Polysaccharide-containing film, and method for producing the film.

Abstract

The present invention provides a skin bonding member that can be simplified and streamlined in terms of handleability, an application method, a skin bonding member configuration (component configuration and layer configuration), etc.　Provided is a film that contains a polysaccharide (A) having a sulfate group and sodium hyaluronate (B).

Description

Technical Field

[0001] The present invention relates to a polysaccharide-containing film and a method for producing the film.

Background Art

[0002] Currently, in the living environment, due to factors such as the deterioration of the life rhythm during the COVID-19 pandemic, the constant use of masks, and pollution caused by environmental pollution, the need to protect and maintain healthy skin is increasing. Especially among women in the East Asian region, there has been a continuous need to whiten the skin (so-called skin whitening) and keep the skin moisturized since ancient times. By the way, cosmetics are basically composed of various materials and are designed while taking into account the performance balance. For example, if the application method of cosmetics and the composition of cosmetic ingredients can be made simpler, it will be possible to give more scope to cosmetic design and efficacy. In addition to cosmetics, in the entire field related to skin-adhesive members aimed at enhancing the skin moisturizing effect, including medical preparations, it is desired to provide skin-adhesive members with a simpler structure. By the way, a skin-adhesive laminate formed by forming a layer containing a polysaccharide derived from Sargassum fusiforme on a support is known (for example, see Patent Document 1). Also, a skin-adhesive film formed by forming a composition containing Sargassum fusiforme polysaccharide (a), water (b), and polyhydric alcohol (c) into a film shape is known (for example, see Patent Document 2).

Prior Art Documents

Patent Documents

[0003]

Patent Document 1

Patent Document 2

Summary of the Invention

Problems to be Solved by the Invention

[0004] Suizenji-nori polysaccharide has high film-forming properties, which is an advantage when forming films with it, as it makes it easier to obtain uniform films. However, it has been found that films formed using Suizenji-nori polysaccharide alone are weak and easily broken. In the skin-laminated laminate described in Patent Document 1 above, in addition to the layer containing polysaccharides derived from Suizenji-nori, a support structure is required to support the layer. From the standpoint of ease of application and ease of handling, it is desirable that the skin-adhesive member be composed solely of a layer containing Suizenji-nori polysaccharide, without the use of a support. Furthermore, the gel film containing Suizenji Nori polysaccharide, water, and polyhydric alcohol described in Patent Document 2 is easy to prepare, but it has the problem of poor post-processing and handling properties. From the perspective of providing a skin-bonding member that is simpler and easier to handle, easier to apply, and has a more streamlined structure (component composition, layer composition, etc.), the skin-bonding members described in Patent Document 1 and Patent Document 2 above are not sufficient and there is room for improvement. Therefore, the present invention aims to provide a skin-adhesive member that can be made simpler and easier to use from the viewpoint of handling, application method, and the composition of the skin-adhesive member (component composition and layer composition). [Means for solving the problem]

[0005] As a result of diligent research to solve the above problems, the inventors have discovered a film characterized by containing a polysaccharide having a sulfate group (A) and sodium hyaluronate (B), thereby solving the above problems.

[0006] In other words, the present invention encompasses the following aspects. [1] A film containing a polysaccharide having a sulfate group (A) and sodium hyaluronate (B). [2] The film according to [1], wherein the sulfated polysaccharide (A) is a polysaccharide having a weight-average molecular weight in the range of 3 million to 30 million. [3] The film according to [1] or [2], wherein the content ratio of the sulfate-containing polysaccharide (A) and the sodium hyaluronate (B) is 80:20 to 20:80 in mass ratio of [sulfate-containing polysaccharide (A)]:[sodium hyaluronate (B)]. [4] The film according to any one of [1] to [3], wherein the combined mass ratio of the sulfated polysaccharide (A) and the sodium hyaluronate (B) in the film is 70% or more. [5] The film according to any one of [1] to [4], wherein the film contains other components (D) in addition to the sulfated polysaccharide (A) and sodium hyaluronate (B) and water (C) if present, the mass ratio of the other components (D) in the film is 10% or less. [6] The film according to any one of [1] to [5], wherein the sulfated polysaccharide (A) is a polysaccharide obtained from Suizenji-nori. [7] The film according to any one of [1] to [6], used as a skin-bonding member. [8] A step of preparing an aqueous solution (I) containing a polysaccharide (A) having a sulfate group, The process involves preparing an aqueous solution (II) containing sodium hyaluronate (B), A step of mixing the aqueous solution (I) and the aqueous solution (II) to obtain a mixed solution (III), A method for manufacturing a film, comprising the steps of: placing the mixed liquid (III) on a substrate; forming a coating film on the substrate; and then evaporating the water in the coating film to dry the coating film, thereby obtaining the film described in any of [1] to [7]. [Effects of the Invention]

