Intraoral adhesive film and method for manufacturing same

Abstract

[Problem] To provide an intraoral adhesive film having both adhesiveness and sustained release properties. [Solution] An intraoral adhesive film 10 is formed of a base material constituting a film-shaped base portion, and various components are kneaded into the base material. The base material is a main material for forming the intraoral adhesive film 10, and mainly contains a water-soluble gelling polymer and a binder. In addition, the surface and cross-section of the base material are porous. The intraoral adhesive film 10 is attached to the inside of the mouth, for example, on the palate, under the tongue, or on the gingiva, and is disintegrated by moisture contained in saliva to release ingredients.

Description

Oral Adhesive Film and Method for Producing the Same

[0001] This invention relates to an oral adhesive film and a method for producing the same, and more particularly to a sustained-release oral adhesive film.

[0002] Conventionally, there are edible films such as film preparations, film-like confections, film-like oral care products, and film-like cooling agents. For example, Patent Document 1 describes an oral adhesive film containing a drug in a water-soluble base. Also, in the field of tablets, there are sustained-release tablets in which the components contained in the tablets are gradually released. In order to control the sustained release of the sustained-release tablets, a sustained-release polymer such as a water-soluble gelling polymer may be used.

[0003] Japanese Patent Laid-Open No. 61-280423

[0004] In order to form the above-mentioned conventional oral adhesive film into a film shape, a casting method is used. In the casting method, a material for forming a film is dispersed or dissolved in a large amount of liquid, the liquid is spread, and the material for forming a film is thinly extended and then dried to produce an oral adhesive film. Even if a water-soluble gelling polymer is used for the purpose of imparting sustained release to such an oral adhesive film, the water-soluble gelling polymer is difficult to disperse or dissolve in a liquid, and it is difficult to blend a large amount of the water-soluble gelling polymer. Therefore, the release suppression of the drug is insufficient, and the sustained release may not be controlled.

[0005] This invention has been made to solve the above-mentioned problems, and an object thereof is to provide an oral adhesive film that uses a water-soluble gelling polymer as both an adhesive material and a sustained-release material and controls the sustained release while having adhesiveness.

[0006] In order to achieve the above object, a first invention is an oral adhesive film comprising a base material constituting a film-shaped base and components kneaded into the base material, the base material containing a binder and a water-soluble gelling polymer and having a porous surface and cross section.

[0007] With this configuration, when applied to the oral cavity, saliva enters the porous gaps, causing the water-soluble gelling polymer to gel and obtain good adhesion. As a result, the oral cavity adhesive film possesses both adhesion and sustained-release properties derived from the water-soluble gelling polymer.

[0008] The second invention is an oral cavity adhesive film in which, in the first invention, the water-soluble gelling polymer is hypromellose.

[0009] With this configuration, hypromellose exhibits adhesive properties upon contact with water, resulting in an oral cavity adhesive film with good adhesion and sustained release properties.

[0010] The third invention is an oral cavity adhesive film in which, in the second invention, the hypromellose content is 1 to 50% by weight of the sum of the weight of the base material and the weight of the component.

[0011] With this composition, if the hypromellose content is between 1% and 50% by weight, an oral cavity adhesive film with appropriate tackiness and sustained release properties is obtained.

[0012] The fourth invention is an intraoral adhesive film in the first invention, wherein the substrate is a porous surface and cross-section having pores with a diameter of 1 μm to 100 μm.

[0013] With this configuration, when the film is applied to the inside of the mouth, the moisture from saliva easily penetrates into the oral cavity adhesive film, and the moisture and water-soluble gelling polymer come into contact more easily, resulting in an oral cavity adhesive film with better adhesion.

[0014] The fifth invention is an intraoral adhesive film in the first invention, wherein the substrate has a porous surface and cross-section with a porosity of 10 to 50%.

[0015] With this configuration, when the film is applied to the inside of the mouth, the moisture from saliva easily penetrates into the oral cavity adhesive film, and the moisture and water-soluble gelling polymer come into contact more easily, resulting in an oral cavity adhesive film with better adhesion.

[0016] The sixth invention is an intraoral adhesive film in which, in the first invention, the base material further comprises crystalline cellulose as an excipient.

[0017] With this configuration, the oral cavity adhesive film becomes viscous due to the intermolecular interactions of crystalline cellulose, resulting in an oral cavity adhesive film that is less prone to cracking.

