Two-layer seamless capsule with water-soluble composition as inner content

Abstract

The present application provides a two-layer seamless soft capsule containing a water-soluble composition as an inner content. The capsule coating is prepared from an ultraviolet curable composition to produce a two-layer seamless capsule consisting of a capsule coating and an inner content which is a water-soluble composition, and the volatility of the inner content due to penetration of the coating is low.

Description

Technical Field

[0001] The present invention relates to a two-layer seamless capsule, which is composed of a capsule coating prepared from an ultraviolet curable resin composition and an inner content as a water-soluble composition. The capsule of the present invention can contain a water-soluble fragrance or the like as the inner content. Background Art

[0002] The dropping method (also known as the liquid hardening method) used in the manufacture of seamless capsules is a capsule manufacturing method that utilizes the surface tension between liquid and liquid (inner liquid-filming liquid, filming liquid-cooling oil) or the surface tension between gas and liquid (air-filming liquid). In the past, the following method was widely used: a water-soluble film-forming composition (such as an aqueous solution of gelatin, etc.) was sprayed from the outer nozzle of a concentric double-layer nozzle, and a hydrophobic inner liquid was sprayed from the inner nozzle to the cooled oil to form concentric double-layer droplets, and the outer droplets (filming liquid) were gelled by cooling to form capsules. There are the following problems in this manufacturing method: when the film-forming composition used as a film is water-soluble, the capsule contents are limited to oils or oil solutions of oil-soluble substances that have surface tension with the film-forming composition, and water-soluble components cannot be made into capsules. Therefore, methods have been developed in which a water-soluble component is dispersed in an oily liquid (see, for example, Patent Document 1) or emulsified (see, for example, Patent Documents 2 and 3) to form a capsule.

[0003] In addition, as a capsule to be enclosed in the filter part of a cigarette, the following capsule has been proposed: a shell formed by at least one hydrophilic colloid selected from gellan gum, agar, alginate, carrageenan, pectin, gum arabic, gum ghatti, pullulan, mannosum or modified starch, or a mixture thereof, or a mixture with gelatin; and a core composed of a lipophilic or partially ethanol-soluble substance or product, or an oil / water / oil emulsion (for example, refer to Patent Document 4).

[0004] On the other hand, as a capsule containing a hydrophilic substance as an inner content, a seamless capsule containing a hydrophilic substance as an inner content has been proposed: in a seamless capsule formed of an inner content and a coating covering the inner content, a low-order fatty acid ester of sucrose is sandwiched between the inner content and the coating (for example, see Patent Document 5). However, in such a capsule, the coating is not sufficiently separated from the components contained in the core, and the components contained in the core can only be temporarily prevented from directly contacting the capsule coating.

[0005] [Prior art literature]

[0006] [Patent Document]

[0007] [Patent Document 1] Japanese Patent Application Laid-Open No. 1-186815

[0008] [Patent Document 2] Japanese Patent Application Laid-Open No. 11-342329

[0009] [Patent Document 3] Japanese Patent Application Laid-Open No. 9-327501

[0010] [Patent Document 4] Japanese Patent Application Publication No. 2014-166188

[0011] [Patent Document 5] Japanese Patent Application Laid-Open No. 3-52639 Summary of the invention

[0012] Problems to be solved by the invention

[0013] The present invention aims to provide a two-layer seamless capsule containing a water-soluble composition as an inner content.

[0014] Solution to the problem

[0015] The inventors of the present invention studied various coating compositions when using water or a water-soluble composition such as a water-soluble flavoring agent as a capsule content, and found that by preparing the capsule coating with an ultraviolet curable resin composition, the volatility of the content due to permeation of the coating is reduced, thereby reducing the volatilization of the flavoring component, thereby completing the present invention. In addition, the present invention can be applied to seamless capsules with three or more layers.

[0016] That is, the present invention is as follows.

[0017] [1] A two-layer seamless capsule comprising a capsule coating made of an ultraviolet curable resin composition and an inner substance which is water or a water-soluble composition.

[0018] [2] The seamless capsule according to [1] above, wherein the viscosity of the ultraviolet curable resin composition is 20 to 2000 mPa·s.