[0007] The present invention provides a skin-adhesive member that is simpler and easier to use in terms of handling, application method, and the composition of the skin-adhesive member (component composition and layer composition). [Brief explanation of the drawing]

[0008] [Figure 1]These are photographs illustrating the appearance of the film during formation and the film after film formation in the examples and comparative examples. [Modes for carrying out the invention]

[0009] The present invention will be described in detail below. The following description of the constituent elements is illustrative for illustrating the present invention, and the present invention is not limited to these elements.

[0010] (film) The film of the present invention contains a polysaccharide having a sulfate group (A) and sodium hyaluronate (B). The film of the present invention may contain water (C) or other components (D) in addition to the above-mentioned polysaccharide having a sulfate group (A) and sodium hyaluronate (B).

[0011] The film of the present invention is formed into a film by molding a mixture of a sulfate-containing polysaccharide (A) and sodium hyaluronate (B), and refers to a film in which the layer containing the sulfate-containing polysaccharide (A) and sodium hyaluronate (B) forms a thin film structure on its own after molding, without the presence of a support. For example, in the present invention, a "film" is defined as something that can be rolled up and maintain flexibility, while a film that cannot be rolled up or whose layer breaks midway, lacking sufficient strength and flexibility to maintain a thin film structure on its own, is not considered a "film" in the present invention.

[0012] The film of this invention is intended to have a thickness on the order of μm. The thickness of the film of the present invention is preferably 1 to 200 μm, more preferably 1 to 100 μm, more preferably 1 to 50 μm, and even more preferably 5 to 40 μm.

[0013] <Polysaccharides containing sulfate groups (A)> As the polysaccharide (A) having a sulfate group used in the present invention, any polysaccharide having a sulfate group in a part of the polysaccharide may be used, and it is not particularly limited as long as the effects of the present invention can be obtained. However, a polysaccharide (A) having 1 to 30 moles of sulfate groups per 10 moles of constituent sugars of the polysaccharide is more preferable. The polysaccharide (A) having a sulfate group within such a range with respect to the constituent sugars of the polysaccharide is preferable because its hydration ability is well exhibited in a wide range of pH environments. As the polysaccharide (A) having a sulfate group, a sulfate group-containing polysaccharide extracted from various raw materials may be used as it is, or a polysaccharide obtained by introducing a sulfate group into a polysaccharide not containing a sulfate group by a known method may be used. Further, as the polysaccharide (A) having a sulfate group in the structure used in the present invention, salts of these polysaccharides may be used. The sulfate group contained in the polysaccharide (A) having a sulfate group can be determined by quantifying the content of sulfur atoms in contrast to the content of carbon atoms by elemental analysis.

[0014] As the polysaccharide (A) having a sulfate group used in the present invention, a polysaccharide having a sulfate group derived from cyanobacteria is preferable, and particularly, a Suizenji nori polysaccharide derivative obtained from Aphanothece sacrum (scientific name: Aphanothece sacrum) is preferable because it improves dispersion stability.

[0015] The Suizenji nori suitable as a raw material for the polysaccharide (A) having a sulfate group in the present invention is a kind of eubacteria belonging to the cyanobacteria Chroococcales and having photosynthetic ability. The above-mentioned Suizenji nori grows naturally in a specific region of Kyushu and is a freshwater cyanobacterium in which a plurality of cells form a flat-shaped colony. Further, the outer surface of the colony is covered with a gel-like secretion formed by a polysaccharide or the like, and the diameter of the colony grows to about 50 mm. Suizenji nori has been valued as a food since ancient times, is a material with rich food experience, and its safety is ensured.

[0016] A specific method for extracting the sulfate-containing polysaccharide (A) from the aforementioned Suizenji-nori is, for example, to remove water-soluble pigments by freezing and washing an appropriate amount of Suizenji-nori with water, then to remove lipid-soluble pigments with an organic solvent such as ethanol, and then to dry the Suizenji-nori algae. Subsequently, 0.1N sodium hydroxide is added to the dried Suizenji-nori algae and stirred at 60-80°C for 6 hours. The sugar derivative solution obtained from the above operation is neutralized and filtered, and further treated with a dialysis membrane with a molecular weight cutoff of 8,000, and the solution inside the dialysis membrane is concentrated and dried.

