JP2022064455A - Thermoplastic resin composition for dentures - Google Patents

Abstract

To provide a thermoplastic resin for dentures, which has good adhesion to a backing material and a reline material, has high strength, and is excellent in machinability and polishability.SOLUTION: Provided is a thermoplastic resin for dentures in which 5 to 25 pts.mass of certain amorphous thermoplastic resin, such as polyvinyl chloride or polystyrene, to 100 pts.mass of polyester resin obtained by polycondensation of a diol component (A) containing the specific concentrations of spiroglycol (A1) having a cyclic acetal skeleton and ethylene glycol (A2) and a dicarboxylic acid component (B) containing the specific concentrations of a dicarboxylic acid compound (B1) having a polycyclic aromatic hydrocarbon skeleton and/or an ester thereof (B1') at a ratio of 1 mol:1 mol.SELECTED DRAWING: None

Description

The present invention relates to a denture thermoplastic resin composition suitable as a material for a denture base or a clasp of a non-metal clasp denture.

Partial dentures (removable partial dentures) are often used as prosthetic restorations for treatment when some teeth are missing due to caries or accidents. This removable partial denture is usually a denture part in which an artificial tooth that replaces the defective tooth is fixed to the denture base (partial denture) that covers the oral mucosa in the defect area, and an adjacent residual natural tooth so that it does not come off. It has a clasp (clasp), which is a maintenance device for attaching to dentures, but has a large connector for connecting a floor and a maintenance device at a remote position in the denture. It may have a small connector that connects the clasp to the removable partial denture or large connector.

As the clasp, a metal material is often used from the viewpoint of strength and durability, but a resin material may be used from the viewpoint of measures against metal allergies, aesthetics, and wearing comfort. Partial dentures whose clasps are made of thermoplastic resin material are also called non-metal clasp dentures (including cases where no metal material is used, as well as cases where some metal materials such as metal rests and metal frames are used). Due to the above-mentioned advantages, the demand is increasing.

In addition to heat-polymerized acrylic resins, injection-moldable polymethylmethacrylate (hereinafter abbreviated as PMMA) resins have been widely used in conventional dentures and partial dentures, but in recent years non-metal clasps have been used. Various thermoplastic resins such as polyamide-based, polyester-based, and polycarbonate-based resins that can be injection-molded for dentures are being sold by various manufacturers (Non-Patent Document 1).

Since the non-metal clasp denture constitutes a thin and thin part of the clasp, it is required to have toughness that does not shift or bend even when it is attached to the oral cavity and chews food, and flexibility that the clasp does not break even if it is dropped outside the oral cavity. .. Therefore, as these new thermoplastic resins, those having higher flexibility (lower bending elastic modulus) than heat-polymerized acrylic resins are generally used. On the other hand, the thermoplastic resin proposed as a material for artificial tooth beds and clasps has lower strength (for example, bending strength) than the heat-polymerized acrylic resin, and the surface is easily scratched and polishing is difficult. It has been pointed out (Non-Patent Document 1).

Regarding other physical properties of the above-mentioned thermoplastic resin, there is a certain tendency depending on the resin system, and it is selected according to the characteristics of each. For example, polyester-based resins have good adhesion to instantly polymerized resins used for denture base repair and relining, (meth) acrylate-based hard lining materials, silicone-based soft lining materials, and mucosal conditioning materials. Materials with low bending elasticity and high impact resistance have also been developed. However, even in the same resin system, each physical property value varies depending on the material, and the specific structure of the thermoplastic resin is often not clarified (Non-Patent Document 1).

Regarding the polyester resin used for optical molded products such as food packaging materials and plastic lenses, 3,9-bis (1,) is a polyester resin having excellent heat resistance, transparency, mechanical performance, and moldability. 1-Dimethyl-2-hydroxyethyl) 2,4,8,10-tetraoxaspiro [5.5] 5 mol% of spiroglycol having a specific structure such as undecane (hereinafter, may be referred to as "SPG"). 60 mol% or less (hereinafter, "x or more, y or less" may be simply referred to as "x to y"), and ethylene glycol is 30 mol% to 95 mol% (however, the mol% is spiro. A polyester resin obtained by polycondensing a diol component containing (based on the total amount of glycol and ethylene glycol) and a dicarboxylic acid component containing 80 mol% to 100 mol% of terephthalic acid and / or an ester thereof, and having an extreme viscosity. , Polyester resins having melt viscosity, molecular weight distribution, and glass transition temperature in predetermined ranges are known (Patent Document 1), but their suitability as a thermoplastic resin for artificial teeth is unknown.

Japanese Unexamined Patent Publication No. 2008-260964

Kenji Fueki et al. "Clinical application of removable partial denture (non-metal clasp denture) using thermoplastic resin" Journal of Japan Prosthodontic Society, Vol. 5, No. 4, pp. 387-408, 2013

In view of such circumstances, the present invention can form a denture base by injection molding, has high flexibility, and is an instantly polymerized resin, a (meth) acrylate-based hard lining material, a silicone-based soft lining material, and a mucous membrane. Provided is a thermoplastic resin material for dentures, which has the advantage of good adhesion to the adjusting material, has higher strength than the conventional polyester resin for denture bases, and has excellent machinability and greasability. It is an object of the present invention to provide a non-metal clasp denture having a clasp made of a molded body of a thermoplastic resin material for a denture.

As a result of studies to solve the above-mentioned problems, the present inventors have found that the polyester resin having a specific structure among the polyester resins disclosed in Patent Document 1 can solve the above-mentioned problems. The invention was completed.

That is, the first embodiment of the present invention is a thermoplastic resin composition for artificial teeth used as a material for artificial teeth, wherein the thermoplastic polyester resin: 100 parts by mass and the amorphous thermoplastic resin: 5 to 25 mass. Including the part
The thermoplastic polyester resin is a polyester resin obtained by polycondensing a diol component (A) and a dicarboxylic acid component (B) at a ratio of 1 mol: 1 mol.
The diol component (A) contains spiroglycol (A1) and ethylene glycol (A2) having a cyclic acetal skeleton.
The contents of the above (A1) and the above (A2) based on the total number of moles of all the diol compounds contained in the diol component (A) are (A1): 15 to 95 mol% and (A2), respectively. : 5 to 85 mol%, and the total content of the above (A1) and the above (A2) is 20 to 100 mol%.
The dicarboxylic acid component (B) contains a dicarboxylic acid compound (B1) having a polycyclic aromatic hydrocarbon skeleton and / or an ester thereof (B1').
The total content of the (B1) and the (B1') based on the total number of moles of all the dicarboxylic acid compounds contained in the dicarboxylic acid component (B) is 15 to 100 mol%.
The amorphous thermoplastic resin is at least one selected from the group consisting of polyvinyl chloride, polystyrene, polymethylmethacrylate, acrylonitrile-butadiene-styrene copolymer resin, polycarbonate, modified polyphenylene ether and glycol-modified polyethylene terephthalate. ,
It is a thermoplastic resin composition for dentures, which is characterized by the above.

