JP2025183652A - denture adhesive - Google Patents

Abstract

To provide a denture stabilizer exhibiting superiority in cushioning performance, manufacturing ease, and reduced tendency to adhere to fingers.SOLUTION: A denture stabilizer contains components (1) and (2) below, wherein a content of the component (2) is 4 mass% or more and 7.5 mass% or less: (1) a vinyl acetate resin having an average degree of polymerization of 700 or more and 1100 or less; and (2) a terpolymer having, as constituent components, a lower alkyl acrylate, a lower alkyl methacrylate, and trimethylammonioethyl methacrylate chloride.SELECTED DRAWING: None

Description

Regarding denture adhesives.

Traditionally, denture adhesives have been used to secure dentures in place in the oral cavity. Various types of denture adhesives are known, including cushion-type denture adhesives, also known as tight-fitting denture adhesives, which fill the gap between the denture (mainly the denture base) and the gums, and are used to secure the denture tightly to the gums like a suction cup.

Known examples of adhesive denture fixatives include those containing a vinyl acetate resin as the main base mixed with a solvent such as ethanol (Patent Documents 1 and 2). Patent Document 1 describes a denture fixative containing, as its main components, a low-molecular-weight vinyl acetate resin with an average degree of polymerization of 600-900, a medium-molecular-weight vinyl acetate resin with an average degree of polymerization of 1000-2000, and a high-molecular-weight vinyl acetate resin with an average degree of polymerization of 4000-7000, and further containing a terpolymer composed of a lower alkyl acrylate, a lower alkyl methacrylate, and trimethylammonium ethyl methacrylate chloride. Patent Document 1 thus discloses a denture fixative that combines the three vinyl acetate resins with specific degrees of polymerization as essential components and a specific terpolymer. Patent Document 1 also describes that this denture fixative provides excellent usability, with minimal adhesion to fingers when applied to the back surface of a denture base, and excellent releasability, allowing the entire denture base to be easily peeled off the back surface. Patent Document 2 describes a denture adhesive containing polyethylene glycol and vinyl acetate resin with an average degree of polymerization of 1,100 or less. Patent Document 2 also describes that this denture adhesive is a tight-fitting denture adhesive that is both resistant to dripping and easy to extrude from a container, making it easier to put on dentures during use.

Japanese Patent Application Laid-Open No. 2004-350695 JP 2023-95530 A

It is desirable for denture adhesives to have a suitable cushioning feel in order to reduce the strain on the gums when wearing them. It is also important that the denture adhesive can be manufactured easily during production. For example, if mixing the ingredients is difficult during production, problems such as insufficient mixing can occur, strain can be placed on the mixer, and production efficiency can decrease. Furthermore, since denture adhesives are typically applied to the denture base surface with fingers, it is important that the denture adhesive does not easily adhere to fingers. The inventors have uniquely focused on this issue.

The present disclosure therefore aims to provide a denture adhesive that is excellent in terms of cushioning properties, ease of manufacturing, and resistance to adhesion to fingers.

As a result of extensive research, the present inventors have discovered that by combining a vinyl acetate resin having an average degree of polymerization within a specific range, i.e., (1) a vinyl acetate resin having an average degree of polymerization of 700 to 1100, with (2) a terpolymer having as its constituent components a lower alkyl acrylate, a lower alkyl methacrylate, and trimethylammonium ethyl methacrylate chloride, and by adjusting the content of component (2) to 4% by mass to 7.5% by mass, a denture adhesive excellent in cushioning properties, ease of production, and resistance to adhesion to fingers can be obtained. The present invention was completed through further research based on this finding, and this disclosure encompasses, for example, the following representative inventions.
Item 1. A denture adhesive containing the following components (1) and (2), wherein the content of component (2) is 4% by mass or more and 7.5% by mass or less:
(1) a vinyl acetate resin having an average degree of polymerization of 700 or more and 1100 or less;
(2) A terpolymer having, as constituent components, a lower alkyl acrylate, a lower alkyl methacrylate, and trimethylammonium ethyl methacrylate chloride.
Item 2. The denture adhesive according to Item 1, wherein the content of component (1) in the denture adhesive is 30% by mass or more and 80% by mass or less.

