Resin acid-containing composition, antibacterial agent, and method for producing resin acid-containing composition

Abstract

To provide a resin acid-containing composition which elutes a resin acid to water at a high elution rate, and can suppress an insoluble matter, an antibacterial agent, and a method for producing the resin acid-containing composition.SOLUTION: A resin acid-containing composition 10 contains a water-soluble organic matrix 11, and a resin acid 12, wherein the resin acid 12 is dispersed in the water-soluble organic matrix 11. The water-soluble organic matrix 11 contains at least one selected from the group consisting of methyl cellulose, hydroxypropyl methylcellulose and carboxymethyl cellulose. An elution rate of the resin acid 12 to distilled water is 20.0 wt.% or more, which is obtained by measuring a supernatant liquid separated from a resin acid eluted liquid by centrifugal separation, immediately after a resin acid eluted liquid obtained by eluting at least a part of the resin acid 12 to the distilled water is prepared by shaking resin acid immersion water in which the resin acid-containing composition 10 is immersed in distilled water, at a temperature of 37.0±0.5°C for 30 minutes.SELECTED DRAWING: Figure 1

Description

Technical Field

[0001] The present invention relates to a resin acid-containing composition, an antibacterial agent, and a method for producing a resin acid-containing composition.

Background Art

[0002] In recent years, rosin and resin acids contained in rosin (hereinafter, "rosin and resin acids" are simply referred to as "rosin etc.") have attracted attention as materials derived from natural materials. In particular, regarding rosin etc., there are scattered research examples focusing on its antibacterial properties, antiviral properties, and physiological activity functions such as bactericides. If rosin etc. can be used in a liquid state instead of a solid state, it is considered that the physiological activity functions of rosin etc. can be easily utilized because rosin etc. can be supplied in various forms such as spraying, coating, and dropping. However, since rosin etc. are poorly water-soluble compounds, even if these are eluted in water, only a turbid aqueous dispersion can be prepared. Therefore, the functions of rosin etc. as physiologically active substances have not been fully utilized.

[0003] In order to solve such problems, Non-Patent Document 1 examines a method for eluting resin acids in water. Non-Patent Document 1 discloses a resin acid-containing composition in which abietic acid is dispersed as a resin acid in a matrix composed of cellulose nanofibers. When the resin acid-containing composition disclosed in Non-Patent Document 1 is immersed in water and shaken, it has been confirmed that abietic acid dispersed in the matrix shows a high elution rate in water.

Prior Art Documents

Non-Patent Documents

[0004]

Non-Patent Document 1

Summary of the Invention

Problems to be Solved by the Invention

[0005] In the resin acid-containing composition disclosed in Non-Patent Document 1, abietic acid shows a high elution rate in water, but the matrix does not elute in water at all or elutes in water only to the extent of retaining its original form. When such insoluble matters are present, it is considered necessary to remove the insoluble matters when using the resin acid eluate obtained by eluting the resin acid-containing composition in water. Since additional operations such as filtration and centrifugation are required for the removal of the insoluble matters, the convenience of the resin acid eluate deteriorates.

[0006] Therefore, an object of the present invention is to provide a resin acid-containing composition, an antibacterial agent, and a method for producing a resin acid-containing composition that can elute resin acid at a high elution rate and suppress insoluble matters when eluted in water.

Means for Solving the Problems

[0007] As a result of intensive studies, the present inventors have newly found that in a resin acid-containing composition in which resin acid is dispersed in a water-soluble organic matrix, when the resin acid-containing composition is immersed and shaken, the resin acid shows a high elution rate and almost no insoluble matters of the matrix remain, and thus the present invention has been completed.

[0008] Viewed from one aspect, the present invention A resin acid-containing composition comprising a water-soluble organic matrix and a resin acid, wherein the resin acid is dispersed in the water-soluble organic matrix, the water-soluble organic matrix contains at least one selected from the group consisting of methyl cellulose, hydroxypropyl methyl cellulose, and carboxymethyl cellulose, provide a resin acid-containing composition.

[0009] Viewed from another aspect of the present invention, A resin acid-containing composition comprising a water-soluble organic matrix and a resin acid, wherein the resin acid is dispersed in the water-soluble organic matrix, Immediately after preparing a resin acid eluate in which at least a part of the resin acid is eluted into the distilled water by shaking for 30 minutes at a temperature of 37.0 ± 0.5 ° C. with respect to the resin acid immersion water obtained by immersing the resin acid-containing composition in distilled water, by centrifugation, Provided is a resin acid-containing composition having an elution rate of the resin acid into the distilled water of 20.0% by weight or more, measured using the supernatant separated from the resin acid eluate.

[0010] Viewed from another aspect of the present invention, Provide an antibacterial agent containing any one of the above resin acid-containing compositions.

[0011] Viewed from another aspect of the present invention, Preparing a resin acid-containing liquid containing a resin acid and an organic solvent, Using the resin acid-containing liquid to prepare a mixed liquid containing the resin acid, the organic solvent, a water-soluble organic matrix, and water, Removing at least a part of the organic solvent from the mixed liquid to obtain a resin acid-containing composition containing at least the resin acid and the water-soluble organic matrix, Provide a method for producing a resin acid-containing composition, comprising:

Effects of the Invention

[0012] According to the present invention, when a resin acid-containing composition is eluted in water, the resin acid can be eluted at a high elution rate and the insoluble matter can be suppressed.

Brief Description of the Drawings

[0013]

Figure 1

Figure 2

Figure 3

Mode for Carrying Out the Invention

[0014] Hereinafter, embodiments of the present invention will be described. However, the following description is not intended to limit the present invention to specific embodiments. In this specification, the upper and lower limits of the numerical ranges described below can be arbitrarily combined in both cases where the upper and lower limits are described individually and where the upper and lower limits are described as a range.

[0015] [Resin Acid-Containing Composition] FIG. 1 schematically shows a resin acid-containing composition 10 according to an embodiment of the present invention. The resin acid-containing composition 10 of this embodiment includes a water-soluble organic matrix 11 and a resin acid 12. The resin acid 12 is dispersed in the water-soluble organic matrix 11.

[0016] In the resin acid-containing composition 10 of this embodiment, the water-soluble organic matrix 11, together with the resin acid 12, elutes substantially the entire resin acid-containing composition 10 in water in a state where it disappears visually or disappears substantially leaving only a slight precipitate. Therefore, since there is almost no need to remove insoluble matter, the convenience of the resin acid eluate 20 (see FIG. 2) obtained by eluting the resin acid-containing composition 10 in water is improved. The water, which is the solvent in which the resin acid-containing composition 10 should be eluted, is, for example, tap water, ion-exchanged water, distilled water, or the like.

[0017] In this specification, "elution" refers to a state in which, upon visual observation, it is transparent or substantially transparent, and by ultraviolet spectrophotometry, a mixed solution (solution or dispersion) is formed in which the presence of solutes (here, resin acids and water-soluble organic matrices) in a solvent (here, water) is confirmed.

[0018] The form of the resin acid-containing composition 10 is not particularly limited. The resin acid-containing composition 10 may be a solid (for example, a solid or a gel), or may be a fluid (for example, a liquid or a sol).

[0019] When the resin acid-containing composition 10 is a solid, the shape of the resin acid-containing composition 10 can be appropriately changed according to the intended use and the like. The resin acid-containing composition 10 may have a shape with a relatively large specific surface area. Examples of such shapes include film-like, fibrous, and granular shapes. According to such a configuration, when the resin acid-containing composition 10 is immersed in water, the contact area with water becomes large, so that the resin acid-containing composition 10 can be easily eluted into water rapidly. Among these shapes, since the resin acid-containing composition 10 can be easily obtained by the production method described later, it is preferable that the resin acid-containing composition 10 has a film-like shape.

[0020] However, the resin acid-containing composition 10 may have a shape with a relatively small specific surface area. Examples of such shapes include block-like shapes. According to such a configuration, since the resin acid-containing composition 10 is easy to grasp, the resin acid-containing composition 10 is easy to handle.

