Fragrance-retaining coating composition and laminate

Abstract

To provide a fragrance-retaining coating composition and laminate that provide excellent fragrance retention regardless of the type of fragrance. [Solution] A fragrance-retaining coating composition containing a hydroxyl group-containing polyester resin with a glass transition temperature in the range of 40 to 120°C, and a solvent.

Description

[Technical Field]

[0001] The present invention relates to a fragrance-retaining coating composition and laminate used for packaging beverages, foods, detergents, cosmetics, etc., that contain fragrance components such as alcoholic beverages, flavored beverages, coffee powder, fragrance powder, fabric softeners, liquid detergents, shampoos, conditioners, and perfumes. [Background technology]

[0002] For packaging beverages, foods, detergents, and cosmetics containing aromatic components such as alcoholic beverages, flavored beverages, coffee powder, fragrance powder, fabric softeners, liquid detergents, shampoos, conditioners, and perfumes, films with high fragrance retention properties (such as films laminated with highly barrier-type polyvinyl alcohol resin or ethylene-vinyl alcohol copolymer resin) have been used to prevent the fragrance from escaping the container. While the tendency of such films to prevent the permeation of fragrance components and maintain their scent might initially seem related to their gas barrier properties, these tendencies do not necessarily coincide in reality. Furthermore, packaging materials that retain fragrance are known to consist of a resin film with a metal layer or metal oxide layer. However, the metal foil layer or metal oxide layer contained in both types of materials is not resin, making collection and recycling difficult. Furthermore, if items containing a large amount of aromatic compounds are stored in containers with insufficient fragrance retention, even if they are airtight, the aromatic compounds will leak out of the container over time. As a result, when aromatic compounds leak from products displayed in stores, because there are many products on display, even if only a small amount of aromatic compounds permeates from one product, the total amount of leakage is large, and consequently, the entire sales floor becomes filled with fragrance.

[0003] Patent documents 1 and 2 describe polyester polyols that have low oxygen permeability, but whose permeability to fragrance components is unknown. Patent Document 3 describes a laminate for liquid packaging that has low oxygen permeability and excellent aroma retention, achieved by combining a specific heat-seal layer, a coating layer, and an adhesive layer. [Prior art documents] [Patent Documents]

[0004] [Patent Document 1] Patent No. 7207617 [Patent Document 2] Patent No. 7529179 [Patent Document 3] International Publication No. 2024 / 135510 [Overview of the project] [Problems that the invention aims to solve]

[0005] In recent years, there has been a growing demand for the development of films with high fragrance retention capabilities, regardless of the type of fragrance. This invention has been made in view of the above circumstances, and aims to provide a fragrance-retaining coating composition and laminate that can obtain excellent fragrance retention regardless of the type of fragrance. [Means for solving the problem]

[0006] The inventors of the present invention have conducted extensive research to solve the above problems and have found that the above problems can be solved by the compositions shown below, thereby completing the present invention. 1. A fragrance-retaining coating composition containing a hydroxyl group-containing polyester resin with a glass transition temperature in the range of 40 to 120°C, and a solvent. 2. The fragrance-retaining coating composition according to claim 1, further comprising a polyisocyanate curing agent as a curing agent. 3. The fragrance-retaining coating composition according to 2, wherein the polyisocyanate curing agent is a trifunctional or more isocyanate curing agent. 4. A laminate having at least a base layer, a layer made of the fragrance-retaining coating composition described in any of 1 to 3, and a heat-seal layer. 5. The amount of the layer made of the fragrance-retaining coating composition after drying is 0.15 to 1.0 g / m². 2 The laminate described in 4, which is within the range. [Effects of the Invention]

[0007] The present invention is a fragrance-retaining coating composition containing a hydroxyl group-containing polyester resin and a solvent with a glass transition temperature in the range of 40 to 120°C. Therefore, when applied to a film, it exhibits excellent fragrance retention regardless of the type of fragrance. [Modes for carrying out the invention]

[0008] The present invention relates to a fragrance-retaining coating composition containing a hydroxyl group-containing polyester resin with a glass transition temperature in the range of 40 to 120°C and an organic solvent. More preferably, the present invention relates to a fragrance-retaining coating composition further containing a polyisocyanate curing agent. The fragrance-retaining coating composition does not necessarily have to contain at least one of the following as a component that reacts with the curing agent: a compound having an active hydrogen group with a molecular weight of 100 to 250, and a compound having an active hydrogen group with a solubility parameter of 29.5 or less. Furthermore, it does not necessarily have to contain a polyester compound having an amino group at its terminus, but it may or may not. Furthermore, the fragrance-retaining coating composition may or may not contain plate-like inorganic compounds or compounds having a phosphate structure.