The above-mentioned "diol component (A)" constituting the main component of the above-mentioned thermoplastic resin composition for dentures according to the first aspect of the present invention (hereinafter, also referred to as "the thermoplastic resin composition for dentures of the present invention"). A polyester resin obtained by polycondensing a dicarboxylic acid component (B) at a ratio of 1 mol: 1 mol "(hereinafter, also referred to as" specific polyester ") is a diol component (A) and a dicarboxylic which are raw materials thereof. Although it is defined as described above from the viewpoint of the acid component (B), it can also be expressed as follows from the viewpoint of the structure derived from each component. That is, "the number of structural units derived from spiroglycol (A1) having a cyclic acetal skeleton is 15 to 95% based on the total number of structural units derived from the diolinated component, and the structure is derived from ethylene glycol (A2). The number of units is 5% to 85%, the total number of both units is 20 to 100% or less, and the dicarboxylic acid having a polycyclic aromatic hydrocarbon skeleton is based on the total number of structural units derived from the dicarboxylic acid component. It can also be defined as "a polyester resin having a total number of structural units derived from the acid compound (B1) and its ester (B1') of 15 to 100%".

In the thermoplastic resin composition for artificial teeth of the present invention, it is preferable that the dicarboxylic acid compound (B1) having the polycyclic aromatic hydrocarbon skeleton is a naphthalene dicarboxylic acid in the specific polyester. Further, the amorphous thermoplastic resin is preferably an amorphous thermoplastic resin having a deflection temperature under load measured according to the method A (1.8 MPa) of ISO75 (JIS K7911) in the range of 60 to 150 ° C. ..

The second aspect of the present invention has a denture portion in which an artificial tooth is fixed to a partial bed and a clasp for mounting the denture portion on a hook tooth, and at least a part of the partial bed and the clasp are the present invention. It is a non-metal clasp denture characterized by being composed of a molded body of a thermoplastic resin composition for dentures.

The thermoplastic resin composition for dentures of the present invention can form a denture base by injection molding, has high flexibility and is an immediate polymerization resin, a (meth) acrylate-based hard lining material, a silicone-based soft lining material, and the like. It has the features of particularly good adhesion to the mucous membrane adjusting material, high strength, and excellent machinability and greasability.

The non-metal clasp denture using the thermoplastic resin composition for dentures of the present invention has excellent impact resistance due to its moderate flexibility, is less likely to break, and has high strength and a surface surface. It has high aesthetics of being smooth and glossy, and is also suitable for repairs and relining using instantly polymerized resins, (meth) acrylate-based hard lining materials, silicone-based soft lining materials, and mucosal conditioning materials. It has the feature.

As a result of studies to solve the above problems, the present inventors have found that among various existing polyester resins, the specific polyester is capable of forming a prosthesis base by injection molding, has high flexibility, and is various. We found that it not only has the characteristics of the conventional polyester resin for artificial dentition, which has good adhesion to the backing material, but also has the characteristics of high strength, excellent machinability and polishability, and is new. It has already been proposed as a polyester resin for artificial tooth beds (Japanese Patent Application No. 2019-108422).

The specific polyester is different from the polyester resin described in Patent Document 1 in that a benzene ring is introduced as a skeleton derived from a dicarboxylic acid in the form of a plurality of condensed rings instead of a single ring. As a result, the rigidity of the resin is increased, and the deflection temperature under load and the hardness of rockwell are also improved. As a result of these improvements in physical properties, machinability and wear resistance are improved, and the material is suitable as a denture base material in which transparency is unlikely to decrease due to cutting. That is, the heat applied to the denture base during dry-type cutting rises to about 50 ° C at the lowest, and rises to about 70 ° C to 80 ° C when the same place is cut for a long time. For this reason, when the deflection temperature under load is low, the resin softens and welds to the cutting bar and artificial tooth base, reducing machinability, and the resin softened by heat generation remains on the surface even during polishing, resulting in reduced gloss. do. Further, when the Rockwell hardness is low, the load from the cutting bar tends to cause excessive cutting and deformation due to the bending of the resin, and further, polishing scratches due to polishing sand are likely to occur on the surface. On the other hand, the specific polyester has improved machinability and polishability due to the improved rigidity of these resins.

The present invention further studies a denture using a specific polyester having such excellent features as a denture base material, and as a result, a specific amorphous thermoplastic resin (Amorphous Thermoplastic Resin) is blended within a certain range. By doing so, it was found that the adhesiveness with the backing material at the time of the backing treatment is further improved. That is, the adhesive strength with the backing material for the artificial tooth bed made of a specific polyester was about 5 to 6 MPa, whereas the adhesive strength with the backing material was about 5 to 6 MPa, whereas polyvinyl chloride (PVC), polystyrene (PS), polymethylmethacrylate (PMMA), and acrylic nitrile butadiene. At least one amorphous thermoplastic resin selected from the group consisting of styrene copolymer resin (ABS), polycarbonate (PC), modified polyphenylene ether (m-PPE) and glycol-modified polyethylene terephthalate (PET-G). Hereinafter, when a resin composition containing 5 to 25 parts by mass of (hereinafter, also simply referred to as “specific amorphous resin”) with respect to 100 parts by mass of the specific polyester is used as the artificial toothbed material, the amount is improved to 10 MPa or more. The reason why such an effect is obtained is that the primer used in the lining treatment is imparted with solubility or swelling property to ethyl acetate generally contained as a solvent, and the roughening by the primer treatment results in the roughening. This is probably due to the increased adhesiveness with the backing material.

Hereinafter, the specific polyester and the specific amorphous resin, which are the main components of the thermoplastic resin for artificial teeth of the present invention, will be described, and then the thermoplastic resin for artificial teeth of the present invention will be described in detail.

1. 1. Specified Polyester Specified polyester is a polyester resin suitably used as a material for artificial tooth beds, and is obtained by polycondensing a diol component and a dicarboxylic acid component at a ratio of 1 mol: 1 mol in the same manner as a conventional polyester resin. Is something that can be done. And, as both of these components, it is characterized in that those having a specific composition are used. That is, the diol component contains spiroglycol (A1) and ethylene glycol (A2) having a cyclic acetal skeleton, and the above (A1) is based on the total number of moles of all the diol compounds contained in the diol component (A). And the content of the above (A2) is (A1): 15 to 95 mol% and (A2): 5 to 85 mol%, respectively, and the total content of the above (A1) and the above (A2) is 20 to. Must be 100 mol%. Further, the dicarboxylic acid component contains a dicarboxylic acid compound (B1) having a polycyclic aromatic hydrocarbon skeleton and / or an ester thereof (B1'), and is the total of all the dicarboxylic acid compounds contained in the dicarboxylic acid component (B). The total content of the above (B1) and the above (B1') based on the number of moles needs to be 15 to 100 mol%.

In other words, the specific polyester is a polyester resin obtained by polycondensing a diol compound and a dicarboxylic acid compound at a ratio of 1: 1 and comprises the total number of structural units derived from the diol compound in the polyester resin. As a reference, the number of structural units derived from spiroglycol (A1) having a cyclic acetal skeleton is 15 to 95%, the number of structural units derived from ethylene glycol (A2) is 5 to 85%, and the number of both units is The total number of structural units derived from the dicarboxylic acid compound (B1) having a polycyclic aromatic hydrocarbon skeleton is based on the total number of structural units derived from the dicarboxylic acid compound in the polyester resin. It is characterized by being made of a polyester resin which is 15 to 100%.

1-1. Glycol component (A)
The specific polyester contains a spiroglycol (A1) having a cyclic acetal skeleton in the diol component (A), and thus has the characteristics of having heat resistance, transparency, moldability, and mechanical performance of the resin. The content of the spiroglycol (A1) having a cyclic acetal skeleton in the diol component (A) may be 15 mol% to 95 mol%, but is 30 to 80 mol%, particularly 40 to 65 mol%. Is preferable.