[0019] [3] The seamless capsule according to [1] or [2] above, wherein the ultraviolet curable resin composition is an acrylic resin composition, an epoxy resin composition or a silicone resin composition.

[0020] [4] The seamless capsule according to any one of [1] to [3] above, wherein the acrylic resin composition contains an acrylic oligomer, an acrylic monomer, and a photopolymerization initiator.

[0021] [5] The seamless capsule according to any one of [1] to [4] above, wherein the water-soluble composition contains water, a water-soluble flavor, a water-soluble alcohol, glycerin or propylene glycol.

[0022] [6] The seamless capsule according to any one of [1] to [5] above, wherein the film thickness of the thinnest part of the capsule film measured by a three-dimensional X-ray microscope is 100 μm or more.

[0023] [7] The seamless capsule according to any one of [1] to [6] above, wherein the diameter is 1 to 6 mm.

[0024] [8] The seamless capsule according to any one of [1] to [7] above, wherein the mass reduction after storage at 20°C for 60 days is less than 5%.

[0025] [9] The seamless capsule according to any one of [1] to [8] above, wherein the seamless capsule is enclosed in a cigarette filter.

[0026]

[10] A method for producing a two-layer seamless capsule having an inner substance and a coating covering the inner substance, characterized by comprising:

[0027] (a) a step of preparing (preparing) water or a water-soluble composition as an inclusion substance;

[0028] (b) a step of preparing a UV-curable resin composition as a capsule coating liquid;

[0029] (c) Using a concentric double nozzle, the capsule coating liquid is sprayed from the outer nozzle and the water or water-soluble composition is sprayed from the inner nozzle toward the forming liquid to form two layers of droplets, and the two layers of droplets are irradiated with ultraviolet rays to solidify the capsule coating liquid to form a capsule coating.

[0030] According to the present invention, a seamless soft capsule in which the volatile components in the contents are less likely to volatilize can be provided. DETAILED DESCRIPTION

[0031] The two-layer seamless capsule of the present invention is not particularly limited as long as it is a two-layer seamless capsule consisting of a capsule film prepared (modulated) from a UV-curable resin composition and an inner substance which is a water-soluble composition. The capsule coating is obtained by irradiating the UV-curable resin composition with ultraviolet rays. The UV-curable resin is roughly divided into free radical polymerization type resin and cationic polymerization type resin according to different reaction mechanisms.

[0032] When the ultraviolet curable resin is a free radical polymerizable resin, the free radical polymerizable resin may preferably be an acrylic resin or a silicone resin. The acrylic resin is not particularly limited as long as the element constituting the polymer skeleton is a (meth)acrylic acid monomer. For example, the acrylic resin may be selected from (meth)acrylic acid, methyl (meth)acrylate, ethyl (meth)acrylate, n-propyl (meth)acrylate, isopropyl (meth)acrylate, n-butyl (meth)acrylate, isobutyl (meth)acrylate, tert-butyl (meth)acrylate, cyclohexyl (meth)acrylate, (meth)acrylate, The (meth)acrylic acid polymer may be one or more of (meth)acrylic acid polymers selected from (fluoro)alkyl (meth)acrylates such as 2-ethylhexyl (meth)acrylate, lauryl (meth)acrylate, octadecyl acrylate, benzyl (meth)acrylate, 2-trifluoroethyl (meth)acrylate, 2-hydroxyethyl (meth)acrylate, 2-hydroxypropyl (meth)acrylate, 4-hydroxybutyl (meth)acrylate, glycidyl (meth)acrylate, methylglycidyl (meth)acrylate, 3,4-epoxycyclohexylmethyl (meth)acrylate, (meth)acryloylmorpholine, allyl (meth)acrylate, etc. Unless otherwise specified, "(meth)acrylate" (or "(meth)acrylic acid") refers to methacrylate (or methacrylic acid) and / or acrylate (or acrylic acid).

[0033] Preferred examples of the acrylic resin composition include an acrylic resin composition containing a photopolymerizable (meth)acrylate oligomer and / or a photopolymerizable (meth)acrylate monomer and a photopolymerization initiator.