[0021] When the resin acid-containing composition 10 is a fluid, the water-soluble organic matrix 11 may be a fluid. According to such a configuration, the resin acid-containing composition 10 is more easily eluted by water, which is the same fluid. The resin acid-containing composition 10 may be a concept including a resin acid eluate 20 (see FIG. 2) obtained by eluting a resin acid-containing composition 10, which is a solid, into water, as described later.

[0022] Hereinafter, each element constituting the resin acid-containing composition 10 of the present embodiment will be described.

[0023] [Water-soluble organic matrix] The water-soluble organic matrix 11 is a matrix having solubility in water. Here, in this specification, "having solubility in water" means that, for example, a solute to be dissolved in water dissolves 1 g or more, specifically 2 g or more, more specifically 5 g or more in 100 mL of distilled water at a temperature of 20 ± 5°C.

[0024] The material constituting the water-soluble organic matrix 11 is not particularly limited as long as it is an organic material having solubility in water that satisfies the above conditions. The water-soluble organic matrix 11 may contain, for example, a water-soluble cellulose derivative, or may be composed only of a water-soluble cellulose derivative. Examples of the water-soluble cellulose derivative include water-soluble alkyl cellulose, water-soluble hydroxyalkyl cellulose, water-soluble carboxy cellulose, water-soluble cellulose acetate, etc. Examples of the water-soluble alkyl cellulose include methyl cellulose, ethyl cellulose, etc. Examples of the water-soluble hydroxyalkyl cellulose include hydroxymethyl cellulose, hydroxyethyl methyl cellulose, hydroxypropyl cellulose, hydroxypropyl methyl cellulose, hydroxypropyl ethyl cellulose, etc. Examples of the water-soluble carboxy cellulose include celluronic acid, carboxymethyl cellulose, carboxymethyl ethyl cellulose, etc. Examples of the water-soluble cellulose acetate include cellulose acetate in which the number of hydroxyl groups substituted with acetyl groups is 0.4 to 0.9 among the three hydroxyl groups of the glucose ring. The water-soluble organic matrix 11 may contain at least one selected from the group consisting of the above water-soluble cellulose derivatives, or may be composed only of at least one selected from the group consisting of the above water-soluble cellulose derivatives.

[0025] The water-soluble organic matrix 11 preferably contains a water-soluble cellulose derivative that is approved as a food additive. According to such a configuration, the safety of the resin acid-containing composition 10 can be enhanced. Examples of such water-soluble cellulose derivatives include methyl cellulose, hydroxypropyl methyl cellulose, carboxymethyl cellulose, and the like. Therefore, the water-soluble organic matrix 11 preferably contains at least one selected from the group consisting of the above water-soluble cellulose derivatives, and more preferably consists of only at least one selected from the group consisting of the above water-soluble cellulose derivatives.

[0026] The water-soluble organic matrix 11 preferably contains methyl cellulose. According to such a configuration, when the resin acid-containing composition 10 is eluted in water, the elution rate of the resin acid 12 (particularly abietic acid) can be increased, and a stable elution state of the resin acid 12 (particularly abietic acid) over a long period can be ensured.

[0027] In addition, in this specification, the "water-soluble cellulose derivative" is a concept that includes not only the water-soluble cellulose derivative itself but also salts of the water-soluble cellulose derivative. For example, the expression "carboxymethyl cellulose" is an expression that includes not only carboxymethyl cellulose itself but also carboxymethyl cellulose salts. When the water-soluble cellulose derivative is a water-soluble cellulose derivative salt, examples of the ions constituting the salt include monovalent cations of metals such as Li, Na, and K, divalent cations of metals such as Be, Mg, and Ca, and trivalent cations of metals such as B and Al. The ions constituting the water-soluble cellulose derivative salt may contain at least one selected from the group consisting of the above metal ions, or may consist of only at least one selected from the group consisting of the above metal ions.

[0028] The ions constituting the water-soluble cellulose derivative salt preferably include metal ions selected from the group consisting of Na, K, and Mg, and more preferably include Na ions. According to such a configuration, the water-soluble cellulose derivative salt easily dissolves in water. The ions constituting the water-soluble cellulose derivative salt may be composed only of metal ions selected from the group consisting of Na, K, and Mg, or may be composed only of Na ions.

[0029] If the resin acid-containing composition 10 includes the water-soluble organic matrix 11 as a matrix, it may contain components of other matrices that do not have solubility in water (hereinafter referred to as "water-insoluble matrices"). The resin acid-containing composition 10 preferably contains the water-soluble organic matrix 11 as a main component. According to such a configuration, when the resin acid-containing composition 10 is eluted in water, insolubles can be further suppressed. In the present specification, the "main component" means a component that is contained in the largest amount by weight in a certain substance (here, the matrix), or a component that is contained in a certain substance at 30% by weight or more, specifically 40% by weight or more. In the matrix, the water-soluble organic matrix 11 and the water-insoluble matrix may be integrated by mixing their components, or may form separate matrices, for example, as separate layers.

[0030] The components of the water-insoluble matrix are not particularly limited as long as they do not inhibit the solubility of the components of the water-soluble cellulose derivative in water. The water-insoluble matrix is, for example, an organic matrix that does not have solubility in water (hereinafter referred to as "water-insoluble organic matrix"). The water-insoluble organic matrix may contain cellulose derivatives that do not have solubility in water (hereinafter referred to as "water-insoluble celluloses") among celluloses that are components of the same type as the water-soluble organic matrix 11, or may be composed only of water-insoluble celluloses.

[0031] Examples of water-insoluble celluloses include cellulose nanofibers, cellulose microfibrils, cellulose nanocrystals, bacterial nanocellulose, etc. The cellulose nanofibers are not particularly limited. Examples of the cellulose nanofibers include TEMPO-oxidized cellulose nanofibers, phosphate-esterified cellulose nanofibers, mechanically defibrated cellulose nanofibers, partially deacetylated cellulose nanofibers, carboxymethylated cellulose nanofibers, xanthated cellulose nanofibers, phosphite-esterified cellulose nanofibers, sulfate-esterified cellulose nanofibers, endo-type cellulase-treated cellulose nanofibers, etc. The component of the water-insoluble matrix may contain at least one selected from the group consisting of the above water-insoluble celluloses, or may be composed of only at least one selected from the group consisting of the above water-insoluble celluloses.

[0032] [Resin acid] Resin acid 12 is a natural resin extracted from natural tree species. Examples of resin acid 12 include abietic acid contained in rosin, which is the non-volatile component of pine resin. Rosin is generally classified into any one of three types: gum rosin, wood rosin, or tall oil rosin, depending on the manufacturing method. Rosin contains abietic acids such as abietic acid, neoabietic acid, dehydroabietic acid, pimaric acid, levopimaric acid, isopimaric acid, and palustric acid. In this specification, when it is said that "containing resin acid", the resin acid naturally includes rosin itself such as gum rosin, wood rosin, and tall oil rosin.

[0033] In addition, in this specification, "resin acid" is a concept that includes not only the resin acid itself but also salts of the resin acid. For example, the expression "abietic acid" includes not only abietic acid itself but also expressions including abietate. When the resin acid is a resin acid salt, examples of the ions constituting the salt include monovalent cations of metals such as Na, K, and Ag, and divalent cations of metals such as Ca, Ba, and Zn. The ions constituting the resin acid salt may contain at least one selected from the group consisting of the above metal ions, or may be composed of only at least one selected from the group consisting of the above metal ions.

[0034] The ions constituting the resin acid salt may contain at least one metal ion of Na and K. According to such a configuration, the resin acid is stabilized. The ions constituting the water-soluble cellulose derivative salt may be composed of only at least one metal ion of Na and K.

[0035] Resin acid 12 contains, for example, at least one selected from the group consisting of the above resin acids contained in rosin, or is composed of only at least one selected from the group consisting of the above resin acids. Resin acid 12 preferably contains abietic acid, which is the main component of rosin. Resin acid 12 may be composed of only abietic acid.