The content of ethylene glycol (A2) may be 5 to 85 mol% or less, but is preferably 10 to 70 mol%, particularly preferably 15 to 55 mol%. At this time, the lower limit of the total content of (A1) and (A2) is 20 mol% or more, preferably 40 mol% or more, particularly 55 mol% or more, and the upper limit is always 100 mol% or less.

Spiroglycol (A1) having a cyclic acetal skeleton is a compound having a structural formula represented by Chemical formula 1 {bis (hydroxypivalaldehyde) pentaerythritol acetal cyclic acetal: CAS No. It means 1455-42-1}.

Further, the diol component (A) is preferably composed of only the (A1) and (A2), but is a diol compound other than the spiroglycol (A1) and the ethylene glycol (A2) having the cyclic acetal skeleton (hereinafter, (Also referred to as “other diol compound”) can be contained as a residual component when the total content of both is less than 100 mol%, depending on the content of these components. Further, although it depends on the type of the other diol compound, when a specific "other diol compound" such as cyclohexanedimethanol is used, the content of the compound is made higher than the content of the above (A2). In some cases, the effect is higher. In such cases, the content of the "other diol compound" is preferably 35 to 60 mol%, particularly 40 to 50 mol%. However, from the viewpoint of the effect, the content of the above (A1) tends to be preferably 40 to 65 mol%. Therefore, when the above-mentioned "other diol compound" is contained, the content of the above (A1) is contained. It is preferable to replace a part of the above (A2) with the content while keeping the ratio within this range.

Examples of the "other diol compounds" that can be used include trimethylene glycol, 2-methylpropanediol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, and 1,6-hexanediol. Aliphatic diols such as diethylene glycol, triethylene glycol, propylene glycol and neopentyl glycol; polyether compounds such as polyethylene glycol, polypropylene glycol and polybutylene glycol; 1,3-cyclohexanedimethanol, 1,4-cyclohexanedimethanol , 1,2-Decahydronaphthalenedic methanol, 1,3-Decahydronaphthalenedic methanol, 1,4-Decahydronaphthalenedic methanol, 1,5-Decahydronaphthalenedic methanol, 1,6-Decahydronaphthalenedic methanol , 2,7-Decahydronaphthalenedimethanol, tetralindimethanol, norbornandimethanol, tricyclodecanedimethanol, 5-methylol-5-ethyl-2- (1,1-dimethyl-2-hydroxyethyl) -1, Alicyclic diols such as 3-dioxane and pentacyclododecane dimethanol; 4,4'-(1-methylethylidene) bisphenol, methylene bisphenol (bisphenol F), 4,4'-cyclohexylidene bisphenol (bisphenol Z) , 4,4'-sulfonyl bisphenol (bisphenol S) and other bisphenol alkylene oxide adducts; hydroquinone, resorcin, 4,4'-dihydroxybiphenyl, 4,4'-dihydroxydiphenyl ether, 4,4'-dihydroxydiphenylbenzophenone Examples thereof include alkylene oxide adducts of aromatic dihydroxy compounds such as. Among these, at least one selected from the group consisting of 1,3-propanediol, 1,4-butanediol, neopentyl glycol and 1,4-cyclohexanedimethanol should be used because of the improvement in processability. Is preferable.

1-2. Dicarboxylic acid component (B)
The dicarboxylic acid component (B) contains a dicarboxylic acid (B1) having a polycyclic aromatic hydrocarbon skeleton and / or an ester thereof (B1'). Moreover, the total content of the (B1) and the (B1') based on the total number of moles of all the dicarboxylic acid compounds contained in the dicarboxylic acid component (B) needs to be 15 to 100 mol%. As a result, the rigidity of the resin is improved, and good machinability and polishability can be obtained. The lower limit of the total content of the above (B1) and the ester (B1') in the dicarboxylic acid component (B) is preferably 25 mol% or more, particularly preferably 50 mol% or more.

Here, the dicarboxylic acid (B1) having a polycyclic aromatic hydrocarbon skeleton is a polycyclic aromatic acid such as naphthalene, anthracene, naphthalene, pentacene, benzopyrene, chrysene, pyrene, triphenylene, corannulene, coronene, and ovalene in the molecule. Examples thereof include dicarboxylic acids having a hydrocarbon skeleton and esterified products thereof. Among these, it is preferable to use naphthalene dicarboxylic acid from the viewpoint of biosafety.

The substitution position of the dicarboxylic acid of the naphthalenedicarboxylic acid is not particularly limited, but it is preferably a naphthalenedicarboxylic acid in which the carboxylic acid is substituted one by one in different aromatic rings, and 2,6-naphthalenedicarboxylic acid is preferable. Especially preferable.

Further, the ester (B1') of the dicarboxylic acid (B1) having the polycyclic aromatic hydrocarbon skeleton is a compound capable of forming a polyester resin by transesterification reaction with the diol component, and is removed at that time. It means an ester of the alcohol compound to be separated and the above (B1). As the alcohol compound, a monohydric alcohol having 1 to 6 carbon atoms is usually used. As (B1), an ester of naphthalenedicarboxylic acid is preferable for the same reason as described above, and examples of the ester include dimethyl naphthalenedicarboxylate, dipropyl naphthalenedicarboxylic acid, diisopropyl naphthalenedicarboxylate, dibutyl naphthalenedicarboxylate, and naphthalenedicarboxylic acid. Dicyclohexyl and the like can be mentioned.

The dicarboxylic acid component (B) may also contain a dicarboxylic acid compound other than the above (B1) and / or an ester thereof (hereinafter, also referred to as “other dicarboxylic acid compound or the like”). "Other dicarboxylic acid compounds, etc." include aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, 2-methylterephthalic acid, biphenyldicarboxylic acid, and tetralindicarboxylic acid; , Sveric acid, azelaic acid, sebacic acid, dodecanedicarboxylic acid and other aliphatic dicarboxylic acids; cyclohexanedicarboxylic acid, decalindicarboxylic acid, norbornandicarboxylic acid, tricyclodecanedicarboxylic acid, pentacyclododecanedicarboxylic acid and other alicyclic dicarboxylic acids. ; And their esterified products can be exemplified. Among them, it is preferable to use aromatic dicarboxylic acids such as terephthalic acid, isophthalic acid, phthalic acid, 2-methylterephthalic acid, biphenyldicarboxylic acid and tetralindicarboxylic acid and their esterified products, and further, isophthalic acid, terephthalic acid and them. It is more preferable to use the esterified product of.

1-3. Polycondensation method The method of polycondensing the diol component (A) and the dicarboxylic acid component (B) at a ratio of 1 mol: 1 mol is a transesterification method known as a conventional method for producing a polyester resin, directly. A melt polymerization method such as an esterification method, a solution polymerization method, or the like can be adopted without particular limitation. For example, it is disclosed in Patent Document 1 as a method for producing the "polyester resin obtained by polycondensing a specific diol component including SPG or the like and a specific dicarboxylic acid component" described in Patent Document 1. By applying the above method to the raw material system of the present invention, it can be suitably carried out.

