JP2008110764A - Aerosol container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an aerosol container which can firmly and effectively protect the internal surface of the container body by generating no deterioration of a content liquid, and can provide an excellent corrosion-resistance performance when a stock solution containing a specified component and having a pH of 3.0 to 5.0 is housed together with a jetting agent in the metallic container body in use. <P>SOLUTION: The aerosol container 10 stores the stock solution including an organic acid, a surfactant, and a liquid oil and having a pH at 25°C of 3.0 to 5.0 in the metallic container body 11 together with the jetting agent, and this aerosol container discharges the housed liquid under a foam form from a dispensing section 15. The internal surface of the container body 11 is covered with an internal bag 12 consisting of a base layer 16, an EVOH layer 17 and a water-resistant resin layer 18. In this case, the base layer 16 consists of a polyolefin based resin such as a linear low density polyethylene. The EVOH layer 17 covers the base layer 16 from the internal side, and consists of a saponified ethylene-vinylacetate copolymer. The water-resistant resin layer 18 covers the EVOH layer 17 from the internal side, and consists of a polyolefin-based resin such as a linear low-density polyethylene. The stock solution preferably is the stock solution of a hair agent. <P>COPYRIGHT: (C)2008,JPO&INPIT

Description

  The present invention relates to an aerosol container, and more particularly, to an aerosol container in which a stock solution is accommodated in a metal container body together with a propellant, and the accommodated liquid is discharged in a foam form from a discharge portion.

  Aerosol containers are known as containers that contain hair agents, cosmetics, deodorants, insecticides, etc., and discharge the contained liquid in a mist-like, foam-like state from a discharge part provided on the mountain cup. . Some aerosol containers are made of plastics, but in many cases they are made of metal to maintain strength, and especially those that are commercialized in large sizes (with an internal volume of 100 ml or more) are legally regulated. And all are made of metal. In addition, the aerosol container is mounted with an inner bag containing the stored liquid inside a metal container body made of an aluminum plate, a steel plate, or the like, and between the inner bag and the container body, compressed gas, liquefied petroleum gas, etc. Of the type in which the inner bag is shrunk by the pressure of this propellant and the contained liquid is discharged, and the stock solution of hair, cosmetics, deodorant, insecticide and the like inside the container body It is roughly classified into a type in which a liquefied petroleum gas such as butane or propane or a propellant typified by dimethyl ether is filled and the stock solution is discharged in the form of foam by the action of the propellant.

  Normally, in an aerosol container in which the stock solution is filled with the propellant inside the container body, the stock solution directly touches the inside surface of the container body. For example, a method in which coating is performed by spray coating using a paint composed of, for example, an epoxy-amino system, an epoxy-phenol system, and a polyamide-imide system is generally employed.

Also, for example, when the containing liquid is strongly acidic or alkaline, or when it is a special one such as a hair dye containing a dye, for example, on one surface of an aluminum plate that is a forming material of the container body. A composite film in which a polyethylene or polypropylene resin layer is laminated on both sides of a vinylidene chloride resin layer is coated with an acid-modified polyolefin resin, and an aluminum plate or the like coated with the composite film is coated on the inner side of the container body. A technique is disclosed in which the inner side surface of the container body can be protected more firmly by forming an aerosol container by drawing while being disposed (see, for example, Patent Document 1). Furthermore, there is also a corrosion-resistant aerosol container in which an inner bag composed of a single layer such as a polyolefin resin or an inner bag composed of a multilayer of a polyolefin resin and a barrier resin is adhered to the inner surface of the container body. It is disclosed (for example, see Patent Document 2).
Japanese Patent Laid-Open No. 10-24973 JP 2003-170977 A

  When an undiluted solution containing an organic acid, a surfactant, and a liquid oil and having a pH of 3.0 to 5.0 at 25 ° C. is contained together with a propellant, the activity is high. However, it will corrode due to slight pinholes. Therefore, it is conceivable to provide an inner bag and store the stock solution together with the propellant therein.

  In the aerosol container which improved the corrosion resistance by covering the inner surface of the container body and arranging the inner bag, in view of its ease of manufacture, it is excellent in moldability and workability, and is flexible and after molding It is preferable to use an inner bag formed using a polyolefin resin having a low degree of crystallinity such as linear low density polyethylene (L-LDPE) as a resin that can easily maintain the shape.