[0036] The weight ratio of the resin acid 12 to the water-soluble organic matrix 11 is not particularly limited. The weight ratio of the resin acid to the water-soluble organic matrix is represented by (relative weight of resin acid) / (relative weight of water-soluble organic matrix), with the weight of the resin acid-containing composition being 100. The weight ratio of the resin acid 12 to the water-soluble organic matrix 11 is, for example, 1 / 99 or more, 2 / 98 or more, 3 / 97 or more, 4 / 96 or more, and in some cases, it may be 5 / 95 or more, 6 / 94 or more, 7 / 93 or more, or 8 / 92 or more, 9 / 91 or more. The weight ratio of the resin acid 12 to the water-soluble organic matrix 11 is, for example, 50 / 50 or less, 40 / 60 or less, 35 / 65 or less, 30 / 70 or less, and in some cases, it may be 25 / 75 or less, 20 / 80 or less, 15 / 85 or less, or even 14 / 86 or less, 13 / 87 or less, 12 / 88 or less, 11 / 89.

[0037] The weight ratio of the resin acid 12 to the water-soluble organic matrix 11 is preferably, for example, 1 / 99 or more and 50 / 50 or less, 1 / 99 or more and 45 / 55 or less, more preferably 1 / 99 or more and 40 / 60 or less, 1 / 99 or more and 35 / 65 or less, and even more preferably 5 / 95 or more and 35 / 65 or less, 8 / 92 or more and 32 / 68 or less. With such a configuration, when the water-soluble organic matrix 11 is eluted in water, insolubles are more easily suppressed.

[0038] In addition, when the resin acid-containing composition 10 contains a water-insoluble matrix, the weight ratio of the resin acid 12 to the total weight of the water-soluble organic matrix 11 and the water-insoluble matrix ((relative weight of resin acid) / (relative total weight of water-soluble organic matrix and water-insoluble matrix), with the weight of the resin acid-containing composition being 100) may also be within the above weight ratio range.

[0039] Figure 2 schematically shows a resin acid eluate 20 obtained by eluting the resin-containing composition 10 (see Figure 1) of the present embodiment in distilled water 13 in a container 30. Hereinafter, the elution characteristics of the resin acid-containing composition 10 of the present embodiment in distilled water 13 will be described. In Figure 2, the water-soluble organic matrix 11 and the resin acid 12 eluted in the resin acid eluate 20 are depicted in a visualized manner. However, in reality, the resin acid eluate 20 is transparent or in a substantially transparent state. Therefore, in the state of the resin acid eluate 20, the water-soluble organic matrix 11 and the resin acid 12 cannot be visually recognized or can only be visually recognized as slight precipitates.

[0040] [Measurement of the dissolution rate of the resin acid-containing composition in distilled water] The dissolution rate of the resin acid 12 contained in the resin acid-containing composition 10 of the present embodiment in distilled water 13 can be measured using the supernatant separated from the resin acid eluate 20 by centrifugation immediately after preparing a resin acid eluate 20 by eluting at least a part of the resin acid 12 in distilled water 13 by shaking for a predetermined time at a temperature of 37.0 ± 0.5 °C with respect to the distilled water 13 (hereinafter referred to as "resin acid immersion water") in which the resin acid-containing composition 10 is immersed.

[0041] Specifically, the dissolution rate of the resin acid 12 contained in the resin acid-containing composition 10 in distilled water 13 can be measured as follows. First, the resin acid-containing composition 10 is immersed in distilled water 13 to prepare resin acid immersion water. Next, under the conditions of a temperature of 37.0 ± 0.5 °C, a turning speed of 1000 rpm, and a turning radius of 1.5 mm, the resin acid immersion water is continuously shaken for a predetermined time (specifically, as described later, 30 minutes, 8 hours, 3 days, 28 days). By this shaking, a resin acid eluate 20 is prepared by eluting at least a part of the resin acid-containing composition 10 in distilled water 13. Immediately after the preparation by shaking is completed, the resin acid eluate 20 is centrifuged under the conditions of room temperature (15 °C to 30 °C) and a rotation speed of 5000 rpm (relative centrifugal acceleration: 15770 × g) to obtain a supernatant and a precipitate.

[0042] Thereafter, the concentration of resin acid 12 in the supernatant liquid is measured. The method for measuring the concentration of resin acid 12 in the supernatant liquid is not particularly limited. The measurement method is preferably an absorptiometry. According to such a configuration, the concentration of resin acid 12 in the supernatant liquid can be measured relatively easily. When using absorptiometry, light in a predetermined wavelength range is irradiated onto the supernatant liquid, and the concentration of resin acid 12 in the supernatant liquid is measured from the absorbance of the light of the supernatant liquid. The absorptiometry is preferably an ultraviolet absorptiometry using light in the ultraviolet wavelength range. According to such a configuration, since the supernatant liquid in which resin acid 12 has eluted exhibits a high absorbance to ultraviolet rays, it becomes easier to measure the concentration of resin acid 12 in the supernatant liquid.

[0043] Finally, the elution rate of resin acid 12 in the resin acid-containing composition 10 into distilled water 13 is calculated by calculating the weight of resin acid 12 eluted in the supernatant liquid from the concentration of resin acid 12 in the supernatant liquid.

[0044] In this specification, the elution rate of resin acid into distilled water is calculated from the following formula. Elution rate of resin acid (%) = (Weight of resin acid eluted in the supernatant liquid) / (Weight of resin acid in the resin acid-containing composition immersed in distilled water) × 100

[0045] Hereinafter, for convenience of explanation, "the elution rate of resin acid into distilled water obtained by measuring using the supernatant liquid separated from the resin acid eluate prepared by eluting at least a part of the resin acid into distilled water by shaking for T hours at a temperature of 37.0 ± 0.5 °C with respect to the resin acid immersion water obtained by immersing the resin acid-containing composition in distilled water immediately after preparation" is simply referred to as "the elution rate of resin acid after T hours".

[0046] [Elution rate of resin acid after 30 minutes] In the resin acid-containing composition 10 of the present embodiment, the elution rate of the resin acid 12 after 30 minutes is 20.0% by weight or more. The elution rate of the resin acid 12 after 30 minutes may be 30.0% by weight or more, 40.0% by weight or more, 50.0% by weight or more, and in some cases, may be 60.0% by weight or more, 65.0% by weight or more, 70.0% by weight or more, and further may be 75.0% by weight or more, 80.0% by weight or more, 85.0% by weight or more, 90.0% by weight or more. The elution rate of the resin acid 12 after 30 minutes is, for example, 95.0% by weight or less, 90.0% by weight or less, 85.0% by weight or less, and in some cases, may be 80.0% by weight or less, 75.0% by weight or less, 70.0% by weight or less, and further may be 65.0% by weight or less, 60.0% by weight or less, 55.0% by weight or less, 50.0% by weight or less.

[0047] Thus, in the resin acid-containing composition 10 of the present embodiment, the resin acid 12 elutes into the distilled water 13 at a high elution rate of 20.0% by weight or more by shaking for 30 minutes. From the viewpoint of the effective utilization of the resin acid 12 in the elution state into the distilled water 13, the elution rate of the resin acid 12 after 30 minutes is preferably 40.0% by weight or more, more preferably 60.0% by weight or more, further preferably 70.0% by weight or more, and even more preferably 80.0% by weight or more.

[0048] [Elution rate of resin acid after 8 hours] In the resin acid-containing composition 10 of the present embodiment, the elution rate of the resin acid 12 after 8 hours can be appropriately changed according to the elution characteristics of the resin acid 12 required for the use of the resin acid-containing composition 10. The elution rate of the resin acid 12 after 8 hours is, for example, 20.0% by weight or more, 25.0% by weight or more, 30.0% by weight or more, and in some cases, it may be 35.0% by weight or more, 40.0% by weight or more, 45.0% by weight or more, and further, it may be 50.0% by weight or more, 55.0% by weight or more, 60.0% by weight or more, 65.0% by weight or more. The elution rate of the resin acid 12 after 8 hours is, for example, 95.0% by weight or less, 90.0% by weight or less, 85.0% by weight or less, and in some cases, it may be 80.0% by weight or less, 75.0% by weight or less, 70.0% by weight or less, and further, it may be 65.0% by weight or less, 60.0% by weight or less, 55.0% by weight or less, 50.0% by weight or less.