[0034] The photopolymerizable (meth)acrylate oligomer is not particularly limited as long as it is a (meth)acrylate oligomer having an acryloyl group as a free radical polymerizable functional group in the molecule, and examples thereof include (meth)acrylate oligomers or urethane (meth)acrylate oligomers having one or more skeletons selected from the group consisting of polyalkylene, polybutadiene, hydrogenated polybutadiene, polyisoprene and hydrogenated polyisoprene.

[0035] The acrylic acid ester monomer is not particularly limited, and examples thereof include monofunctional monomers such as 2-ethylhexyl acrylate, 2-hydroxyethyl acrylate, and 2-hydroxyethyl acryloyl phosphate, bifunctional monomers such as 1,3-butylene glycol diacrylate, 1,6-hexanediol diacrylate, and diethylene glycol acrylate, and trifunctional or higher acrylic acid monomers such as trimethylolpropane triacrylate, pentaerythritol triacrylate, and dipentaerythritol hexaacrylate. These monomers may be used alone or in combination of two or more.

[0036] The photopolymerization initiator contained in the acrylic resin composition is not particularly limited as long as it is a compound that can be responsive to ultraviolet rays and initiate free radical polymerization. Examples thereof include benzoyl alkyl ethers such as benzophenone, benzoyl ethyl ether, benzoyl methyl ether, and benzoyl isopropyl ether; 2,4,5-triarylimidazole dimers such as 2-(o-chlorophenyl)-4,5-diphenylimidazole dimer, 2-(o-chlorophenyl)-4,5-bis-(m-methoxyphenyl)imidazole dimer, and 2-(p-methoxyphenyl)-4,5-diphenylimidazole dimer; sulfur compounds such as dibenzyl sulfide and tetramethylthiuram sulfide; and the like.

[0037] As the above-mentioned acrylic resin composition, commercially available products can also be used, and specific examples include TB3042B, TB3066, TB3013D, TB3067, TB3064E, TB3094B (all manufactured by ThreeBond Co., Ltd.), Hitaroid 7975, Hitaroid 7988, Hitaroid 7975D (all manufactured by Hitachi Chemical Co., Ltd.), UV-7605B, UV-7620EA (all manufactured by Mitsubishi Chemical Holdings Corporation), Aronix series (manufactured by Toagosei Co., Ltd.), etc.

[0038] Silicone resin is a polymer compound with a siloxane bond as the main chain. As the silicone resin composition, commercial products can also be used, specifically, TB3161, TB3163, TB3164D (all manufactured by ThreeBond Co., Ltd.), KUV-3433-UV, KER-4700-UV, KER-4800-UV (all manufactured by Shin-Etsu Chemical Co., Ltd.), etc.

[0039] When the above-mentioned ultraviolet curing resin is a cationic polymerizable resin, an epoxy resin can be preferably cited as the cationic polymerizable resin; as the above-mentioned epoxy resin, one or more epoxy resins such as bisphenol A type epoxy resin, bisphenol F type epoxy resin, bisphenol S type epoxy resin, bisphenol AD ​​type epoxy resin, naphthalene type epoxy resin, biphenyl type epoxy resin, glycidylamine type epoxy resin, brominated bisphenol A type epoxy resin, hydrogenated bisphenol A type epoxy resin, alicyclic epoxy resin, dicyclopentadiene type epoxy resin, phenol novolac type epoxy resin, o-cresol novolac type epoxy resin and the like can be cited.

[0040] Preferred examples of the epoxy resin composition include an epoxy resin composition containing a cationically polymerizable compound that forms an epoxy resin and a photopolymerization initiator.

