formula, R^1 and R^2 each have a carbon number of 1 to 1]
an alkyl group having 0; R^3, R^4 and R^5 are each independently hydrogen or a methyl group; X is 5 to 80% by weight;
Y means 10 to 95% by weight; Z means 0 to 85% by weight] A dental adhesive coating base composition characterized in that a copolymer represented by the following is blended in an amount of 5 to 40% by weight based on the total weight. thing. (2) The composition according to item (1) above, which contains a volatile solvent in an amount of 60 to 95% by weight based on the total weight of the composition.