[0009] <Fragrance-retaining coating composition> (Hydroxyl group-containing polyester resin with a glass transition temperature in the range of 40-120°C) In the present invention, one or more hydroxyl group-containing polyester resins with glass transition temperatures in the range of 40 to 120°C can be used. In the present invention, a hydroxyl group-containing polyester resin that is a condensate of a low molecular weight diol and a dibasic acid is preferred as the hydroxyl group-containing polyester resin. The low molecular weight diol is preferably at least one of an aliphatic diol, an alicyclic diol, and an aromatic diol.

[0010] For example, one or more selected from low molecular weight diols with or without a branched structure such as ethylene glycol, diethylene glycol, dipropylene glycol, tripropylene glycol, 1,4-butanediol, 1,5-pentanediol, 1,6-hexanediol, neopentyl glycol, 1,2-propanediol, 1,3-butanediol, 2-methyl-1,3-propanediol, 1,4-pentanediol, 3-methyl-1,5-pentanediol, 2,5-hexanediol, 2-methyl-1,4-pentanediol, 2,4-diethyl-1,5-pentanediol, 2-butyl-2-ethyl-1,3-propanediol, 2-methyl-1,8-octanediol, 2,2,4-trimethyl-1,3-pentanediol, 2,2,4-trimethyl-1,6-hexanediol, cyclohexanedimethanol, tricyclodecanedimethanol, etc. are preferred. However, the low molecular weight diol may consist only of ethylene glycol, or other low molecular weight diols may be used in combination.

[0011] Examples of aromatic diols include hydroquinone, resorcinol, catechol, naphthalenediol, biphenol, bisphenol A, bisphenol F, tetramethylbiphenol, and ethylene oxide extensions and hydrogenated alicyclics thereof. Also, if necessary, glycerin, trimethylolpropane, trimethylolethane, tris(2-hydroxyethyl)isocyanurate, 1,2,4-butanetriol, pentaerythritol, dipentaerythritol, etc. may be blended as polyhydric alcohols with a trivalent or higher valence with the above low molecular weight diols, but it is not necessary to blend them.

[0012] Examples of the dibasic acid include aliphatic dibasic acids and polyvalent carboxylic acids such as aromatic dibasic acids, such as adipic acid, phthalic acid, isophthalic acid, terephthalic acid, 2,3-naphthalenedicarboxylic acid, 2,6-naphthalenedicarboxylic acid, 1,4-naphthalenedicarboxylic acid, 1,8-naphthalenedicarboxylic acid, maleic acid, fumaric acid, succinic acid, sebacic acid, oxalic acid, malonic acid, glutaric acid, pimelic acid, suberic acid, azelaic acid, or anhydrides thereof. Further, if necessary, trimellitic acid, pyromellitic acid or the like may be blended with the dibasic acid as a polybasic acid having three or more functional groups, but it is not necessary to blend them. Note that the hydroxyl group-containing polyester resin having a glass transition temperature in the range of 40 to 120°C does not have to be a polyester polyol having an isocyanuric ring. In order to obtain a polyester polyol by reacting the above diol compound and dibasic acid in the present invention, these are reacted in the presence of a catalyst. As such a catalyst, a general one among the catalysts used for the reaction of the diol compound and dibasic acid can be employed.

[0013] The glass transition temperature of the hydroxyl group-containing polyester resin is the measured glass transition temperature determined by thermal analysis. As a method of thermal analysis, in accordance with JIS K7121 (Method for Measuring Transition Temperature of Plastics), for example, using Pyris1 DSC manufactured by PerkinElmer, the glass transition temperature can be measured under the conditions of a heating rate of 20°C / min and a nitrogen gas flow rate of 20 milliliters / min. The glass transition temperature of the hydroxyl group-containing polyester resin is in the range of 40 to 120°C. Preferably it is 50°C or higher, more preferably 55°C or higher, still more preferably 58°C or higher, and most preferably 62°C or higher. Also preferably it is 110°C or lower, more preferably 100°C or lower, still more preferably 95°C or lower, and most preferably 90°C or lower. When the glass transition temperature of the polyester resin is lower than 40°C, the aroma retention tends to decrease, and when it is higher than 120°C, the coating film obtained from the resulting composition becomes hard, so the adhesion and aroma retention tend to decrease.

