Bag

Abstract

The present invention relates to a bag comprising a water-soluble film containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and derivatives thereof.

Description

Technical Field

[0001] The present invention relates to bags comprising a water-soluble film, laminates comprising a water-soluble film and a support, and coating agents for forming water-soluble films. Background Technology

[0002] A known method involves packaging a liquid medicine in a water-soluble film to form a bag, which is then placed in water in its bag-like state to dissolve the contents along with the film before use (Patent Document 1).

[0003] Existing technical documents

[0004] Patent documents

[0005] Patent Document 1: Japanese Patent Application Publication No. 2019-081901 Summary of the Invention

[0006] The problem that the invention aims to solve

[0007] For example, when using a bag filled with detergent or similar products, if the bag has low solubility in cold water, the dissolution process will be time-consuming, potentially leaving residue on the clothing. Furthermore, this is especially true when the bag contains polysaccharides, which sometimes have low solubility in cold water. Additionally, the bag itself needs mechanical strength to prevent breakage during transport.

[0008] Therefore, the object of the present invention is to provide a bag comprising a water-soluble film with excellent solubility and mechanical strength at low temperatures, a laminate comprising a water-soluble film and a support, and a coating agent for forming the water-soluble film.

[0009] Methods for solving problems

[0010] To address the aforementioned problems, the inventors conducted repeated and detailed studies, and as a result, discovered solutions to these problems, thus completing this invention. Specifically, this invention includes the following preferred embodiments.

[0011] [1] A bag comprising a water-soluble membrane containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and derivatives thereof.

[0012] [2] According to the bag described in [1], wherein the polysaccharide A is selected from tamarind gum and its derivatives.

[0013] [3] According to the bag described in [1] or [2], the content of the polysaccharide A is 5 to 80% by mass relative to the mass of the water-soluble film described above.

[0014] [4] The bag according to any one of [1] to [3], wherein the water-soluble film further contains a plasticizer.

[0015] [5] The bag according to [4], wherein the plasticizer is at least one selected from the group consisting of polyols, hydroxy acids, monosaccharides and disaccharides.

[0016] [6] The bag according to [4] or [5], wherein the plasticizer is at least one selected from the group consisting of glycerol, diglycerol, sorbitol, alkylene glycol, polyalkylene glycol, trimethylolpropane, erythritol, 2-methyl-1,3-propanediol, lactic acid, glucose, fructose, maltose and trehalose.

[0017] [7] The bag according to any one of [4] to [6], wherein the plasticizer is at least one selected from the group consisting of glycerol, ethylene glycol, sorbitol and fructose.

[0018] [8] The bag according to any one of [4] to [7], wherein the content of the plasticizer is 20 to 95% by mass relative to the mass of the water-soluble film.

[0019] [9] The bag according to any one of [1] to [8], wherein the water-soluble film further contains a polysaccharide B that is different from the polysaccharide A.

[0020]

[10] According to the bag described in [9], wherein the polysaccharide B is at least one selected from the group consisting of guar gum, locust bean gum, xanthan gum, carrageenan, alginate, pullulan and their derivatives.

[0021]

[11] According to the bag described in [9] or

[10] , the content of the polysaccharide B is 1 to 30 by mass relative to the mass of the water-soluble film described above.

[0022]

[12] The bag according to any one of [1] to

[11] , wherein the toughness value of the water-soluble film is 400 or more.

[0023]

[13] The bag according to any one of [1] to

[12] dissolves in water at 10°C within 1000 seconds.

[0024]

[14] The bag according to any one of [1] to

[13] contains inside at least one selected from the group consisting of detergent, fabric softener and fragrance.

[0025]

[15] A water-soluble membrane containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and their derivatives.

[0026]

[16] A water-soluble membrane containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and their derivatives, and a polysaccharide B different from the above polysaccharide A.

[0027]

[17] A water-soluble film for use in bags, comprising at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and derivatives thereof, and a plasticizer, wherein the content of the plasticizer is 45% by mass or less relative to the mass of the water-soluble film.

[0028]

[18] The water-soluble film according to any one of

[15] to

[17] is a coated film formed by a coating agent containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and their derivatives.

[0029]

[19] A laminate comprising a water-soluble membrane and a support as described in any one of

[15] to

[17] , wherein the support is paper or membrane.

[0030]

[20] A packaging material comprising the water-soluble film described in

[15] .

[0031]

[21] A coating agent containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and their derivatives.

[0032] Invention Effects

[0033] According to the present invention, it is possible to provide bags comprising a water-soluble film with excellent solubility and mechanical strength at low temperatures, laminates comprising a water-soluble film and a support, and coating agents for forming the water-soluble film. Detailed Implementation

[0034] The embodiments of the present invention will now be described in detail. It should be noted that the following description is illustrative of embodiments of the present invention and is not intended to limit the present invention to these embodiments. It should also be noted that the multiple upper and lower limits described in this specification can be arbitrarily combined to form preferred numerical ranges.

[0035] [bag]

[0036] The bag of the present invention comprises a water-soluble film containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and their derivatives.

[0037] <Polysaccharide A>

[0038] Tamarind gum is a polysaccharide obtained from the seeds of the tamarind tree (Tamarindus indica). It has a structure with glucose as the main chain and xylose and galactose bonded to the side chains. Commercially available tamarind gum products include "GLYLOID 6C (registered trademark)," "GLYLOID (registered trademark)," "GLYLOID 3S (registered trademark)," "GLYLOID 2A (manufactured by MP GOKYO FOOD & CHEMICAL Co., Ltd.)," and "TG120 (manufactured by Mitsubishi Chemical Co., Ltd.)."

[0039] Locust bean gum is a polysaccharide obtained from the seeds of the locust bean (Celatonia siliqua). It has a structure with mannose as the main chain and galactose bonded to the side chains. Commercially available products such as "SOALOCUST A120", "SOALOCUST A200", "MC1000" (manufactured by Mitsubishi Chemical Corporation) and GRINSTED LBG 860 (manufactured by Sanshoku Corporation) can be used as locust bean gum.

[0040] Tara gum is a polysaccharide obtained from the seeds of the tara (Caesalpinia spinosa) plant. It has a structure with mannose as the main chain and galactose bonded to the side chains. Commercially available tara gum products include "MT120", "MT1000" (manufactured by Mitsubishi Chemical Co., Ltd.), and Spinogam D (manufactured by Sanshoku Co., Ltd.).

[0041] Examples of derivatives of polysaccharide A include anions obtained by introducing carboxyl methyl groups, and their sodium, potassium, and calcium salts; anions obtained by introducing quaternary ammonium groups, and their chlorides; ethers obtained from ethylene oxide or propylene oxide; enzyme-treated products; and acid hydrolysates. Polysaccharide A can be used alone or in combination with two or more.

[0042] In one embodiment of the present invention, the number-average molecular weight (sometimes expressed as Mn) of polysaccharide A is preferably 5k to 50,000 kDa, more preferably 7k to 10,000 kDa, and even more preferably 10k to 5,000 kDa, for example, 10k to 3,000 kDa, 15k to 1,000 kDa, or 20 to 700 kDa. Furthermore, the weight-average molecular weight (sometimes expressed as Mw) of polysaccharide A is preferably 5k to 150,000 kDa, more preferably 10k to 50,000 kDa, and even more preferably 20k to 30,000 kDa, for example, 30k to 10,000 kDa, 50k to 7,000 kDa, or 70k to 5,000 kDa. If the Mn and / or Mw of polysaccharide A are within the above ranges, the solubility and mechanical strength of the bag at low temperatures can be improved. When polysaccharide A is composed of two or more polysaccharides, the Mn of polysaccharide A is a weighted average of the Mn values ​​of the two or more polysaccharides. The same applies to Mw.

[0043] In one embodiment of the present invention, the Mn of tamarind gum is preferably 10k to 3000 kDa, more preferably 30k to 1000 kDa, and even more preferably 50k to 500 kDa, for example, 100k to 500 kDa. The Mw of tamarind gum is preferably 10k to 50000 kDa, more preferably 30k to 10000 kDa, and even more preferably 50k to 5000 kDa, for example, 500k to 4500 kDa or 1000k to 4000 kDa.

[0044] The Mn of locust bean gum is preferably 5k to 50,000 kDa, more preferably 7k to 10,000 kDa, and even more preferably 10k to 5,000 kDa, for example, 15 to 1,000 kDa or 20 to 300 kDa. The Mw of locust bean gum is preferably 5k to 150,000 kDa, more preferably 10k to 30,000 kDa, and even more preferably 15k to 15,000 kDa, for example, 20k to 5,000 kDa, 30k to 1,000 kDa or 50k to 500 kDa.

[0045] The Mn of tara gum is preferably 5k to 10000kDa, more preferably 7k to 5000kDa, and even more preferably 10k to 1000kDa. The Mw of tara gum is preferably 5k to 30000kDa, more preferably 10k to 15000kDa, and even more preferably 15k to 10000kDa.

[0046] If the Mn and / or Mw of each polysaccharide are within the above range, the solubility and mechanical strength of the bag at low temperatures can be improved. It should be noted that polysaccharide A may also contain the same type of polysaccharide with different Mn and / or Mw.

[0047] It should be noted that the Mn and Mw of these polysaccharides A can be determined by gel filtration HPLC, for example, by the methods described in the examples below.

[0048] The inventors, focusing on polysaccharides, unexpectedly discovered that films formed using at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and their derivatives exhibit excellent low-temperature solubility and mechanical strength. While the reasons for this are not yet fully understood, it is speculated that these polysaccharides A have sterically hindered side chains, thus easily suppressing crystallization, which is advantageous from a water solubility perspective. Furthermore, they can form higher-order networks through intermolecular interactions and hydrogen bonds, thereby easily improving mechanical strength. In addition, these polysaccharides A exhibit high heat resistance, acid resistance, and salt resistance, resulting in minimal molecular weight loss due to heating and dissolution during film manufacturing. Even when in contact with acidic or saline liquids, their physical properties change little, making them suitable for use in bags. Furthermore, they exhibit high resistance to enzymes such as amylase, thus making them suitable for applications such as enzyme-containing detergent bags.