[0018] The seventh invention is a method for manufacturing an intraoral adhesive film, comprising: a kneading step of kneading a substrate containing a binder and a water-soluble gelling polymer with an edible liquid to form a plastic solid containing the liquid; an extrusion molding step of extruding the solid from a mold to plastically deform the solid and impart a predetermined cross-sectional shape to the solid; a wet-drying step of wetting the solid having the predetermined cross-sectional shape; and a step of slicing the wet-dried solid into a film shape of a predetermined thickness with a blade to obtain an intraoral adhesive film having a porous surface and cross-section.

[0019] With this configuration, a porous oral cavity adhesive film can be manufactured. When applied to the oral cavity, saliva enters the porous gaps, causing the water-soluble gelling polymer to gel and obtain good adhesion. Thus, the oral cavity adhesive film possesses both adhesion and sustained-release properties derived from the water-soluble gelling polymer.

[0020] According to this invention, an intraoral adhesive film is obtained that possesses both adhesiveness and sustained-release properties.

[0021] This is a schematic plan view of an intraoral adhesive film according to an embodiment of this invention. This is a schematic plan view of an intraoral adhesive film according to an embodiment of this invention. This is a flowchart showing an example of a method for manufacturing an intraoral adhesive film according to an embodiment of this invention. This is a schematic diagram illustrating the slicing process of a method for manufacturing an intraoral adhesive film according to an embodiment of this invention. This is a partially enlarged cross-sectional view illustrating the relationship between a blade and a pressing plate. This is an electron microscope image of a cross-section of an intraoral adhesive film according to an embodiment of this invention, magnified 500 times. This is an electron microscope image of the surface of an intraoral adhesive film according to an embodiment of this invention, magnified 300 times. This is an electron microscope image of a cross-section of commercially available product A, magnified 1000 times. This is an electron microscope image of the surface of commercially available product A, magnified 1000 times. This is an electron microscope image of a cross-section of commercially available product B, magnified 1000 times. This is an electron microscope image of the surface of commercially available product B, magnified 1000 times. This is an electron microscope image of a cross-section of commercially available product C, magnified 1000 times. This is an electron microscope image of the surface of commercially available product C, magnified 1000 times. This graph plots the content of the water-soluble gelling polymer on the horizontal axis and the average disintegration time of the oral cavity adhesive film on the vertical axis, according to an embodiment of the present invention. This figure illustrates the evaluation of sustained release properties by adjusting the content of the water-soluble gelling polymer in the oral cavity adhesive film according to an embodiment of the present invention. This graph plots the thickness of the oral cavity adhesive film on the horizontal axis and the average disintegration time of the oral cavity adhesive film on the vertical axis, according to an embodiment of the present invention. This figure illustrates the evaluation of sustained release properties by adjusting the thickness of the oral cavity adhesive film according to an embodiment of the present invention.

[0022] An oral cavity adhesive film 10 according to an embodiment of this invention will be described with reference to the figures.

[0023] Referring to Figure 1, the oral cavity adhesive film 10 according to an embodiment of this invention is, for example, circular in shape in plan view. Referring to Figure 2, the thickness t of the oral cavity adhesive film 10 is, for example, 50 μm to 400 μm. The oral cavity adhesive film 10 is formed from a base material that constitutes the base of the film shape, and various components are kneaded into the base material. The base material is the main material for forming the oral cavity adhesive film 10 and mainly contains a water-soluble gelling polymer and a binder. The oral cavity adhesive film 10 is attached to the inside of the mouth, for example, the palate, under the tongue, and on the gums, and disintegrates due to the moisture contained in saliva, releasing its components.

[0024] The oral cavity adhesive film 10 has a porous surface and cross-section. Because the oral cavity adhesive film 10 has a porous surface and cross-section, when it is attached to the inside of the mouth, saliva enters the porous gaps and the water-soluble gelling polymer gels, resulting in good adhesion. Thus, the oral cavity adhesive film has both adhesion and sustained release properties derived from the water-soluble gelling polymer.