This disclosure makes it possible to provide a denture adhesive that is excellent in terms of cushioning properties, ease of manufacturing, and resistance to adhesion to fingers.

Photographs of the procedure for evaluating the difficulty of adhesion to fingers in Test Example 1 are shown.

The embodiments included in this disclosure are described in more detail below. In this disclosure, "comprise" also means "consist essentially of" or "consist of."

The present disclosure encompasses a denture adhesive containing the following components (1) and (2), with the content of component (2) being 4% by mass or more and 7.5% by mass or less. In the present disclosure, this denture adhesive may be referred to as the "denture adhesive of the present disclosure."
(1) a vinyl acetate resin having an average degree of polymerization of 700 or more and 1100 or less;
(2) A terpolymer having, as constituent components, a lower alkyl acrylate, a lower alkyl methacrylate, and trimethylammonium ethyl methacrylate chloride.

Component (1)
The denture stabilizer of the present disclosure contains (1) a vinyl acetate resin having an average degree of polymerization of 700 to 1100 as an essential component. This vinyl acetate resin may be referred to as "component (1)" in the present disclosure. The average degree of polymerization of the vinyl acetate resin incorporated into the denture stabilizer is not limited as long as it is 700 to 1100, and is preferably 750 to 1100, and more preferably 780 to 1100. Vinyl acetate resins having an average degree of polymerization of 700 to 1100 may be incorporated alone or in combination of two or more. In the present disclosure, the average degree of polymerization of the vinyl acetate resin is a value measured in accordance with JIS K6725-1977, "Testing Methods for Polyvinyl Acetate." The same explanation of the average degree of polymerization of the vinyl acetate resin is provided below.

The content of component (1) in the denture adhesive of the present disclosure is not limited, but examples include 30% by weight or more and 80% by weight or less, preferably 45% by weight or more and 75% by weight or less, and more preferably 55% by weight or more and 75% by weight or less.

Component (2)
The denture adhesive of the present disclosure contains, as an essential component, (2) a terpolymer composed of lower alkyl acrylate, lower alkyl methacrylate, and trimethylammonium ethyl methacrylate chloride. This terpolymer may be referred to as "component (2)" in this disclosure. This terpolymer may also be referred to as an ammonioalkyl methacrylate copolymer. The lower alkyl group constituting component (2) is an alkyl group having 1 to 6 carbon atoms, such as methyl, ethyl, propyl, or butyl. A preferred example of component (2) is a terpolymer composed of ethyl acrylate, methyl methacrylate, and a relatively small amount of trimethylammonium ethyl methacrylate chloride. This preferred terpolymer is known as a random copolymer with a molecular weight of approximately 150,000, commercially available under the trade name "EUDRAGIT® RS100" (manufactured by Rohm GmbH & Co. KG), and therefore this commercially available product is an example. Thus, component (2) is commercially available. The component (2) may be used alone or in combination of two or more.

The content of component (2) in the denture adhesive of the present disclosure is 4% by mass or more and 7.5% by mass or less. The content of component (2) in the denture adhesive is preferably 4% by mass or more and 6.5% by mass or less, and more preferably 4% by mass or more and 6% by mass or less.

The denture adhesive of the present disclosure may contain ethanol. When the denture adhesive of the present disclosure contains ethanol, the ethanol content in the denture adhesive is preferably 1% by mass or more and 40% by mass or less. The ethanol content in the denture adhesive is preferably 5% by mass or more and 30% by mass or less, and more preferably 10% by mass or more and 20% by mass or less. The denture adhesive of the present disclosure preferably contains ethanol.