[0049] Relative to the mass of the aforementioned water-soluble film, the content of polysaccharide A can be, for example, 0.1–100% by mass, 1–95% by mass, or 3–90% by mass, preferably 5–80% by mass, more preferably 10–70% by mass, even more preferably 20–60% by mass, even more preferably 25% by mass or more and less than 60% by mass, particularly preferably 30–58% by mass, even more preferably 32–55% by mass, even more preferably 35–50% by mass or 37–48% by mass. If the content of polysaccharide A is within the above range, the bag exhibits excellent solubility and mechanical strength at low temperatures.

[0050] In a preferred embodiment of the present invention, the polysaccharide A is preferably selected from tamarind gum and its derivatives. If polysaccharide A is selected from tamarind gum and its derivatives, the bag exhibits better solubility and mechanical strength at low temperatures. In a more preferred embodiment, the polysaccharide A is preferably selected from the group consisting of tamarind gum, sodium or potassium salts of tamarind gum anions, and enzyme-treated tamarind gum products.

[0051] <Plasticizers>

[0052] In the bags of the present invention, the water-soluble film preferably also contains a plasticizer. If the water-soluble film contains a plasticizer, it is easier to form the film and bag, thus improving processability. The plasticizer used in the bags of the present invention is preferably at least one selected from the group consisting of polyols, hydroxy acids, monosaccharides, and disaccharides. These compounds can cause polysaccharide A to aggregate through dehydration. Furthermore, by forming hydrogen bonds with polysaccharide A, a higher-order network can be formed, thus not only improving processability but also further improving the mechanical strength of the bag, particularly its elongation. A single plasticizer can be used, or two or more can be used in combination.

[0053] Examples of the aforementioned polyols include glycerol, diglycerol, sorbitol, alkylene glycols (e.g., ethylene glycol, propylene glycol, neopentyl glycol, etc., with 2 to 10 carbon atoms), polyalkylene glycols (e.g., diethylene glycol, triethylene glycol, tetraethylene glycol, polyethylene glycol with a molecular weight of less than 400, polypropylene glycol with a molecular weight of less than 400, etc.), trimethylolpropane, erythritol, xylitol, 2-methyl-1,3-propanediol, maltitol, mannitol, pentaerythritol, etc.

[0054] Examples of hydroxy acids mentioned above include lactic acid, glycolic acid, malic acid, and tartaric acid.

[0055] Examples of monosaccharides mentioned above include glucose, mannose, galactose, fructose, and xylose.

[0056] Examples of disaccharides mentioned above include maltose, trehalose, sucrose, and lactose.

[0057] From the viewpoint of further improving the mechanical strength of the bag, the plasticizer is preferably at least one selected from the group consisting of glycerol, diglycerol, sorbitol, alkylene glycol, neopentyl glycol, trimethylolpropane, erythritol, 2-methyl-1,3-propanediol, lactic acid, glucose, fructose, maltose and trehalose, more preferably at least one selected from the group consisting of glycerol, ethylene glycol, sorbitol and fructose.

[0058] Relative to the mass of the aforementioned water-soluble film, the plasticizer content can be, for example, 0–99.9% by mass, 5–99% by mass, or 10–95% by mass, preferably 20–95% by mass, more preferably 30–90% by mass, even more preferably 40–80% by mass, even more preferably greater than 40% by mass and less than 75% by mass, particularly preferably 42–70% by mass, even more preferably 45–68% by mass, and even more preferably 50–65% by mass or 52–63% by mass. If the plasticizer content is within the above range, the film has excellent processability and the bag has excellent mechanical strength.

[0059] In one embodiment of the present invention, the content ratio (mass ratio) of polysaccharide A to plasticizer is preferably 10:90 to 90:10, more preferably 20:80 to 80:20, further preferably 30:70 to 70:30, even more preferably 35:65 to 65:35, particularly preferably 36:64 to 60:40 or 37:63 to 58:42, particularly more preferably 38:62 to 55:45, and extremely preferably 39:61 to 52:48 or 40:60 to 50:50. If the content ratio of polysaccharide A to plasticizer is within the above range, the water solubility, mechanical strength, and low-temperature solubility of the water-soluble film can be improved. It should be noted that when the water-soluble film also contains polysaccharide B (described later), the content ratio (mass ratio) of polysaccharide A and polysaccharide B to plasticizer is preferably within the above range.

[0060] <Polysaccharide B>

[0061] In one embodiment of the invention, the water-soluble film in the bag preferably also contains a polysaccharide B, which is different from the polysaccharide A described above. If the water-soluble film also contains polysaccharide B, a higher-order network can be formed through hydrogen bonding with polysaccharide A, thereby further improving the mechanical strength of the bag.

[0062] As for polysaccharide B, from the viewpoint of further improving the mechanical strength of the bag, it is preferably selected from at least one of the group consisting of guar gum, locust bean gum, xanthan gum, carrageenan, alginate, pullulan, and their derivatives.

[0063] Guar gum is a polysaccharide obtained from the endosperm of guar beans (Cyamopsis tetragonoloba). It has a structure with mannose as the main chain and galactose bonded to the side chains. Commercially available guar gum products include "Garpak" (manufactured by MP GOKYO FOOD & CHEMICAL Co., Ltd., a registered trademark), "RG100" (manufactured by Mitsubishi Chemical Co., Ltd.), "JAGUAR C 17K" (manufactured by Sanjing Co., Ltd., cationic guar gum), and "MEYPRO-BOND 111" (manufactured by Sanjing Co., Ltd., cationic guar gum).

[0064] Xanthan gum is a polysaccharide produced by fermenting starch using the bacterium Xanthomonas campestris. It has a glucose backbone with side chains containing a glucuronic acid atom between two mannose molecules. Commercially available xanthan gum products include "Ekogam" (manufactured by MP GOKYO FOOD & CHEMICAL Co., Ltd., "SOAXAN", and "XG800" (manufactured by Mitsubishi Chemical Co., Ltd.).

[0065] Carrageenan is a polysaccharide obtained from red algae, containing repeating units of D-galactose or 3,6-lacto-D-galactose, and also containing sulfate groups. Carrageenan is classified as κ (Kappa) carrageenan, ι (Iota) carrageenan, and λ (Lambda) carrageenan. They can be used alone or in combination of two or more. Commercially available carrageenan products include, for example, "GENUGELcarrageenan type JPE-126" (manufactured by Mitsubishi Corporation), "GENUTINE VCS-J" (manufactured by Mitsubishi Corporation), "MW210", "MV320", and "MW952" (manufactured by Mitsubishi Chemical Corporation).

[0066] As derivatives of polysaccharide B, examples include sodium salts, potassium salts, calcium salts, cationic compounds and their salts, anionic compounds and their salts, enzyme-treated products, and acid hydrolysates. Polysaccharide B can be used alone or in combination of two or more.

[0067] In one embodiment of the present invention, the number-average molecular weight (sometimes expressed as Mn) of polysaccharide B is preferably 5k to 50,000 kDa, more preferably 10k to 10,000 kDa, and even more preferably 10k to 5,000 kDa, for example, 5k to 1,000 kDa, 10k to 500 kDa, or 15 to 200 kDa. Furthermore, the weight-average molecular weight (sometimes expressed as Mw) of polysaccharide B is preferably 5k to 150,000 kDa, more preferably 10k to 50,000 kDa, and even more preferably 10k to 30,000 kDa, for example, 10k to 5,000 kDa, 30k to 2,000 kDa, or 50k to 1,000 kDa. If the Mn and / or Mw of polysaccharide B are within the above ranges, the mechanical strength of the bag can be further improved. When polysaccharide B is composed of two or more polysaccharides, the Mn of polysaccharide B is a weighted average of the Mn values ​​of the two or more polysaccharides. The same applies to Mw.

[0068] In one embodiment of the present invention, the Mn of guar gum is preferably 5k to 20000 kDa, more preferably 5 to 10000 kDa, and even more preferably 7k to 5000 kDa, for example, 10k to 1000 kDa or 15k to 100 kDa. The Mw of guar gum is preferably 5k to 100000 kDa, more preferably 5k to 50000 kDa, and even more preferably 7k to 20000 kDa, for example, 10k to 5000 kDa, 30k to 1000 kDa or 50k to 500 kDa.

[0069] The Mn of xanthan gum is preferably 5k to 50,000 kDa, more preferably 7k to 10,000 kDa, and even more preferably 10k to 5,000 kDa, for example, 10k to 1,000 kDa or 15k to 100 kDa. The Mw of xanthan gum is preferably 5k to 150,000 kDa, more preferably 7k to 50,000 kDa, and even more preferably 10k to 30,000 kDa, for example, 10k to 5,000 kDa, 30k to 1,000 kDa or 50k to 500 kDa.

[0070] The Mn content of carrageenan is preferably 5k to 5000 kDa, more preferably 10k to 3000 kDa, and even more preferably 20k to 1000 kDa, for example, 25k to 500 kDa or 30k to 200 kDa. The Mw content of carrageenan is preferably 5k to 15000 kDa, more preferably 10k to 10000 kDa, and even more preferably 20k to 5000 kDa, for example, 50k to 2000 kDa or 100 to 1000 kDa.