[0025] The diameter of the pores in the porous substrate is preferably between 1 μm and 100 μm. If the pore diameter is 1 μm or larger, when the film is applied to the inside of the mouth, the moisture from saliva can easily penetrate into the oral cavity adhesive film, and the moisture can easily come into contact with the water-soluble gelling polymer, resulting in an oral cavity adhesive film with better adhesion. If the pore diameter is 100 μm or smaller, the oral cavity adhesive film will be less prone to cracking.

[0026] The porosity of the porous substrate is preferably 10 to 50%. If the porosity is 10% or more, when the film is applied to the inside of the mouth, the moisture from saliva easily penetrates into the oral cavity adhesive film, and the moisture and water-soluble gelling polymer come into contact easily, resulting in an oral cavity adhesive film with better adhesion. If the porosity is 50% or less, the oral cavity adhesive film will be less prone to cracking.

[0027] The water-soluble gelling polymer imparts sustained-release properties and tackiness to the oral cavity adhesive film 10. Examples of water-soluble gelling polymers include hypromellose, hydroxyethylcellulose, methylcellulose, sodium carboxymethylcellulose, polyvinylpyrrolidone, polyethylene glycol, polyvinyl alcohol, xanthan gum, guar gum, carrageenan, polyethylene oxide, and carboxyvinyl polymer, with hypromellose being particularly preferred. Using hypromellose results in an oral cavity adhesive film 10 with superior sustained-release capabilities. The content of the water-soluble gelling polymer and hypromellose is preferably 1 to 50% by weight relative to the weight of the oral cavity adhesive film (the sum of the weight of the base material and the weight of the components). If the content of the water-soluble gelling polymer and hypromellose is 1% to 50%, an oral cavity adhesive film with appropriate tackiness and sustained-release properties is obtained.

[0028] The binder enhances the strength of the oral cavity adhesive film 10. Examples of binder materials include amylopectin, sodium alginate, pregelatinized starch, carmellose, carmellose sodium, agar, glycerin, crystalline cellulose, high molecular weight polyvinylpyrrolidone, wheat starch, rice starch, sucrose fatty acid ester, purified gelatin, purified shellac, purified sucrose, gelatin, soy lecithin, low-substituted hydroxypropyl cellulose, dextrin, concentrated glycerin, crystalline cellulose, hydroxyethyl cellulose, hypromellose, pullulan, pectin, polysorbate, macrogol, D-mannitol, and methylcellulose.

[0029] In addition to a water-soluble gelling polymer and a binder, the base material can also contain edible organic compounds or edible inorganic compounds. Examples of edible organic compounds include edible carbohydrates, edible proteins, and edible fats. Examples of edible carbohydrates include edible disaccharides, edible polysaccharides, edible sugar alcohols, and edible dietary fiber. Examples of edible polysaccharides include alginic acid, sodium alginate, pregelatinized starch, agar, xanthan gum, potato starch, cellulose, and pullulan. Examples of edible dietary fiber include pectin and cellulose. Examples of edible disaccharides include refined sucrose. Examples of edible sugar alcohols include sorbitol. Examples of edible proteins include gelatin. Furthermore, examples of their edible derivatives include derivatives of carbohydrates, cellulose derivatives, derivatives of polyvinyl alcohol, and derivatives of sorbitol. Examples of carbohydrate derivatives include sucrose fatty acid esters. Cellulose derivatives include ethylcellulose and carmellose (CMC). Derivatives of sorbitol include sorbitan and sorbitan fatty acid esters (polysorbate).

[0030] Various materials can be incorporated into the base material as components, depending on the purpose, within the oral cavity adhesive film 10. For example, these include medicinal components to give the oral cavity adhesive film 10 a medicinal function, flavoring components to give the oral cavity adhesive film 10 a taste, pigment components to give the oral cavity adhesive film 10 color, nutritional components (including supplements) to provide nutrients to the oral cavity adhesive film 10, fragrance components to give the oral cavity adhesive film 10 a scent, and additives to adjust the physical properties of the oral cavity adhesive film 10. Examples of additives include excipients, disintegrants, flavoring agents, wetting agents, colorants, and emulsifiers.