[0014] (Hydroxyl value) The range of the hydroxyl value of the hydroxyl group-containing polyester resin is preferably in the range of 1 to 200 mgKOH / g, and more preferably in the range of 1 to 100 mgKOH / g. The hydroxyl value can be determined by applying the method specified in JIS K1557-1:2007. Specifically, the hydroxyl groups of the polyester resin sample are acetylated by dissolving it in a pyridine solution containing an acetylating reagent (e.g., acetic anhydride). Then, the excess acetylating reagent is hydrolyzed with water, and the amount of acetic acid produced is titrated with potassium hydroxide. At this time, the carboxyl groups contained in the polyester resin are also titrated by potassium hydroxide, so the hydroxyl value (mgKOH / g) is calculated by subtracting the acid value of the polyester resin from the titration result.

[0015] Examples of such polyesters include Elitel UE9800 (Unitika Corporation) (a copolymer polyester containing ethylene glycol and propylene glycol as diol copolymer components, and terephthalic acid as a dicarboxylic acid copolymer component), Elitel UE-9200 (Unitika Corporation), DYNAPOL L 912 (EVONIK Corporation), and Pluscoat RZ-105 (Go-o Chemical Co., Ltd.).

[0016] (Hardening agent) A curing agent containing a polyisocyanate compound can be used, or it may not be necessary. Examples of polyisocyanate compounds include aromatic aliphatic diisocyanates, aliphatic diisocyanates, and alicyclic diisocyanates. Among these, isocyanate curing agents with three or more functionalities are preferred. Specific examples of aromatic aliphatic diisocyanates include 1,3- and / or 1,4-phenylenediisocyanate, 4,4-diisocyanatobiphenyl, 3,3-dimethyl-4,4-diisocyanatobiphenyl, 1,3- or 1,4-xylylenediisocyanate, 1,3- or 1,4-bis(1-isocyanato-1-methylethyl)benzene or mixtures thereof, ω,ω'-diisocyanato-1,4-diethylbenzene, α,α,α',α'-tetramethylxylylenediisocyanate, and the like.

[0017] Specific examples of aliphatic diisocyanates include 1,6-hexamethylene diisocyanate, tetramethylene diisocyanate, 2-methylpentane-1,5-diisocyanate, 3-methylpentane-1,5-diisocyanate, lysine diisocyanate, and trioxyethylene diisocyanate. Specific examples of alicyclic diisocyanates include isophorone diisocyanate, cyclohexane diisocyanate, hydrogenated diphenylmethane diisocyanate, norbornane diisocyanate, hydrogenated tolylene diisocyanate, hydrogenated xylene diisocyanate, and hydrogenated tetramethylxylene diisocyanate. Furthermore, it is acceptable to use a mixture of two or more such isocyanate compounds.

[0018] Furthermore, it is preferable to use components such as adducts obtained by reacting the above-mentioned diisocyanate compound with low-molecular-weight active hydrogen compounds such as ethylene glycol, propylene glycol, metaxylylene alcohol, 1,3-bishydroxyethylbenzene, 1,4-bishydroxyethylbenzene, trimethylolpropane, glycerol, pentaerythritol, erythritol, sorbitol, ethylenediamine, monoethanolamine, diethanolamine, triethanolamine, metaxylylenediamine and their alkylene oxide adducts, various polyester resins, polyether polyols, and high-molecular-weight active hydrogen compounds such as polyamides, biuret compounds obtained by trimerizing the above-mentioned diisocyanate compound, and isocyanurate compounds obtained by isocyanurating the above-mentioned diisocyanate compound.

[0019] From an environmental perspective, a biomass-based curing agent containing biomass polyol compounds and biomass polyisocyanate compounds is preferred. However, a non-biomass-based curing agent may also be used. As a biomass curing agent, a trifunctional isocyanate compound having an isocyanurate ring obtained by nurating biomass diisocyanate may also be used. Biomass isocyanates can also be obtained by using plant-derived amino acids as raw materials and converting their amino groups to isocyanate groups. For example, lysine diisocyanate (LDI) is obtained by methyl esterifying the carboxyl group of lysine and then converting the amino group to an isocyanate group. Similarly, 1,5-pentamethylene diisocyanate is obtained by decarboxylating the carboxyl group of lysine and then converting the amino group to an isocyanate group. Polymers or oligomers obtained by polymerizing the above isocyanate compounds and diol compounds so that the terminal ends are isocyanate groups can also be used.

[0020] As a trifunctional isocyanate compound having an isocyanurate ring, a trifunctional isocyanate compound having an isocyanurate ring obtained by nurating an isocyanate having two isocyanate groups in the molecule can be used. The chemical equivalent ratio of the hydroxyl group of the polyol compound and the isocyanate group of the polyisocyanate compound in the curing agent is preferably 1:1 to 1:5.