[0071] The Mn of alginic acid is preferably 5k to 50,000 kDa, more preferably 7k to 10,000 kDa, and even more preferably 10k to 5,000 kDa, for example, 15 to 1,000 kDa or 20 to 300 kDa. The Mw of alginic acid is preferably 5k to 150,000 kDa, more preferably 10k to 30,000 kDa, and even more preferably 15k to 15,000 kDa, for example, 20k to 5,000 kDa, 30k to 1,000 kDa or 50k to 500 kDa.

[0072] If the Mn and / or Mw of each polysaccharide are within the above range, the mechanical strength can be further improved. It should be noted that polysaccharide B may also contain polysaccharides of the same type but with different Mn and / or Mw.

[0073] It should be noted that the Mn and Mw of these polysaccharides B can be determined by gel filtration HPLC, for example, by the methods described in the examples below.

[0074] In the aforementioned water-soluble film, polysaccharide A is preferably selected from tamarind gum or its derivatives, and polysaccharide B is preferably selected from at least one of the group consisting of xanthan gum, guar gum, and locust bean gum. Such a water-soluble film tends to improve mechanical strength while maintaining the bag's solubility at low temperatures.

[0075] The content of polysaccharide B relative to the mass of the water-soluble film is preferably 1 to 30% by mass, more preferably 1.5 to 20% by mass, even more preferably 2 to 10% by mass, even more preferably 2.5 to 7% by mass, and particularly preferably 3 to 5% by mass. If the content of polysaccharide B is within the above range, the bag exhibits excellent solubility and mechanical strength at low temperatures.

[0076] In one embodiment of the present invention, the content ratio (mass ratio) of polysaccharide A to polysaccharide B is preferably 99:1 to 50:50, more preferably 98:2 to 55:45, further preferably 95:5 to 60:40, 93:7 to 70:30, or 92:8 to 65:35, and even more preferably 91:9 to 70:30. If the content ratio of polysaccharide A to polysaccharide B is within the above range, the mechanical strength and processability can be further improved while maintaining the water solubility of the water-soluble film.

[0077] <Additives>

[0078] In the bag of the present invention, the water-soluble film may contain plasticizers and other additives (also referred to as additive A) other than polysaccharide B, to a extent that does not impair the effects of the present invention. Examples of additive A include dispersants, water, antioxidants, ultraviolet absorbers, lubricants, colorants, preservatives, fillers, surfactants, anti-blocking agents, release agents, pigments, crosslinking agents, etc. Additive A may be used alone or in combination of two or more. It should be noted that in this specification, plasticizers, polysaccharide B, and additive A are sometimes collectively referred to as "additives".

[0079] The filler refers to a component incompatible with polysaccharide A. In a bag, if the water-soluble film contains a filler, a higher-order network can be formed through hydrogen bonding with polysaccharide A, thus significantly improving the stress of the resulting bag. Furthermore, particularly in the case of producing a water-soluble film by coating, adding a filler to the coating agent increases the concentration of solid components, thereby increasing the thickness of the coating film.

[0080] Examples of fillers include kaolin, clay, engineered kaolin, segregated clay, heavy calcium carbonate, light calcium carbonate, mica (expandable mica, synthetic mica, muscovite, sericite, phlogopite, biotite, fluorophlogopite (artificial mica), ruby, sodium mica, vanadium mica, illite, titaniamica, sodium mica, brittle mica, etc.), talc, titanium dioxide, barium sulfate, calcium sulfate, zinc oxide, silica, silicates, bentonite (montmorillonite, bedecitex, saponite, magnesia, lithium montmorillonite, etc.), colloidal silica, and satin white inorganic pigments, as well as dense, hollow, or core-shell organic pigments. A single filler can be used, or two or more can be used in combination.

[0081] In the case where the water-soluble film contains fillers in the bag, from the viewpoint of increasing the stress of the obtained bag, the total content of fillers relative to the mass of the water-soluble film is preferably 0.1 to 50% by mass, more preferably 0.5 to 35% by mass, even more preferably 1 to 30% by mass, even more preferably 1.5 to 20% by mass, even more preferably 2 to 18% by mass, even more preferably 2 to 15% by mass, even more preferably 2 to 10% by mass, and particularly preferably 2 to 6% by mass. Furthermore, from the viewpoint of increasing the thickness of the coating film, the total content of fillers relative to the mass of the water-soluble film is preferably 1 to 90% by mass, more preferably 5 to 80% by mass, even more preferably 10 to 75% by mass, even more preferably 20 to 70% by mass, even more preferably 30 to 65% by mass, even more preferably 40 to 60% by mass, even more preferably 42 to 58% by mass, and particularly preferably 45 to 55% by mass.

[0082] Alternatively, a dispersant can be added to the coating agent used to make the water-soluble film in the bag. By adding a dispersant, the dispersibility of the filler can be improved.

[0083] As a dispersant, cationic polymers are preferred, such as polyalkylene polyamines, polyamide compounds, polyamide amine-epimergic alcohol or formaldehyde condensation products, polyamine-epimergic alcohol or formaldehyde condensation products, polyamide-polyurea-epimergic alcohol or formaldehyde condensation products, polyamine-polyurea-epimergic alcohol or formaldehyde condensation products, polyamide-polyurea-epimergic alcohol or formaldehyde condensation products, polyamide-polyurea compounds, polyamine-polyurea compounds, polyamide-amine-polyurea compounds and polyamide-amine compounds, polyethyleneimine, polyvinylpyridine, amino-modified acrylamide compounds, polyethyleneamine, polydiallyldimethylammonium chloride, and modified polyvinyl alcohol. A single dispersant can be used, or two or more can be used in combination.

[0084] In the bag, when the water-soluble film contains a dispersant, the content of the dispersant is preferably 0.01 to 20% by mass, more preferably 0.1 to 10% by mass, and even more preferably 1 to 5% by mass, relative to the mass of the water-soluble film.

[0085] Examples of cross-linking agents include tannic acid and its salts, tannins other than tannic acid, catechins, anthocyanins, gallic acid and its salts, phenols, hydroquinone, etc.

[0086] The content of additive A is not particularly limited as long as it does not impair the effect of the present invention. Relative to the mass of the water-soluble film, it is, for example, about 0 to about 10% by mass, preferably about 0.001% to about 10% by mass, more preferably about 0.01% to about 5% by mass, and even more preferably about 0.1% to about 1% by mass.

[0087] In one embodiment of the present invention, in the bag of the present invention, the content of polyvinyl alcohol resin in the water-soluble film is preferably less than 30% by mass, more preferably less than 20% by mass, further preferably less than 10% by mass, more preferably less than 5% by mass, particularly preferably less than 1% by mass, particularly more preferably 0.1% by mass, and may also be 0% by mass. That is, preferably 0 to less than 30% by mass, more preferably 0 to 20% by mass, more preferably 0 to 10% by mass, more preferably 0 to 5% by mass, particularly preferably 0 to 1% by mass, and particularly more preferably 0 to 0.1% by mass. The polyvinyl alcohol resin used in the present invention may use vinyl acetate containing carbon derived from petroleum, vinyl acetate containing carbon derived from biomass, or a mixture thereof as raw material. Alternatively, a polyvinyl alcohol resin in which the apparent biomass ratio has been changed through a mass balance method may also be used.

[0088] In one embodiment of the present invention, in the bag of the present invention, the total content of polysaccharide A, plasticizer, and polysaccharide B contained in the water-soluble film, relative to the mass of the water-soluble film, is preferably 30% by mass or more, more preferably 50% by mass or more, further preferably 70% by mass or more, further more preferably 80% by mass or more, particularly preferably 90% by mass or more, particularly more preferably 95% by mass or more, particularly more preferably 98% by mass or more, and may also be 100% by mass. That is, preferably 30 to 100% by mass, more preferably 50 to 100% by mass, further preferably 70 to 100% by mass, further more preferably 80 to 100% by mass, particularly preferably 90 to 100% by mass, particularly more preferably 95 to 100% by mass, and particularly more preferably 98 to 100% by mass. If the total content of polysaccharide A, plasticizer, and polysaccharide B contained in the water-soluble film is within the above range, the solubility and mechanical strength of the bag at low temperatures can be further improved. It should be noted that the above total content also includes the case where the plasticizer and / or polysaccharide B is 0% by mass.

[0089] <Water-soluble membrane>

[0090] The bag of the present invention comprises a water-soluble membrane. In the present invention, water solubility means being soluble in water, preferably meaning a solubility of 90% by mass or more in warm water at 90°C. That is, if, after adding the water-soluble membrane to warm water at 90°C and stirring for 5 minutes to dissolve the membrane, the amount of solid components that do not pass through a filter (21 μm) is less than 10% by mass, it can be evaluated as water-soluble. It should be noted that the mass of the water-soluble membrane dissolved in warm water at 90°C is 0.1 parts by mass relative to 100 parts by mass of warm water at 90°C. If the solubility of the water-soluble membrane in warm water at 90°C is 90% by mass or more, preferably 95% by mass or more, and more preferably 98% by mass or more, then residue is less likely to remain when using a bag containing this membrane. It should be noted that the upper limit of the solubility of the water-soluble membrane is 100% by mass. That is, the solubility of the water-soluble membrane is 90–100% by mass, preferably 95–100% by mass, and more preferably 98–100% by mass. The solubility of a water-soluble membrane can be adjusted to be above the lower limit mentioned above by appropriately adjusting, for example, the type and / or amount of the components (e.g., additives) contained in the water-soluble membrane.