[0031] The excipient is used to increase the volume of the oral cavity adhesive film 10 to a size that is easy to handle. Examples of excipient materials include alginic acid, sodium alginate, pregelatinized starch, ethylcellulose, carrageenan, carmellose, carmellose sodium, agar, glycerin, croscarmellose sodium, crospovidone, magnesium silicate, crystalline cellulose, wheat flour, wheat starch, rice flour, rice starch, titanium dioxide, sucrose fatty acid ester, refined sucrose, gelatin, skim milk powder, talc, dextran, dextrin, potato starch, pullulan, pectin, polysorbate, macrogol, maltose, and methylcellulose. It is particularly preferable to include crystalline cellulose. By including crystalline cellulose as an excipient in the base material, the oral cavity adhesive film becomes viscous due to the intermolecular interactions of the crystalline cellulose, making it less prone to cracking even if it is a porous oral cavity adhesive film.

[0032] The disintegrant imparts disintegration properties to the oral cavity adhesive film 10. Examples of materials for the disintegrant include alginic acid, pregelatinized starch, carmellose, carmellose sodium, agar, croscarmellose sodium, crospovidone, crystalline cellulose, wheat starch, rice starch, sucrose fatty acid ester, gelatin, dextrin, corn starch, potato starch, hydroxypropyl cellulose, polysorbate, macrogol, magnesium aluminometasilicate, methylcellulose, and sodium lauryl sulfate.

[0033] The flavoring agent adjusts the taste of the oral cavity adhesive film 10. Examples of flavoring agent ingredients include aspartame, DL-alanine, erythritol, reduced maltose syrup, xylitol, citric acid hydrate, sodium citrate hydrate, glycerin, succinic acid, sodium succinate, acetic acid, saccharin, tartaric acid, sodium tartrate, sucralose, thaumatin, sodium bicarbonate, chili pepper, trehalose, sucrose, honey, povidone, D-mannitol, and menthol.

[0034] The humectant prevents the oral cavity adhesive film 10 from drying out and improves the flexibility of the oral cavity adhesive film 10. Examples of materials for the humectant include reduced starch syrup, glycerin, sucrose fatty acid ester, D-sorbitol, propylene glycol, polysorbate, macrogol, and methylcellulose.

[0035] The coloring agent is used to color the oral cavity adhesive film 10. Examples of coloring agent materials include titanium dioxide, food coloring, and talc.

[0036] Emulsifiers are used to ensure that ingredients are mixed well. Examples of emulsifier materials include polysorbate, refined soy lecithin, medium-chain triglyceride, and sodium lauryl sulfate.

[0037] Next, an overview of the method for manufacturing an intraoral adhesive film according to an embodiment of this invention will be explained with reference to Figure 3.

[0038] First, the materials used in the manufacture of the oral cavity adhesive film 10 are weighed (step S1). The materials used in the manufacture of the oral cavity adhesive film 10 mainly consist of a base material that constitutes the base of the oral cavity adhesive film 10, an edible liquid for solidifying the base material to form a solid, and components necessary for the purpose of the oral cavity adhesive film 10. In addition to these main materials, auxiliary materials may be added. In step S1, the base material, edible liquid, and predetermined components that should be contained in a predetermined amount of solid 15 are weighed. The base material, edible liquid, and predetermined components may each be of one type or multiple types. If the oral cavity adhesive film 10 contains multiple components, such as a first component, a second component, etc., they are weighed separately, for example. Examples of edible liquids include water, edible alcohol, edible glycol, glycerin, and edible oils and fats. Examples of edible alcohols include ethyl alcohol. Examples of edible glycols include propylene glycol. The amount of edible liquid is, for example, 35% or less of the mass of the base material. If the mass of edible liquid is too large, the extruded solid 15 may become too soft or stick to the slicing tool, making slicing difficult.

[0039] Next, the solid material to be sliced ​​is prepared (step S2). The material is prepared to be suitable for input into the kneader during the subsequent mixing process. Material preparation may involve, for example, adding a base material and components to an edible liquid.

[0040] The prepared materials are then put into a kneader, for example, and kneaded (step S3). The materials are kneaded in the kneader until the base material, edible liquid, and components are uniformly mixed. By kneading these materials, a clay-like, plastic solid with added water is obtained.

[0041] The solid material 15 obtained by kneading contains air during the kneading process. Therefore, degassing (also called deaeration) may be performed to remove the air from the solid material 15 (step S4). By degassing the solid material 15 and reducing the amount of air bubbles in it, a solid material 15 that is less prone to damage can be obtained. For example, a vacuum-type clay mixer can be used to perform degassing. With a vacuum-type clay mixer, extrusion molding can be performed along with degassing. Furthermore, an extrusion mold can be attached to the tip of a vacuum-type clay mixer. A clay mixer with a mold or nozzle attached in this way is sometimes called an extrusion molding machine.