[0049] Even by shaking for 8 hours, if a high elution rate of the resin acid 12 can be maintained, it can be said that the resin acid 12 is less likely to aggregate due to external stress such as impact, and it is a stable elution state. From the viewpoint of ensuring a stable elution state of the resin acid 12, the elution rate of the resin acid 12 after 8 hours is preferably 30.0% by weight or more, more preferably 40.0% by weight or more, still more preferably 50.0% by weight or more, and even more preferably 60.0% by weight or more.

[0050] Incidentally, the elution rate of the resin acid 12 after 8 hours may significantly decrease compared to the elution rate of the resin acid 12 after 30 minutes. The resin acid-containing composition 10 having such elution characteristics of the resin acid 12 into the distilled water 13 can be used when, for example, a non-woven fabric (e.g., a cellulose-based non-woven fabric) is to be stored in a wet state with the resin acid eluate 20 and the resin acid 12 is to be fixed to the non-woven fabric during storage of the non-woven fabric. The sheet with the resin acid 12 fixed thereto can be used, for example, as an antibacterial sheet for the kitchen, an antibacterial sheet for the toilet, etc. When assuming such a usage form of the resin acid-containing composition 10, it is preferable that the elution rate of the resin acid 12 after 8 hours is half or less of the elution rate of the resin acid 12 after 30 minutes. In this case, the elution rate of the resin acid 12 after 8 hours may be below the lower limit value of the elution rate exemplified above.

[0051] [Elution rate of resin acid after 3 days] In the resin acid-containing composition 10 of the present embodiment, the elution rate of the resin acid 12 after 3 days can be appropriately changed according to the elution characteristics of the resin acid 12 required for the usage of the resin acid-containing composition 10. The elution rate of the resin acid 12 after 3 days is, for example, 15.0% by weight or more, 20.0% by weight or more, 25.0% by weight or more, and in some cases, may be 30.0% by weight or more, 35.0% by weight or more, 40.0% by weight or more, and further may be 45.0% by weight or more, 50.0% by weight or more. The elution rate of the resin acid 12 after 3 days is, for example, 95.0% by weight or less, 90.0% by weight or less, 85.0% by weight or less, and in some cases, may be 80.0% by weight or less, 75.0% by weight or less, 70.0% by weight or less, and further may be 65.0% by weight or less, 60.0% by weight or less, 55.0% by weight or less, 50.0% by weight or less.

[0052] If a high elution rate of the resin acid 12 can be maintained even by shaking for 3 days, it can be said that the aggregation of the resin acid 12 is less likely to occur due to external stress and the elution state is more stable. From the viewpoint of ensuring a stable elution state of the resin acid 12, the elution rate of the resin acid 12 after 3 days is preferably 20.0% by weight or more, more preferably 30.0% by weight or more, and even more preferably 40.0% by weight or more.

[0053] [Elution rate of resin acid after 28 days] In the resin acid-containing composition 10 of the present embodiment, the elution rate of the resin acid 12 after 28 days can be appropriately changed according to the elution characteristics of the resin acid 12 required for the use of the resin acid-containing composition 10. The elution rate of the resin acid 12 after 28 days is, for example, 15.0% by weight or more, 20.0% by weight or more, 25.0% by weight or more, and in some cases, may be 30.0% by weight or more, 35.0% by weight or more, 40.0% by weight or more, and further may be 45.0% by weight or more, 50.0% by weight or more. The elution rate of the resin acid 12 after 28 days is, for example, 95.0% by weight or less, 90.0% by weight or less, 85.0% by weight or less, and in some cases, may be 80.0% by weight or less, 75.0% by weight or less, 70.0% by weight or less, and further may be 65.0% by weight or less, 60.0% by weight or less, 55.0% by weight or less, 50.0% by weight or less.

[0054] Even by shaking for 28 days, if a high elution rate of the resin acid 12 can be maintained, it can be said that the aggregation of the resin acid 12 is less likely to occur due to external stress, and the elution state is more stable. From the viewpoint of ensuring a stable elution state of the resin acid 12, the elution rate of the resin acid 12 after 28 days is preferably 20.0% by weight or more, more preferably 30.0% by weight or more, and even more preferably 40.0% by weight or more.

[0055] According to the resin acid-containing composition 10 of the present embodiment, as described above, when the resin acid-containing composition 10 is eluted in water, a resin acid eluate 20 in which the resin acid 12 is eluted at a high elution rate and the insolubles are suppressed can be obtained. Therefore, when using the resin acid eluate 20, there is almost no need to remove insolubles, so the convenience of the resin acid eluate 20 is improved. Therefore, the resin acid-containing composition 10 of the present embodiment is suitable for use by supply methods such as spraying, coating, and dropping after eluting in water to prepare the resin acid eluate 20.

[0056] Since the resin acid-containing composition 10 of the present embodiment has antibacterial and antiviral properties as described later, it is expected to be applied to bactericides even in a solid state (for example, a film state). Further, since the resin acid-containing composition 10 of the present embodiment has solubility in water, it is also expected to be applied to water-soluble coating agents, water-soluble adhesives, and the like. Furthermore, the resin acid-containing composition 10 of the present embodiment is expected to be applied to antibiotics by combining with at least one of methylcellulose and hydroxypropylcellulose included in the Japanese Pharmacopoeia.

[0057] <Method for producing resin acid-containing composition> FIG. 3 shows a method for producing the resin acid-containing composition 10 (see FIG. 1) of the present embodiment. Note that since the matters described for the resin acid-containing composition 10 of the present embodiment can be applied to the following production method, duplicate explanations may be omitted. Further, the matters described in the following production method of the present embodiment can be applied to the resin acid-containing composition 10 of the present embodiment. Hereinafter, with reference to FIG. 3, the method for producing the resin acid-containing composition 10 of the present embodiment will be described.

[0058] First, in step S1 shown in FIG. 3, a resin acid-containing liquid containing resin acid 12 (see FIG. 1) and an organic solvent is prepared. The organic solvent is not particularly limited as long as it can elute resin acid 12. In step S1, the resin acid-containing liquid is prepared so that at least a part of resin acid 12 elutes into the organic solvent. It is preferable that all of resin acid 12 has eluted into the organic solvent. The organic solvent may be a polar organic solvent or a nonpolar organic solvent. Examples of the organic solvent include ketones, ethers, halogenated alkyls, and aromatic compounds. Examples of the ketones include acetone and methyl ethyl ketone. Examples of the ethers include dioxane, diethyl ether, and tetrahydrofuran. Examples of the halogenated alkyls include halogenated alkyls such as chloroform and carbon tetrachloride. Examples of the aromatic hydrocarbons include benzene and toluene.

[0059] The organic solvent used in the preparation of the resin acid-containing liquid may be composed of at least one selected from the group consisting of the above organic solvents. The organic solvent is preferably a polar organic solvent. According to such a configuration, the organic solvent can be easily mixed with water. The organic solvent is more preferably composed of at least one selected from the group consisting of acetone and tetrahydrofuran. According to such a configuration, the organic solvent can be more easily mixed with water. The organic solvent is even more preferably composed of acetone. According to such a configuration, in the resin acid eluate 20 (see FIG. 2) obtained by eluting the resin acid-containing composition 10 (see FIG. 1) produced by the production method of the present embodiment in water, the elution rate of the resin acid 12 (see FIG. 2) into water is likely to be improved.