In addition, in Patent Document 1, regarding the said manufacturing method, "for example, a melt polymerization method such as a transesterification method, a direct esterification method, or a solution polymerization method can be mentioned. Also, various stabilizers such as polymerization catalysts, heat stabilizers and photostabilizers, polymerization modifiers and the like used for polymerization can be conventionally known. As the transesterification catalyst, manganese, cobalt, zinc, titanium, calcium and the like can be used. Examples of the compound of the above, compounds such as manganese, cobalt, zinc, titanium and calcium as the esterification catalyst, and amine compounds as the anti-etherification agent. Examples of the polycondensation catalyst include germanium, antimony, tin and titanium. Examples thereof include various phosphorus compounds such as phosphoric acid, phosphite, and phenylphosphonic acid as heat stabilizers. Other light stabilizers, antistatic agents, lubricants, antioxidants, and transesterification agents are also effective. A mold or the like may be added. The timing of addition of SPG is not particularly limited, and it may be added after the completion of the esterification reaction or the transesterification reaction. At that time, in the direct esterification method, in order to improve the slurry property. Water may be added. "

The polyester resin (specific polyester) thus produced is pelletized or powdered by a conventional method and used. For example, when pelletizing, it is molded into strands of a certain thickness by a device such as a kneader or an extruder, and cut into small pieces to a certain length using a cutter, pelletizer, crusher, etc. , Pellet-like.

1-4. Method for confirming specific polyester Some of the polyester resins obtained by the above method are in a pelletized or powdered state as a resin material (although it is not known that the resin material can be used as a material for artificial dentition). There are some that can be obtained at, so you can use it as a specific polyester. Whether or not the polyester resin corresponds to a specific polyester is determined by performing ¹ H-NMR measurement on a solution dissolved in deuterated chloroform, assigning peaks, and then calculating the content ratio of each component from the integrated value of the peaks. It can also be confirmed by doing so.

The attribution of peaks derived from each component is shown below for reference.

-Derived from ethylene glycol (δ = 4.7044H)
-Derived from spiroglycol (δ = 4.52 2H, δ = 4.32 2H, δ = 4.19 4H, δ = 3.54 4H, δ = 3.32 2H, δ = 1.04 12H)
-Derived from cyclohexanedimethanol {δ = 4.29 (cis), 4.19 (trans) 4H, δ = 2.05 (cis), 1.80 (trans) 2H, δ = 1.94 (trans), 1 .14 (cis) 4H, δ = 1.66 (cis), 1.56 (trans) 4H}
-Derived from terephthalic acid (δ = 8.144H)
-Derived from naphthalene dicarboxylic acid (δ = 8.62 2H, δ = 8.12 2H, δ = 8.03 2H).

Further, in a thermoplastic resin, the physical property values often change depending on the dispersion state of the copolymerization unit in the molecule and the molecular weight distribution, but it is difficult to analyze these and specify the structure of the thermoplastic resin in detail. Therefore, it is also practiced to specify the resin according to the range of physical property values and the like.

Among the polyester resins obtained by the above-mentioned method, the specific polyester conforms to the B method of JIS standard K7911-2: 2007 (ISO75-2: 2004) because of the high effect as described above. The deflection temperature under load measured in the above is 85 ° C or higher and 125 ° C or lower, and the Rockwell hardness measured in accordance with the JIS standard K7202-2: 2001 (ISO2039-2: 1987) L scale is 90 or higher and 120 or lower. It is preferably a certain polyester resin.

2. 2. Specific Amorphous Resin Next, an amorphous thermoplastic resin (specific amorphous resin) used for the thermoplastic resin for artificial teeth of the present invention will be described.

2-1. Amorphous thermoplastic resin Amorphous thermoplastic resin is a thermoplastic resin that does not have crystal portions that are regularly arranged in the molecular structure when it is solidified and has a random structure that is irregularly entangled. means. Examples of the amorphous thermoplastic resin include polyvinyl chloride (PVC), polyvinyl alcohol (PVA), polystyrene (PS), polymethylmethacrylate (PMMA), acryliconitrile-butadiene-styrene copolymer resin (ABS), and polycarbonate (PC). , Modified polyphenylene ether (m-PPE), polyethersulfone (PES or PSU), polyetherimide (PEI), polyamideimide (PAI), polysulfone (PSF or PSU) and the like are generally known. In addition, glycol-modified polyethylene terephthalate (PET-G) improved by adding cyclohexanedimethanol to polyethylene naphthalate (PET), which is usually known as crystalline, and poly using bisphenol A as a diol component instead of ethylene glycol. Arylate (PAR) and the like are also amorphous resins. The cycloolefin polymer (COP) is also an amorphous resin.

2-2. Specified non-crystalline resin In the thermoplastic resin composition for artificial teeth of the present invention, the specific amorphous resin includes polyvinyl chloride (PVC), polystyrene (PS), polymethylmethacrylate (PMMA), and acrylonitrile-butadiene-styrene copolymerization. At least one selected from the group consisting of resin (ABS), polycarbonate (PC), modified polyphenylene ether (m-PPE) and glycol-modified polyethylene terephthalate (PET-G) is used.

These specific amorphous resins are often soluble or swellable with ethyl acetate contained as a solvent in primers, adhesives, etc., which are pretreatment agents for lining treatment, and therefore are therefore specific amorphous. It is considered that the inclusion of the resin improved the adhesiveness with the backing material. For this reason, it is preferable to use a specific amorphous resin having solubility or swelling property in ethyl acetate. Here, "having solubility or swelling property with respect to ethyl acetate" means that when a molded product of an amorphous thermoplastic resin is immersed in an excessive amount of ethyl acetate and left at 37 ° C., the molded product is swelled or dissolved. It means that the shape changes. Whether or not it has solubility or swelling property in ethyl acetate can be confirmed, for example, as follows. That is, one amorphous thermoplastic resin pellet having a pellet diameter and / or a pellet length of about 3 to 5 mm can be visually observed and confirmed after being immersed in 1 ml of ethyl acetate at 37 ° C. for 24 hours. Generally, when a resin molded product is immersed in a solvent and left to stand, no change occurs if the resin does not have swellability and solubility in the solvent. In addition, when it is dissolved in a solvent, it generally goes through the process of cloudiness of the resin molded product → swelling of the resin molded product (apparent volume increase) → shape collapse of the resin molded product → dissolution. Observed to be soluble or swellable if the volume is clearly increased by swelling, shape collapse is seen by dissolution, or it is completely dissolved. Judging, if there is no change, or if the pellet is simply cloudy, it is judged that it has no solubility or swelling property.

From the viewpoint of compatibility with the specific polyester or blendability, the specific amorphous resin has a deflection temperature under load measured according to the method A (1.8 MPa) of ISO75 (JIS K7191) in the range of 60 to 150 ° C. Is preferable. When the deflection temperature under load of the specific amorphous resin is within this range, it can be easily made uniform during blending (during melt kneading).

3. 3. The thermoplastic resin composition for artificial teeth of the present invention The thermoplastic resin composition for artificial teeth of the present invention is a thermoplastic resin composition exclusively used as an artificial tooth member such as an artificial tooth bed and a clasp, and is a specific polyester: 100 parts by mass. It contains 5 to 25 parts by mass of the specific amorphous resin. By having such a composition, the adhesiveness to the backing material can be made higher without impairing the characteristics of the specific polyester. The amount of the specific amorphous resin to be blended is preferably 5 to 20 parts by mass because it is necessary to develop adhesiveness while not impairing the original physical properties of the specific polyester as much as possible. It is particularly preferably 15 parts by mass.