[0042] Next, the solid 15 is extrusion-molded by an extrusion molding machine (step S5). Referring to FIG. 4, the solid 15 can be extruded from a die of an extrusion molding machine (not shown), the solid 15 can be plastically deformed, and a predetermined cross-sectional shape corresponding to the shape of the die can be imparted to the solid 15. The predetermined cross-sectional shape can be, for example, a circular shape. When the cross-sectional shape is a circular shape, the extruded solid 15 has a cylindrical shape. However, the predetermined cross-sectional shape is not limited to a circular shape, and may be a geometric shape such as a polygonal shape, an elliptical shape, or a star shape. In this case, the extruded solid 15 is also a columnar solid 15 having a bottom surface corresponding to the geometric shape. The height and width of the columnar solid 15 are preferably, for example, 10 mm to 40 mm. If the height and width are 10 mm or more, the oral adhesive film 10 to be produced is easily formed into a film shape, and if the height and width are 40 mm or less, the oral adhesive film 10 to be produced has a size that is easy to take. Also, the predetermined cross-sectional shape has an area of 100 mm ２ ~1600 mm ２ and is preferably. If the area is 100 mm ２ or more, it has a size that is easy to slice in the subsequent process, and if the area is 1600 mm ２ or less, the oral adhesive film 10 to be produced has a size that is easy to take.

[0043] In the extrusion molding process, in order to suppress the temperature of the solid 15 from rising due to the frictional heat generated when the solid 15 is extruded from the die, a cooling unit for cooling the solid 15 may be provided in the extrusion molding machine. By cooling the die by the cooling unit, it is possible to suppress the temperature of the solid 15 from rising. If necessary, by cooling the solid 15 by the cooling unit, the temperature of the solid 15 can be set to, for example, 25°C to 35°C. If the temperature of the solid item 15 is 25°C to 35°C, the solid item 15 can be easily plastically deformed and can have a hardness that can maintain the shape of the solid item 15. The cooling unit can be formed, for example, by a flow path for flowing cooling water through the die of the extrusion molding machine.

[0044] Next, the extruded solid 15 is wet-dried (step S6). The wet-drying process can be carried out, for example, by leaving the solid 15 at a temperature of 20 to 50°C and a humidity of 30 to 70% for 30 minutes to 7 days. Wet-drying equalizes the moisture content in the extruded solid 15. Furthermore, by wet-drying the solid 15, moisture is drawn out from the inside out, resulting in a solid 15 with a porous cross-section.

[0045] Next, the wet and dry solid 15 is sliced ​​with a blade (step S7). Referring to Figure 4, the slicing direction is, for example, a direction intersecting the central axis of the cylindrical solid. In this embodiment of the invention, slicing is performed in a direction perpendicular to the central axis. However, the slicing direction is not limited to a perpendicular direction; for example, it may be sliced ​​diagonally to create an elliptical planar shape. Referring to Figure 5, the blade 40 cuts the solid 15 by physically pressing its thin part against it. The blade 40 may include, for example, a wire stretched like a bowstring. The blade 40 may move in a direction other than the slicing direction, for example, by ultrasonic vibration. Also, referring to Figure 5, a retaining plate 41 may be arranged along the blade 40. It is preferable to use fluororesin for the retaining plate 41. However, the material of this retaining plate 41 is not limited to resin. It is preferable that the surface 42 of the retaining plate 41 has fine irregularities so that the sliced ​​film-shaped solid 101 slides easily. The size d of the gap between the blade 40 and the surface 42 of the press plate 41 is preferably t thicker than the thickness of the film after slicing, and no more than twice the thickness t of the film after slicing, in order to suppress curling of the film-like solid. Suppressing curling of the intraoral adhesive film is expected to enhance the commercial value of the intraoral adhesive film. For solid materials 15 for intraoral adhesive films that do not pose a problem even if they curl, or solid materials 15 made of materials that do not curl easily, the press plate 41 may be removed and the film may be sliced ​​with the blade 40. By slicing the solid material 15 in this way, an intraoral adhesive film 10 can be manufactured.