[0060] Next, in step S2 shown in FIG. 3, a mixed liquid containing the resin acid 12 (see FIG. 1), the organic solvent, the water-soluble organic matrix 11 (see FIG. 1), and water is prepared using the resin acid-containing liquid. In step S2, for example, the mixed liquid is prepared by separately adding the water-soluble organic matrix 11 and water to the resin acid-containing liquid prepared in step S1. When preparing the mixed liquid, the mixed liquid is prepared so that at least a part of the water-soluble organic matrix 11 elutes into the mixed liquid. It is preferable that all of the water-soluble organic matrix 11 has eluted into the mixed liquid. According to such a configuration, in the resin acid-containing composition 10 (see FIG. 1), the resin acid 12 is likely to be dispersed in the water-soluble organic matrix 11. The water is preferably distilled water. According to such a configuration, the amount of impurities in the resin acid-containing composition 10 can be reduced.

[0061] In step S2, separately from the resin acid-containing liquid prepared in step S1, an organic matrix-containing liquid containing the water-soluble organic matrix 11 (see FIG. 1) and water may be prepared, and the mixed liquid may be prepared by mixing the resin acid-containing liquid and the organic matrix-containing liquid. When preparing the organic matrix-containing liquid, the organic matrix-containing liquid is prepared so that at least a part of the water-soluble organic matrix 11 elutes into water. It is preferable that all of the water-soluble organic matrix 11 has eluted into water. The water is preferably distilled water.

[0062] In the preparation of the resin acid-containing liquid, a treatment for promoting the elution of resin acid 12 (see FIG. 1) into an organic solvent may be performed. Examples of the treatment for promoting the elution of resin acid 12 into an organic solvent include shaking, stirring, heating, and ultrasonic treatment. One or more treatments selected from these treatments can be used as a treatment for promoting the elution of resin acid 12 into an organic solvent. Further, in the preparation of the organic matrix-containing liquid, a treatment for promoting the elution of the water-soluble organic matrix 11 (see FIG. 1) into water may be performed in the same manner as the above treatment. Furthermore, in the preparation of the mixed liquid, a treatment for promoting the elution of resin acid 12 and the water-soluble organic matrix 11 into an organic solvent and water may be performed in the same manner as the above treatment.

[0063] Next, in step S3 shown in FIG. 3, at least a part of the organic solvent is removed from the mixed liquid. Thereby, the resin acid-containing composition 10 containing resin acid 12 and the water-soluble organic matrix 11 shown in FIG. 1 is obtained. Specifically, the organic solvent contained in the mixed liquid can be removed by volatilization. All of the organic solvent may be removed. Furthermore, at least a part of the water contained in the mixed liquid may also be removed. Specifically, the water contained in the mixed liquid can be removed by drying in a low-humidity environment. All of the water may be removed. When removing both the organic solvent and water, the organic solvent may be volatilized and the water may be evaporated by heating the mixed liquid.

[0064] According to the method for producing the resin acid-containing composition 10 of the present embodiment, when eluted in water, a resin acid-containing composition 10 capable of eluting resin acid 12 at a high elution rate and suppressing insolubles can be produced.

Examples

[0065] Hereinafter, the details of the present invention will be described using examples and comparative examples. Note that the resin acid-containing composition, the antibacterial agent, and the method for producing the resin acid-containing composition of the present invention are not limited to the following examples.

[0066] To evaluate the elution rate of the resin acids in the resin acid-containing composition, samples of Examples 1 to 13 and Comparative Examples 1 to 4 were prepared as follows.

[0067] <Example 1> An 18 g aqueous solution containing 0.25 wt% methyl cellulose (manufactured by Nacalai Tesque, Inc.) and a 1 g acetone solution containing 0.5 wt% abietic acid (manufactured by Nacalai Tesque, Inc.) were mixed to prepare a mixed solution. The prepared mixed solution was subjected to ultrasonic treatment twice using an ultrasonic homogenizer (product name "US-150E" manufactured by Nippon Seiki Co., Ltd.). Next, 80 μL of the mixed solution was dropped onto a Teflon (registered trademark) petri dish and dried in air at room temperature for 4 hours. Thereby, a film-like solid sample of a resin acid-containing composition having a weight ratio of abietic acid to methyl cellulose of 10 / 90 was obtained.

[0068] <Example 2> An 18 g aqueous solution containing 0.25 wt% hydroxypropyl methyl cellulose (manufactured by Santa Cruz Biotechnology) and a 1 g acetone solution containing 0.5 wt% abietic acid (manufactured by Nacalai Tesque, Inc.) were mixed to prepare a mixed solution. The prepared mixed solution was subjected to ultrasonic treatment and drying treatment in the same manner as in Example 1. Thereby, a film-like solid sample of a resin acid-containing composition having a weight ratio of abietic acid to hydroxypropyl methyl cellulose of 10 / 90 was obtained.

[0069] <Example 3> An 18 g aqueous solution containing 0.25 wt% carboxymethyl cellulose (sodium salt) (manufactured by Nacalai Tesque, Inc.) and a 1 g acetone solution containing 0.5 wt% abietic acid (manufactured by Nacalai Tesque, Inc.) were mixed to prepare a mixed solution. The prepared mixed solution was subjected to ultrasonic treatment and drying treatment in the same manner as in Example 1. Thereby, a film-like solid sample of a resin acid-containing composition having a weight ratio of abietic acid to carboxymethyl cellulose (sodium salt) of 10 / 90 was obtained.

[0070] <Example 4> An 18 g aqueous solution containing 0.25 wt% methyl cellulose (manufactured by Nacalai Tesque, Inc.) and a 1 g acetone solution containing 0.5 wt% rosin (product name “Rogin, Gum” manufactured by Acros Organics) were mixed to prepare a mixed solution. Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-shaped solid sample of a resin acid-containing composition with a weight ratio of rosin to methyl cellulose of 10 / 90 was obtained.

[0071] <Example 5> An 18 g aqueous solution containing 0.25 wt% hydroxypropylmethyl cellulose (manufactured by Santa Cruz Biotechnology) and a 1 g acetone solution containing 0.5 wt% rosin (product name “Rogin, Gum” manufactured by Acros Organics) were mixed to prepare a mixed solution. Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-shaped solid sample of a resin acid-containing composition with a weight ratio of rosin to hydroxypropylmethyl cellulose of 10 / 90 was obtained.

[0072] <Example 6> An 18 g aqueous solution containing 0.25 wt% hydroxypropylmethyl cellulose (manufactured by Santa Cruz Biotechnology) and a 1 g tetrahydrofuran solution containing 0.5 wt% rosin (product name “Rogin, Gum” manufactured by Acros Organics) were mixed to prepare a mixed solution. Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-shaped solid sample of a resin acid-containing composition with a weight ratio of rosin to hydroxypropylmethyl cellulose of 10 / 90 was obtained.

[0073] <Example 7> An aqueous solution of 18 g containing 0.25 wt% of carboxymethyl cellulose (sodium salt) (manufactured by Nacalai Tesque, Inc.) and an acetone solution of 1 g containing 0.5 wt% of rosin (product name "Rogin, Gum" manufactured by Acros Organics) were mixed to prepare a mixed solution. Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-like solid sample of a resin acid-containing composition with a weight ratio of abietic acid to carboxymethyl cellulose (sodium salt) of 10 / 90 was obtained.

[0074] <Example 8> An aqueous solution of 9 g containing 0.25 wt% of methyl cellulose (manufactured by Nacalai Tesque, Inc.), an aqueous solution of 9 g containing 0.25 wt% of hydroxypropyl methyl cellulose (manufactured by Santa Cruz Biotechnology), and an acetone solution of 1 g containing 0.5 wt% of abietic acid (manufactured by Nacalai Tesque, Inc.) were mixed to prepare a mixed solution. Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-like solid sample of a resin acid-containing composition with a weight ratio of abietic acid to methyl cellulose and hydroxypropyl methyl cellulose of 10 / (45 + 45) was obtained.

[0075] <Example 9> An aqueous solution of 9 g containing 0.25 wt% of methyl cellulose (manufactured by Nacalai Tesque, Inc.), an aqueous solution of 9 g containing 0.25 wt% of carboxymethyl cellulose (sodium salt) (manufactured by Nacalai Tesque, Inc.), and an acetone solution of 1 g containing 0.5 wt% of abietic acid (manufactured by Nacalai Tesque, Inc.) were mixed to prepare a mixed solution. Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-like solid sample of a resin acid-containing composition with a weight ratio of abietic acid to methyl cellulose and carboxymethyl cellulose (sodium salt) of 10 / (45 + 45) was obtained.