The denture adhesive of the present disclosure may contain water. When the denture adhesive of the present disclosure contains water, the water content in the denture adhesive is preferably 0.5% by mass or more and 40% by mass or less. The water content in the denture adhesive is more preferably 1% by mass or more and 30% by mass or less, and even more preferably 3% by mass or more and 15% by mass or less. The denture adhesive of the present disclosure preferably contains water.

The denture adhesive of the present disclosure may contain a vinyl acetate resin with an average degree of polymerization of less than 700, provided that the effects of the present disclosure are not impaired. The lower limit of the average degree of polymerization of the vinyl acetate resin is not limited, and examples typically include vinyl acetate resins known in the art, preferably vinyl acetate resins with an average degree of polymerization of 200 or more. Therefore, examples of vinyl acetate resins with an average degree of polymerization of less than 700 include vinyl acetate resins with an average degree of polymerization of 200 or more but less than 700. Vinyl acetate resins with an average degree of polymerization of less than 700 may be used alone or in combination of two or more. When the denture adhesive of the present disclosure contains a vinyl acetate resin with an average degree of polymerization of less than 700, the content of the vinyl acetate resin with an average degree of polymerization of less than 700 in the denture adhesive is preferably greater than 0% by weight and less than 10% by weight. When the denture adhesive contains a vinyl acetate resin with an average degree of polymerization of less than 700, the content of the vinyl acetate resin in the denture adhesive is more preferably greater than 0% by weight and less than 5% by weight, and even more preferably greater than 0% by weight and less than 3% by weight. The denture adhesive of the present disclosure particularly preferably does not contain vinyl acetate resin with an average degree of polymerization of less than 700.

The denture stabilizer of the present disclosure may contain a vinyl acetate resin with an average degree of polymerization exceeding 1100 (hereinafter, sometimes referred to as a "vinyl acetate resin with an average degree of polymerization exceeding 1100"), provided that the effects of the present disclosure are not impaired. The upper limit of the average degree of polymerization of the vinyl acetate resin is not limited, and examples thereof typically include vinyl acetate resins known in the art, preferably vinyl acetate resins with an average degree of polymerization of 7000 or less. Therefore, examples of vinyl acetate resins with an average degree of polymerization exceeding 1100 include vinyl acetate resins with an average degree of polymerization exceeding 1100 and not exceeding 7000. Vinyl acetate resins with an average degree of polymerization exceeding 1100 may be used alone or in combination of two or more. When the denture stabilizer of the present disclosure contains a vinyl acetate resin with an average degree of polymerization exceeding 1100, the content of the vinyl acetate resin with an average degree of polymerization exceeding 1100 in the denture stabilizer is preferably greater than 0% by mass and not greater than 10% by mass. When a vinyl acetate resin with an average degree of polymerization greater than 1100 is contained, the content of the vinyl acetate resin in the denture adhesive is more preferably greater than 0% by mass and less than 5% by mass, and even more preferably greater than 0% by mass and less than 3% by mass. The denture adhesive of the present disclosure particularly preferably does not contain a vinyl acetate resin with an average degree of polymerization greater than 1100.

When the denture adhesive of the present disclosure contains both a vinyl acetate resin with an average degree of polymerization of less than 700 and a vinyl acetate resin with an average degree of polymerization of more than 1100, the total amount of the vinyl acetate resin with an average degree of polymerization of less than 700 and the vinyl acetate resin with an average degree of polymerization of more than 1100 in the denture adhesive is preferably greater than 0% by mass and less than 20% by mass. Furthermore, the total amount in the denture adhesive is more preferably greater than 0% by mass and less than 10% by mass, even more preferably greater than 0% by mass and less than 6% by mass, and especially preferably greater than 0% by mass and less than 3% by mass. It is particularly preferred that the denture adhesive of the present disclosure does not contain a vinyl acetate resin with an average degree of polymerization of less than 700, and does not contain a vinyl acetate resin with an average degree of polymerization of more than 1100.