The thermoplastic resin component contained in the thermoplastic resin composition for artificial teeth of the present invention is preferably composed of only a specific polyester and a specific amorphous resin, but other thermoplastics as long as it does not inhibit the curing of the present invention. It can also contain resin. In addition, as components other than resin, coloring materials such as pigments and dyes, fillers such as inorganic fillers and organic fillers, mold release agents, ultraviolet absorbers, light stabilizers, antioxidants, lubricants, flame retardants, and charges. An inhibitor or the like may be appropriately added.

The thermoplastic resin composition for artificial teeth of the present invention is a mixture of a specific polyester powder or pellet, a specific amorphous resin powder or pellet, and various additives (usually powders) such as pigments to be blended as needed. Although these may be melt-kneaded, it is preferable to use them in the form of powder or pellets. For melt kneading, it is common to use a device such as a heated twin-screw extrusion kneader. For example, the mixture prepared in advance may be put into a feeder of a twin-screw extruder, for example, the barrel temperature may be set to 270 ° C. to 280 ° C., and the mixture may be kneaded at a screw rotation speed of 50 to 150 rpm. The screw configuration is an appropriate configuration by combining a feed screw that feeds resin and a kneading disk that is kneaded by applying shear force. The resin kneaded in this way is pelletized or powdered by a conventional method and used. For example, when pelletizing, it is molded into strands of a certain thickness by a device such as a kneader or an extruder, and cut into small pieces to a certain length using a cutter, pelletizer, crusher, etc. , Pellet-like.

The thermoplastic resin for dentures of the present invention can be molded into a denture base by injection molding and has high flexibility and immediate polymerization resin, (meth) acrylate-based hard lining material, silicone-based soft lining material, and mucosal preparation. Not only does it have the characteristics of conventional polyester resin for denture bases, which has good adhesion to the material, but it also has the characteristics of high strength and excellent machinability and polishability. Therefore, the denture bed of the present invention having a denture base manufactured by using the denture thermoplastic resin of the present invention, and the non-metal of the present invention in which the denture base and the clasp portion are formed of the denture thermoplastic resin of the present invention. The clasp denture has excellent impact resistance due to its moderate flexibility, is less likely to break, and has high aesthetics such as high strength, smooth surface and gloss, and is an instantly polymerized resin. Meta) It has the feature that it is suitable for repair and relining using acrylate-based hard lining material, silicone-based soft lining material, and mucous membrane adjusting material.

4. Non-metal clasp denture of the present invention and its manufacturing method The non-metal clasp denture is a kind of partial denture (local denture) belonging to the category of denture having a denture base, and covers the oral mucosa in the defect region. A clasp (clasp: hook) that is a maintenance device for attaching to a denture consisting of an artificial tooth that replaces a missing tooth on a (partial floor) and a denture consisting of adjacent residual natural teeth so that it does not come off. ). In the non-metal clasp denture, the clasp is made of a non-metal material such as a thermoplastic resin material. However, the use of a metal material is not completely denied, and a member made of a metal material such as a metal rest or a metal frame may be included in a part other than the clasp.

The non-metal clasp denture of the present invention has a denture portion in which an artificial tooth is fixed to a partial floor and a clasp for mounting the denture portion on a hook tooth, and at least a part of the partial floor and the clasp are the present invention. It is characterized by comprising a molded body of a thermoplastic resin composition for dentures.

In the non-metal clasp denture of the present invention, the clasp and / or at least a part of the denture base may be made of the present thermoplastic resin material, but the clasp and the resin denture base are all made of the present thermoplastic resin material. Further, it is preferable that both are integrally formed.

The non-metal clasp denture of the present invention is suitably manufactured by a manufacturing method including an injection molding step of forming at least a part of the clasp and / or the denture base by injection molding the thermoplastic resin material. Can be done.

The above injection molding process is not particularly different from the method for manufacturing a non-metal clasp denture by a conventional injection molding method using a thermoplastic resin, except that this thermoplastic resin material is used as a raw material resin for injection molding, for example. A plaster mold created based on the impression of the oral cavity collected from the patient is used as a molding mold, the molding mold is set in an injection molding machine, and the heated and softened thermoplastic resin material is injected into the molding machine. , A method of removing from the mold after cooling can be adopted. When a molding die having no clasp portion is used, the denture with a floor of the present invention having no clasp portion can be manufactured, and when a molding having a clasp portion is used. The non-metal clasp denture of the present invention can be manufactured.

Hereinafter, the above method will be specifically described. That is, in the above method, in order to create a molding mold, first, plaster is poured into the impression of the shape of the patient's oral cavity collected using a silicone-based impression material, an alginate-based impression material, or an agar impression material, and then the gypsum is poured into the patient's oral cavity. Make a plaster model that imitates the shape of. Next, after designing the foundation floor on the obtained gypsum model, a curable composition called a room temperature polymerized resin was pressure-welded to the design line on the model and placed on the gypsum model (if necessary). Make a foundation floor (with a clasp). After that, dental paraffin wax is placed on the foundation floor like a bank to create a part called a wax embankment for arranging artificial teeth, and the foundation floor on which the wax embankment is formed is removed from the masonry model and occlused. The floor. This occlusal bed is placed in the patient's oral cavity, occlusal is obtained, and the occlusal bed is adjusted. The adjusted occlusal bed is set on the plaster model again and attached to the articulator to reproduce the jaw movement and occlusal state in the oral cavity. Create an arrangement). The negative mold of the obtained wax denture becomes a molding mold for injection molding.

The molding die is usually produced through a three-step burying operation as described below. That is, first, the gypsum model and the wax denture set in the gypsum model are placed under the flask of the dental injection molding machine, and then only the gypsum model is buried and the wax denture is kneaded so as to come out above the flask. Perform primary burial by pouring the gypsum and hardening it. Next, the mixed plaster is placed so as to cover the wax denture, and the secondary burial is performed. After that, the upper part of the flask is fitted to the lower part of the flask and the lid is put on, and the mixed gypsum is poured from the hole made in the upper part of the flask to perform tertiary burial. Then, after the gypsum of the tertiary burial is hardened, the upper part and the lower part of the flask are once divided, and the foundation floor and the wax embankment are removed. If the wax embankment is difficult to remove, pour hot water to dissolve it. Then, only the artificial tooth is buried in the plaster. The upper part of the flask is fitted to the lower part of the flask again, and the molded product is sealed.

Injection molding is performed by supplying pellets of the present thermoplastic resin material from which water has been removed by vacuum drying in advance to an injection molding machine in which the molding die is set. Specifically, the required amount of the thermoplastic resin material is supplied, and the pellet is melted by applying heat in the resin melting part of the injection molding machine in the range of about 150 ° C. to 400 ° C. for about 5 to 60 minutes. After that, an air pressure of 0.1 to 2.0 MPa is applied to the injection molder with an air compressor to inject the molten resin, and the set flask (molding mold) is filled with the resin. After the resin has cooled and hardened, the flask is divided and the plaster is divided using a mallet or the like, and the denture (main denture) in which the resin and the artificial tooth are integrated is taken out.

Since burrs are attached to the entire circumference of the removed denture, cut while protecting the floor edge with a stamp bar or a resin point. The surface cut using the points is polished from medium to fine among the rough, medium, and fine types using a sandpaper cone, and then polished using a raise. For polishing with a laze, first use the felt cone with sand and then the bristle brush with sand, smooth the surface, wash well with water, and then transfer to finish polishing. Use zinc oxide on the vellus hair brush and abrasive on the cloth buff in that order to polish the surface. Raise is used at low speed to prevent the polished surface from drying and generating heat. Then, by adapting it to the oral cavity and making final adjustments, it is possible to obtain a finished denture with a floor of the present invention and a non-metal clasp denture of the present invention.