[0021] (solvent) Organic solvents and / or water can be used as solvents. Examples of organic solvents include toluene, ketone-based organic solvents (e.g., acetone, methyl ethyl ketone, methyl isobutyl ketone, etc.), ester-based solvents (e.g., methyl acetate, ethyl acetate, n-propyl acetate, n-butyl acetate, isobutyl acetate, etc.), alcohol-based solvents (e.g., methanol, ethanol, n-propanol, isopropanol, butanol, etc.), and hydrocarbon-based solvents (e.g., toluene, methylcyclohexane, etc.).

[0022] (Other ingredients) Other components that the fragrance-retaining coating composition may contain, to the extent that they do not impair the effects of the present invention, include hydroxyl group-containing polyester resins other than hydroxyl group-containing polyester resins with a glass transition temperature of 40 to 120°C, and other polyol compounds. It may also contain pigments such as known extender pigments and coloring pigments, pigment dispersants, dyes, and the like. Furthermore, a catalyst can be used during the reaction between the polyester polyol and the isocyanate curing agent. Among these, organometallic compounds are preferred, and such organometallic compounds include titanium compounds such as dibutyltitanium dichloride, tetrabutyltitanate, and butoxytitanium trichloride, as well as dibutyltin sulfide, tributyltin sulfide, tributyltin oxide, dibutyltin dichloride, dibutyltin oxide, dibutyltin dibromide, dibutyltin dimaleate, dibutyltin dilaurate, dibutyltin diacetate, dioctyltin dilaurate, and tributyltin dichloromide. Examples include tin acetate, tributyltin chloride, triethyltin ethoxide, tributyltin ethoxide, dioctyltin oxide, tributyltin trichloroacetate, and tin 2-ethylhexanoate; lead compounds such as lead oleate, lead 2-ethylhexanoate, lead benzoate, and lead naphthenate; and iron 2-ethylhexanoate, iron acetylacetonate, cobalt benzoate, cobalt 2-ethylhexanoate, zinc naphthenate, zinc 2-ethylhexanoate, and zirconium naphthenate. Among these, titanium compounds such as tetrabutyl titanate are preferred. Tertiary amine compounds can also be used, for example, triethylamine, triethylenediamine, 1,4-diazabicyclo(2,2,2)octane, and 1,8-diazabicyclo(5,4,0)-undecene-7 (DBU).

[0023] <Aromatic Laminate Using an Aromatic Coating Composition and Method for Producing the Same> (Fragrance-retaining laminate) The aroma-retaining laminate of the present invention can be used in applications that take into account its excellent aroma-retaining properties. Such applications include sealed containers in which at least a portion is formed by the aroma-retaining laminate of the present invention, and which can be sealed after the contents are stored inside. The contents contain a sufficient amount of aroma components and can be in solid or liquid form. The fragrance-retaining laminate of the present invention is based on layers formed by sequentially laminating a base material, a layer made of a fragrance-retaining coating composition, and, if necessary, a sealant layer. A printing layer, a primer layer, or the like can also be provided between the layer made of the fragrance-retaining coating composition and the substrate layer, and / or between the layer made of the fragrance-retaining coating composition and the sealant layer. Furthermore, the fragrance-retaining laminate may or may not have a metal vapor-deposited layer, a vapor-deposited layer of other inorganic compounds, or thin layers thereof. The absence of these layers is preferable because it eliminates the need to remove them during the processing of the fragrance-retaining laminate after use.

[0024] (base material layer) The base material layer used in the aroma-retaining laminate of the present invention may be a known material, and it is sufficient if it can be used as a packaging material for foods, daily necessities, etc. containing aroma components, and is positioned as the innermost or outermost layer in the packaging container when these are packaged. Such a base layer is not particularly limited as long as it is a layer that does not have fragrance retention properties. The base layer can be selected from polyolefins such as polyethylene, polypropylene, and ethylene-propylene copolymer, polyesters such as polyethylene terephthalate, polyamides, unoriented films, uniaxially oriented films, biaxially oriented films, paper, and woven or nonwoven fabrics that can form a layer made of a fragrance retention coating composition.

[0025] (Fragrance-retaining coating composition layer) The fragrance-retaining coating composition of the present invention allows for the formation of a coating layer by known means. These known means include roll coating methods using gravure cylinders, doctor knife methods, air knife / nozzle coating methods, bar coating methods, spray coating methods, dip coating methods, and coating methods combining these methods. If necessary, the surface of the substrate layer may be pre-coated with an anchor coating agent (AC agent) such as a urethane-based or acrylic-based agent using a known method. Furthermore, in packaging containers obtained by printing ink using front-side printing, it is preferable to coat the fragrance-retaining coating composition layer on the outer surface when the container is assembled, similar to the printing ink, from the viewpoint of preventing the fragrance-retaining coating composition layer from directly contacting the contents. Also, in packaging containers obtained by printing ink using back-side printing, it is preferable to coat the fragrance-retaining coating composition layer on the inner surface when the container is assembled, similar to the printing ink, from the viewpoint of protecting the fragrance-retaining coating composition layer.