[0076] <Example 10> A mixed solution was prepared by mixing 16 g of an aqueous solution containing 0.25% by weight of methyl cellulose (manufactured by Nacalai Tesque, Inc.) and 2 g of an acetone solution containing 0.5% by weight of abietic acid (manufactured by Nacalai Tesque, Inc.). Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-shaped solid sample of a resin acid-containing composition with a weight ratio of abietic acid to methyl cellulose of 20 / 80 was obtained.

[0077] <Example 11> A mixed solution was prepared by mixing 14 g of an aqueous solution containing 0.25% by weight of methyl cellulose (manufactured by Nacalai Tesque, Inc.) and 3 g of an acetone solution containing 0.5% by weight of abietic acid (manufactured by Nacalai Tesque, Inc.). Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-shaped solid sample of a resin acid-containing composition with a weight ratio of abietic acid to methyl cellulose of 30 / 70 was obtained.

[0078] <Example 12> A mixed solution was prepared by mixing 12 g of an aqueous solution containing 0.25% by weight of methyl cellulose (manufactured by Nacalai Tesque, Inc.) and 4 g of an acetone solution containing 0.5% by weight of abietic acid (manufactured by Nacalai Tesque, Inc.). Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-shaped solid sample of a resin acid-containing composition with a weight ratio of abietic acid to methyl cellulose of 40 / 60 was obtained.

[0079] <Example 13> A mixed solution was prepared by mixing 9 g of an aqueous solution containing 0.25 wt% of methyl cellulose (manufactured by Nacalai Tesque, Inc.), 9 g of an aqueous dispersion containing 0.25 wt% of TEMPO-oxidized cellulose nanofibers (product name "Reocrista I-2SX" manufactured by Daiichi Kogyo Seiyaku Co., Ltd.), and 1 g of an acetone solution containing 0.5 wt% of abietic acid (manufactured by Nacalai Tesque, Inc.). Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-shaped solid sample of a resin acid-containing composition with a weight ratio of abietic acid to methyl cellulose and TEMPO-oxidized cellulose nanofibers of 10 / (45 + 45) was obtained.

[0080] <Comparative Example 1> Without using celluloses as the matrix, only a powdery solid sample of abietic acid (manufactured by Nacalai Tesque, Inc.) was prepared.

[0081] <Comparative Example 2> Without using celluloses as the matrix, only a powdery solid sample of rosin (product name "Rogin, Gum" manufactured by Acros Organics) was prepared.

[0082] <Comparative Example 3> A mixed solution was prepared by mixing 18 g of an aqueous dispersion containing 0.25 wt% of cellulose nanofibers (product name "BinFis WFo-10002" manufactured by Sugino Machine, Ltd.) and 1 g of an acetone solution containing 0.5 wt% of abietic acid (manufactured by Nacalai Tesque, Inc.). Ultrasonic treatment and drying treatment were performed on the prepared mixed solution in the same manner as in Example 1. As a result, a film-shaped solid sample of a resin acid-containing composition with a weight ratio of abietic acid to cellulose nanofibers of 10 / 90 was obtained.

[0083] <Comparative Example 4> 18 g of an aqueous dispersion containing 0.25% by weight of TEMPO-oxidized cellulose nanofibers (product name "Reocrista I-2SX" manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and 1 g of an acetone solution containing 0.5% by weight of abietic acid (manufactured by Nacalai Tesque, Inc.) were mixed to prepare a mixed solution. The prepared mixed solution was subjected to ultrasonic treatment and drying treatment in the same manner as in Example 1. As a result, a solid sample of a film-like resin acid-containing composition having a weight ratio of abietic acid to TEMPO-oxidized cellulose nanofibers of 10 / 90 was obtained.

[0084] [Measurement of Elution Rate of Resin Acid] For the samples of Examples 1 to 13 and Comparative Examples 1 to 4, the elution rate of resin acid was measured by the following method.

[0085] [Measurement of Elution Rate of Resin Acid in Example 1] Thirty film-like solid samples of Example 1 (6.0 mg to 7.0 mg in terms of weight) and 1.5 mL of distilled water were placed in a microtube. Using a thermo-hygrostat (product name "DWMax MBR-032P" manufactured by Taitec Co., Ltd.), the microtube was swirled and shaken under the conditions of a temperature of 37.0 ± 0.5 °C, a swirling speed of 1000 rpm, a swirling radius of 1.5 mm, and four shaking times of 30 minutes, 8 hours, 3 days, and 28 days to prepare a resin acid eluate. Five resin acid eluates were prepared for each of the four shaking times.

[0086] After shaking for 30 minutes, 8 hours, 3 days, and 28 days, using a centrifuge (product name "HSIANGTAI CENTRFUGE CN-206" manufactured by AS ONE Corporation), at room temperature (15°C to 30°C) and a rotation speed of 5000 rpm (relative centrifugal acceleration: 15770×g), each resin acid eluate was centrifuged for 5 minutes. Among the supernatant liquids separated by centrifugation, 40 μL was extracted, and 160 μL of isopropanol was added to the extracted supernatant liquid and mixed. Then, using a microreader (product name "Spark" manufactured by Tecan Japan Co., Ltd.), the mixture was irradiated with ultraviolet light, and the absorbance at 240 nm, which is the maximum absorption wavelength of abietic acid in isopropanol, was measured. From the absorbance measured for each mixture, the concentration of abietic acid eluted in the supernatant liquid was calculated, and from the calculated concentration of abietic acid, the weight of abietic acid eluted in the supernatant liquid was calculated. Thereafter, as described above, from the weight ratio of abietic acid eluted in the supernatant liquid to abietic acid (abietic acid in 30 solid samples) in the resin acid-containing composition immersed in distilled water, the elution rate of abietic acid corresponding to each resin acid eluate was calculated. The elution rate of abietic acid into distilled water at each shaking time was taken as the average value of the elution rates of abietic acid in the five resin acid eluates prepared for that shaking time.

[0087] <Measurement of the Elution Rate of Resin Acids in Examples 2 to 13 and Comparative Examples 3 to 4> In the same manner as in Example 1, 30 film-shaped solid samples (6.0 mg to 7.0 mg in terms of weight) and 1.5 mL of distilled water were placed in a microtube, and a resin acid eluate was prepared under the same shaking conditions as in Example 1. Thereafter, in the same manner as in Example 1, the amount of abietic acid eluted into distilled water was calculated from the measurement results of the concentration of abietic acid in the supernatant liquid of the resin acid eluate by ultraviolet spectrophotometry.

[0088] <Measurement of the Elution Rate of Resin Acids in Comparative Examples 1 to 2> Samples of 1.0 mg to 2.0 mg (in Comparative Example 1, abietic acid powder; in Comparative Example 2, rosin powder) were immersed in distilled water, and an aqueous dispersion was prepared under the same conditions as in Example 1. Thereafter, in the same manner as in Example 1, the elution amount of abietic acid into distilled water was calculated from the measurement results of the concentration of abietic acid in the supernatant of the resin acid eluate by ultraviolet absorption photometry.

[0089] The measurement results of the elution rate of abietic acid for the samples of Examples 1 to 13 and Comparative Examples 1 to 4 are shown in Table 1 below.

[0090]

Table 1

[0091] As shown in Table 1, in the samples of Examples 1 to 13, by shaking after immersion in distilled water, the matrix either disappeared from its original form and eluted into distilled water, or eluted substantially into distilled water leaving only a small amount of precipitate. On the other hand, in the samples of Comparative Examples 3 to 4, even by shaking after immersion in distilled water, the matrix eluted into distilled water only to the extent of retaining or substantially retaining its original form. From these results, it was confirmed that a resin acid composition containing a water-soluble matrix composed of at least one selected from the group consisting of methylcellulose, hydroxypropylmethylcellulose, and carboxymethylcellulose can suppress insoluble matter in water as compared with a resin acid composition containing only a water-insoluble organic matrix without containing a water-soluble organic matrix.