In order to specifically explain the present invention, examples and comparative examples will be given, but the present invention is not limited thereto.

1. 1. Reference Examples 1 to 4 and Reference Comparative Examples 1 to 7
First, it will be described with reference to Reference Examples and Reference Comparative Examples that the specific polyester which is the main component of the thermoplastic resin composition of the present invention is excellent as a polyester resin for a denture base.

After analyzing the commercially available thermoplastic resins A to K shown below and determining whether or not they correspond to specific polyesters, the deflection temperature under load, rockwell hardness, machinability and greasability are determined for each thermoplastic resin. It was measured and evaluated. The details are shown below.

1-1. Thermoplastic resin ・ A: Artesta S1000 (manufactured by Mitsubishi Gas Chemical Company, Inc.)
・ B: Artesta S2000 (manufactured by Mitsubishi Gas Chemical Company, Inc.)
・ C: Artesta S3000 (manufactured by Mitsubishi Gas Chemical Company, Inc.)
・ D: Artesta S4500 (manufactured by Mitsubishi Gas Chemical Company, Inc.)
・ E: Artesta SN1500 (manufactured by Mitsubishi Gas Chemical Company, Inc.)
・ F: Artesta SN3000 (manufactured by Mitsubishi Gas Chemical Company, Inc.)
・ G: Artesta SN4500 (manufactured by Mitsubishi Gas Chemical Company, Inc.)
・ H: Artesta SH (manufactured by Mitsubishi Gas Chemical Company, Inc.)
・ I: Acrylic shot (manufactured by Yamahachi Dental Industry Co., Ltd .: PMMA resin for denture base)
・ J: Esteshot (manufactured by Eyecast Co., Ltd .: PET resin for denture base)
・ K: Esteshot Bright (made by Eyecast Co., Ltd .: polyester resin for denture base)

1-2. Judgment as to whether or not it corresponds to the specific polyester (1) About the thermoplastic resin I The thermoplastic resin I is an acrylic resin commercially available for the denture base and does not correspond to the specific polyester.

(2) Thermoplastic Resins (Polyester Resins) A to H, J and K Various Artesta Resins of Thermoplastic Resins A to H are polyester resins sold by Mitsubishi Gas Chemicals Co., Ltd., and are sheet films for displays. , Food containers, sealant films, beverage containers, cosmetic containers, pharmaceutical containers, seasoning bottles, miscellaneous goods / stationery, protective covers, etc. The thermoplastic resins J and K are polyester resins commercially available for denture bases.

These thermoplastic resins (polyester resins) A to H, J and K were analyzed as follows, and it was determined whether or not they corresponded to the specific polyester resin. That is, one pellet of each resin was immersed in 1 ml of deuterated chloroform (including tetramethylsilane as an internal standard), left at 37 ° C. for 6 hours to completely dissolve, and the solution was transferred to ^an NMR tube. H-NMR measurement was performed. The measurement was performed with JEM-ECA 400II type manufactured by JEOL RESONANCE, 16 times of integration, at 400 MHz. After assigning peaks to the obtained NMR chart, those for which no peaks assigned to SPG were confirmed were judged to be non-specific polyester resins that do not correspond to specific polyesters, and spiroglycol (SPG). For those with confirmed peaks attributed to, terephthalic acid (TPA), 2,6-naphthalenedicarboxylic acid (NDCA), ethylene glycol (EG), spiroglycol (SPG), 1,4-cyclohexanedimethanol ( The content ratio of each component was calculated from the integrated value of the peaks attributed to CHDM). The analysis results are shown in Table 1.

From Table 1, the thermoplastic resins (polyester resins) A to D, J and K (for J and K, no peak derived from naphthalene dicarboxylic acid was also confirmed) are non-specific polyester resins that do not correspond to the specific polyester. It can be seen that the thermoplastic resins (polyester resins) E to H correspond to the specific polyester.

1-3. Various Physical Properties Measurement Methods and Evaluation Criteria for Thermoplastic Resins A to K (1) Deflection Temperature (HDT) Measurement Using a heating press (IMC-11D2-C, manufactured by Imoto Seisakusho Co., Ltd.) and a mold made by SUS, air bubbles. A smooth test piece of 10 mm × 80 mm × 4 mm was prepared. The deflection temperature under load (° C.) was measured in accordance with JIS standard K7191-2: 2007 (ISO75-2: 2004). The conditions were the B method in which a load of 0.45 MPa was applied, and the flatwise method was used. The HDT test device S6-MH manufactured by Toyo Seiki Seisakusho Co., Ltd. was used for the measurement.

(2) Rockwell hardness (HRL) measurement Using a heating press machine (IMC-11D2-C manufactured by Imoto Seisakusho Co., Ltd.) and a mold made of SUS, a smooth test piece of 20 mm square and 6 mm thick without bubbles is formed. The Rockwell hardness (HRL) was measured on an L scale with a test load of 588.4 N and a steel ball indenter diameter of 6.35 mm in accordance with JIS standard K7202-2: 2001 (ISO2039-2: 1987). .. In addition, AR-10 of Akashi Co., Ltd. was used for the measurement, and each test piece was measured 3 times using 3 test pieces per sample, and the average value of all 9 times was defined as Rockwell hardness (HRL). ..

(3) Flexural strength measurement Using a heating press (IMC-11D2-C manufactured by Imoto Seisakusho Co., Ltd.) and a mold made of SUS, the resin was molded into a plate shape having a thickness of 15 mm × 30 mm and a thickness of 2 mm. The molded body was cut out by 2 mm using a precision cutting machine (Isomet LS manufactured by Buehler Co., Ltd.) to prepare a test piece of 2 mm × 2 mm × 30 mm. The dimensions were measured and immersed in ion-exchanged water at 37 ° C. for 1 week and used for the bending test. The bending test was performed under the conditions that the test piece was set on a precision universal testing machine (manufactured by Shimadzu Corporation, AG-Xplus 50 kN), the distance between the fulcrums was 20 mm, and the crosshead speed was 1 mm / min. Measurements were made for 5 test pieces in one sample, and the average value was taken as the bending strength (MPa).

(4) Evaluation of machinability Various resins are vacuum-dried and molded into blocks of 10 mm x 10 mm x 12 mm using an injection molding machine for dental technicians (Pro Jet II, manufactured by Yamahachi Dental Industry Co., Ltd.). I got a body. A pin for cutting is adhered to this molded body, attached to a dry cutting machine (RolandDG Co., Ltd., DWX-50), and a cutting bar (Yamachi Dental Industry Co., Ltd., CAD / CAM milling bar diamond coat) is attached. The type φ2 mm, φ0.8 mm) was cut into a crown shape, and the state during cutting and the size of the cutting residue were observed and evaluated. The reason why the dry-type cutting machine is used is that the dental technician usually cuts and polishes the denture base by the dry-type.

The evaluation criteria for machinability are shown below.
◎: There is no problem in cutting. The cutting debris is fine and the cutting debris does not cling to the cutting bar.
◯: Can be cut. The cutting residue has a large torsional shape, but the cutting residue does not cling to the cutting bar and can be cut.
△: There is a problem with cutting. The resin is welded to the cutting bar many times during cutting, but the cut is completed.
×: Cannot be cut. A large amount of resin is welded to the cutting bar during cutting and cutting cannot be continued.