  That is, the inner bag formed using a polyolefin-based resin having a low crystallinity is provided inside the container body through the upper end opening to which the mountain cup is attached, for example, by providing a fold in the vertical direction and folding it along the fold. It can be easily inserted, and can be easily brought into close contact with the inner surface of the container main body by returning to the shape before being folded by putting the containing liquid.

  On the other hand, when an undiluted solution containing an organic acid, a surfactant, and a liquid oil and having a pH of 3.0 to 5.0 at 25 ° C. is contained in an aerosol container together with a propellant, the polyolefin resin is There is a possibility that the stored liquid may be altered by dissolving out due to the compatibility with the oil component containing the propellant in the stored liquid. Therefore, ethylene-vinyl acetate copolymer saponified product (EVOH) is used instead of polyolefin resin as a laminate material that can prevent leakage of propellant because it is not compatible with oil components and has excellent oxygen barrier properties. Although it is conceivable to use, EVOH monolayer lacks flexibility and is difficult to insert into the container body.

  Further, the present inventors made an inner bag with EVOH as an inner layer and a polyolefin resin as an outer layer in order to facilitate insertion into the container body, and an organic acid, a surfactant and a liquid were added to the inner bag thus created. Oil containing a stock solution having a pH of 3.0 to 5.0 at 25 ° C. was stored together with a propellant, and various performance tests were performed. After storing the solution for a long period of time, the stored solution was sprayed from an aerosol container. In this case, it was found that the properties of the foam changed.

  The present invention contains an organic acid, a surfactant, and a liquid oil, and contains a stock solution having a pH of 3.0 to 5.0 at 25 ° C. in a metallic container body together with a propellant. It was made with the intention of solving the above-mentioned technical problems peculiar to the aerosol container that discharges foam in the form of foam from the discharge part, and is a laminate material made of saponified ethylene-vinyl acetate copolymer (EVOH) The metallic aerosol container can be easily installed on the inner surface of the container body, and can effectively exhibit the function of the EVOH layer, so that the foam state hardly changes even when left for a long period of time. For the purpose.

  The present invention contains an organic acid, a surfactant, and a liquid oil, and contains a stock solution having a pH of 3.0 to 5.0 at 25 ° C. in a metal container body together with a propellant. An aerosol container that discharges foam from a discharge part, wherein the container body is made of metal, and the liquid container contains a base layer made of polyolefin resin, and an ethylene-vinyl acetate copolymer covering the base layer from the inside. The above object is achieved by providing an aerosol container housed in an inner bag having a fluoride (EVOH) layer and a water-resistant resin layer covering the saponified ethylene-vinyl acetate copolymer (EVOH) layer from the inside. It is a thing.

  As a result of various studies on the layer structure of the inner bag including the EVOH layer, the present invention provides an EVOH layer covering the inside of the base layer made of polyolefin resin, and covers the inside of the EVOH layer to form a water-resistant resin layer. When the aerosol container was provided, permeation of the liquid oil in the stock solution was not observed even when the aerosol container was left for a long period of time. The barrier function by the EVOH layer prevents the permeation of the liquid oil in the stock solution.

  Here, when the low molecular weight ratio of the water resistant resin constituting the water resistant resin layer is large, when a liquefied petroleum gas such as butane or propane is used as a propellant, the low molecular weight portion in the water resistant resin is eluted. It was found that a low molecular weight portion oozes out of the bag. It was also found that elution / adsorption occurred during the formulation, changing the properties of the foam. Accordingly, the low molecular weight ratio of the water-resistant resin is preferably as low as possible, and the ratio is preferably less than 1.4%, particularly preferably 1.0 to 0.5%.

  In addition, the low molecular weight ratio of the water-resistant resin constituting the water-resistant resin layer is a value (%) measured by the following decane extract measurement method defined by the extraction method. For example, the decane extract amount measured by the decane extract amount measurement method of linear low density polyethylene (trade name “GS-650”: manufactured by Nihon Unicar Co., Ltd.) used in Examples described later was 1.4%. . Further, for example, the decane extract amount measured by the decane extract amount measurement method of metallocene linear low density polyethylene (trade name “SP2530S”: manufactured by Prime Polymer Co., Ltd.) used in Examples described later is 0.5%. there were.