In addition to the above-mentioned components, the denture adhesive of the present disclosure may contain further optional components as needed, as long as the effects of the present disclosure are not impaired. Examples of optional components include plasticizers, humectants, release enhancers, pH adjusters, emulsifiers, viscosity adjusters, water permeability enhancers, water-insoluble powders, preservatives, metallic soaps, antiseptics, disinfectants, colorants, fragrances, flavoring agents, refreshing agents, sweeteners, and plaque-decomposing enzymes. The optional components may be used alone or in combination of two or more. The amounts of the optional components may also be determined appropriately depending on the purpose.

While not limiting the present disclosure, examples of optional components include plasticizers, such as beeswax, Japan wax, carnauba wax, candelilla wax, and liquid paraffin. Plasticizers may be used singly or in combination of two or more. When the denture adhesive of the present disclosure contains a plasticizer, the content of the plasticizer in the denture adhesive is not limited, but is preferably greater than 0% by mass and less than 20% by mass, and more preferably greater than 0% by mass and less than 10% by mass. The denture adhesive of the present disclosure preferably does not contain a plasticizer.

While not limiting the present disclosure, examples of optional ingredients include humectants such as polyethylene glycol, polypropylene glycol, propylene glycol, glycerin, and sorbitol. A single humectant may be used, or two or more may be used in combination. When the denture stabilizer of the present disclosure contains a humectant, the content of the humectant in the denture stabilizer is not limited, but is preferably greater than 0% by weight and less than 20% by weight, and more preferably greater than 0% by weight and less than 10% by weight. The denture stabilizer of the present disclosure preferably does not contain polyethylene glycol, and more preferably does not contain a humectant.

While not limiting the present disclosure, examples of optional components include release enhancers, such as polybutene, polyisobutylene, calcium carbonate, calcium phosphate, bentonite, silicon dioxide, and dimethylpolysiloxane. These release enhancers may be used alone or in combination. When the denture stabilizer of the present disclosure contains a release enhancer, the content of the release enhancer in the denture stabilizer is not limited, but is preferably greater than 0% by mass and less than 5% by mass, and more preferably greater than 0% by mass and less than 3% by mass. The denture stabilizer of the present disclosure preferably does not contain a release enhancer. While component (2) can be used as a release enhancer, component (2) is not included in the optional release enhancers of the present disclosure. Therefore, the content of component (2) is not included in the above content.

The denture adhesive of the present disclosure can be produced by mixing component (1) and component (2), preferably by mixing component (1) and component (2) with ethanol and water, and optionally adding any of the above-mentioned components. One preferred example of a method for producing the denture adhesive of the present disclosure is to premix component (2) with ethanol and water, and then mix it with component (1), and optionally add any of the above-mentioned components.

The denture adhesive of the present disclosure can be said to be a tight-fitting denture adhesive. Preferred examples of the form of the denture adhesive of the present disclosure include paste-like forms such as creams and gels, similar to conventional tight-fitting denture adhesives.

The container for storing the denture adhesive of the present disclosure is not particularly limited, but a tube container is preferred. The material of the tube container is also not particularly limited, and examples include plastic tubes and plastic-aluminum laminate tubes.

The denture adhesive of the present disclosure is used to attach and fix dentures in a predetermined position in the oral cavity (mainly under the maxilla and/or above the mandible) by creating a tight seal between the dentures and the gums. The dentures in question may be either complete dentures or partial dentures, with complete dentures being preferred. There are no particular restrictions on the material of the denture base (denture base), and it may be either a resin base, a metal base, or the like, with a resin base being a preferred example.

The denture adhesive of the present disclosure can be used in the same manner as known tight-fitting denture adhesives. For example, it can be used by spreading a thin layer of denture adhesive over the entire surface of a dry denture base that comes into contact with the upper or lower jaw. When a denture with denture adhesive applied is placed in the mouth and fitted to the upper or lower jaw, the denture adhesive absorbs the moisture from saliva and contracts, forming a cushion-like shape that adheres tightly to the gums (upper or lower jaw), securing it in place.