[0041] The cationically polymerizable compound forming the epoxy resin may include compounds having one or more epoxy groups having a cationically polymerizable group in one molecule; specifically, cyclopentadiene dioxide, (3,4-epoxycyclohexyl)methyl-3,4-epoxycyclohexanecarboxylate, bis(2,3-epoxycyclopentyl)ether, bis(3,4-epoxycyclohexylmethyl)adipate, bis(3,4-epoxy-6-methylcyclohexylmethyl)adipate, (3,4-epoxy- Epoxy compounds containing alicyclic epoxy groups such as 6-methylcyclohexyl)methyl-3,4-epoxy-6-methylcyclohexanecarboxylate, bis(3,4-epoxycyclohexylmethyl)acetal, bis(3,4-epoxycyclohexyl)ether of ethylene glycol, 3,4-epoxycyclohexanecarboxylic acid diester of ethylene glycol, (3,4-epoxycyclohexyl)methanol, (3,4-epoxycyclohexyl)ethyltrimethoxysilane, 3-ethyl-3-(3,4-epoxycyclohexylmethyl)oxymethyloxetane; ethylene glycol diglycidyl Oil ether, propylene glycol diglycidyl ether, polyethylene glycol diglycidyl ether, polypropylene glycol diglycidyl ether, 1,4-butanediol diglycidyl ether, neopentyl glycol diglycidyl ether, 1,6-hexanediol diglycidyl ether, glycerol diglycidyl ether, diglycerol tetraglycidyl ether, trimethylolpropane triglycidyl ether, spirodiol diglycidyl ether, 2,6-diglycidyl phenyl ether, sorbitol polyglycidyl ether, isocyanuric acid triglycidyl ester, bisphenol A diglycidyl ether, butadiene dioxide Epoxy compounds containing aliphatic epoxy groups, such as phthalic acid diglycidyl ester, 3-ethyl-3-glycidyloxymethyloxetane, halogenated bisphenol A type epoxy resin, bisphenol F type epoxy resin, o-, m-, p-cresol novolac type epoxy resin, phenol novolac type epoxy resin, etc.; epoxy compounds containing alicyclic epoxy groups and aliphatic epoxy groups, such as vinyl cyclohexene dioxide and limonene dioxide; etc.; these compounds can be used alone or in combination of two or more.

[0042] Examples of the photopolymerization initiator contained in the epoxy resin composition include compounds that react to ultraviolet rays to generate cationic polymerization initiators, such as ArN2·PFe - 、ArN2·SbFe - 、ArN2·AsFe - 、(ArN2 + )2SnCl6 - 、ArN2·FeCl4 - benzylmethylsulfonium salts such as p-phenylbenzylmethylsulfonium salt, p-phenyldimethylsulfonium salt, p-hydroxyphenylbenzylmethylsulfonium salt, or arylsulfonium salts such as triarylsulfonium salts such as triphenylsulfonium salt and diphenyl-4-thienyloxyphenylsulfonium salt.

[0043] As the epoxy resin composition, commercial products may be used, and specific examples thereof include TB3121D (manufactured by ThreeBond Co., Ltd.), Hitaroid 7663 (manufactured by Hitachi Chemical Co., Ltd.), Aron Oxetane (manufactured by Toagosei Co., Ltd.), and Luxidia series (manufactured by DIC Corporation).

[0044] A photosensitizer, a polymer gelling agent, a gelling aid, a film reinforcing agent, a plasticizer, a coloring agent, etc. may be added to the above-mentioned ultraviolet curable resin composition.

[0045] The viscosity of the ultraviolet curable resin composition is 20 to 2000 mPa·s, preferably 100 to 1500 mPa·s. If the viscosity is high, bubbles are easily entrained, making it difficult to handle during production and making it difficult to obtain good capsules.

[0046] As the inner contents of the two-layer seamless capsule of the present invention, any water-soluble composition (aqueous composition) is not particularly limited, and various hydrophilic substances can be dissolved in water. As the hydrophilic substance in the present invention, any water-soluble substance can be used as long as it has a functional group such as hydroxyl, carboxyl, amino, keto, sulfonic group, etc. that can easily form a bond with water molecules as part of its molecular structure, and is not particularly limited; specifically, water, water-soluble alcohols, glycerin, propylene glycol and other water-soluble solvents, water-soluble vitamins, sugar alcohols, natural sweeteners, artificial sweeteners, oligosaccharides, polysaccharides, water-soluble flavors, etc. can be cited.