[Decane extraction amount measurement method]
1. The sample is immersed in decane and the temperature is increased at a constant rate (from room temperature (25 ° C.) to 145 ° C .; 2 hours).
Store at 2.145 ° C. for 2 hours.
3. Reduce the temperature at a constant rate (145 ° C to 80 ° C; 3 hours, 80 ° C to room temperature (25 ° C); 5 hours)
4). The mixture is filtered through a glass filter (glass filter Buchner funnel type: 25G-4, manufactured by Sakai Glass Tech Co., Ltd.), the filtrate is air-dried, and the weight of the residue is measured.
5. The amount of decane extracted is obtained by the following formula.
Decane extraction amount (%) = residue weight / sample weight × 100

  According to the aerosol container of the present invention, a stock solution containing an organic acid, a surfactant, and a liquid oil and having a pH of 3.0 to 5.0 at 25 ° C. is housed in a metallic container body together with a propellant. Even in this case, the inner side surface of the container body can be firmly and effectively protected to obtain excellent corrosion resistance, and stable foam performance can be obtained.

  As shown in FIG. 1 (a), an aerosol container 10 according to a preferred embodiment of the present invention has an inner bag 12 attached in close contact with an inner surface of a metal container body 11 made of, for example, an aluminum plate. In the container body 11 to which the inner bag 12 is attached, a stock solution such as a hair preparation, a cosmetic, a deodorant and an insecticide and a propellant represented by liquefied petroleum gas such as butane and propane, and dimethyl ether are used. The container is a container that contains the mixture as a storage liquid and discharges the storage liquid in a foam form from a discharge portion 15 provided in a mountain cup 14 that is attached to cover the upper end opening 13 of the container body 11.

  And in this embodiment, the undiluted | stock solution accommodated in the container main body 11 with a propellant as an accommodating liquid contains an organic acid, surfactant, and liquid oil, and pH in 25 degreeC is 3.0-5. As shown in FIGS. 1 (b) and 1 (c), an inner bag 12 that is a zero stock solution and covers the inner surface of the container body 11 includes a base layer 16 made of polyolefin resin and ethylene-acetic acid that covers the base layer 16 from the inside. An EVOH layer 17 made of a saponified vinyl copolymer (EVOH) and a water-resistant resin layer 18 made of a water-resistant resin that covers the EVOH layer 17 from the inside are included.

  In this embodiment, examples of the organic acid constituting the stock solution include monocarboxylic acid, dicarboxylic acid, hydroxycarboxylic acid, and polycarboxylic acid. Of these, dicarboxylic acids and hydroxycarboxylic acids (particularly α-hydroxycarboxylic acids) are particularly preferable. Examples of the dicarboxylic acid include malonic acid, succinic acid, glutaric acid, adipic acid, maleic acid, fumaric acid, and phthalic acid, and maleic acid is particularly preferable. Examples of the hydroxycarboxylic acid include glycolic acid, lactic acid, hydroxyacrylic acid, malic acid, tartaric acid, and citric acid, and malic acid, malic acid, and a mixture of lactic acid are particularly preferable.

  These organic acids may be used in combination of two or more, and when the stock solution is a hair preparation, the content of the stock solution is from the point of hair modification effect, set-holding improvement effect, group improvement effect, etc. The content is preferably 0.001 to 20% by mass, more preferably 0.005 to 15% by mass, and particularly preferably 0.01 to 10% by mass.

  The surfactant constituting the stock solution is used for improving the solubilizing ability and foaming property. Surfactants include alkyl benzene sulfonates, alkyl or alkenyl ether sulfates, alkyl or alkenyl sulfates, olefin sulfonates, alkane sulfonates, saturated or unsaturated fatty acid salts, alkyl or alkenyl ether carboxylates, α -Sulfone fatty acid salts, N-acylamino acid type surfactants, phosphate mono- or diester type surfactants, sulfosuccinate ester and other anionic surfactants; imidazoline series, carbobetaine series, amide betaine series, sulfobetaine series, hydroxy Amphoteric surfactants such as sulfobetaine and amidosulfobetaine amphoteric surfactants; polyoxyalkylene alkyl ethers, polyoxyalkylene alkenyl ethers, higher fatty acid sucrose esters, polyglycerin fatty acid esters, higher fatty acid monomers Nonionic surfactants such as ethanolamide or diethanolamide, polyoxyethylene hydrogenated castor oil, polyoxyethylene sorbitan fatty acid ester, polyoxyethylene sorbit fatty acid ester, alkyl saccharide surfactant, alkylamine oxide, alkylamidoamine oxide; imidazoline Examples thereof include cationic surfactants such as ring-opening type quaternary ammonium salts, quaternary ammonium salts, mono long chain alkyl quaternary ammonium salts, and di long chain alkyl quaternary ammonium salts.