(5) Polishability evaluation Three resin test pieces molded into a 20 mm square and 4 mm thickness using a heating press machine (IMC-11D2-C, manufactured by Imoto Seisakusho Co., Ltd.) were prepared for each sample and automatically polished. The sample holder for the machine was attached to the bottom surface with double-sided tape at a position where the force was evenly applied to the three points. Set the holder in an automatic rotary polishing machine (Automet250 & Ecomet250, manufactured by Buehler Co., Ltd.), water-resistant polishing paper # 800 for 30 seconds, # 1500 for 30 seconds, # 3000 for 60 seconds, and Buffalox liquid polishing agent (alumina) on a buffing cloth. Suspension 0.3um) was applied and polished for 60 seconds. The automatic rotary grinding machine was set under the conditions of a head rotation speed of 40 rpm, a base rotation speed of 300 rpm, and an overall load of 6 Lbs. The polished surface of the test piece was visually observed and observed with a laser microscope (KEYENCE Co., Ltd., VK-9700) for evaluation. The objective lens of the laser microscope used was 20 times. The evaluation criteria are shown below.

⊚: A smooth polished surface is formed, and there are almost no polishing scratches even when observed with a laser microscope.
◯: A smooth polished surface is formed visually, but when observed with a laser microscope, some polishing scratches are found.
Δ: A smooth polished surface is formed visually, but when observed with a laser microscope, polishing scratches are slightly frequently made.
X: Innumerable polishing scratches are visually confirmed. When observed with a laser microscope, there are countless polishing scratches, from large scratches to small scratches.

1-4. Measurement / Evaluation Results Table 2 summarizes the measurement / evaluation results for the thermoplastic resins A to K.

As shown in Table 2, the thermoplastic resins E to H (Reference Examples 1 to 4) corresponding to the specific polyesters have a deflection temperature under load (HDT) of 85 ° C. or higher and a Rockwell hardness (HRL) of 90. As described above, the bending strength was 99 MPa or more, the machinability evaluation was ◯, and the greasability evaluation was ◯, indicating good physical properties. In particular, the thermoplastic resin H containing only naphthalene dicarboxylic acid as a dicarboxylic acid component and cyclohexanedimethanol as a third diol component shows the highest values in terms of deflection temperature under load, rockwell hardness and bending strength. ..

On the other hand, even a polyester resin is a specific polyester because it contains only terephthalic acid as a dicarboxylic acid component and does not use a dicarboxylic acid compound (B1) having a polycyclic aromatic hydrocarbon skeleton and / or an ester thereof (B1'). None of the thermoplastic resins A to D (Reference Comparative Examples 1 to 4) having a Rockwell hardness of 90 or more, and the bending strength was lower than that of the Reference Example. In addition, the evaluation of machinability was x, a large amount of resin was welded to the cutting bar, cutting could not be continued, and the greasiness evaluation was also Δ.

Further, I (Reference Comparative Example 5), which is a PMMA resin for a denture base, had an evaluation of machinability and greasability of ⊚, but a bending strength of 66 MPa, which was the lowest, and the strength was insufficient.

Further, the machinability of J (Reference Comparative Example 6), which is a PET resin for denture bases not corresponding to the specific polyester, was evaluated as Δ, and the resin was welded to the cutting bar many times during cutting. In addition, the evaluation of polishability was x, and innumerable polishing scratches were visually confirmed. Further, the bending strength was 81 MPa, which was a low value as compared with Reference Examples 1 to 4.

Furthermore, the greasiness evaluation of K (Reference Comparative Example 6), which is a polyester resin for denture bases that does not correspond to the specific polyester, was x, and innumerable polishing scratches were visually confirmed. Further, the bending strength was 75 MPa, which was a low value as compared with Reference Examples 1 to 4.

2. 2. Examples 1 to 13 and Comparative Examples 1 to 5
Next, the thermoplastic resin for dentures of the present invention will be described with reference to Examples and Comparative Examples, but the present invention is not limited thereto. The evaluation samples used in Examples and Comparative Examples were prepared by press molding using a thermoplastic resin composition obtained by blending the commercially available thermoplastic resins shown below alone or in a predetermined combination and ratio, and (meth) acrylate. The adhesiveness to the hard lining material and the soft silicone lining material was evaluated. The details are shown below.

2-1. Thermoplastic resin (1) Specific polyester The above E to H. That is,
・ E: Artesta SN1500 (manufactured by Mitsubishi Gas Chemical Company, Inc.)
・ F: Artesta SN3000 (manufactured by Mitsubishi Gas Chemical Company, Inc.)
・ G: Artesta SN4500 (manufactured by Mitsubishi Gas Chemical Company, Inc.)
-H: Artesta SH (manufactured by Mitsubishi Gas Chemical Company, Inc.).

(2) Specified amorphous resin ・ L: Hard polyvinyl chloride (Hard Sanner Compound SC-2100 manufactured by Sun Arrow Kasei Co., Ltd.)
-M: Polystyrene (GPPS HF77 manufactured by PS Japan Corporation)
・ N: PMMA (Acrylic VH001 manufactured by Mitsubishi Chemical Corporation)
・ O: ABS (Stylak 026 manufactured by Asahi Kasei Corporation)
-P: Polycarbonate (Teijin Co., Ltd. Panlight L-1225Y)
-Q: Polycarbonate made from isosorbide (DURABIO D7340 manufactured by Mitsubishi Chemical Corporation)
-R: Modified polyphenylene ether (Yupiace AH80 manufactured by Mitsubishi Engineering Plastics Co., Ltd.)
-S: Glycol-modified polyethylene terephthalate (PET-G GN071 manufactured by Eastman Chemical Company).

(3) Amorphous thermoplastic resin other than the specific amorphous resin (hereinafter, also referred to as "non-specific amorphous resin").
・ T: Polysalphon (BASF European Company Ultra Zone S2010)
-U: Cycloolefin polymer (ZEONEX 790R manufactured by Zeon Corporation).

To determine whether the amorphous thermoplastic resin corresponds to the specific amorphous resin or the non-specific amorphous resin, one pellet is immersed in 1 ml of ethyl acetate at 37 ° C for each ATR. After 24 hours, the resin was visually observed, and the one that was completely required was ◎, the one that was partially dissolved and the shape collapsed, the one that showed obvious volume expansion due to swelling, and the one that showed only cloudiness. Was designated as Δ, those showing no change were designated as ×, those marked with ⊚ and ◯ were designated as specific amorphous resins, and those marked with Δ and × were designated as non-specific amorphous resins. For reference, Table 3 shows the evaluation results of the solubility or swelling property of various ATRs in ethyl acetate, the deflection temperature under load, and the bending strength.

2-2. Preparation of sample for evaluation Using each of the vacuum-dried resins, they are melt-mixed as they are (Comparative Example 1) or mixed (Examples 1 to 13 and Comparative Examples 2 to 5) so as to have the composition shown in Table 4. It was smelted and pelletized. Specifically, using a twin-screw extruder (HAAKE process11 manufactured by Thermo Fisher Scientific Co., Ltd.), the barrel temperature is 280 ° C., the die temperature is 240 ° C., and the screw is melt-kneaded at a rotation speed of 50 rpm to 150 rpm. The discharged blend resin was cooled with water and then pelletized using a pelletizer.