[0026] The amount of the fragrance-retaining coating composition layer applied after drying in the laminate of the present invention varies depending on the base layer and the desired level of fragrance retention, but is generally between 0.08 and 5.0 g / m². 2 It is preferable that this be the case. Furthermore, from the viewpoint of reducing residual solvent in the fragrance-retaining coating composition layer and obtaining fragrance retention, 1.5 g / m² 2 The following is preferable: Application amount of 0.08 g / m² 2 If the amount is less than 5.0 g / m², the desired aroma retention may not be achieved. 2 It is difficult to further improve fragrance retention beyond this point, and moreover, a large amount of residual solvent may remain in the fragrance-retaining coating composition layer. Preferably 0.08 g / m 2 The above is more preferable, 0.15 g / m 2 The above is true, and more preferably 0.2 g / m 2 That's all. The fragrance-retaining coating composition layer may also be a layer formed by impregnating paper, woven fabric, or nonwoven fabric with the fragrance-retaining coating composition. The laminate of the present invention has a coating amount of the fragrance-retaining coating composition of 0.15 to 1.0 g / m 2 Even when it is a very thin film, it is a laminate having sufficient fragrance-retaining property and excellent processing suitability.

[0027] (Heat-sealing layer) When the fragrance-retaining laminate of the present invention has a heat-sealing layer, the heat-sealing layer may be a dried coating film layer of a heat-sealing agent or a sealant layer. The heat-sealing layer that may be used can be formed by applying and drying a heat-sealing agent. The heat-sealing agent used for forming the heat-sealing agent is not particularly limited, and may be in any form such as a type in which a thermoplastic resin having heat-sealing property is dissolved in an organic solvent, a type dissolved in water or an aqueous organic solvent, or an emulsion type dispersed in water or an aqueous organic solvent. The sealant layer that may be used can be formed by extrusion lamination or dry lamination. As the extrusion lamination method, after applying the above-mentioned anchor coating agent as necessary on the surface of the layer composed of the fragrance-retaining coating composition provided on one surface of the base film, the above-mentioned polyethylene, polypropylene, ethylene-vinyl acetate copolymer, etc. for forming a sealant film in a molten state are extruded and laminated by a known extrusion laminator. The method can be used. Further, the molten resin can be laminated in a sandwich shape with other materials as an intermediate layer.

[0028] As the dry lamination method, after applying a known adhesive on the surface of the layer composed of the fragrance-retaining coating composition provided on one surface of the base film of the base film, a polyolefin such as uniaxially stretched polyethylene, uniaxially stretched polypropylene, biaxially stretched polyethylene, biaxially stretched polypropylene, unstretched polyethylene, unstretched polypropylene, or ethylene-vinyl acetate copolymer is laminated by a known dry laminator. The method of bonding the sealant film can be used.

[0029] (An anchor coating agent used as needed in the extrusion lamination process) When the laminate layer of the fragrance-retaining laminate of the present invention is formed by extrusion lamination, suitable anchor coating agents that can be used as needed include imine-based anchor coating agents, isocyanate-based anchor coating agents, and the like. Specifically, commercially available anchor coating agents include A-3210 / A-3070, A-3210 / A3072, A-3210 / A-3075 (all manufactured by Mitsui Chemicals, Inc.), Sequadine 2710A / Sequadine 2810C(T), Sequadine 2730A / Sequadine 2730B, Sequadine 2710A / Sequadine 2710C (all manufactured by Dainichi Seika Kogyo Co., Ltd.), DeckDry LX-500, DeckDry LX-901, and DeckDry LX747A (all manufactured by DIC Graphics Inc., DeckDry is a registered trademark of DIC Graphics Inc.).

[0030] (An adhesive used as needed in the dry lamination process) When the laminate layer of the fragrance-retaining laminate of the present invention is formed by extrusion dry lamination, the adhesive used as needed can be any laminating adhesive that has been conventionally used in the manufacture of composite laminate films for packaging, such as urethane resin-based, imino group-containing resin-based, or butadiene resin-based adhesives. Among these, urethane resin adhesives are preferred. Two-component adhesives can be used, consisting of a combination of an isocyanate-terminated urethane prepolymer made of a polyol component and an excess of aliphatic polyisocyanate component, and a polyol component, or a two-component adhesive consisting of a hydroxyl-terminated urethane prepolymer made of an excess of a polyol component and an aliphatic polyisocyanate component, and a polyisocyanate component. Epoxy compounds and silane coupling agents may also be included as needed.