[0091] In one embodiment of the invention, the water-soluble membrane preferably dissolves in water at 10°C within 1000 seconds. That is, when a water-soluble membrane with a length of 30 mm × width of 40 mm × thickness of 50 μm is immersed in 500 mL of water at 10°C, the time required for complete dissolution is preferably within 1000 seconds, more preferably within 700 seconds, further preferably within 600 seconds, and even more preferably within 500 seconds. For example, it can also be within 300 seconds or 180 seconds. If the time for complete dissolution of the water-soluble membrane in water at 10°C is below the above-mentioned upper limit, the contents can be released quickly when the bag containing the membrane is specifically dissolved in cold water for use, which is therefore preferable. In addition, it is less likely to leave residue. It should be noted that there is no particular limitation on the lower limit of the complete dissolution time, but the shorter the time required for complete dissolution, the better. The complete dissolution time of the water-soluble membrane in water at 10°C can be adjusted to below the aforementioned upper limit by appropriately adjusting, for example, the type and / or amount of components contained in the water-soluble membrane; the manufacturing conditions of the water-soluble membrane (drying conditions, etc.). The complete dissolution time in water at 10°C can be determined, for example, by the method described in the examples described later.

[0092] The thickness of the water-soluble membrane is preferably 1–500 μm, more preferably 5–300 μm, and even more preferably 10–100 μm. If the thickness of the water-soluble membrane is within the above range, the bag exhibits good solubility and mechanical strength at low temperatures. The thickness of the water-soluble membrane can be determined, for example, using a thickness gauge, or by the method described in the examples below.

[0093] The maximum stress of the water-soluble film is preferably 5 MPa or more, more preferably 10 MPa or more, even more preferably 20 MPa or more, even more preferably 25 MPa or more, and particularly preferably 30 MPa or more, for example, 35 MPa, 40 MPa, 45 MPa or 50 MPa or more. If the maximum stress of the water-soluble film is above the above lower limit, the mechanical strength of the bag containing the water-soluble film can be improved. The upper limit of the maximum stress of the water-soluble film is usually 150 MPa or less, preferably 140 MPa or less. That is, the preferred range is 5-150 MPa, 10-150 MPa, 20-150 MPa, 25-150 MPa, 30-150 MPa, 35-150 MPa, 40-150 MPa, 45-150 MPa or 50-140 MPa. The maximum stress of a water-soluble membrane can be adjusted to be above the lower limit mentioned above by appropriate adjustments, such as the type and / or amount of the components contained in the water-soluble membrane, and the manufacturing conditions of the water-soluble membrane (e.g., drying temperature and / or time).

[0094] The elongation at break of the water-soluble film is preferably 10% or more, more preferably 25% or more, further preferably 35% or more, even more preferably 40% or more, particularly preferably 50% or more, even more preferably 70% or more, even more preferably 75% or more, and most preferably 80% or more or 85% or more. If the elongation at break of the water-soluble film is above the lower limit mentioned above, the mechanical strength of the bag containing the water-soluble film can be improved. The upper limit of the elongation at break of the water-soluble film is generally 150% or less, preferably 140% or less. That is, the preferred range is 10–150%, 25–150%, 35–150%, 40–150%, 50–150%, 70–150%, 75–150%, 80–150%, or 85–140%. The elongation at break of the water-soluble membrane can be adjusted to be above the aforementioned lower limit by appropriately adjusting, for example, the type and / or amount of components contained in the water-soluble membrane; the manufacturing conditions of the water-soluble membrane (e.g., drying temperature and / or time), etc. The maximum stress and elongation at break of the water-soluble membrane can be determined by tensile testing, for example, by the method described in the examples below.

[0095] The toughness value of the water-soluble film is preferably 400 or higher, more preferably 900 or higher, even more preferably 1100 or higher, even more preferably 1200 or higher, particularly preferably 1300 or higher, even more preferably 1400 or higher, even more preferably 1500 or higher, and extremely preferably 1600 or higher. For example, it can be 1700 or higher, 1800 or higher, 1900 or higher, or 2000 or higher. If the toughness value of the water-soluble film is above the lower limit mentioned above, the mechanical strength of the bag containing the water-soluble film can be improved. It should be noted that the upper limit of the toughness value is usually 3000 or lower. That is, the preferred ranges are 400–3000, 900–3000, 1100–3000, 1200–3000, 1300–3000, 1400–3000, 1500–3000, 1600–3000, 1700–3000, 1800–3000, 1900–3000, or 2000–3000. The toughness value of the water-soluble film can be determined by multiplying the maximum stress by the elongation at break in a tensile test.

[0096] In one embodiment of the present invention, the water-soluble film does not leach plasticizer and exhibits excellent homogeneity. The surface of the water-soluble film can be flat, and from the viewpoint of preventing products from sticking together, embossing, raised or recessed patterns, or other textured processing can be applied to one or both sides of the water-soluble film. This textured processing can be performed using methods known in the art.

[0097] <Method for manufacturing water-soluble membranes>

[0098] The method for manufacturing the water-soluble film used in the bag of the present invention is not particularly limited, and can be manufactured by methods known in the art.

[0099] Water-soluble membranes can be manufactured, for example, by a method including the following steps: (1) A process of obtaining a coating liquid (coating agent) by stirring at a specified temperature at which at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and their derivatives, a solvent, and additives as required. (2) The process of forming a coating film; and (3) The process of drying the above coating to form a dry coating.

[0100] The solids concentration of the coating solution is preferably 1 to 15% by mass, more preferably 2 to 10% by mass. The solids concentration represents the total mass of components other than the solvent (e.g., polysaccharide A, additives, etc.) relative to the mass of the coating solution.

[0101] The temperature for stirring polysaccharide A, along with any necessary additives and solvents, is typically 15–100°C, preferably 30–98°C. The stirring method is not particularly limited and can be performed using conventionally known methods.

[0102] There are no particular limitations on the solvent, but water, ethanol, methanol, 1-propanol, 2-propanol, etc. are preferred from the perspective of easy dissolution of polysaccharide A and easy drying afterwards.

[0103] The coating can be formed, for example, by applying a coating liquid onto a substrate. Examples of substrates include polyolefins such as polyethylene and polypropylene; polyesters such as polyethylene terephthalate; polyamides such as nylon 6 and nylon 66; fluoropolymers such as Teflon; and metal sheets.

[0104] Methods for applying coating liquid to substrates include known methods such as spin coating, extrusion coating, bar coating, and coater coating. Coating machines can be various types, including doctor blade coaters, bar coaters, roller coaters, gravure coaters, reverse gravure coaters, comma coaters, air knife coaters, reverse roller coaters, curtain coaters, spray coaters, sizing press coaters, and guillotine coaters.

[0105] Next, the solvent is removed by drying to form a dry coating film. Examples of drying methods include natural drying, ventilation drying, heating drying, and reduced pressure drying. Examples of dryers include conventional dryers such as steam heaters, gas heaters, infrared heaters, electric heaters, hot air heaters, microwave dryers, and cylinder dryers.

[0106] The above-mentioned dried coating is a water-soluble film.

[0107] Alternatively, water-soluble films can be manufactured by melt extrusion film forming method or blow molding method, which uses a film-forming solution obtained by an extruder or the like to extrude it from a T-die or the like.

[0108] It should be noted that after forming a water-soluble film on the substrate, removing the substrate yields the water-soluble film. Alternatively, it can be used directly in this state without peeling off the substrate. Without peeling off the substrate, a laminate comprising the substrate (support) and the water-soluble film can be obtained. If the substrate is peeled off, it is preferable to apply a release agent to the coated surface.

[0109] [Layered Body]

[0110] The present invention also includes a laminate comprising a water-soluble film containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and their derivatives, and a support. The support is preferably paper or a film. The laminate of the present invention in this embodiment contains a specific polysaccharide A, thus exhibiting excellent solubility and mechanical strength at low temperatures.

[0111] Examples of supports in a laminate comprising a water-soluble membrane and a support include paper or membrane (hereinafter also referred to as "support membrane").

[0112] When the support is paper, examples of such paper include kraft paper, single-sided kraft paper, single-sided bleached kraft paper, bleached kraft paper, unbleached kraft paper, high-quality paper, medium-quality paper, coated paper, single-sided paper, molded paper, glassine paper, high-transparency glassine paper, parchment, synthetic paper, whiteboard paper, Manila paper, milk carton base paper, cup base paper, ivory paper, silver paper, tissue paper, board paper, rayon paper, waxed paper, padding paper, etc.

[0113] From the viewpoint of suitability for packaging applications, the preferred basis weight of the paper is 20–400 g / m³. 2 More preferably 25–150 g / m 2 From the viewpoint of suitability for the flexible packaging material applications described later, the preferred basis weight of the paper is 30–100 g / m³. 2 Further preferred is 40–70 g / m 2 The basis weight of the paper was determined according to JIS P 8124:2011.

[0114] The aforementioned paper can typically be manufactured by papermaking of paper stock containing pulp, fillers, and various additives.

[0115] Examples of pulps include chemical pulps such as bleached sulfate hardwood pulp (LBKP), bleached sulfate softwood pulp (NBKP), unbleached sulfate hardwood pulp (LUKP), unbleached softwood pulp (NUKP), and sulfite pulp; mechanical pulps such as stone mill pulp and thermomechanical pulp; wood fibers such as deinked pulp and recycled paper pulp; and non-wood fibers such as flax, bamboo, and hemp. These can be used alone or in combination of two or more. Among these, from the viewpoint of reducing the possibility of foreign matter contamination into the base paper and the possibility of discoloration over time during recycling, achieving good printability with high whiteness, and improving the use value (especially when used as packaging material), chemical pulps and mechanical pulps made of wood fibers are preferred, with chemical pulps being more preferred.

[0116] Provided it does not impair the effectiveness of this invention, it can also be used as a secondary paper material in combination with materials other than pulp. Examples of such materials include synthetic fibers such as rayon fibers and nylon fibers.

[0117] Examples of fillers include silica, talc, kaolin, clay, heavy calcium carbonate, light calcium carbonate, titanium dioxide, zeolite, and synthetic resin fillers. They can be used alone or in combination of two or more.