[0092] From the above results, it is presumed that a resin acid composition containing a water-soluble matrix composed of a water-soluble cellulose derivative can suppress insoluble matter when eluted in distilled water.

[0093] In particular, in the samples of Examples 1 to 2, 4 to 9 where the weight ratio of rosin acid to the matrix was 10 / 90, the matrix disappeared from its original form and eluted into distilled water by shaking after immersion in distilled water. In contrast, in the sample of Example 10 where the weight ratio of rosin acid to the matrix was 20 / 80, the matrix left only a small amount of precipitate. From these results, in a rosin acid-containing composition comprising a water-soluble matrix composed of at least one selected from the group consisting of methylcellulose and hydroxypropylmethylcellulose, and where the weight ratio of abietic acid or rosin to the water-soluble matrix is less than 20 / 80, it was confirmed that the matrix elutes into distilled water to such an extent that it cannot be visually recognized.

[0094] Considering the above results, in the rosin acid-containing composition of the above components, for example, when the weight ratio of rosin acid to the matrix is 1 / 99 or more and 15 / 85 or less, in some cases 5 / 95 or more and 15 / 95 or less, and further 8 / 92 or more and 12 / 88 or less, it is presumed that a good elution state of the matrix into distilled water can be obtained.

[0095] In the samples of Examples 1 to 13, the elution rate of abietic acid into distilled water after 30 minutes exceeded 20.0%, and in the samples of Examples 1 to 4, the elution rate of abietic acid into distilled water after 28 days also exceeded 20.0%. On the other hand, in the samples of Comparative Examples 1 to 4, the elution rate of abietic acid into distilled water after 30 minutes was less than 20%, and in the samples of Comparative Examples 1 to 2, the elution rate of abietic acid into distilled water after 28 days was less than 6.0%. From these results, a rosin acid-containing composition in which abietic acid or rosin is dispersed in a matrix mainly composed of at least one selected from the group consisting of methylcellulose, hydroxypropylmethylcellulose, and carboxymethylcellulose elutes abietic acid into distilled water at a high elution rate when eluted in distilled water, as compared with a rosin acid composition in which abietic acid is dispersed in a matrix composed only of a water-insoluble organic matrix. This was confirmed.

[0096] In particular, in the samples of Examples 1-2 and Examples 4-12, the elution rate of abietic acid into distilled water after 30 minutes exceeded 35.0%. From these results, it was confirmed that a resin acid-containing composition in which at least one selected from the group consisting of methyl cellulose and hydroxypropyl methyl cellulose is contained as a main component and abietic acid or rosin is dispersed in a matrix composed of all water-soluble cellulose derivatives elutes abietic acid into distilled water at a higher elution rate when eluted in distilled water.

[0097] In the samples of Examples 1-2, Examples 4-5, and Examples 8-12, the elution rate of abietic acid into distilled water after 30 minutes exceeded 40.0%. From these results, it was confirmed that a resin acid-containing composition in which at least one of methyl cellulose and hydroxypropyl methyl cellulose (excluding those eluted in tetrahydrofuran) is contained as a main component and abietic acid or rosin is dispersed in a matrix composed of all water-soluble cellulose derivatives elutes abietic acid into distilled water at an even higher elution rate.

[0098] Referring to Examples 1 and Examples 10-12, in the samples of Examples 1 and Examples 10-11, the elution rate of abietic acid into distilled water after 30 minutes exceeded 60.0%. On the other hand, in the sample of Example 12, the elution rate of abietic acid into distilled water after 30 minutes was less than 50.0%. From these results, regarding a resin acid-containing composition composed of methyl cellulose and abietic acid, it was confirmed that when the weight ratio of the resin acid to the water-soluble organic matrix is less than 40 / 60, the resin acid elutes into distilled water at a higher elution rate.

[0099] Considering the above results, in a resin acid-containing composition composed of methyl cellulose and abietic acid, for example, when the weight ratio of the resin acid to the matrix is 1 / 99 or more and 35 / 65 or less, and in some cases 5 / 95 or more and 35 / 65 or less, and further 8 / 92 or more and 32 / 68 or less, it is presumed that a high elution state of the resin acid can be obtained.

[0100] Next, in order to evaluate the antibacterial properties of the resin acid-containing composition, samples of Examples 14 to 17 and Comparative Examples 5 to 7 were prepared as follows.

[0101] <Example 14> A mixed solution was prepared by mixing 32.5 g of an aqueous solution containing 0.25% by weight of methyl cellulose (manufactured by Nacalai Tesque, Inc.) and 1.5 g of an acetone solution containing 0.6% by weight of abietic acid (manufactured by Nacalai Tesque, Inc.). The prepared mixed solution was subjected to ultrasonic treatment twice for 5 minutes using an ultrasonic homogenizer (product name "US-150E" manufactured by Nippon Seiki Co., Ltd.). Next, the entire amount of the mixed solution was poured into a Teflon (registered trademark) petri dish with a diameter of 90 mm and dried at room temperature in air for 2 days. As a result, a film-like solid sample of a resin acid-containing composition with a weight ratio of abietic acid to methyl cellulose of about 10 / 90 was obtained.

[0102] <Example 15> A mixed solution was prepared by mixing 32.5 g of an aqueous solution containing 0.25% by weight of hydroxypropylmethyl cellulose (manufactured by Santa Cruz Biotechnology) and 1.5 g of an acetone solution containing 0.6% by weight of abietic acid (manufactured by Nacalai Tesque, Inc.). The prepared mixed solution was subjected to ultrasonic treatment and drying treatment in the same manner as in Example 14. As a result, a film-like solid sample of a resin acid-containing composition with a weight ratio of abietic acid to hydroxypropylmethyl cellulose of about 10 / 90 was obtained.

[0103] <Example 16> 32.5 g of an aqueous solution containing 0.25 wt% of carboxymethyl cellulose (sodium salt) (manufactured by Nacalai Tesque, Inc.) and 1.5 g of an acetone solution containing 0.6 wt% of abietic acid (manufactured by Nacalai Tesque, Inc.) were mixed to prepare a mixed solution. The prepared mixed solution was subjected to ultrasonic treatment and drying treatment in the same manner as in Example 14. As a result, a film-like solid sample of a resin acid-containing composition having a weight ratio of abietic acid to carboxymethyl cellulose (sodium salt) of about 10 / 90 was obtained.

[0104] <Example 17> 32.5 g of an aqueous solution containing 0.25 wt% of methyl cellulose (manufactured by Nacalai Tesque, Inc.) and 1.5 g of an acetone solution containing 0.6 wt% of rosin (product name "Rogin, Gum" manufactured by Acros Organics) were mixed to prepare a mixed solution. The prepared mixed solution was subjected to ultrasonic treatment and drying treatment in the same manner as in Example 14. As a result, a film-like solid sample of a resin acid-containing composition having a weight ratio of rosin to methyl cellulose of about 10 / 90 was obtained.

[0105] <Comparative Example 5> 32.5 g of an aqueous dispersion containing 0.25 wt% of TEMPO-oxidized cellulose nanofibers (product name "Reocrista I-2SX" manufactured by Dai-ichi Kogyo Seiyaku Co., Ltd.) and 1.5 g of an acetone solution containing 0.6 wt% of abietic acid (manufactured by Nacalai Tesque, Inc.) were mixed to prepare a mixed solution. The prepared mixed solution was subjected to ultrasonic treatment and drying treatment in the same manner as in Example 14. As a result, a film-like solid sample of a resin acid-containing composition having a weight ratio of abietic acid to TEMPO-oxidized cellulose nanofibers of about 10 / 90 was obtained.

[0106] <Comparative Example 6> 4.8 g of an aqueous solution containing 0.25 wt% of a nonionic surfactant (product name "Tween-80" manufactured by Tokyo Chemical Industry Co., Ltd.) and 1.0 g of an acetone solution containing 5.9 wt% of abietic acid (manufactured by Nacalai Tesque, Inc.) were mixed. Thereby, an emulsion dispersion of abietic acid with a surfactant was obtained.