  The liquid oil constituting the stock solution is not particularly limited as long as it is liquid at normal temperature and is usually used for cosmetics, etc., regardless of animal oil, vegetable oil, mineral oil, synthetic oil, hydrocarbons, esters Silicone oils, fluorine-based oils, and the like can be used. Specifically, hydrocarbons such as liquid paraffin, squalane and polybutene, castor oil, macadamian nut oil, olive oil, avocado oil, safflower oil, sunflower oil, jojoba oil, mink oil and other fats, lanolin such as lanolin acetate , Esters such as isopropyl myristate, isopropyl palmitate, octyldodecyl myristate, cetyl 2-ethylhexanoate, isocetyl stearate, pentaerythritol fatty acid esters, triglyceryl 2-ethylhexanoate, diglyceryl triisostearate, etc. Glycerin fatty acid esters, higher alcohols such as oleyl alcohol and hexadecyl alcohol, silicone oils such as dimethylpolysiloxane and methylphenylpolysiloxane, and fluorine-based oils such as perfluorodecane.

  In the case where the stock solution is a hair preparation, among these, in order to obtain good gloss and spread, lubricity, an appropriate drying speed and non-stickiness at the time of drying, those of 500 mPa · S or less are preferable. , Silicone oils such as dimethylpolysiloxane and methylphenylpolysiloxane, which have a high effect of imparting lubricity, isopropyl myristate, isopropyl palmitate, octyldodecyl myristate, cetyl 2-ethylhexanoate with high penetrability to hair, A combination of two or more liquid oils selected from esters such as isocetyl stearate and hydrocarbons such as liquid paraffin and squalane is more preferable.

  In the present embodiment, the stock solution may further contain an organic solvent selected from the following (i) to (v).

(I) Aromatic alcohol represented by the following general formula (1) (ii) N-alkylpyrrolidone having a C1-C18 alkyl group bonded to a nitrogen atom (iii) C2-C4 alkylene carbonate (iv ) Polypropylene glycol having an average molecular weight of 100 to 1000 (v) Lactone or cyclic ketone represented by the following general formula (2), (3) or (4)

[Wherein R ¹ represents a group R ² —Ph—R ³ — (R ² ; a hydrogen atom, a methyl group or a methoxy group, R ³ ; a bond or a saturated or unsaturated divalent carbon atom having 1 to 3 carbon atoms. Hydrogen group, Ph; paraphenylene group), at least one of Y and Z represents a hydroxyl group, the remainder represents a hydrogen atom, and p, q, and r represent integers of 0 to 5. ]

[Wherein, X represents a methylene group or an oxygen atom, and R ⁴ and R ⁵ independently represent a linear, branched or cyclic carbon which may be substituted by a sulfonic acid group, a phosphoric acid group or a carboxy group. A substituent selected from an alkyl group, a hydroxyl group, a sulfonic acid group, a phosphoric acid group, a carboxy group, and a phenyl group represented by Formulas 1 to 10 is shown. ]

Among organic solvents, (i) includes benzyl alcohol, cinnamyl alcohol, phenethyl alcohol, p-anisyl alcohol, p-methylbenzyl alcohol, phenoxyethanol, 2-benzyloxyethanol and the like. Examples of (ii) include N-methylpyrrolidone, N-octylpyrrolidone, N-laurylpyrrolidone and the like. Examples of (iii) include ethylene carbonate and propylene carbonate. As (iv) polypropylene glycol having an average molecular weight of 100 to 1000, those having an average molecular weight of 200 to 500 are preferable. In (v), R ⁴ and R ⁵ in general formulas (2) to (4) are linear, branched or cyclic alkyl groups, hydroxyl groups, sulfonic acid groups, phosphoric acid groups, carboxy groups, and phenyl groups. , A sulfoalkyl group, an alkyl phosphate group, a carboxyalkyl group, etc. are preferable. In particular, in the case of γ-lactone, the γ-position is substituted, and in the case of δ-lactone, the δ-position (that is, the methylene adjacent to the hetero oxygen atom) is substituted. C1-C6 linear or branched alkyl groups such as methyl, ethyl, propyl, isopropyl and butyl groups are preferred. In addition, when it is desired to increase the water solubility of the compounds (2) to (4), R ⁴ or R ⁵ has an acidic group such as a sulfonic acid group, a phosphoric acid group or a carboxy group, or an alkyl group substituted with these. Is preferred. Among (v), examples of the lactone include γ-butyrolactone, γ-caprolactone, γ-valerolactone, δ-valerolactone, δ-caprolactone, δ-heptanolactone, and the like, from the viewpoint of lactone stability. Γ-lactone, particularly γ-butyrolactone and γ-caprolactone are preferred. Among (v), examples of the cyclic ketone include cyclopentanone, cyclohexanone, cycloheptanone, and 4-methylcycloheptanone.