[0017] The polysaccharide derived from Suizenji-nori used in this invention is also known by the name "Sacran" (a registered trademark of Green Science Material Co., Ltd.).

[0018] Furthermore, the sulfated polysaccharide (A) used in the present invention may be one or more selected from the group consisting of heparan sulfate, chondroitin sulfate, dermatan sulfate and their salts, in addition to polysaccharides derived from Suizenji Nori; or one or more selected from the group consisting of polysaccharides having sulfated groups in part of known polysaccharides composed of D-glucosamine, D-galactosamine, D-glucuronic acid, L-iduronic acid, D-galacturonic acid, D-glucose, D-galactose, D-xylose, etc., and their salts. These components may be used individually, or two or more may be used in appropriate combinations.

[0019] The weight-average molecular weight of the sulfate-containing polysaccharide (A) used in the present invention is not particularly limited as long as the effects of the present invention can be obtained, but is preferably 3 million to 30 million, more preferably 3.5 million to 25 million, even more preferably 3.5 million to 20 million, and particularly preferably 4 million to 15 million.

[0020] <Sodium hyaluronate (B)> The weight-average molecular weight of sodium hyaluronate (B) used in the present invention is not particularly limited within the range in which the effects of the present invention can be obtained, but is preferably 600,000 to 2,500,000, and more preferably 1,200,000 to 2,000,000.

[0021] Polysaccharides (A) containing sulfate groups have high film-forming capabilities. When polysaccharides (A) containing sulfate groups are used alone to form a film, a uniform film is easily obtained, but in that form, the film is weak, easily breaks, and does not have the durability required for a film. Therefore, in this invention, sodium hyaluronate (B) is added. By forming a film using a polysaccharide having a sulfate group (A) and sodium hyaluronate (B), a film with excellent uniformity and high strength can be obtained. Polysaccharide (A) containing sulfate groups has an extremely high molecular weight, making it difficult to obtain sufficient mechanical strength (torsional strength (flexural strength)) on its own. However, we hypothesize that by combining it with sodium hyaluronate, which is also a polysaccharide, the dispersion balance between the resins improves, thereby enhancing the mechanical strength of the film.

[0022] <Content ratio of sulfate-containing polysaccharides (A) and sodium hyaluronate (B)> As described above, the film of the present invention contains a polysaccharide (A) having a sulfate group and sodium hyaluronate (B), resulting in a highly uniform and strong film. Incidentally, it has been found that when sodium hyaluronate is used alone to form a film, film shrinkage becomes a problem. Extremely high concentrations of sodium hyaluronate cause this film shrinkage problem. Therefore, in order to compensate for both the weakness of the sulfate-containing polysaccharide (A) (weak film strength) and the weakness of sodium hyaluronate (B) (film shrinkage) when a film is formed, and to obtain a uniform, high-strength film without shrinkage, it is desirable to adjust the content ratio of sulfate-containing polysaccharide (A) and sodium hyaluronate (B). In the film of the present invention, for example, the content ratio of a sulfate-containing polysaccharide (A) and sodium hyaluronate (B) is preferably 80:20 to 20:80, more preferably 75:25 to 25:75, and even more preferably 70:30 to 50:50, in terms of the mass ratio of [sulfate-containing polysaccharide (A)]:[sodium hyaluronate (B)]. A film in which the content ratio of a sulfated polysaccharide (A) and sodium hyaluronate (B) is within the above range can be made into a uniform, high-strength film that does not shrink. Polysaccharide (A) containing sulfate groups has an extremely high molecular weight, making it difficult to obtain sufficient mechanical strength (torsional strength (flexural strength)) on its own. However, by blending it with sodium hyaluronate, another polysaccharide, in a favorable proportion, the dispersion balance between the resins is improved, and the mechanical strength of the film can be enhanced while suppressing the shrinkage of sodium hyaluronate.

[0023] In the film of the present invention, the combined mass ratio of the sulfate-containing polysaccharide (A) and sodium hyaluronate (B) is preferably 70% or more, more preferably 80%, more preferably 85%, more preferably 90%, even more preferably 95%, and even more preferably 98%. The film of the present invention may also be composed only of the sulfate-containing polysaccharide (A) and sodium hyaluronate (B), and the combined mass ratio of the sulfate-containing polysaccharide (A) and sodium hyaluronate (B) may be 100%.