Next, using the obtained pellets, a heating press (IMC-11D2-C manufactured by Imoto Seisakusho Co., Ltd.) and a mold made of SUS were used to form a smooth plate-shaped test piece 1 having a size of 15 mm square and a thickness of 2 mm without bubbles. A smooth plate-shaped test piece 2 having a square size of 2 cm and a thickness of 5 mm; and a smooth plate-shaped test piece 3 having a thickness of 15 mm × 30 mm and a thickness of 2 mm;

2-3. Evaluation method (1) Evaluation of adhesiveness to (meth) acrylate-based hard backing material The plate-shaped test piece 1 is adhered to a 1.5 cm square, 2 mm thick SUS plate and lined, and the surface of the resin is #. An adherend was prepared by polishing with 800 water-resistant abrasive paper. Tokuyama Maribase III Normal (manufactured by Tokuyama Dental Co., Ltd.) was used as the (meth) acrylate-based hard backing material, and the rebase adhesive (manufactured by Tokuyama Dental Co., Ltd.), which is an ethyl acetate-containing primer, was used as the adhesive. A double-sided tape having a hole with a diameter of 3 mm was attached to the surface of the adherend to define the adhesive area, and the rebase adhesive was applied with a brush. A 0.5 mm thick paraffin wax having a hole with a diameter of 8 mm was attached from above so as to be concentric with the hole having a diameter of 3 mm, and used as a simulated repair part. A rice cake-like product obtained by kneading Tokuyama Maribase III normal powder and liquid so as to have a P / L ratio of 1.7 was filled in the simulated repair section, and lightly pressed with a polypropylene film from above. After allowing Tokuyama Maribase III Normal to cure under a wet condition of 37 ° C. for 1 hour, the test piece was immersed in water at 37 ° C. for 24 hours. The metallic attachment used in the tensile test was adhered on the Tokuyama Maribase III normal of the test piece taken out. The tensile strength was measured by setting the test piece on a precision universal testing machine (AG-Xplus50kN, manufactured by Shimadzu Corporation) and under the condition of a crosshead speed of 2 mm / min. In the test, 5 measurements were made for one sample, and the average value was taken as the tensile strength.

(2) Evaluation of Adhesiveness to Silicone-based Soft Backing Material The surface of the plate-shaped test piece 2 was polished with # 800 water-resistant abrasive paper to form a set of two adherends. Softliner Tough Medium (manufactured by Tokuyama Dental Co., Ltd.) was used as the silicone-based soft backing material, and the attached adhesive primer, which is an ethyl acetate-containing primer, was used as the adhesive. The adhesive primer attached to Softliner Tough Medium was thinly and evenly applied on the surfaces of the two adherends with a disposable brush. A 3 mm-thick fluororesin (polytetrafluoroethylene) mold with a hole of 10 mm in diameter was placed on one of the two adherends to form a simulated repair section. The soft liner tough medium is kneaded with a mixing tip, filled in the simulated repair part, and the adhesive-applied side of another adherend is placed on it so as to be in contact with the backing material and pressure-welded. bottom. After allowing the softliner tough medium to cure under a wet condition of 37 ° C. for 1 hour, the test piece was immersed in water at 37 ° C. for 24 hours. After that, the metallic attachments used in the tensile test were adhered to the upper and lower sides of the taken-out test piece, that is, to both back sides of the adherend. For the measurement of tensile strength, the test piece was set in a precision universal testing machine (AG-Xplus50kN, manufactured by Shimadzu Corporation), and the metal attachment was subjected to a tensile test on both sides under the condition of a crosshead speed of 5 mm / min. In the test, four measurements were made for one sample, and the average value was taken as the tensile strength. In this test, the upper limit of tensile strength is as low as 2.0 to 3.0 MPa. This is because it is derived from the strength of the soft backing material used in the test. Therefore, it is appropriate to judge the adhesiveness in this test by the fractured form. If the adhesion is good, the soft backing material causes bulk fracture, and if the adhesion is insufficient, the interface fracture occurs between the adherend and the soft backing material. Therefore, the adhesiveness was evaluated by bulk fracture or interface fracture. ..

(3) Flexural strength measurement Using the plate-shaped test piece 3, the measurement was performed in the same manner as the bending strength measurement of the reference example.

2-4. Evaluation Results Table 4 shows the evaluation results of Examples and Comparative Examples. The "addition amount" in Table 4 represents the blending amount (parts by mass) of the amorphous thermoplastic resin (specific amorphous resin or non-specific amorphous resin) with respect to 100 parts by mass of the specific polyester.

As shown in Table 4, in Examples 1 to 13 using the thermoplastic resin composition for dentures of the present invention, as is clear from the comparison with Comparative Example 1, the original characteristics of the specific polyester are maintained. , The adhesiveness to the backing material is improved. On the other hand, in Comparative Examples 2 and 3 in which the non-specific amorphous resin is blended, the effect of improving the adhesiveness to the backing material is not observed. Further, in Comparative Example 4 in which 1 part by mass of the specific amorphous resin was blended with 100 parts by mass of the specific polyester, the effect of improving the adhesiveness was not observed, and in Comparative Example 4 in which 50 parts by mass of the specific amorphous resin was blended. In No. 5, a remarkable decrease in physical properties was observed.

Claims (4)

A thermoplastic resin composition for dentures used as a material for dentures.
Thermoplastic polyester resin: 100 parts by mass and amorphous thermoplastic resin: 5 to 25 parts by mass.
The thermoplastic polyester resin is a polyester resin obtained by polycondensing a diol component (A) and a dicarboxylic acid component (B) at a ratio of 1 mol: 1 mol.
The diol component (A) contains spiroglycol (A1) and ethylene glycol (A2) having a cyclic acetal skeleton.
The contents of the above (A1) and the above (A2) based on the total number of moles of all the diol compounds contained in the diol component (A) are (A1): 15 to 95 mol% and (A2), respectively. : 5 to 85 mol% or less, and the total content of the above (A1) and the above (A2) is 20 to 100 mol% or less.
The dicarboxylic acid component (B) contains a dicarboxylic acid compound (B1) having a polycyclic aromatic hydrocarbon skeleton and / or an ester thereof (B1').
The total content of the (B1) and the (B1') based on the total number of moles of all the dicarboxylic acid compounds contained in the dicarboxylic acid component (B) is 15 to 100 mol%.
The amorphous thermoplastic resin is at least one selected from the group consisting of polyvinyl chloride, polystyrene, polymethylmethacrylate, acrylonitrile-butadiene-styrene copolymer resin, polycarbonate, modified polyphenylene ether and glycol-modified polyethylene terephthalate. ,
A thermoplastic resin composition for dentures, characterized in that. The thermoplastic resin composition for a denture according to claim 1, wherein the dicarboxylic acid compound (B1) is a naphthalene dicarboxylic acid. Claim 1 or 2 that the amorphous thermoplastic resin is an amorphous thermoplastic resin having a deflection temperature under load measured according to the method A (1.8 MPa) of ISO75 (JIS K7191) in the range of 60 to 150 ° C. The thermoplastic resin composition for artificial teeth according to. It has a denture part with artificial teeth fixed to the partial floor and a clasp for attaching the denture part to the hook tooth.
At least a part of the partial floor and the clasp consist of a molded product of the thermoplastic resin composition for dentures according to any one of claims 1 to 3.
A non-metal clasp denture featuring that.