[0118] Examples of various additives include aluminum sulfate, various anionic, cationic, nonionic, or amphoteric yield improvers, water permeability improvers, paper strength enhancers, and internal sizing agents, which can be used alone or in combination of two or more. Dyes, fluorescent whitening agents, pH adjusters, defoamers, resin control agents, slime control agents, and two or more of these additives can also be used optionally.

[0119] There are no particular limitations on the method of paper manufacturing; for example, paper can be manufactured by following these steps.

[0120] First, paper stock is prepared by mixing pulp, fillers, and various additives. The pulp can be prepared by beating the pulp in the presence of water. There are no particular limitations on the beating method and apparatus; well-known beating methods and apparatus can be used. The pulp content in the paper stock is not particularly limited. For example, it may be 60% by mass or more but less than 100% by mass relative to the total mass of the paper stock.

[0121] Next, using known wire forming machines, multi-wire forming machines, and clamp forming machines, the prepared paper stock is processed using acidic, neutral, or alkaline papermaking methods. The dehydrated wet paper is then stacked multiple times as needed, and one or more sheets are pressed and dried to obtain paper. At this point, without stacking multiple sheets, a single-layer paper is obtained; with stacked sheets, a multi-layer paper is obtained. When stacking multiple sheets, an adhesive can be applied to the surface of the wet paper (the side overlapping the other sheets).

[0122] Paper can be surface-treated using various agents. Examples of agents that can be used include oxidized starch, hydroxyethyl etherified starch, enzyme-modified starch, polyacrylamide, polyvinyl alcohol, surface sizing agents, water-resistant agents, water-retaining agents, thickeners, and lubricants. These can be used alone or in combination of two or more. Furthermore, these various agents and pigments can be used together. Examples of pigments include inorganic pigments such as kaolin, clay, engineered kaolin, layered clay, heavy calcium carbonate, light calcium carbonate, mica, talc, titanium dioxide, barium sulfate, calcium sulfate, zinc oxide, silicic acid, silicates, colloidal silica, and satin white, as well as organic pigments such as dense, hollow, or core-shell types. These can be used alone or in combination of two or more.

[0123] There are no particular limitations on the surface treatment methods for paper. For example, it can be treated using known coating equipment such as rod metering sizepress, pond sizepress, roll coater, sprayer, scraper coater, and curtain coater.

[0124] When the support is a membrane, examples of such membranes include (polyolefin membranes such as polyethylene, polypropylene and norbornene polymers; polyvinyl alcohol membranes; polyethylene terephthalate (PET) membranes; poly(meth)acrylate membranes; cellulose ester membranes such as triacetyl cellulose, diacetyl cellulose and cellulose acetate propionate; polylactic acid membranes; ethylene-vinyl alcohol copolymer membranes, etc.), sheets, etc.

[0125] The average thickness of the paper or film used as a support is, for example, about 1 μm to about 500 μm or about 10 μm to about 300 μm.

[0126] In a laminate, the water-soluble film can be a single layer or multiple layers. When the water-soluble film is multiple layers, the layers can be identical or different. Furthermore, the laminate can include optional layers. The laminate can have one or more layers selected from the group consisting of a barrier layer, a protective layer, and a heat-sealing layer at any position in its layer structure. When the laminate has a protective layer and / or a heat-sealing layer, this layer is preferably disposed on the outermost layer of the laminate.

[0127] The barrier layer can be a gas barrier layer or a water vapor barrier layer, and such barrier layers are known in the art. Examples of barrier layers include resin layers and metal foils. More specific examples include resin layers containing polyvinyl alcohol, ethylene-vinyl alcohol copolymers and / or polyvinylidene chloride, layers containing polysaccharide A but not equivalent to the water-soluble film of the present invention, aluminum foil, aluminum vapor-deposited films (films formed by vapor-depositing aluminum on substrates such as polyethylene, polypropylene, nylon, polyethylene terephthalate, and ethylene-vinyl alcohol copolymers), alumina vapor-deposited films (films formed by vapor-depositing alumina on substrates such as polyethylene, polypropylene, nylon, polyethylene terephthalate, and ethylene-vinyl alcohol copolymers), and silica vapor-deposited films (films formed by vapor-depositing silica on substrates such as polyethylene, polypropylene, nylon, polyethylene terephthalate, and ethylene-vinyl alcohol copolymers).

[0128] A protective layer is a layer that reduces the impact of the surrounding environment on the constituent elements existing below the protective layer (deterioration of the constituent elements) by existing as at least a portion of the outermost layer of the aforementioned laminate. Therefore, the protective layer can possess one or more functions selected from the group consisting of barrier properties, oil resistance, solvent resistance, heat resistance, abrasion resistance, impact resistance, weather resistance, and light resistance. By covering the entire outermost layer of the aforementioned laminate with a protective layer, the aforementioned functions can be achieved. Examples of protective layers include resin layers, paper layers, and metal foils.

[0129] As a heat-sealing layer, heat-sealing layers known in this art can be used. The heat-sealing layer is preferably a resin layer with heat-sealing properties. The heat-sealing layer preferably contains a water-dispersible resin and optional additives. Examples of water-dispersible resins include polyolefin resins, styrene / acrylic copolymers, acrylic resins such as ethylene-(meth)acrylic acid copolymers, ethylene-vinyl acetate copolymers, polyester resins, rubber-based resins, polyurethane resins, polyamide resins, and combinations thereof. Examples of optional additives include lubricants such as paraffin wax, carnauba wax, and polyolefin waxes, pigments such as silica and kaolin, and combinations thereof. The heat-sealing layer may also have barrier properties; in this case, the layer can function as both a heat-sealing layer and a barrier layer.

[0130] When the support is a membrane with barrier or protective properties, the membrane can also function as a barrier layer or a protective layer.

[0131] As a specific layer configuration of the laminate of the present invention, which includes a water-soluble film and a support and may have optional layers (barrier layer, protective layer, heat-sealing layer), examples can be listed below. It should be noted that the following configurations are described starting from the layer that, for example, becomes the outermost layer (the layer opposite to the layer in contact with the contents) when used as a packaging material.

[0132] Water-soluble membrane / paper or support membrane or metal foil, Gas barrier layer or water vapor barrier layer / water-soluble film / paper or support film or metal foil, Water vapor barrier layer / gas barrier layer / water-soluble film / paper or support film or metal foil Gas barrier layer / water vapor barrier layer / water-soluble film / paper or support film or metal foil Protective layer / water-soluble film / paper or support film or metal foil, Protective layer / gas barrier layer or water vapor barrier layer / water-soluble film / paper or support film or metal foil, Protective layer / water vapor barrier layer / gas barrier layer / water-soluble film / paper or support film or metal foil, Protective layer / gas barrier layer / water vapor barrier layer / water-soluble film / paper or support film or metal foil, Protective layer / water-soluble film / gas barrier layer or water vapor barrier layer / paper or support film or metal foil, Protective layer / water-soluble film / water vapor barrier layer / gas barrier layer / paper or support film or metal foil, Protective layer / water-soluble film / gas barrier layer / water vapor barrier layer / paper or support film or metal foil, Protective layer / gas barrier layer or water vapor barrier layer / water-soluble film / paper or support film or metal foil / gas barrier layer or water vapor barrier layer Protective layer / water vapor barrier layer / gas barrier layer / water-soluble film / paper or support film or metal foil / gas barrier layer or water vapor barrier layer Protective layer / gas barrier layer / water vapor barrier layer / water-soluble film / paper or support film or metal foil / gas barrier layer or water vapor barrier layer Protective layer / water vapor barrier layer / gas barrier layer / water-soluble film / paper or support film or metal foil / gas barrier layer / water vapor barrier layer Protective layer / water vapor barrier layer / gas barrier layer / water-soluble film / paper or support film or metal foil / water vapor barrier layer / gas barrier layer Protective layer / Gas barrier layer / Water vapor barrier layer / Water-soluble film / Paper or support film or metal foil / Gas barrier layer / Water vapor barrier layer Protective layer / Gas barrier layer / Water vapor barrier layer / Water-soluble film / Paper or support film or metal foil / Water vapor barrier layer / Gas barrier layer A layer configuration in which a heat-sealing layer is provided on the opposite side of the outermost layer in the above-mentioned layer configuration. A layer configuration that replaces the protective layer in the above-mentioned layer configuration, such as a heat-sealing layer / water-soluble film / paper or support film or metal foil. The above-mentioned layer configuration includes a layer configuration in which one or more adhesive layers are provided between the layers, such as heat-sealing layer / adhesive layer / water-soluble film / paper or support film or metal foil.

[0133] As a more specific layered structure, for example, the structure described below can be listed.

[0134] Water-soluble film / paper

[0135] LLDPE / water-soluble film / paper LLDPE / adhesive layer / water-soluble film / paper LDPE / water-soluble film / paper LDPE / adhesive layer / water-soluble film / paper HDPE / water-soluble film / paper HDPE / adhesive layer / water-soluble film / paper CPE (unstretched polyethylene) / water-soluble film / paper CPE (unstretched polyethylene) / adhesive layer / water-soluble film / paper Polyethylene / water-soluble film / paper formed from polyethylene emulsion Polyethylene / adhesive layer / water-soluble film / paper formed from polyethylene emulsion Uniaxially stretched polyethylene / water-soluble film / paper Uniaxially stretched polyethylene / adhesive layer / water-soluble film / paper Biaxially stretched polyethylene / water-soluble film / paper Biaxially stretched polyethylene / adhesive layer / water-soluble film / paper Polypropylene / water-soluble film / paper Polypropylene / adhesive layer / water-soluble film / paper Uniaxially stretched polypropylene / water-soluble film / paper Uniaxially stretched polypropylene / adhesive layer / water-soluble film / paper Biaxially stretched polypropylene / water-soluble film / paper Biaxially oriented polypropylene / adhesive layer / water-soluble film / paper PLA / water-soluble film / paper PLA / adhesive layer / water-soluble film / paper PHA / water-soluble membrane / paper PHA / adhesive layer / water-soluble film / paper PHBH / water-soluble film / paper PHBH / Adhesive Layer / Water-soluble Film / Paper PCL / water-soluble film / paper PCL / adhesive layer / water-soluble film / paper PBAT / water-soluble film / paper PBAT / adhesive layer / water-soluble film / paper PBS / water-soluble membrane / paper PBS / adhesive layer / water-soluble membrane / paper.