[0024] The film of the present invention is preferably in a dry state, but it may contain some moisture as long as it has sufficient film strength to maintain its shape even without a support. In the film of the present invention, the water (C) content is preferably 30% or less by mass, more preferably 20% or less, even more preferably 10% or less, and particularly preferably 5-6% or less.

[0025] The film of the present invention may contain other components (D) as described above. Other components (D) include, for example, any oils that can be used in the cosmetics or medical fields, moisturizers such as glycerin, anti-inflammatory components such as dipotassium glycyrrhizate and allantoin, antioxidant components such as ascorbic acid and their esters, astringent components, whitening components, skin-improving components, surfactants, UV protection agents, plant and animal-derived extracts, higher alcohols, antioxidants, colorants, pH adjusters, fragrances, preservatives, and polysaccharides other than components (A), when the film is used in the cosmetics or medical fields.

[0026] In the film of the present invention, if other components (D) are included in addition to a polysaccharide (A) having a sulfate group, sodium hyaluronate (B), and water (C) if present, the mass percentage of the other components (D) in the film is preferably 10% or less, more preferably 8% or less, and even more preferably 4-5% or less.

[0027] <Film manufacturing method> The film of the present invention can be obtained by forming (forming) a film of a mixture of a polysaccharide having a sulfate group (A) and sodium hyaluronate (B). One method for forming the film is to use a solution (coating solution) containing a polysaccharide having a sulfate group (A) and sodium hyaluronate (B). When using the coating solution, the solid content concentration is usually 0.05 to 0.5% by mass.

[0028] As a more specific method for manufacturing the film of the present invention, for example, a manufacturing method including the following steps can be cited. The present invention's method for manufacturing a film is: A step of preparing an aqueous solution (I) containing a polysaccharide (A) having a sulfate group, The process involves preparing an aqueous solution (II) containing sodium hyaluronate (B), The process involves mixing the above aqueous solution (I) and the above aqueous solution (II) to obtain a mixed solution (III), The process includes the steps of: placing the above-mentioned mixed liquid (III) on a substrate, forming a coating film on the substrate, and then evaporating the water in the coating film to dry the coating film and thereby obtaining a film. In this case, the conditions for drying include, for example, a temperature of 70°C or lower and a drying time of 48 hours or less.

[0029] <Film Usage> Because the film of the present invention has excellent skin moisturizing properties, it can be used appropriately in various applications where skin moisturizing is required. For example, it can be used as a skin-adhering component in cosmetic films for skin application, cosmetic masks, and medical film formulations.

[0030] The film of the present invention may be a dry film or a moist film containing some moisture. As long as the presence of moisture does not cause a loss of strength as a layer, preventing film formation or causing the film to break, a film that can maintain a thin film structure on its own can be formed, even if it contains moisture. The film of the present invention can be used by adhering it to the skin surface. No support is required, and the film layer alone can be directly contacted and bonded to the skin. Furthermore, to make adhesion to the skin more effective, moisture may be supplied to the film when applying it to the skin to improve its moisture content before adhering the film to the skin. As described above, the film of the present invention can maintain a thin film structure with each layer alone, and therefore, from the viewpoint of maintaining the shape of the film, a support is not required. However, for example, to prevent contact between films during film winding or to consider convenience when applying the film to the user, it may be used in a configuration in which a film other than the film of the present invention, such as a release film, is laminated onto the film of the present invention.

[0031] <Specific uses of the film> Since the film of the present invention can exhibit a sustained-release function by becoming water-soluble, its use can also be considered in applications that utilize this function. For example, by incorporating a functional substance into the film of the present invention, the functional substance can be released from the film into the stratum corneum of the skin over time. Examples of functional substances include ingredients used in cosmetics. For example, functional substances include vitamins and vitamin derivatives, hydroquinone and its derivatives, whitening ingredients, anti-inflammatory ingredients, antioxidant ingredients, blood circulation promoting ingredients, cell activating ingredients, coenzymes and their intermediate metabolites, sugars, plant extracts, peptides, proteins, and pigments. More specifically, examples include ascorbic acid, ascorbic acid esters, dipotassium glycyrrhizinate, allantoin, vitamin A compounds, and vitamin E compounds. Note that the example compounds listed here include not only water-soluble but also oil-soluble raw materials. As long as the functional substance impregnated into the film of the present invention is supplied to the skin over time due to the sustained-release function described above, there are no particular restrictions on whether the functional substance is water-soluble or oil-soluble. [Examples]

[0032] The present invention will be described in more detail below with reference to examples, but the present invention is not limited to these examples.