According to the present disclosure, as described above, by using components (1) and (2) and incorporating (2) at 4% by mass or more and 7.5% by mass or less, a denture adhesive that is excellent in cushioning properties and resistance to adhesion to fingers can be easily produced.

As such, the denture adhesive of the present disclosure has excellent cushioning properties, reducing the strain on the gums when wearing dentures coated with the denture adhesive. In the present disclosure, the cushioning properties of a denture adhesive can be determined by the loss tangent tanδ (loss modulus G''/storage modulus G'). For denture adhesives of the present disclosure, the loss tangent tanδ (loss modulus G''/storage modulus G') at 25°C is preferably 1.2 or greater and 2.2 or less. By satisfying this range of loss tangent tanδ, the desired cushioning properties can be exhibited. Loss modulus refers to the component of energy generated by external forces and strains in an object that diffuses to the outside, while storage modulus refers to the component that is stored internally. While not limiting the present disclosure, it is more preferable for denture adhesives of the present disclosure to have a loss tangent tanδ at 25°C of 1.4 or greater and 2.0 or less.

In this disclosure, the loss tangent tanδ at 25°C is measured using a rheometer under conditions of parallel plates (25 mmφ), a gap of 1.0 mm, a frequency of 1 Hz, and strains of 0.01 to 100%. The loss modulus (G'') and storage modulus (G') values at a strain of 0.01% are determined, and the value is calculated using the formula loss modulus G'' (Pa) / storage modulus G' (Pa). More detailed information can be obtained by following the evaluation procedures in the test examples described below.

In the denture adhesive of the present disclosure, the value of the loss modulus (G'') at 25°C is generally not limited as long as it satisfies the range of the loss tangent tanδ described above, and may be, for example, 100 to 18,000 Pa, preferably 400 to 15,000 Pa, more preferably 1,000 to 13,000 Pa, and even more preferably 2,800 to 13,000 Pa. By satisfying this range, appropriate cushioning properties can be even more suitably achieved. The method for measuring the loss modulus (G'') at 25°C follows the explanation for the loss tangent tanδ described above.

In the denture adhesive of the present disclosure, the value of the storage modulus (G') at 25°C is generally not limited as long as it satisfies the range of the loss tangent tanδ described above, and may be, for example, 100 to 15,000 Pa, preferably 150 to 12,500 Pa, more preferably 400 to 10,000 Pa, and even more preferably 3,800 to 10,000 Pa. By satisfying this range, appropriate cushioning properties can be more suitably provided. The method for measuring the storage modulus (G') at 25°C follows the explanation for the loss tangent tanδ described above.

The denture adhesive of the present disclosure can also be easily manufactured. For example, if mixing the ingredients is difficult during manufacturing, problems can arise, such as reduced manufacturing efficiency due to difficulty in sufficient mixing, a shorter machine life due to strain on the mixer, and increased manufacturing costs. According to the present disclosure, the ingredients can be easily mixed, as can be seen from the examples described below. Therefore, according to the present disclosure, a denture adhesive with excellent cushioning properties can be easily manufactured. The ease of manufacturing of the denture adhesive of the present disclosure can be determined by following the procedures shown in the test examples described below.

The denture adhesive of the present disclosure is also excellent in that it does not easily stick to fingers. When fitting dentures to the gums, the denture adhesive is usually applied to the denture base with fingers, etc., to make it adhere. If the denture adhesive is prone to sticking to fingers, it becomes difficult to apply the denture adhesive to the denture base. According to the present disclosure, as can be seen from the examples described below, the denture adhesive does not easily stick to fingers, making it easy to apply to the denture base. The degree to which the denture adhesive of the present disclosure does not easily stick to fingers can be determined by following the procedure shown in the test examples described below. According to the present disclosure, a denture adhesive that has excellent cushioning properties and does not easily stick to fingers can be easily manufactured.