[0046] Next, the surface and cross-sectional states of the intraoral adhesive film according to the embodiment of the present invention, and the surface and cross-sectional states of commercially available products A, B, and C, which are commercially available intraoral adhesive films, will be described using electron microscope images. Note that commercially available products A, B, and C are intraoral adhesive films manufactured by the conventional casting method. Also, commercially available products A, B, and C do not contain a water-soluble gelling polymer or hypromellose in the base material. FIG. 6 is an electron microscope image obtained by magnifying the cross section of the intraoral adhesive film according to the embodiment of the present invention 500 times. FIG. 7 is an electron microscope image obtained by magnifying the surface of the intraoral adhesive film according to the embodiment of the present invention 300 times. FIG. 8 is an electron microscope image obtained by magnifying the cross section of commercially available product A 1000 times. FIG. 9 is an electron microscope image obtained by magnifying the surface of commercially available product A 1000 times. FIG. 10 is an electron microscope image obtained by magnifying the cross section of commercially available product B 1000 times. FIG. 11 is an electron microscope image obtained by magnifying the surface of commercially available product B 1000 times. FIG. 12 is an electron microscope image obtained by magnifying the cross section of commercially available product C 1000 times. FIG. 13 is an electron microscope image obtained by magnifying the surface of commercially available product C 1000 times. Referring to FIGS. 6 and 7, it can be seen that the surface and cross section of the intraoral adhesive film according to the embodiment of the present invention are porous. Also, the porous pores are uniformly distributed. On the other hand, referring to FIGS. 8 to 13, it can be seen that the intraoral adhesive films of commercially available products A, B, and C all have a dense structure on the surface and cross section. Since the surface and cross section of the intraoral adhesive film according to the embodiment of the present invention are porous, when it is attached in the mouth, the moisture of saliva easily enters the intraoral adhesive film, and the water-soluble gelling polymer serving as the base material and the moisture easily come into contact with each other, so that better adhesiveness can be obtained as compared with commercially available products.

[0047] Next, the sustained release property of the intraoral adhesive film according to the embodiment of the present invention will be described. First, the change in the sustained release property by adjusting the content of the water-soluble gelling polymer will be described. Note that hypromellose was used as the water-soluble gelling polymer.

[0048] Referring to Table 1, oral cavity adhesive films for Examples 1 to 3 and Comparative Example 1 were prepared. Hypromellose was used as the water-soluble gelling polymer. For the oral cavity adhesive film of Comparative Example 1, corn starch was used as the base material instead of the water-soluble gelling polymer. For the oral cavity adhesive films of Examples 1 to 3 and Comparative Example 1, the time it took for them to completely disintegrate after being applied to the mouth was measured to evaluate their sustained release properties. In Table 1, "Water-soluble gelling polymer (%)" is calculated and listed as the weight of the water-soluble gelling polymer relative to the total weight of the oral cavity adhesive film. Also, "Av ± SD" represents the disintegration time of the oral cavity adhesive film, where "Av" is the mean and "SD" is the standard deviation. Figure 15 is a graph plotting the water-soluble gelling polymer content on the horizontal axis and the average disintegration time of the oral cavity adhesive film on the vertical axis.

[0049]

[0050] Referring to Table 1, a comparison of Example 1 and Comparative Example 1 shows that changing the content of the water-soluble gelling polymer from 0% to 1% by weight increases the disintegration time, indicating that sustained release properties can be achieved with only 1% by weight of the water-soluble gelling polymer. Referring to Figure 14, it can be seen that the disintegration time changes in approximately proportion to the content of the water-soluble gelling polymer. This demonstrates that sustained release properties can be easily controlled by adjusting the content of the water-soluble gelling polymer.

[0051] Next, the oral cavity adhesive films of Examples 3 to 5 and Comparative Example 1, as described in Table 1, were placed in a petri dish containing water for 30 minutes to evaluate their sustained release properties. Referring to Figure 15, the left-hand figure shows the state of the oral cavity adhesive film immediately after being placed in the petri dish, and the right-hand figure shows the state of the oral cavity adhesive film after 30 minutes. Comparative Example 1, which does not contain a water-soluble gelling polymer, completely disintegrated after 30 minutes. On the other hand, the oral cavity adhesive films of Examples 3 to 5 did not completely disintegrate even after 30 minutes, indicating that they exhibited better sustained release properties.