[0033] <Preparation of polysaccharides containing sulfate groups> Frozen Aphanothece sacrum was thawed, and debris and water-soluble pigments were removed by rinsing with running water. Next, the mixture was stirred in an ethanol aqueous solution for 24 hours to remove lipid-soluble pigments. After that, the Aphanothece sacrum was removed from the ethanol and subjected to hydrolysis treatment by exposing it to a sodium hydroxide aqueous solution (0.05N) heated to 40°C for 2 hours to obtain an aqueous solution of Aphanothece sacrum polysaccharide.

[0034] The aqueous solution of Suizenji-nori polysaccharide obtained by the above process was filtered using a filter cloth, and the filtrate was placed into a dialysis membrane with a molecular weight cutoff of 8,000. Dialysis was performed in distilled water until the non-dialysis solution had a pH of approximately 9.0 to obtain a Suizenji-nori polysaccharide derivative solution.

[0035] A solution of Suizenji-nori polysaccharide derivative was added to isopropanol and stirred to obtain a fibrous Suizenji-nori polysaccharide derivative.

[0036] The obtained Suizenji Nori polysaccharide derivative was analyzed by conventional methods, and it was confirmed that the polysaccharide has 15 mol% sulfate groups in its structure as a percentage of sugar residues.

[0037] The Suizenji Nori polysaccharide derivative obtained above was fractionated by ultrafiltration to prepare a Suizenji Nori polysaccharide derivative with a weight-average molecular weight of 5 million, which will be used in the following examples.

[0038] <Preparation of aqueous solutions of polysaccharides containing sulfate groups and aqueous solutions of sodium hyaluronate> A Suizenji-nori polysaccharide derivative with a weight-average molecular weight of 5 million, measured by multi-angle scattering GPC, was weighed out, water was added, and the mixture was stirred with a stirrer at 80°C for 8 hours to prepare a 0.2% by mass aqueous solution of the Suizenji-nori polysaccharide derivative.

[0039] A 0.2% by mass aqueous solution of sodium hyaluronate was prepared by weighing out a high molecular weight polysaccharide (weight-average molecular weight 2 million), adding water, and stirring with a stirrer at 40°C for 1 hour. The sodium hyaluronate used was FCH-200 manufactured by Kikkoman Biochemifa Corporation.

[0040] (Example 1) An aqueous solution of 0.2% by mass of Suizenji Nori polysaccharide derivative and an aqueous solution of 0.2% by mass of sodium hyaluronate were prepared, and the two solutions were mixed in a ratio of 75:25 (by mass) of the Suizenji Nori polysaccharide derivative aqueous solution to the sodium hyaluronate aqueous solution. After mixing, 25 g of the mixture was poured into a 4.5 cm × 4.5 cm polystyrene petri dish and dried at atmospheric pressure, 40°C, for 24 hours to obtain a non-shrinking, uniform, and high-strength film.

[0041] <Shrinkage suppression evaluation> The area of ​​the obtained film was converted to 100% of the area of ​​the petri dish (4.5 cm × 4.5 cm). [Evaluation Criteria] 4: Film area is 95% or more to 100% of the petri dish area. 3: Film area is 90% or more but less than 95% of the petri dish area. 2: The film area is 80% or more but less than 90% of the petri dish area. 1: Film area is less than 80% of Petri dish area. In each evaluation, a higher number indicates a better result. For example, in the evaluation results, "4" represents the best result, and "3" represents the next best result. On the other hand, "1" represents the worst result (the same applies to the numbers in other evaluation results).

[0042] <Rigidity (bending strength) evaluation> The film was folded in two directions, and the number of folds required before it broke was evaluated. [Evaluation Criteria] 4: 9 times or more 3: 8 times or more but less than 9 times 2: 7 times or more but less than 8 times 1: 1 or more times, but less than 7 times

[0043] <Evaluation of film homogeneity> Using a thickness gauge manufactured by Mitutoyo Corporation, the thickness was measured at a total of nine locations (three vertically and three horizontally), and the film uniformity was evaluated from the percentage variation from the average value. [Evaluation Criteria] 4: Variation within ±10% 3: Variation is greater than ±10% but within 20% 2: Variation is greater than ±20% but within 30% 1: Variation is greater than ±30%

[0044] The evaluation results of these tests are shown in Table 1. Figure 1 shows photographs of the film formation process in a polystyrene petri dish, and photographs showing the condition of the film after formation and during each evaluation test. In Figure 1, the upper photograph in the column for Example 1 shows the film in the process of formation, and the lower photograph shows the film after film formation.