[0047] Examples of the water-soluble vitamins include B vitamins such as vitamin B1 (thiamine), vitamin B2 (riboflavin), vitamin B3 (niacin, niacinamide), vitamin B5 (pantothenic acid, dexpanthenol), vitamin B6 (pyridoxine, pyridoxal phosphate, pyridoxamine), vitamin B7 (biotin), vitamin B9 (folic acid), vitamin B12 (cyanocobalamin, methylcobalamin), and vitamin C (ascorbic acid, dehydroascorbic acid).

[0048] Examples of the sugar alcohol include erythritol, xylitol, sorbitol, palatinitol, maltitol, lactitol, and mannitol.

[0049] Examples of the natural sweeteners include sucrose, stevia, glycyrrhizin, and monk fruit, and examples of artificial sweeteners include saccharin, aspartame, acesulfame potassium, and sucralose.

[0050] Examples of the oligosaccharides include fructooligosaccharides, galacto-oligosaccharides, xylo-oligosaccharides, palatinose oligosaccharides, agarose oligosaccharides, chitosan oligosaccharides, isomaltooligosaccharides, maltooligosaccharides, raffinose, lactulose, etc. In addition, examples of the polysaccharides include water-soluble polysaccharides that do not gel when cooled, such as propylene glycol alginate, gum arabic, gum tragacanth, gum karaya, gum ghatti, xanthan gum, guar gum, locust bean gum, tara gum, λ-carrageenan, μ-carrageenan, ν-carrageenan, cellulose, and starch.

[0051] The water-soluble flavoring agent is not particularly limited as long as it is a flavoring composition having the properties of a hydrophilic substance and has the functions of enhancing the original flavor of food (flavor enhancement), supplementing the original flavor of food raw materials (flavor imparting), correcting the flavor when an unsuitable odor for food is generated due to heating flavor or fermentation odor in the processing step (masking), etc., and the like, and examples thereof include water-soluble natural flavoring agents, water-soluble synthetic flavoring agents, water-soluble flavoring agents, and water-in-oil emulsified flavoring agents.

[0052] Specifically, there can be mentioned: the so-called recovered flavoring agent which is obtained by extracting the plant material with a water-soluble solvent such as water, ethanol, 1,3-butanediol, propylene glycol, glycerin, etc. after drying, chopping, pulverizing, etc.; the flavoring agent which is prepared by adding the plant to ethanol and stirring it, and then placing it at a low temperature to separate it into a lower layer (hydrous ethanol layer) containing the flavoring substance and an upper layer containing the water-insoluble component, and recovering the lower hydrous ethanol layer by filtering, etc.; the water-soluble flavoring agent which is prepared by extracting the plant material with an organic solvent, adding ethanol, glycerin, propylene glycol, etc., and recovering the solvent to obtain an aroma concentrate (for example, Japanese Patent Gazette No. 6032991).

[0053] Examples of the water-soluble natural flavor include citrus natural flavors such as lime, grapefruit, and orange, mango natural flavors, apple natural flavors, grape essence, pineapple natural flavors, and strawberry natural flavors.

[0054] The water-soluble synthetic fragrance is not particularly limited as long as it is a chemically synthesized water-soluble synthetic fragrance, and examples thereof include hexanol, phenethyl alcohol, cis-3-hexenol, nerolidol, isopentanol, citronellol, menthol, amyl alcohol, cinnamyl alcohol, 1-octen-3-ol, perillyl alcohol, farnesol, linalool, terpineol, geraniol, benzyl alcohol, furfuryl alcohol, and the like.

[0055] Examples of the water-soluble flavors (essences) include flavors and fragrances obtained by diluting a flavor base obtained by blending a variety of oil-soluble and / or water-soluble natural flavors and synthetic flavors with a water-soluble substance such as ethanol or glycerin, and examples thereof include lemon flavor, lime flavor, grapefruit flavor, orange flavor, grapefruit flavor, apple flavor, melon flavor, mint flavor, honey flavor, strawberry flavor, black currant flavor, cranberry flavor, cherry flavor, pineapple flavor, papaya flavor, banana flavor, blueberry flavor, mango flavor, peach flavor, pear flavor, green tea flavor, black tea flavor, cocoa flavor, chocolate flavor, coffee flavor, yogurt flavor, cinnamon flavor, ginger flavor, thyme flavor, nutmeg flavor, mint essence, and vanilla essence.