The following examples are provided to explain embodiments of the present disclosure in more detail, but the embodiments of the present disclosure are not limited to the examples below.

Test Example 1
1. Preparation of denture adhesive The components shown in Table 1 below were blended in the specified amounts to prepare denture adhesives for Examples 1 to 8 and Comparative Examples 1 to 6. In the table, the blending amounts are shown in mass %. Specifically, the denture adhesives were prepared by pre-mixing component (2) with ethanol and water, and then stirring with Hibismix (registered trademark) until component (1) was uniformly dispersed.

The vinyl acetate resin and the terpolymer (ammonioalkyl methacrylate copolymer) having lower alkyl acrylate, lower alkyl methacrylate, and trimethylammonium ethyl methacrylate chloride as constituent components used in this test example are as follows:
Vinyl acetate resin having an average degree of polymerization of 500: trade name: Sakunoru 05G, manufactured by Denki Kagaku Kogyo Co., Ltd. Vinyl acetate resin having an average degree of polymerization of 780 (component (1)): Sakunoru SN-08H, manufactured by Denki Kagaku Kogyo Co., Ltd. Vinyl acetate resin having an average degree of polymerization of 870 (component (1)): trade name: VINNAPAS B 100 SPECIAL, manufactured by Wacker Chemie AG Vinyl acetate resin having an average degree of polymerization of 1100 (component (1)): trade name: VINNAPAS B 500, manufactured by Wacker Chemie AG Vinyl acetate resin having an average degree of polymerization of 1200: trade name: Sakunoru 12T, manufactured by Denki Kagaku Kogyo Co., Ltd. Ammonioalkyl methacrylate copolymer (component (2)): trade name: Eudragit RS100, manufactured by Rohm GmbH & Co. KG

2. Evaluation Cushioning properties, ease of production, and resistance to adhesion to fingers were evaluated according to the following procedures.

Cushioning properties: For the denture adhesives of Examples 1 to 8 and Comparative Examples 1 to 6, the loss modulus (G") and storage modulus (G') at a strain of 0.01% were measured using a rheometer (viscoelasticity measuring device MCR302, manufactured by Anton Paar Co., Ltd.) under the following conditions, and the loss tangent (tan δ) was calculated according to the following formula. In the table, the loss tangent (tan δ) values are rounded to one decimal place.
Measurement conditions: 25°C, parallel plate (25 mmφ), gap 1.0 mm
Measurement procedure: After leaving the sample to stand (shear rate 0 S ⁻¹ , time 300 seconds), a strain dispersion test (strain γ=0.01 to 100%, frequency f=1 Hz) was performed. The formula for calculating the loss tangent (tan δ) was: loss modulus G″ (Pa)/storage modulus G′ (Pa).

Based on the calculated loss tangent (tan δ), the cushioning properties were evaluated according to the following criteria.
[standard]
◎ (More preferable cushioning): 1.4 or more and 2.0 or less:
○ (preferable cushioning): 1.2 or more and less than 1.4 or more than 2.0 and less than 2.2 △ (with cushioning): 1.0 or more and less than 1.2 or more than 2.2 and less than 2.5 × (no cushioning): 1.0 or less or 2.5 or more

- Ease of manufacturing : Component (2), ethanol, water, and vinyl acetate resin (total 250 kg) were added in that order to a mixer (Hibismix (registered trademark) HM-2P-350 model) according to the blending ratios shown in Table 1, and the load current value applied to the blades when the mixture was heated from room temperature (25°C) to 40°C while stirring and dissolving was measured. Based on the measured load current value, the ease of manufacturing was evaluated according to the following criteria. As the load current value increases, stirring becomes more difficult.