[0045] (Examples 2-4) In Example 1, a film was obtained in the same manner as in Example 1, except that the ratio of aqueous solution of Suizenji Nori polysaccharide derivative to aqueous solution of sodium hyaluronate was changed to 70:30 (mass%), 50:50 (mass%), or 25:75 (mass%). A non-shrinking, uniform, and high-strength film was obtained. The film was evaluated using the same method as in Example 1. The evaluation results are shown in Table 1. Figure 1 also shows the condition of the films during and after formation for Examples 2-4.

[0046] (Comparative Example 1) A film was obtained in the same manner as in Example 1, except that the ratio of aqueous solution of Suizenji Nori polysaccharide derivative to aqueous solution of sodium hyaluronate was changed to 100:0 (mass%). The film was evaluated using the same method as in Example 1. The evaluation results are shown in Table 1. Figure 1 also shows the film during the formation process and the film after film formation for Comparative Example 1.

[0047] (Comparative Example 2) In Example 1, a film was obtained in the same manner as in Example 1, except that the ratio of aqueous solution of Suizenji Nori polysaccharide derivative to aqueous solution of sodium hyaluronate was changed to 0:100 (mass%). Shrinkage occurred, resulting in a non-uniform film that could not maintain a thin film structure on its own. The film was evaluated using the same method as in Example 1. The evaluation results are shown in Table 1. Figure 1 also shows the film during the formation process and the film after film formation for Comparative Example 1.

[0048] [Table 1]

[0049] As shown in Table 1, the film of the present invention is formed using a polysaccharide (A) having a sulfate group and sodium hyaluronate (B), resulting in a film with excellent uniformity and high strength. In addition, as shown in Figure 1, the films containing Suizenji Nori polysaccharide and sodium hyaluronate in Examples 1-3 had sufficient strength after film formation and were able to maintain their shape well. On the other hand, the film of Comparative Example 1, which did not contain sodium hyaluronate, lacked strength and stiffness and was prone to wrinkling. Furthermore, the film of Comparative Example 2, which did not contain Suizenji Nori polysaccharide, lacked water retention capacity and was unable to retain moisture, failing to maintain its structure as a film and shrinking significantly as moisture escaped. The film of the present invention can maintain its film shape on its own, thus eliminating the need for a support and allowing for application with a simpler configuration. Furthermore, since the base material of the skin-compounding component can be composed only of a polysaccharide having sulfate groups (A) and sodium hyaluronate (B), it has a fewer component composition. Therefore, the film of the present invention is a simpler and more convenient skin-adhesive member in terms of handling, application method, and the composition of the skin-adhesive member (component composition and layer composition).

Claims

1. A film containing a polysaccharide having a sulfate group (A) and sodium hyaluronate (B), The aforementioned polysaccharide (A) having a sulfate group is a polysaccharide obtained from Suizenji-nori, The weight-average molecular weight of the aforementioned polysaccharide (A) having a sulfate group is between 3.5 million and 20 million. The weight-average molecular weight of the sodium hyaluronate (B) is 600,000 to 2,500,000. A film in which the content ratio of the sulfate-containing polysaccharide (A) and the sodium hyaluronate (B) is 80:20 to 20:80 in mass ratio of [sulfate-containing polysaccharide (A)]:[sodium hyaluronate (B)].

2. The film according to claim 1, wherein the combined mass ratio of the sulfated polysaccharide (A) and the sodium hyaluronate (B) in the film is 70% or more.

3. The film according to claim 1, wherein, in addition to the sulfated polysaccharide (A) and sodium hyaluronate (B), and water (C) if present, the film contains other components (D), the mass ratio of the other components (D) in the film is 10% or less.

4. The film according to claim 1, wherein the film is used as a skin-bonding member.

5. A step of preparing an aqueous solution (I) containing a polysaccharide (A) having a sulfate group, The process involves preparing an aqueous solution (II) containing sodium hyaluronate (B), A step of mixing the aqueous solution (I) and the aqueous solution (II) to obtain a mixed solution (III), A method for manufacturing a film, comprising the steps of: placing the mixed liquid (III) on a substrate, forming a coating film on the substrate, and then evaporating the water in the coating film to dry the coating film, thereby obtaining the film according to any one of claims 1 to 4.

Images