[0056] As the above-mentioned oil-in-water emulsified flavor, there can be mentioned an oil-in-water emulsion (emulsified flavor) obtained by emulsifying and dispersing a flavor containing an oil-soluble natural flavor / synthetic flavor in an aqueous solution using a gum arabic solution, carboxymethyl cellulose, saponin, lecithin, etc. as an emulsifier; examples include pineapple emulsified flavor, orange emulsified flavor, coffee emulsified flavor, butter emulsified flavor, cheese emulsified flavor, etc.

[0057] Examples of the powdered flavors include water-soluble flavors in powder form obtained by emulsifying a flavor base prepared by blending a variety of natural flavors or synthetic flavors with excipients such as dextrin, natural gum, sugar, and starch, and then spray-drying the mixture. Examples include lemon powdered flavor, orange powdered flavor, apple powdered flavor, butter powdered flavor, cheese powdered flavor, and vanilla powdered flavor.

[0058] The above-mentioned inclusions may be prepared by further adding water-soluble pigments, thickening polysaccharides, dietary fibers such as pectin, etc., within a range not impairing the effects of the present invention.

[0059] As a method for producing the two-layer seamless capsule of the present invention, a conventional method for producing seamless capsules can be cited, such as a dropping method; a UV-curable resin composition as a coating liquid is ejected from the outer nozzle of a concentric double nozzle, and a water-soluble composition as an inner component is ejected from the inner nozzle, respectively, and introduced into the forming liquid, and two layers of droplets are formed by surface tension. The UV-curable resin composition as a coating liquid on the outer side of the two layers of droplets is irradiated with ultraviolet rays and cured while moving in the forming liquid, forming a capsule coating, and a capsule containing a water-soluble composition is formed.

[0060] In the above-mentioned two layers of droplets, the method for curing the resin in the ultraviolet curable resin composition is not particularly limited as long as it is a method that can cure the coating by irradiating ultraviolet rays. An example of this is a method in which the capsule and the forming liquid are introduced into a tube made of a material with high ultraviolet transmittance such as glass or quartz, and the tube is clamped to irradiate with a UV light source from one or more directions.

[0061] The wavelength of ultraviolet light when curing the resin composition by ultraviolet light of the present invention is preferably in the energy range of 210 nm to 470 nm, more preferably in the energy range of 270 to 410 nm. As the light intensity, the accumulated light quantity is 5 kJ / m 2 ~50kJ / m 2 , preferably 10 kJ / m 2 ~35kJ / m 2 In order to obtain such a light intensity, in order to obtain a predetermined cumulative light intensity, it is necessary to appropriately change the capsule movement speed and irradiation speed. For example, when the cumulative light intensity required is 15 kJ / m 2 When the capsule movement speed is set to 5cm / s, the irradiation speed is set to 3W / cm 2 (working distance 5mm), irradiate for more than 2 seconds.

[0062] As the forming liquid in the method for producing the two-layer structure seamless capsule of the present invention, water or a viscous water-soluble composition can be preferably mentioned, and specifically, gum arabic, arabic galactan, karaya gum, ghatti gum, tragacanth gum, locust bean gum, guar gum, psyllium gum, tamarind gum, tara gum, alginic acid, carrageenan, agar, low molecular weight agar, furcellaran, pectin, curdlan gum, xanthan gum, gellan gum, pullulan gum, cellulose, chitosan and other so-called thickening polysaccharide aqueous solutions, soluble starch, starch paste, sorbitol liquid and other liquid sugar alcohols, glycerol and other polyols, reduced maltose syrup and other syrups, etc., can be mentioned. Any substance that makes water viscous by dissolving in water or mixing with water is not particularly limited, and the viscosity suitable for use can be adjusted by appropriately changing the dilution rate in water.

[0063] In conventional capsule manufacturing, a time-consuming drying process is generally required. In the capsule manufacturing process after ultraviolet irradiation of the present invention, a drying process such as rotary drying with ventilation or vacuum drying is not necessarily required, which can improve the efficiency of the manufacturing process, which is also an extremely advantageous aspect.