[0136] <Method for manufacturing laminates>

[0137] The method for manufacturing the laminate of the present invention is not particularly limited, and can be manufactured by methods known in the art.

[0138] The laminate of the present invention can be manufactured, for example, by a method including the same steps (1) to (3) described in the method for manufacturing the water-soluble film described above. In the laminate, the coating film can be a single layer or multiple layers. A multilayer laminate containing optional layers in an optional stacking order can also be manufactured by repeatedly applying a coating liquid (coating agent) to a support and removing the solvent.

[0139] Furthermore, the laminate of the present invention can be manufactured, for example, by integrating a water-soluble film with a support. The water-soluble film is manufactured by melt extrusion molding or blow molding, whereby a film-forming stock solution (water-soluble film-forming material) obtained using an extruder or the like is extruded from a T-die. The method of integration is not limited; examples include methods such as coating the surface of the water-soluble film with water and bonding the coated surface to the support, integrating the water-soluble film and the support by hot pressing, integrating the water-soluble film and the support via an adhesive or bonding agent, and blow molding by co-extruding the water-soluble film-forming material and the material forming the support (film).

[0140] When integration is achieved through hot pressing, the conditions can be appropriately selected based on the type of polysaccharides contained in the water-soluble film and the type and amount of plasticizers present. For example, integration can be achieved by pressing at a temperature of 100–200°C and a pressure of 0.1–30 MPa for 0.1–10 seconds.

[0141] In cases of integration via adhesives or bonding agents, such adhesives or bonding agents are known in the art.

[0142] The laminate of the present invention can also be manufactured by attaching multiple water-soluble films obtained by melt extrusion film forming or blow molding to a support using known methods.

[0143] In the case where the laminate contains multiple water-soluble films, it is possible to combine water-soluble films manufactured by coating and water-soluble films manufactured by melt extrusion or blow molding, etc.

[0144] <Bag>

[0145] The bag of the present invention comprises the aforementioned water-soluble film, thus exhibiting excellent solubility and mechanical strength at low temperatures. Therefore, the bag of the present invention preferably dissolves in water at 10°C within 2000 seconds, more preferably within 1500 seconds, further preferably within 1000 seconds, even more preferably within 700 seconds, particularly preferably within 600 seconds, and particularly more preferably within 500 seconds. There is no particular limitation on the lower limit of the dissolution time, but a shorter dissolution time is preferred. The solubility of the bag in water at 10°C can be adjusted to the aforementioned lower limit or above by appropriately adjusting, for example, the type and / or amount of components (e.g., additives) contained in the water-soluble film constituting the bag; the manufacturing conditions of the bag (e.g., the amount of water applied, temperature, and pressure during water sealing; the temperature and pressure during heat sealing), etc. The solubility of the bag in water at 10°C can be determined, for example, by the method described in the examples described later.

[0146] The bag may contain a single-layer film or a multi-layer film. When the bag is composed of a single-layer film (or a single-layer film), the single-layer film is the aforementioned water-soluble film. When the bag is composed of a multi-layer film (or a multi-layer film), the multi-layer film may be a stack of multiple aforementioned water-soluble films, or a stack of the aforementioned water-soluble film with other water-soluble films besides the aforementioned water-soluble film. From the viewpoint of improving the bag's solubility and mechanical strength at low temperatures, the bag is preferably composed of a single-layer or multi-layer water-soluble film; further considering manufacturing efficiency, a single-layer water-soluble film is more preferable.

[0147] The bag of the present invention has excellent mechanical strength, and its compressive strength is preferably 50 N or more, more preferably 100 N or more, further preferably 200 N or more, even more preferably 300 N or more, and particularly preferably 400 N or more. For example, it can be 500 N, 600 N, 700 N, or 800 N or more. The upper limit of the compressive strength of the bag is generally 2000 N or less, preferably 1000 N or less. That is, the preferred range is 50–2000 N, 100–2000 N, 200–2000 N, 300–2000 N, 400–2000 N, 500–2000 N, 600–2000 N, 700–2000 N, or 800–1000 N. The compressive strength of the bag can be adjusted to be above the lower limit by appropriate adjustments, such as the type and / or amount of components contained in the water-soluble film constituting the bag; the manufacturing conditions of the water-soluble film (e.g., drying temperature and / or time); the manufacturing conditions of the bag (e.g., the amount, temperature, and pressure of water coating during water sealing; the temperature and pressure during heat sealing).

[0148] The form of the bag is not particularly limited as long as it can package substances (preferably contents). It can be a bag that is sealed inside or a bag that is partially open. Although there is no limitation, the bag can be, for example, a two-side sealed bag, a three-side sealed bag, a flat bag, a stand-up pouch, a corner-supported bag, a bottom-supported bag, a double-sided bag, a spout bag, a side-sealed bag, a bottom-sealed bag, etc., and can also be a container, a cup, etc. In one embodiment of the present invention, the bag can be a partially open bag, but it is preferred to be a bag that is sealed inside. In this embodiment, it is more preferred that the bag contains contents inside and that the inside is sealed.

[0149] [Bag manufacturing method]

[0150] There are no particular limitations on the method for manufacturing the bag of the present invention from the water-soluble film, and it can be manufactured by methods known in the art.

[0151] The bag of the present invention can be manufactured, for example, by a method including a step of sealing one or more water-soluble films to form a bag shape. Alternatively, the bag containing contents can be manufactured, for example, by a method including a step of placing the contents into a film formed into a bag shape and a step of sealing the opening; a step of forming a recess in a first film, a step of placing the contents into the recess, and a step of attaching a second film and sealing it, etc.

[0152] Methods for sealing water-soluble membranes include sealing by bonding the coated surface with water (also known as water sealing), sealing by heat pressing (also known as heat sealing), and sealing by using adhesives.

[0153] From the perspective of minimizing thermal degradation of the membrane, a water seal is preferred.

[0154] In one embodiment of the invention, the water-soluble film possesses high adhesive strength due to moisture, thus enabling suitable use of a water seal. Furthermore, in another embodiment of the invention, the water-soluble film exhibits high water-sealing properties and low heat-sealing properties. Due to the low heat-sealing properties, when the film is manufactured in a roll-to-roll manner, the film is less likely to adhere tightly to the rollers, effectively suppressing damage during manufacturing. Moreover, due to the high water-sealing properties, the manufactured water-soluble film can be easily and readily formed into bags using moisture.

[0155] [Uses of the bag]

[0156] The bags of the present invention exhibit excellent solubility and mechanical strength at low temperatures, making them particularly suitable for applications where they are dissolved in cold water. Therefore, the bags of the present invention preferably contain at least one ingredient selected from the group consisting of detergents, fabric softeners, and fragrances. The physical properties of the contents are not particularly limited and can be acidic, neutral, or alkaline. Furthermore, the form of the contents can be any of powder, block, gel, or liquid.

[0157] [Water-soluble membrane]

[0158] The present invention also includes a water-soluble film containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and their derivatives. The water-soluble film of the present invention in this embodiment contains a specific polysaccharide A, thus exhibiting excellent solubility and mechanical strength at low temperatures, and is capable of forming bags with such properties. This water-soluble film is identical to the water-soluble film described in the [bag] section above.

[0159] The present invention also includes a water-soluble film containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and their derivatives, and a polysaccharide B different from the aforementioned polysaccharide A. The water-soluble film of the present invention in this embodiment contains specific polysaccharides A and B, thus exhibiting excellent solubility and mechanical strength at low temperatures, and is capable of forming bags with such properties. Preferably, this water-soluble film is identical to the water-soluble film described in the [bag] section above, except that it contains polysaccharide B as an essential component in addition to polysaccharide A.

[0160] Furthermore, the present invention also includes a water-soluble film for use in bags, comprising at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and their derivatives, and a plasticizer, wherein the content of the plasticizer is 45% by mass or less relative to the mass of the water-soluble film. The water-soluble film of the present invention in this embodiment contains at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and their derivatives, thus exhibiting excellent solubility and mechanical strength at low temperatures, and enabling the formation of bags with such properties. Furthermore, the water-soluble film is less prone to plasticizer exudation on its surface. Preferably, this water-soluble film is the same as the water-soluble film described in the [bag] section above, except that it must contain at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and their derivatives, and a plasticizer, with the plasticizer content being 45% by mass or less.

[0161] From the viewpoint that plasticizers are less likely to leach from the membrane surface, the plasticizer content is preferably 40% by mass or less, more preferably 35% by mass or less, and even more preferably 30% by mass or less, relative to the mass of the water-soluble membrane. The lower limit of the plasticizer content is generally 1% by mass or more, more preferably 3% by mass or more, and even more preferably 5% by mass or more. Therefore, the preferred range is 1–40% by mass, 3–35% by mass, or 5–30% by mass.

[0162] Packaging materials

[0163] The present invention also includes a packaging material comprising a water-soluble film containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and their derivatives. The packaging material of the present invention in this embodiment contains a specific polysaccharide A, and therefore exhibits excellent solubility and mechanical strength at low temperatures. The water-soluble film constituting this packaging material is preferably the same as the water-soluble film described in the [bag] section above, and preferably has the same solubility and mechanical strength. Furthermore, this packaging material preferably has the same solubility and mechanical strength as the bag described in the [bag] section above.