[0031] Examples of commercially available adhesives include DeckDry LX-401A, 75A, 719, 703VL, 500, 510, etc. (all manufactured by DIC Graphics, DeckDry is a registered trademark of DIC Graphics), Takelac / Takenate A-969 / A-5, A-977 / A-92, A-606 / A-50, A-515 / A-50, A-626 / A-50, A-525 / A-52, A-666 / A-65, etc. (all manufactured by Mitsui Chemicals, Inc.), and RU-77, 771, 3600, 3900, etc. (all manufactured by Rock Paint Co., Ltd.).

[0032] (Printing layer) Even if dry lamination and extrusion lamination are not used, and even if there is no sealant layer or no laminate layer is formed, the aroma-retaining laminate of the present invention may have a printed layer. The printed layer can be obtained by printing using gravure printing, flexographic printing, or the like. As described above, in the front-printing method, the printed layer of printing ink is provided on the surface that will be the outside when processed into a container, and in the back-printing method, the printed layer of printing ink is provided on the surface that will be the inside when processed into a container. The order in which the fragrance-retaining coating composition layer and the printing layer are applied to the substrate layer can be determined arbitrarily. However, in order to obtain a uniform fragrance-retaining coating composition layer, it is preferable to apply the fragrance-retaining coating composition layer to the surface of the substrate layer.

[0033] (Other functional layers) Furthermore, the laminate of the present invention may have one or more functional layers between the base film and the sealant film for purposes such as improving gas barrier properties and reinforcing strength. Examples of such functional layers include vapor-deposited layers of silica, alumina, or metal or other resin layers for improving gas barrier properties such as oxygen, stretched nylon film layers for improving the strength reinforcement of the laminated film, and nylon-based metaxylenediamine resin film layers for improving both of the above functions. These various functional layers can be formed by vapor deposition onto any layer, coating formation, film lamination, etc. The laminate of the present invention may or may not have a layer made of ethylene-vinyl alcohol copolymer, polyvinyl alcohol, or polyamide, an inorganic compound layer such as a metal layer or a metal oxide layer, or a layer containing a metal-containing pigment.

[0034] (Applications of the laminate of the present invention) The laminate of the present invention is used in containers such as bags for airtight packaging of solid or liquid products containing aroma components, such as coffee powder, coffee beans, and tea leaves (including foods with added flavorings), as well as cosmetics, detergents, shampoos, and conditioners. To achieve this, the laminate is sealed by heating or other means between the sealant layers, thereby sealing the packaged product and preventing even the aroma components from being released outside the container. Therefore, when the laminate of the present invention is used in a container that can be airtightly sealed, it is possible to prevent the fragrance from leaking out of the container by allowing the fragrance components to penetrate or permeate at least the laminate of the present invention. Furthermore, by providing another layer in the laminate to prevent the permeation of, for example, oxygen, carbon dioxide, or water, it is possible to achieve both the prevention of fragrance component permeation and the prevention of oxygen, carbon dioxide, and water permeation in the laminate as a whole. It may also have a layer to block ultraviolet rays. Laminates having these layers can protect, seal, and package their contents without having a metal layer or metal oxide layer. Furthermore, it can be used to package contents that previously required a metal layer or similar to prevent the permeation of fragrance components. The form of the container using the laminate of the present invention is not particularly limited. The laminate of the present invention may be used for the entire container, or it can be used as a component such as a lid that adheres tightly to a container body having aroma-retaining properties, such as a bag, glass container, or resin injection molded or extruded product.

[0035] (Fragrance components) The fragrance components whose permeation is prevented by the layer formed by the fragrance-retaining coating composition of the present invention are the fragrance components contained in the above-mentioned solids or liquids that are packaged in containers formed using the packaging material having this layer. Such fragrance components include fragrance components derived from raw materials used to obtain the solid or liquid (for example, if the solid or liquid is a food product, these may include spices, meat, vegetables, fruits, fish, dairy products, seasonings, oils, etc.), as well as natural and synthetic fragrance components added during the manufacturing of products such as food products, fabric softeners, liquid detergents, shampoos, conditioners, antiperspirants, wet wipes, cosmetics, air fresheners for rooms and cars, and scented stationery, for the purpose of adding fragrance. Furthermore, the definition is not limited to the fragrance components of these items. Furthermore, preventing the permeation of aromatic components does not necessarily mean preventing the permeation of substances other than aromatic components, such as oxygen and nitrogen. [Examples]