  In particular, benzyl alcohol, benzyloxyethanol, propylene carbonate, and polypropylene glycol (number average molecular weight 300 to 500, particularly 400) are preferable.

Further, the organic solvent needs to have ClogP of −2 to 3, and is preferably −1 to 2 from the viewpoint of promoting penetration. Here, ClogP is a calculated value of the octanol-water-partition coefficient (logP) defined by the following formula, which is a measure representing the distribution of substances between the octanol phase and the water phase. An example is described in Vol. 71, No. 6 (1971).
logP = log ([Substance] _Octanol / [Substance] _Water )
[In the formula, [Substance] _Octanol represents the molar concentration of the substance in the 1-octanol phase, and [Substance] _Water represents the molar concentration of the substance in the aqueous phase. ]

  Specifically, ClogP of the main organic solvents is benzyl alcohol (1.1), 2-benzyloxyethanol (1.2), 2-phenylethanol (1.2), 1-phenoxy-2-propanol (1.1), polypropylene glycol 400 (0.9), propylene carbonate (-0.41), and γ-butyrolactone (-0.64).

  The organic solvent is preferably a liquid at 25 ° C., and two or more kinds may be used in combination. The content of the organic solvent is a feeling of use, a gloss of hair and a modification effect when the stock solution is a hair preparation. From the point of promotion of (improvement of elasticity, improvement of moisture resistance, etc.), 0.1 to 40% by weight in the stock solution is preferable, further 0.5 to 10% by weight, particularly 1 to 5% by weight is preferable. Furthermore, in order to promote the hair modification effect, the weight ratio of the organic solvent to the organic acid is preferably 5: 1 to 1: 2, particularly 3: 1 to 2: 1.

  In this embodiment, when the stock solution is a hair preparation, from the viewpoint of further improving hair styling, adjusting viscosity, stability, improving adhesion when applying hair, improving touch, and early expression of hair modification effects. The set polymer may be contained in the stock solution. Such polymers include polyvinylpyrrolidone, vinylpyrrolidone / vinyl acetate copolymer, vinylpyrrolidone / vinyl acetate / vinyl propionate terpolymer, vinylpyrrolidone / alkylaminoacrylate (quaternary chloride) copolymer, vinyl Polyvinyl pyrrolidone polymer compounds such as pyrrolidone / acrylate / (meth) acrylic acid copolymer, vinyl pyrrolidone / alkylamino acrylate / vinyl caprolactam copolymer; acidic vinyl ether such as methyl vinyl ether / alkyl maleic anhydride alkyl half ester copolymer Polymer compounds; acidic polyvinyl acetate polymer compounds such as vinyl acetate / crotonic acid copolymer, vinyl acetate / crotonic acid / vinyl neodecanoate copolymer, vinyl acetate / crotonic acid / vinyl propionate copolymer; Acid acrylic polymer such as (meth) acrylic acid / (meth) acrylic acid ester copolymer, acrylic acid / acrylic acid alkyl ester / alkylacrylamide copolymer; N-methacryloylethyl-N, N-dimethylammonium α Amphoteric acrylic polymer compounds such as -N-methylcarboxybetaine / butyl methacrylate copolymer, hydroxypropyl acrylate / butylaminoethyl methacrylate / octylamide copolymer; acrylamide / acrylic ester quaternary Examples thereof include basic acrylic polymer compounds such as polymers; cellulose derivatives such as cationic cellulose derivatives; chitin / chitosan derivatives such as hydroxypropyl chitosan, carboxymethyl chitin, and carboxymethyl chitosan.