[standard]
◯: Load current value less than 65 A △: Load current value 65 A or more but less than 82 A ×: Load current value 82 A or more

- Difficulty of adhesion to fingers: Seven expert panelists evaluated the ease of adhesion of each denture adhesive to their fingers. Specifically, they washed their hands with commercially available foam hand soap (1-2 pumps) and thoroughly dried them with a Kimtowel. Then, they sprayed 70% ethanol onto their fingers and thoroughly dried them with a Kimtowel. Next, as shown in Figure 1, 0.5-0.6 g of each denture adhesive was placed on their fingers and kneaded or crushed between their fingers to form a ball.

The denture adhesive of Comparative Example 2 was used to determine how difficult it was to stick to fingers, and scores were assigned using the following evaluation points. The sum of the products of each evaluation point and the number of people was calculated. Based on the calculated sum, a rating of 4 points was given. Here, Comparative Example 2 was given a rating of 3.

[Evaluation points]
5: Less adhesive than Comparative Example 2 4: Rather less adhesive than Comparative Example 2 3: Equivalent to Comparative Example 2 2: Rather easier to adhesive than Comparative Example 2 1: Easier to adhesive than Comparative Example 2 [Total]
◎: 29-35
○: 22-28
△: 8 to 21
×: 7 to 14

3. Results The results are shown in Table 1.

The denture adhesives of Examples 1 to 8, which used vinyl acetate resins with an average degree of polymerization of 780, 870, or 1100 and contained component (2) at 4, 4.5, 6, or 7.5% by mass, achieved desirable results in all respects: cushioning, ease of manufacturing, and resistance to adhesion to fingers.

In contrast, the denture adhesive of Comparative Example 1, which was manufactured in the same manner as the denture adhesive of Example 1 except for a reduced content of component (2), did not achieve the desired effect. Specifically, the denture adhesive of Comparative Example 1 uses a vinyl acetate resin with an average degree of polymerization of 870, but the content of component (2) was reduced to 3.5% by mass. The denture adhesive of Comparative Example 1 was rated as fair for cushioning, demonstrating inferior results to Example 1. Furthermore, the denture adhesive of Comparative Example 2, which was manufactured in the same manner as the denture adhesive of Example 1 except for an increased content of component (2), also did not achieve the desired effect. Specifically, the denture adhesive of Comparative Example 2 uses a vinyl acetate resin with an average degree of polymerization of 870, but the content of component (2) was increased to 8% by mass. The denture adhesive of Comparative Example 2 was rated as poor for ease of manufacturing and fair for difficulty of adhesion to fingers.

Furthermore, the denture adhesives of Comparative Examples 3 and 4, in which the content of component (2) was set to 6% by mass and 8% by mass, respectively, and the average degree of polymerization of the vinyl acetate resin blended was reduced to 500, also failed to produce the desired results. Specifically, the cushioning properties of the denture adhesives of Comparative Examples 3 and 4 were rated as x. Furthermore, the denture adhesives of Comparative Examples 5 and 6, in which the content of component (2) was set to 3.5% by mass and 6% by mass, respectively, and the average degree of polymerization of the vinyl acetate resin blended was increased to 1200, also failed to produce the desired results.

From these findings, it was found that the denture adhesives of Examples 1 to 8 were more desirable in all respects, including cushioning, ease of manufacturing, and resistance to adhesion to fingers, compared to Comparative Examples 1 to 6.

Claims (2)

A denture adhesive containing the following components (1) and (2), wherein the content of component (2) is 4% by mass or more and 7.5% by mass or less:
(1) a vinyl acetate resin having an average degree of polymerization of 700 or more and 1100 or less;
(2) A terpolymer having, as constituent components, a lower alkyl acrylate, a lower alkyl methacrylate, and trimethylammonium ethyl methacrylate chloride. The denture adhesive according to claim 1, wherein the content of component (1) in the denture adhesive is 30% by mass or more and 80% by mass or less.