[0036] <Fabrication of laminates> (Examples 1-11 and Comparative Examples 1-5) A base layer of either OPP (biaxially oriented polypropylene film (P2161, 25 μm thick, Toyobo Co., Ltd.)) or MDOPE (uniaxially oriented polyethylene film (PE3K-H, 25 μm thick, Futamura Chemical Co., Ltd.)) was prepared. The coating compositions of the examples and comparative examples were then applied using a wire bar and dried. In Example 2, MDOPE was used as the substrate, while OPP was used in the other examples and comparative examples. The above post-drying application amounts are 1.0, 0.5, 0.2, and 0.1 g / m². 2 To achieve this, the compositions of the examples and comparative examples shown in Tables 1 to 3 were diluted in advance with the solvents listed in the corresponding tables before the above coating was performed. After coating the sample, it was aged at 40°C for 3 days. Then, adhesive (Takelac A-969 / Takenate A-5 (Mitsui Chemicals, Inc.), 30% solids) was applied to the coated surface of the above-mentioned coating composition, and dried using a wire bar, with a coating amount of 3.0 g / m². 2 It was applied in this manner. The results for Examples 1-11 and Comparative Examples 1-5 below show that the coating amount after drying was 1.0 g / m². 2 This is the result under those conditions. However, the same result was obtained regardless of the amount of coating used as described above.

[0037] To the adhesive-coated surface, CPP (unoriented polypropylene film (P1128, 25 μm thick, Toyobo Co., Ltd.)) or LLDPE (unoriented polyethylene film of linear low-density polyethylene (Unilux LS-711C, 50 μm thick, Idemitsu Unilux Co., Ltd.)) was laminated, and each laminate was obtained by aging at 40°C for 3 days. In Example 2, LLDPE was laminated. In the other examples and comparative examples, the above-mentioned CPP was laminated. The resulting laminate was subjected to measurements of its aroma retention, oxygen barrier properties, and peel strength.

[0038] (Examples 12-18) In Example 1 described above, a layer made of a fragrance-retaining coating composition (coating layer) was sequentially provided with a blue ink layer and an adhesive layer, and the above-mentioned CPP was applied to the adhesive surface, which was designated as Example 12. Similarly, a layer made of a fragrance-retaining coating composition was sequentially provided with a white ink layer and an adhesive layer, and the above-mentioned CPP was applied to the adhesive surface, which was designated as Example 13. A layer made of a blue ink layer, a layer made of a fragrance-retaining coating composition, and an adhesive layer were sequentially provided on a substrate layer, and the above-mentioned CPP was applied to the adhesive surface, which was designated as Example 14. Furthermore, the same example as in Example 1 was designated as Example 15, and the amount of the layer consisting of the fragrance-retaining coating composition applied to Example 15 was set to 0.5 g / m². 2 , 0.2g / m 2 , 0.1g / m 2 Examples of the modified versions are designated as Examples 16 to 18.

[0039] Materials used in the examples and comparative examples, as well as their glass transition temperature (Tg) and hydroxyl value. Elitel UE-9800: Polyester resin (Unitika Corporation) Tg: 85℃, Hydroxyl value 4mgKOH / g, Acid value 3mgKOH / g, Viscosity average molecular weight 13000 Elitel UE-9200: Polyester resin (Unitika Corporation) Tg: 65℃, Hydroxyl value 6mgKOH / g, Acid value 1mgKOH / g, Viscosity average molecular weight 15000 DYNAPOL L912: Polyester resin (EVONIK) Tg: 105℃, Hydroxyl value 5mgKOH / g, Acid value 3mgKOH / g, Number average molecular weight 15000 Pluscoat RZ-105: Hydroxyl group-containing polyester resin (Go-o Chemical Co., Ltd.) Tg: 53℃, Hydroxyl group value unknown, Acid value 5 mg KOH / g