[0164] Packaging material is a film used for packaging, which may include thin films, thick films, etc., and may also take the form of containers, cups, tubes, trays, bottles, etc. In one embodiment of the present invention, the packaging material may contain a substance inside, similar to the bag described above, preferably at least one selected from the group consisting of detergents, fabric softeners, and fragrances.

[0165] Example

[0166] The present invention will now be described in more detail based on embodiments and comparative examples, but the present invention is not limited to the following embodiments.

[0167] Molecular weight of polysaccharides

[0168] For the polysaccharides used in the examples and comparative examples, approximately 20 μg was administered to gel filtration HPLC under the conditions described below to determine the weight-average molecular weight (Mw) and number-average molecular weight (Mn). It should be noted that, regarding the solvent, water or dimethyl sulfoxide (DMSO) was selected based on the solubility of each polysaccharide.

[0169] (Gel filtration HPLC conditions)

[0170] Eluent: 0.1M Na nitrate aqueous solution

[0171] Column: Use one TSK GEL α-M

[0172] Column temperature: 40℃

[0173] Flow rate: 1 mL / min

[0174] Sample concentration: 0.1 w / v%

[0175] Sample preparation: After dissolving the sample by stirring at 80°C for 2.5 hours, stir at 90°C for 30 minutes.

[0176] Filter: 0.45μm PP filter (Whatman)

[0177] Injection volume: 100 μL

[0178] Standard product: PEO / PEG

[0179] Measurement time: 18 minutes

[0180] Liquid delivery part: GPC-101 (Shodex)

[0181] Detector: RI

[0182] or, Eluent: 5mM Na nitric acid / DMSO Column: Use one TSK GEL α-M Column temperature: 60℃ Flow rate: 0.8 mL / min Sample concentration: 0.2 w / v% Sample preparation: After dissolving the sample by stirring at 60°C for 1 hour, the sample was then stirred at 65°C for 2.5 hours.

[0183] Filtration: 0.45μm PP filter (Whatman)

[0184] Injection volume: 100 μL

[0185] Standard products: PMMA-R, Y, G

[0186] Measurement time: 18 minutes

[0187] Liquid delivery part: GPC-101 (Shodex)

[0188] Detector: RI

[0189] Preparation of water-soluble membranes

[0190] <Example 1>

[0191] 6g of tamarind gum (weight-average molecular weight 3700kDa, number-average molecular weight 429kDa; manufactured by MP GOKYO FOOD & CHEMICAL Co., Ltd., "GLYLOID 6C (registered trademark)") was added to water and heated and stirred at 95°C for 2 hours to obtain a 4% aqueous solution. 4g of glycerol was added to this solution to prepare a coating solution. This coating solution was applied to a polyethylene terephthalate (PET) film using a bar coater and dried with hot air at 60°C for 1 hour. The dried coating was then peeled off from the PET film substrate to obtain a film with a thickness of approximately 50μm.

[0192] <Examples 2-6>

[0193] The amounts of tamarind gum and glycerin were changed to those shown in Table 1, and the membrane was obtained by operating in the same manner as in Example 1.

[0194] <Example 7>

[0195] When adding glycerol, sorbitol was also added in addition to glycerol, and each component was added in the manner shown in Table 1. Otherwise, the same procedure as in Example 1 was followed to obtain the membrane.

[0196] <Examples 8-10>

[0197] When adding glycerol, tannic acid was also added in addition to glycerol, and each component was added in the manner shown in Table 1. Otherwise, the same procedure as in Example 1 was followed to obtain the membrane.

[0198] <Examples 11-14>

[0199] Ethylene glycol was added instead of glycerol, and each component was added in the manner shown in Table 1. Otherwise, the procedure was the same as in Example 1 to obtain the membrane.

[0200] <Examples 15-17>

[0201] Fructose was added instead of glycerol, and each component was added in the manner shown in Table 1. Otherwise, the procedure was the same as in Example 1 to obtain the membrane.

[0202] <Example 18>

[0203] When adding glycerol, xanthan gum (weight-average molecular weight 92kDa, number-average molecular weight 16kDa; manufactured by KIMICA Xanthan PH-R3EC Co., Ltd.) was also added in addition to glycerol, and each component was added in the manner shown in Table 1. Otherwise, the same procedure as in Example 1 was followed to obtain the membrane.

[0204] <Example 19>

[0205] When adding glycerin, guar gum (weight-average molecular weight 93 kDa, number-average molecular weight 17 kDa; manufactured by Sansho Co., Ltd., “SUPERGEL CSA200 / 50”) was also added in addition to glycerin, and each component was added in the manner shown in Table 1. Otherwise, the same procedure as in Example 1 was followed to obtain the membrane.

[0206] <Example 20>

[0207] When adding glycerin, locust bean gum (weight-average molecular weight 96kDa, number-average molecular weight 26kDa; manufactured by Sansho Co., Ltd., “GENU (registered trademark) GUM type RL-200Z”) was also added in addition to glycerin, and each component was added in the manner shown in Table 1. Otherwise, the same procedure as in Example 1 was followed to obtain the membrane.

[0208] <Example 21>

[0209] When adding glycerin, xanthan gum and guar gum were also added in addition to glycerin, and each component was added in the manner shown in Table 1. Otherwise, the same procedure as in Example 1 was followed to obtain the membrane.

[0210] <Example 22>

[0211] When adding glycerol, xanthan gum and locust bean gum were also added in addition to glycerol, in the manner shown in Table 1. Otherwise, the same procedure as in Example 1 was followed to obtain the membrane.

[0212] <Example 23>

[0213] The membrane was obtained by using locust bean gum instead of tamarind gum and glycerol instead of fructose, otherwise the procedure was the same as in Example 17.

[0214] <Comparative Example 1>

[0215] The membrane was obtained by using κ-carrageenan (weight-average molecular weight 826 kDa, number-average molecular weight 48 kDa; manufactured by Sansho Co., Ltd., “GENUGEL carrageenantype JPE-126”) instead of tamarind gum, otherwise the procedure was the same as in Example 3.

[0216] <Comparative Examples 2-4>

[0217] Glycerol was added in the amounts shown in Table 1, and the procedure was otherwise the same as in Comparative Example 1 to obtain the membrane.

[0218] <Comparative Examples 5-6>

[0219] Sorbitol was used instead of glycerin, and each component was added in the manner shown in Table 1. Otherwise, the same procedure as in Comparative Example 1 was followed to obtain the membrane.

[0220] <Comparative Examples 7-8>

[0221] The membrane was obtained by using sodium alginate (weight-average molecular weight 104 kDa, number-average molecular weight 43 kDa; manufactured by KIMICA Co., Ltd., “KIMICA ALGIN I-8”) instead of κ-carrageenan, otherwise the procedure was the same as in Comparative Examples 5 and 6.

[0222] <Comparative Examples 9-10>

[0223] The membrane was obtained by using guar gum (weight-average molecular weight 93 kDa, number-average molecular weight 17 kDa; manufactured by Sansho Co., Ltd., “SUPERGEL CSA200 / 50”) instead of κ-carrageenan, otherwise the procedure was the same as in Comparative Examples 5 and 6.

[0224] <Comparative Example 11>

[0225] The membrane was obtained by using gum arabic (weight-average molecular weight 237 kDa, number-average molecular weight 45 kDa; manufactured by TIC Pretested GumArabic Spray Dry Powder, Ingredion) instead of κ-carrageenan, otherwise the procedure was the same as in Comparative Example 5.

[0226] <Comparative Example 12>

[0227] The membrane was obtained by using gum arabic (weight-average molecular weight 192 kDa, number-average molecular weight 71 kDa; manufactured by TIC Pretested GumArabic FT Ingredion) instead of κ-carrageenan, otherwise the procedure was the same as in Comparative Example 5.

[0228] <Comparative Examples 13-14>

[0229] The membranes were obtained by using cationic modified starch ("CATO304", manufactured by Ingredion) instead of κ-carrageenan, otherwise the procedure was the same as in Comparative Examples 5 and 6.

[0230] <Comparative Example 15>

[0231] Instead of tamarind gum, nonionic modified starch (“National208”, Ingredion) and glycerol were added in the amounts shown in Table 1, and the procedure was otherwise the same as in Example 1 to obtain the membrane.

[0232] <Comparative Examples 16-19>

[0233] Nonionic modified starch (“National208”, Ingredion) and glycerol were added in the amounts shown in Table 1, and the same procedure as in Comparative Example 15 was followed to obtain the membrane.

[0234] <Comparative Example 20>

[0235] The membrane was obtained by using sorbitol instead of glycerol, otherwise the procedure was the same as in Comparative Example 15.

[0236] <Comparative Example 21>

[0237] The membrane was obtained by using sorbitol instead of glycerol, otherwise the procedure was the same as in Comparative Example 17.

[0238] <Comparative Example 22>

[0239] The membrane was obtained by using glycerol instead of sorbitol, otherwise the procedure was the same as in Comparative Examples 9-10.

[0240] <Comparative Examples 23-24>

[0241] The membrane was obtained by using xanthan gum (weight-average molecular weight 92 kDa, number-average molecular weight 16 kDa; "KIMICA Xanthan PH-R3EC", manufactured by KIMICA Co., Ltd.) instead of tamarind gum, otherwise the procedure was the same as in Example 1.

[0242]

[0243] Evaluation of water-soluble membranes

[0244] <Film thickness of water-soluble film>

[0245] The membrane thickness is measured using a micrometer. The thickness is measured at any five or more points, and the average of these measurements is taken as the membrane thickness.