[0064] The capsule of the present invention can release the contents for use by rupturing or adding cracks to the capsule membrane in some way. As a method of rupturing the capsule membrane, for example, a part of the human body or some tool can be used to squeeze it. As a method of adding cracks to the capsule membrane, for example, a sharp tool such as a knife can be used to make an incision.

[0065] The volatility (rate) of the capsule of the present invention, when expressed as a mass reduction rate after the capsule is stored at 20° C. for 60 days, is less than 5%, preferably less than 3%.

[0066] The film thickness of the thinnest part of the capsule film of the capsule of the present invention is preferably 100 μm or more. The film thickness of the thinnest part of the capsule film can be measured using a three-dimensional X-ray microscope.

[0067] The shape of the seamless capsule of the present invention is not particularly limited, but is usually spherical. It can also be formed into shapes other than spherical, such as rugby ball shape (Oval) or elliptical shape (Oblong) by applying some external force during molding.

[0068] The particle size of the seamless capsule of the present invention is 1 to 6 mm, preferably 2 to 5 mm.

[0069] The mass of the seamless capsule of the present invention is 10 to 300 mg, preferably 20 to 200 mg, and more preferably 50 to 150 mg.

[0070] Examples of uses of the seamless capsule of the present invention include flavor capsules enclosed in cigarette filters, aromatics, cosmetics, and daily necessities.

[0071] Hereinafter, the present invention will be described in more detail by way of examples, but the technical scope of the present invention is not limited to these examples.

[0072] [Example]

[0073] [Example 1]

[0074] Table 1 shows the ultraviolet curable resins used in the following examples.

[0075] [Table 1]

[0076]

[0077] ※Viscosity: B-type viscometer (TOKIMEC)

[0078] (capsule containing water)

[0079] As the UV-curable resin composition, an acrylate resin composition obtained from the UV-curable resin A listed in Table 1 containing an acrylate oligomer, an acrylate monomer, acrylic acid and a photopolymerization initiator is used to prepare a capsule coating, and a two-layer seamless capsule is made with water as the inner content.

[0080] Using a concentric double-layer nozzle (manufactured by Fuji Capsule Co., Ltd.), the acrylic resin composition was ejected from the outer nozzle and water was ejected from the inner nozzle to form two layers of droplets. The moving speed of the two layers of droplets in the forming liquid adjusted to a viscosity of 10 mPa·s (25° C.; B-type viscometer) was set to 5 cm / s.

[0081] The two layers of droplets were introduced into a 20 cm glass tube together with the forming liquid, and two linear UV light sources (E110II-HD, Ushio Electric Co., Ltd.) were set up in two directions to connect to the glass tube, and ultraviolet rays (wavelength 365 nm) were irradiated to cure the coating. Since the cumulative light amount used to cure the ultraviolet curable resin composition is 15 kJ / m 2 Therefore, the flow rate of the forming liquid was adjusted so that the capsule movement speed was about 5 cm / s, and the irradiation intensity was 3 W / cm 2 (Working distance 5mm) irradiate for more than 2 seconds.

[0082] (Volatilization test)

[0083] For the above-mentioned water-enclosed capsules, the film thickness of the thinnest part of the capsule coating was measured using a "high-resolution three-dimensional X-ray microscope Nano3DX" (manufactured by Rigaku Corporation). Five capsules with a measured film thickness of the thinnest part of the capsule coating of more than 100 μm were selected, and the average total mass was measured. The capsules were stored in glass bottles at 20°C, and the reduction rate compared with the mass on the storage start day was calculated based on the total mass measured on the 30th and 60th days. The results are shown in Table 2.

[0084] [Table 2]

[0085]

[0086] (result)

[0087] As shown in Table 2, when water was used as the inner substance, the mass change of the capsules with a thinnest film thickness of 100 μm or more after 60 days was less than 5%, indicating low volatility, and it is considered that the inner substance was enclosed.

[0088] (Severe volatility test)

[0089] The volatility of the capsules prepared by using water and the grapefruit flavor aqueous solution as the inner contents and UV curable resin A as the UV curable resin composition was rigorously tested. After measuring the mass of the capsules, the capsules were stored under vacuum conditions (50 hPa) for 30 minutes, and then the mass was measured and the reduction rate was calculated. The results are shown in Table 3.