[0040] Nichigo Polyester LP-033: Polyester resin (Mitsubishi Chemical Corporation) Tg: 15℃, hydroxyl value 4-8 mg KOH / g Nichigo Polyester LP-035: Polyester resin (Mitsubishi Chemical Corporation) Tg: 20℃, hydroxyl value 2-8 mg KOH / g TEGOVariPlus CA: Ketone-aldehyde resin (EVONIK) Tg: 70℃, hydroxyl value 110 mg KOH / g Kuraray Poval 5-98: Polyvinyl alcohol resin (Kuraray Co., Ltd.) Tg unknown, hydroxyl value unknown Duranate 24A-90E: HDI-Biuret (Asahi Kasei Corporation), Tg unknown, no hydroxyl groups. Takenate D-110N: XDI-TMP adduct (Mitsui Chemicals, Inc.) Tg unknown, no hydroxyl groups. Desmodur ultra Z4470BA: IPDI-isocyanurate (Sumika Covestro Co., Ltd.), Tg unknown, no hydroxyl group. MEK: Methyl ethyl ketone IPA: Isopropyl alcohol Blue ink: Bellflora R Blue 800 (Sakata Inx Co., Ltd.) White ink: Bellflora R White 115 (Sakata Inx Co., Ltd.)

[0041] <Fragrance retention test method> The laminate described above was cut into 7cm squares, and one side was folded in half, with the long and short sides heat-sealed. The contents were then placed in the following: curry powder (1g) or coffee powder (1g), or fabric softener (4g) or liquid shampoo (4g), and the remaining side was heat-sealed. The prepared pouches were placed in glass bottles and sealed, and the leakage of fragrance after storage at 40°C for 7 days was evaluated as follows. Five testers skilled in fragrance evaluation checked the fragrance atmosphere inside the glass bottles and judged according to the following criteria. The table below shows the amount of fragrance leakage that was evaluated as being most highly by the testers.

[0042] Curry powder: Red can curry powder (S&B Foods Co., Ltd.) Coffee powder: Blendy Instant Coffee (Ajinomoto AGF Co., Ltd.) Fabric softener: Soflan Aroma Rich Sweet Floral Aroma scent (LION Corporation) Liquid Shampoo: Pantene Effortless Complete Night Repair Shampoo (P&G) ◎: No fragrance leakage ○: Slight fragrance leakage present. △: Scent leakage present ×: Strong scent leaking out.

[0043] <Method for evaluating oxygen barrier properties> The oxygen permeability (OTR value) of each laminate was measured using an oxygen permeability analyzer (Mocon, product name: OX-TRAN1 / 50) in accordance with JIS K7126 Method B. The measurements were performed at 25°C in a 0% RH atmosphere. ○: 100cc / m 2 Less than 1 day at a meter ×: 100cc / m 2 ·day · atm or more

[0044] <Method for evaluating laminate strength> Each laminate was cut into 15 mm wide strips, and the T-type peel strength (N / 15 mm) was measured using a peel tester (manufactured by Yasuda Seiki Seisakusho Co., Ltd.) as the peel strength.

[0045] [Table 1]

[0046] [Table 2]

[0047] [Table 3]

[0048] [Table 4]

[0049] According to the above examples, when curry powder, coffee powder, fabric softener, or shampoo was sealed in a packaging bag with a layer made of the fragrance-retaining coating composition of the present invention, the fragrances did not escape from the packaging bag, confirming that the coating possessed fragrance-retaining properties. However, the oxygen barrier properties were insufficient in these examples. This indicates that there is no direct correlation between excellent fragrance retention and the degree of oxygen barrier properties. Furthermore, the fragrance retention properties did not change even when an ink layer was provided in the laminate. The coating amount of the layer made of the fragrance-retaining coating composition was 0.5 g / m². 2 , 0.2g / m 2 , 0.1g / m 2 As the amount decreases, the aroma retention tends to decrease, but 0.1g / m 2 Even so, it was within acceptable limits. In contrast, Comparative Examples 1-3 employed coating compositions containing resins with low glass transition temperatures, and Comparative Examples 1 and 2, in particular, did not use a curing agent. Furthermore, Comparative Examples 4 and 5 were examples using ketone-aldehyde resins and polyvinyl alcohol resins, respectively. Comparative Examples 1-4 showed poor fragrance retention in the laminates. Comparative Example 5, on the other hand, showed excellent gas barrier properties but poor fragrance retention.

Claims

1. A fragrance-retaining coating composition containing a hydroxyl group-containing polyester resin with a glass transition temperature in the range of 40 to 120°C, and a solvent.

2. Furthermore, the fragrance-retaining coating composition according to claim 1 further contains a polyisocyanate curing agent as a curing agent.

3. The fragrance-retaining coating composition according to claim 2, wherein the polyisocyanate curing agent is a trifunctional or more isocyanate curing agent.

4. A laminate having at least a base layer, a layer made of the fragrance-retaining coating composition described in claim 1 or 2, and a heat-seal layer.

5. The amount of the layer made of the fragrance-retaining coating composition after drying is 0.15 to 1.0 g / m². ２ The laminate according to claim 4, which is within the range of claim 4.

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