[0246] <Water solubility of membranes>

[0247] The membrane prepared in the examples was added to warm water at 90°C, and after stirring for 5 minutes to dissolve the membrane, the amount of solids that did not pass through the filter (21 μm) was measured. The result was less than 10% by mass in all Examples 1 to 23. It should be noted that the mass of the added membrane was 0.1 parts by mass relative to 100 parts by mass of warm water at 90°C.

[0248] <Complete dissolution time in cold water>

[0249] The membranes prepared in the examples and comparative examples were cut into rectangles of 30mm × 40mm and clipped into a slide holder. Additionally, a 600ml glass beaker containing 500ml of distilled water was placed in a constant temperature bath set to 10°C, and stirred at 400rpm using a 5cm rotor. After the distilled water in the beaker reached 10°C, the slide holder was immersed in the stirred water. The dissolution state of the membrane was visually observed, and the time (in seconds) until the membrane completely dissolved was measured and evaluated according to the following evaluation criteria. It should be noted that when using membranes with a thickness different from 50μm, the value for a 50μm membrane thickness is converted using the following formula.

[0250] Complete dissolution time (seconds) = [50 / film thickness (μm)] 2 × Sample complete dissolution time (seconds)

[0251] Record cases where the calculated complete dissolution time is within 600 seconds as A, and cases where the calculated complete dissolution time exceeds 600 seconds as B.

[0252] <Membrane toughness value>

[0253] After the membranes prepared in the examples and comparative examples were stored at 23°C and 50% RH for 7 days, five test pieces with a width of 10 mm and a length of 120 mm were cut out. For each test piece, the maximum stress and elongation at break were measured using a universal testing machine (device name: AG-5000B, Shimadzu Corporation) under the conditions of a clamping distance of 70 mm and a tensile speed of 500 mm / min, and the average value was calculated. The value of maximum stress × elongation at break was taken as the toughness value of the membrane.

[0254] The evaluation results are shown in Table 2.

[0255]

[0256] Bag making

[0257] <Example 24>

[0258] In the bag forming process, a benchtop bag forming apparatus (manufactured by Dada, DD-SR12-1) was used. The film obtained in Example 1 was cut into two 15×15cm pieces, serving as the bottom film and top film respectively. The bottom film was placed on a bag mold with a bottom surface of 40×45mm and a depth of 18mm. After heating at 100°C for 4 seconds, a vacuum was created between the bottle film and the bag mold, forming the bottom of the bag. Next, water was brushed onto the four sides of the bottom film, and the top film was placed on it, with the four sides of each film overlapping. The overlapping portion of the bottom and top films was heated and compressed at 100°C for 10 seconds to bond the top film to the bottom film. Then, air was injected between the bag mold and the bottom film, and the formed bag was removed from the mold, leaving 1.5cm of the bonded portion. The surrounding film was then cut off and removed.

[0259] <Examples 25-27>

[0260] The bags were obtained by using the membranes obtained in Examples 5, 14, and 23, except that the procedure was the same as in Example 24.

[0261] <Comparative Examples 25-32>

[0262] Bags were obtained by using the membranes obtained in Comparative Examples 1, 11, 12, 14-18, except that the procedure was the same as in Example 24.

[0263] Bag reviews

[0264] <Bottom film condition of the bag>

[0265] Visually evaluate the condition of the bottom film during bottom formation. If the film strength is insufficient, it will break during bottom film formation. Record the case where the film is not broken as A, and the case where the film is broken as B.

[0266] <Air leakage from the bag>

[0267] The obtained bags were placed in an environment of 23°C and 50%RH for 24 hours, and the air leakage of the bags was evaluated. Cases with no air leakage were recorded as A, and cases with air leakage were recorded as B.

[0268] <Water solubility of the bag>

[0269] The obtained bag was used to conduct a water solubility test. The bag was placed in a wire frame cage (10cm × 9cm × 6.4cm, wire gauge 1.25mm, opening 1.27cm). In a 2-liter beaker containing 1200ml of distilled water, the mixture was stirred at 400rpm using a 5cm rotor. After the distilled water in the beaker reached 10°C, the wire frame cage and bag were placed 1 inch (2.54cm) from the bottom of the beaker. The dissolution state of the membrane was visually observed to confirm complete dissolution. The case with no residue was recorded as A, and the case with residue was recorded as B.

[0270] The evaluation results are shown in Table 3.

[0271]

[0272] Creation of stacked bodies

[0273] <Example 28>

[0274] 7g of tamarind gum (Gri-Eit (registered trademark)) and 3g of glycerin were added to pure water at a total concentration of 15% by mass. The mixture was heated and stirred at 90°C for 1 hour to dissolve, yielding a coating solution (coating agent). The coating solution was cooled to 25°C and coated onto a support paper (Solide Lucent 78gsm) using a bar coater to a thickness of 133μm (hereinafter sometimes referred to as "coating thickness"). The wet coating on the support was dried in a hot air dryer at 80°C for 30 minutes, thereby obtaining a laminate containing the support and the coated film.

[0275] <Examples 29-42 and Comparative Examples 33-36>

[0276] Using the materials described in Table 4 below and the manufacturing conditions described in Table 4 below, except otherwise, a laminate comprising a support and a coated film was obtained. In the case of two coatings, the dried coating on the support obtained by the first coating and drying was coated in the same way as the first coating, and the resulting wet coating was dried in a hot air dryer at 80°C for 30 minutes.

[0277] <Coating thickness>

[0278] The thickness of the coating is calculated using the following formula.

[0279] The thickness of the coating [μm] = the concentration of the coating solution [mass%] × the thickness of the coating solution [μm] / 100

[0280] The concentration of the coating solution [mass %] = {(mass of coating solution [g] - mass of water contained in the coating solution [g]) / mass of coating solution [g]} × 100

[0281] The total thickness of the coating film in the case of two coatings is calculated by replacing "thickness of coating liquid" in the above formula with "total thickness of coating liquid".

[0282] <Bending resistance>

[0283] The laminate is bent with the coated side facing inwards. A 2kg rubber roller is moved back and forth across the bent area (crease) from one end to the other once to create a crease. Toluene colored with edible red is applied to a 10cm section of the crease on the coated side, and the presence of any bleed-through (small red spots or coloring of the entire coated side) is checked. If no bleed-through is observed, the same procedure is repeated to check for any bleed-through. The maximum number of bends without bleed-through is defined as the bending resistance [times], with a maximum value of 5 times. The higher this value, the better the mechanical strength of the coating layer and the less prone it is to cracking during bending.

[0284] <Oxygen permeability (OTR)>

[0285] The oxygen permeation rate (cc / m³) of the laminate was measured using an oxygen permeation rate measuring device (Systech illinois OXYSENSE MODEL8101e) under the following conditions. 2 ·day·atm).

[0286] Temperature: 23℃

[0287] Humidity on the oxygen supply side: 50%RH

[0288] Carrier gas side humidity: 50%RH

[0289] Carrier gas flow rate: 10 mL / min

[0290] Oxygen pressure: 1.0 atm

[0291] Carrier gas pressure: 1.0 atm

[0292] The evaluation results are shown in Table 4.

[0293]

Claims

1. A bag comprising a water-soluble film containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and derivatives thereof.

2. The bag according to claim 1, wherein, The polysaccharide A is selected from tamarind gum and its derivatives.

3. The bag according to claim 1, wherein, The content of polysaccharide A is 5-80% by mass relative to the mass of the water-soluble membrane.

4. The bag according to claim 1, wherein, The water-soluble film also contains plasticizers.

5. The bag according to claim 4, wherein, The plasticizer is at least one selected from the group consisting of polyols, hydroxy acids, monosaccharides, and disaccharides.

6. The bag according to claim 5, wherein, The plasticizer is selected from at least one of the following groups: glycerol, diglycerol, sorbitol, alkylene glycol, polyalkylene glycol, trimethylolpropane, erythritol, 2-methyl-1,3-propanediol, lactic acid, glucose, fructose, maltose, and trehalose.

7. The bag according to claim 6, wherein, The plasticizer is at least one selected from the group consisting of glycerol, ethylene glycol, sorbitol and fructose.

8. The bag according to claim 4, wherein, The content of the plasticizer is 20-95% by mass relative to the mass of the water-soluble film.

9. The bag according to claim 1, wherein, The water-soluble membrane also contains a polysaccharide B, which is different from polysaccharide A.

10. The bag according to claim 9, wherein, The polysaccharide B is selected from at least one of the following groups: guar gum, locust bean gum, xanthan gum, carrageenan, alginate, pullulan, and their derivatives.

11. The bag according to claim 9, wherein, The content of polysaccharide B is 1 to 30% by mass relative to the mass of the water-soluble membrane.

12. The bag according to claim 1, wherein, The toughness value of the water-soluble membrane is above 400.

13. The bag according to claim 1, which dissolves in water at 10°C within 1000 seconds.

14. The bag according to claim 1, wherein the interior contains at least one selected from the group consisting of a detergent, a fabric softener, and a fragrance.

15. A water-soluble membrane containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and derivatives thereof.

16. A water-soluble membrane comprising at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and derivatives thereof, and a polysaccharide B different from said polysaccharide A.

17. A water-soluble film for use in bags, comprising at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and derivatives thereof, and a plasticizer, wherein the content of the plasticizer is 45% by mass or less relative to the mass of the water-soluble film.

18. The water-soluble film according to any one of claims 15 to 17, wherein it is a coated film formed by a coating agent containing at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum and derivatives thereof.

19. A laminate comprising the water-soluble membrane and support as described in any one of claims 15-17, wherein, The support is paper or film.

20. A packaging material comprising the water-soluble film of claim 15.

21. A coating agent comprising at least one polysaccharide A selected from the group consisting of tamarind gum, locust bean gum, tara gum, and derivatives thereof.

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