[0090] [Table 3]

[0091] Strict test (evaluation of internal liquid permeability)

[0092]

[0093] *: In Comparative Example 1, the "reduction" is 2%, but the volatile components contained in the capsule content are only 10% (diluted with MCT), and the volatilization amount of the volatile components is about 20%.

[0094] As can be seen from Table 3, the mass reduction rate of the conventional carrageenan-coated capsule (comparative example) is about 20% of the amount of volatile components, which is considered to be due to the leakage of volatile components in the fragrance through and through the film. On the other hand, in the capsule containing water and the capsule containing grapefruit essence having a coating prepared from an ultraviolet curable resin composition, there is no mass change (0%) under vacuum conditions, thus confirming that the capsule coating of the present invention can seal the volatile components contained in the contents.

[0095] [Example 2]

[0096] (Water-filled capsules using other resins - 1)

[0097] As the ultraviolet curable resin composition, a silicone resin composition obtained from the ultraviolet curable resin B listed in Table 1 was used to prepare a capsule coating, and water was used as the inner content. The two-layer seamless capsule was manufactured in the same manner as in Example 1, and each capsule was able to be manufactured normally.

[0098] The above two layers of droplets are introduced into a 20 cm colorless transparent tube together with a solidifying liquid forming liquid. Two linear UV light sources (E110II-HD, manufactured by Ushio Electric Co., Ltd.) are set from two directions in a manner of clamping the tube, and ultraviolet rays (wavelength 365 nm) are irradiated to solidify the coating, resulting in the formation of capsules.

[0099] [Comparative Example 2]

[0100] (Water-filled capsules using other resins - 2)

[0101] As the ultraviolet curable resin composition, an acrylic resin composition obtained from the ultraviolet curable resin C listed in Table 1 was used to prepare a capsule film, and water was used as the inner substance. An attempt was made to prepare a two-layer seamless capsule according to Example 1, but no good capsule could be formed.

[0102] [Industrial Applicability]

[0103] The seamless capsule of the present invention can be used in the fields of pharmaceuticals, cosmeceuticals, cosmetics, household products, industrial products, etc. as a seamless capsule containing a water-soluble composition capable of stably retaining a hydrophilic volatile substance for a long period of time.

Claims

1. A two-layer seamless capsule, characterized in that: It is composed of a capsule coating prepared from an ultraviolet curable resin composition and an inner inclusion of water or a water-soluble composition; The ultraviolet curable resin composition is an acrylic resin composition containing acrylic oligomers, acrylic monomers, acrylic acid and a photopolymerization initiator; The viscosity of the acrylic resin composition is 20 to 2000 mPa·s; The mass loss after storage at 20°C for 60 days was less than 5%.

2. The seamless capsule according to claim 1, characterized in that Water-soluble compositions contain water or water-soluble fragrances.

3. The seamless capsule according to claim 1, characterized in that: The water-soluble composition contains water-soluble alcohols.

4. The seamless capsule according to claim 1, wherein Water-soluble compositions contain glycerin or propylene glycol.

5. The seamless capsule according to any one of claims 1 to 4, characterized in that The film thickness of the thinnest portion of the capsule film measured using a three-dimensional X-ray microscope was 100 μm or more.

6. The seamless capsule according to any one of claims 1 to 4, characterized in that The diameter is 1 to 6 mm.

7. The seamless capsule according to any one of claims 1 to 4, characterized in that Enclosed in the filter of cigarettes.

8. A method for manufacturing a seamless capsule according to any one of claims 1 to 7, characterized in that: have: (a) a step of preparing water or a water-soluble composition as an inclusion body; (b) a step of preparing a UV-curable resin composition as a capsule coating liquid; (c) using a concentric double nozzle, spraying the capsule coating liquid from the outer nozzle and the water or water-soluble composition from the inner nozzle toward the forming liquid to form two layers of droplets, and irradiating the two layers of droplets with ultraviolet rays to solidify the capsule coating liquid to form a capsule coating.

Images