[0107] <Comparative Example 7> 4.8 g of an aqueous solution containing 0.25 wt% of a nonionic surfactant (product name "Tween-80" manufactured by Tokyo Chemical Industry Co., Ltd.) and 1.0 g of an acetone solution containing 5.9 wt% of rosin (product name "Rogin, Gum" manufactured by Acros Organics) were mixed. Thereby, an emulsion dispersion of rosin with a surfactant was obtained.

[0108] [Antibacterial Test] [Preparation of Standard Medium] 10 mL of distilled water was added to 0.2 g of potato dextrose agar (product name "Potato Dextrose Agar, suitable for microtechnology, NutriSelection Plus" manufactured by Merck Millipore). Thereafter, using an autoclave device (product name "TR-24LB" manufactured by ALP), the potato dextrose agar with distilled water added was autoclaved under the conditions of a temperature of 120°C and a treatment time of 20 minutes. The autoclaved potato dextrose agar was poured into a sterilized petri dish (product name "Disposable PS, sterilized" manufactured by MonotaRO Co., Ltd.) in a clean bench and cooled until it lost fluidity. This cooled potato dextrose agar was used as the standard medium.

[0109] [Preparation of Media for Examples 14 to 17 and Comparative Example 5] The film-like solid samples of Examples 14 to 17 and Comparative Example 5 were each placed on the standard medium, and potato dextrose agar was poured so as to cover the solid samples and cooled until it lost fluidity. Thereby, the media for Examples 14 to 17 were each prepared.

[0110] <Preparation of Media for Comparative Examples 6 - 7> After applying 0.88 g of the emulsified dispersions of Comparative Examples 6 - 7 onto the reference medium to form a coating layer, potato dextrose agar was poured onto the surface of the coating layer and cooled until it lost fluidity. Thereby, the media for Comparative Examples 6 - 7 were each prepared.

[0111] [Seeding and Cultivation of Mycelia] Using a cork borer with a diameter of 6 mm, oyster mushrooms (stock name "FFPRI 1030 (Kawara - tke)" obtained from the Genetic Resources Research Center, National Agriculture and Food Research Organization) were seeded in the center of the above - mentioned medium. The seeded medium was cultured in an incubator (product name "Cool Incubator" manufactured by Ikeda Sangyo Co., Ltd.) set at a temperature of 25°C for 7 days.

[0112] Next, as follows, two straight lines were set, and the growth of the mycelia was calculated from the diameter of the mycelial growth area. One straight line was set to pass through the center of the medium and point in the direction of the end of the most extended mycelia, and the other straight line was set to pass through the center of the medium and be perpendicular to the first straight line. On these two straight lines, the lengths of the straight lines were measured with the ends of the mycelia in the direction each straight line pointed as the endpoints of the straight line. The average value of the lengths of these two straight lines was taken as the diameter of the mycelial growth area.

[0113] [Calculation of Mycelial Growth Inhibition Rate] Using the calculated diameter of the mycelial growth area, the mycelial growth inhibition rate was determined from the following formula. Mycelial growth inhibition rate (%) = ((Diameter of the mycelial growth area in the reference medium) - (Diameter of the growth area in the example or comparative example)) / (Diameter of the mycelial growth area in the reference medium) × 100 The obtained growth inhibition rates are shown in Table 2 below.

[0114]

Table 2

[0115] As shown in Table 2, the media of Examples 14 to 17 showed a high mycelial growth inhibition rate exceeding 25.0%, being comparable to or higher than the growth inhibition rate of the media of Comparative Examples 5 to 7. From these results, it was confirmed that the resin acid-containing composition in which abietic acid or rosin is dispersed in a water-soluble organic matrix composed of methylcellulose, hydroxypropylmethylcellulose, or carboxymethylcellulose has antibacterial properties comparable to or higher than those of the resin acid alone, rosin alone, or the resin acid-containing composition in which abietic acid is dispersed in a water-insoluble organic matrix.

[0116] In particular, the media of Examples 14 to 15 and Example 17 showed a high mycelial growth inhibition rate exceeding 55.0%. From these results, it was confirmed that the resin acid-containing composition in which abietic acid or rosin is dispersed in a water-soluble matrix composed of methylcellulose or hydroxypropylmethylcellulose has higher antibacterial properties. Furthermore, the medium of Example 15 showed a high mycelial growth inhibition rate exceeding 60.0%. From this result, it was confirmed that the resin acid-containing composition in which abietic acid is dispersed in a water-soluble matrix composed of hydroxypropylmethylcellulose has even higher antibacterial properties.

Explanation of Symbols

[0117] 10 Resin acid-containing composition 11 Water-soluble organic matrix 12 Resin acid 13 Distilled water 20 Resin acid eluate 30 Container

Claims

1. A resin acid-containing composition comprising a water-soluble organic matrix and a resin acid, wherein the resin acid is dispersed in the water-soluble organic matrix, and the water-soluble organic matrix comprises at least one selected from the group consisting of methylcellulose, hydroxypropylmethylcellulose, and carboxymethylcellulose.

2. The resin acid-containing composition according to claim 1, wherein the water-soluble organic matrix contains methylcellulose.

3. The resin acid-containing composition according to claim 1, wherein the resin acid contains abietic acid.

4. The resin acid-containing composition according to claim 1, which is a solid.

5. A resin acid-containing composition comprising a water-soluble organic matrix and a resin acid, wherein the resin acid is dispersed in the water-soluble organic matrix, and the elution rate of the resin acid into distilled water, measured using the supernatant separated from the resin acid eluate by centrifugation immediately after preparing a resin acid eluate in which at least a part of the resin acid is eluted into distilled water by shaking for 30 minutes at a temperature of 37.0 ± 0.5 °C with respect to the resin acid-impregnated water obtained by immersing the resin acid-containing composition in distilled water, is 20.0% by weight or more.

6. The resin acid-containing composition according to claim 5, wherein the elution rate of the resin acid into distilled water, measured using the supernatant separated from the resin acid eluate by centrifugation immediately after preparing a resin acid eluate in which at least a part of the resin acid is eluted into distilled water by shaking for 30 minutes at a temperature of 37.0 ± 0.5 °C with respect to the resin acid-impregnated water obtained by immersing the resin acid-containing composition in distilled water, is 40.0% by weight or more.

7. The resin acid-containing composition according to claim 5, wherein the elution rate of the resin acid into distilled water, measured using the supernatant separated from the resin acid eluate by centrifugation immediately after preparing a resin acid eluate in which at least a part of the resin acid is eluted into distilled water by shaking for 28 days at a temperature of 37.0 ± 0.5 °C with respect to the resin acid-impregnated water obtained by immersing the resin acid-containing composition in distilled water, is 20.0% by weight or more.

8. The resin acid-containing composition according to claim 5, wherein the water-soluble organic matrix contains a water-soluble cellulose derivative.

9. ​ ​ ​ ​ ​ ​ ​ ​ ​ ​ the weight ratio of the resin acid to the water-soluble organic matrix is 1 / 99 or more and 50 / 50 or less, or, the resin acid-containing composition further comprises a water-insoluble matrix, and the weight ratio of the resin acid to the water-soluble organic matrix and the water-insoluble matrix is 1 / 99 or more and 50 / 50 or less, The resin acid-containing composition according to claim 5.

10. being in film form, The resin acid-containing composition according to claim 5.

11. comprising the resin acid-containing composition according to any one of claims 1 to 10, an antibacterial agent.

12. preparing a resin acid-containing liquid containing a resin acid and an organic solvent, preparing a mixed liquid containing the resin acid, the organic solvent, a water-soluble organic matrix, and water using the resin acid-containing liquid, removing at least a part of the organic solvent from the mixed liquid to obtain a resin acid-containing composition containing at least the resin acid and the water-soluble organic matrix, A method for producing a resin acid-containing composition, comprising:

13. the organic solvent contains at least one selected from the group consisting of acetone and tetrahydrofuran, The method for producing a resin acid-containing composition according to claim 12.

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