[0052] From the above results, it is preferable that the content of the water-soluble gelling polymer be 1 to 50% by weight of the oral cavity adhesive film (total weight of the base material and the components). If the water-soluble gelling polymer is 1% by weight or more, it exhibits sustained release properties and can be easily controlled. If the water-soluble gelling polymer is 50% by weight or less, a sufficient amount of the components can be included and the sustained release properties can be easily controlled. Furthermore, it is more preferable that the content of the water-soluble gelling polymer be 13 to 50% by weight of the oral cavity adhesive film (total weight of the base material and the components). If the water-soluble gelling polymer is 13% by weight or more, it takes 30 minutes or more to disintegrate, thus exhibiting better sustained release properties.

[0053] Next, we will explain how the sustained release properties change when the thickness of the oral cavity adhesive film containing a water-soluble gelling polymer is adjusted. Hypromellose was used as the water-soluble gelling polymer. Referring to Table 2, oral cavity adhesive films for Examples 6 to 8 were prepared. The sustained release properties were evaluated by measuring the time it took for the oral cavity adhesive films of Examples 6 to 8 to completely disintegrate when applied to the mouth. Figure 16 is a graph plotting the thickness of the oral cavity adhesive film on the horizontal axis and the average disintegration time of the oral cavity adhesive film on the vertical axis.

[0054]

[0055] Referring to Table 2, the disintegration time increases as the thickness increases. Also, referring to Figure 16, it can be seen that the disintegration time changes in approximately proportion to the thickness of the intraoral adhesive film, indicating that the sustained release can be easily controlled by adjusting the thickness of the intraoral adhesive film.

[0056] Furthermore, the oral cavity adhesive films of Examples 6 to 8, as described in Table 2, were placed in a petri dish containing water for 30 minutes to evaluate their sustained release properties. Referring to Figure 17, the left-hand figure shows the state of the oral cavity adhesive film immediately after being placed in the petri dish, and the right-hand figure shows the state of the oral cavity adhesive film after 30 minutes. Since the oral cavity adhesive films of Examples 6 to 8 have not completely disintegrated even after 30 minutes, it can be seen that they all exhibit good sustained release properties.

[0057] Based on the above results, the thickness of the intraoral adhesive film is preferably 200 μm to 400 μm. If the thickness of the intraoral adhesive film is 200 μm to 400 μm, the sustained release can be easily controlled.

[0058] In the evaluation experiments described above, hypromellose was used as an example of a water-soluble gelling polymer, but other water-soluble gelling polymers may also be used.

[0059] Although the oral cavity adhesive film according to the embodiment of the present invention has been described using a circular shape in plan view as an example, it is not limited to a circular shape and may be any desired shape. For example, it may be a geometric shape such as a polygon, ellipse, or star shape.

[0060] 10. Intraoral film 15. Solid matter

Claims

1. An intraoral adhesive film comprising a base material constituting a film-shaped base and components kneaded into the base material, wherein the base material contains a binder and a water-soluble gelling polymer and has a porous surface and cross-section.

2. The oral cavity adhesive film according to claim 1, wherein the water-soluble gelling polymer is hypromellose.

3. The oral cavity adhesive film according to claim 2, wherein the hypromellose content is 1 to 50% by weight of the sum of the weight of the base material and the weight of the component.

4. The oral cavity adhesive film according to claim 1, wherein the substrate has a porous surface and cross-section with pore diameters of 1 μm to 100 μm.

5. The oral cavity adhesive film according to claim 1, wherein the substrate has a porous surface and cross-section with a porosity of 10 to 50%.

6. The oral cavity adhesive film according to claim 1, wherein the substrate further comprises crystalline cellulose as an excipient.

7. A method for producing an intraoral adhesive film, comprising: a kneading step of kneading a substrate containing a binder and a water-soluble gelling polymer with an edible liquid to form a plastic solid containing the liquid; an extrusion molding step of extruding the solid from a mold to plastically deform the solid and impart a predetermined cross-sectional shape to the solid; a wet-drying step of wetting the solid having the predetermined cross-sectional shape; and a step of slicing the wet-dried solid into a film shape of a predetermined thickness with a blade to obtain an intraoral adhesive film having a porous surface and cross-section.

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