  These set polymers can be used alone or in combination of two or more, and the content thereof is 0.1 to 10% by mass, particularly 0.5 to 5% by mass in the hair cosmetic composition of the present invention. % Is preferred.

  When the stock solution is a hair cosmetic agent, in addition to the above components, components used in normal hair cosmetics can be appropriately blended depending on the purpose. Examples of such components include anti-dandruff agents; vitamin agents; bactericides; anti-inflammatory agents; antiseptics; chelating agents; moisturizers such as sorbitol and panthenol; colorants such as dyes and pigments; hydroxyethyl cellulose, methyl cellulose, Viscosity modifiers such as polyethylene glycol and clay minerals; pH modifiers such as organic acids other than component (A), sodium hydroxide, potassium hydroxide; plant extracts; pearling agents; fragrances; dyes; Inhibitors; and other components described in ENCYCLOPEDIA OF SHAMPOO INGREDIENTS (MICELLE PRESS).

  In this embodiment, the stock solution containing the above-described components is adjusted such that the pH value at 25 ° C. is 3.0 to 5.0 when diluted 20 times by weight with water, for example. Moreover, when the undiluted | stock solution is a hair agent, it is preferable that the pH value in 25 degreeC is 2.5-4.0 from a viewpoint of hair modification | reformation (gloss, unity), and 3.0-4. Particularly preferred is 0.

  In the present embodiment, examples of the propellant accommodated in the container body 11 together with the stock solution include liquefied petroleum gas (LPG), dimethyl ether (DME), carbon dioxide gas, nitrogen gas, and a mixture thereof. Of these, liquefied petroleum gas (LPG) and dimethyl ether (DME) are preferred. Alternatively, alternative chlorofluorocarbons such as HFC-152a can be used. The amount of the propellant is a mass ratio of the stock solution and the propellant, and the stock solution: propellant = 40: 60 to 99: 1, particularly 90:10 to 95: 5 is preferable. Moreover, it is preferable to adjust so that the pressure in a pressure vessel may be set to 0.15-0.55 MPa at 25 degreeC.

  And in this embodiment, as shown in FIG.1 (b), (c), the inner bag 12 with which it mounts | wears with the inner surface of the container main body 11, and the accommodation liquid which consists of a stock solution and a propellant is accommodated. A base layer 16 made of polyolefin-based resin, an EVOH layer 17 made of saponified ethylene-vinyl acetate copolymer (EVOH) covering the base layer 16 from the inside, and a water-resistant resin layer made of a water-resistant resin covering the EVOH layer 17 from the inside 18 and so on.

  As the polyolefin resin constituting the base layer 16 of the inner bag 12, a polyolefin resin having a low crystallinity is preferably used as a resin that is excellent in moldability and workability, is flexible, and easily maintains the shape after molding. be able to. Examples of polyolefin resins having low crystallinity include linear low density polyethylene (L-LDPE), metallocene linear low density polyethylene (metallocene L-LDPE), and medium density polyethylene (MDPE). It is particularly preferable to use L-LDPE from the viewpoints of properties and costs.

  The neck thickness t2 is preferably 200 to 300 [mu] m, particularly preferably 220 to 280 [mu] m, of the base layer 16 made of polyolefin resin. Furthermore, the thickness t1 of the body portion is preferably 80 to 200 μm, particularly preferably 120 to 180 μm, for the base layer 16 made of polyolefin resin. If the thickness of the base layer 16 at the neck is larger than 300 μm, the mountain cup is not properly mounted at the time of valve clinching, resulting in a problem of abnormal leakage. If the thickness of the base layer 16 at the neck is smaller than 200 μm, the flange of the neck Will cause wrinkles and a problem of abnormal leakage. Further, when the thickness of the base layer 16 at the neck is 220 to 280 μm, the valve can be mounted under normal clinching conditions.

  The EVOH constituting the EVOH layer 17 of the inner bag 12 is laminated by covering the base layer 16 made of polyolefin resin from the inside in order to prevent leakage of the propellant accommodated together with the stock solution.

  Further, the EVOH layer 17 preferably has a neck thickness t2 of 20 to 120 [mu] m, particularly preferably 60 to 90 [mu] m. Further, the thickness t1 of the body portion is preferably 20 to 90 μm, particularly preferably 30 to 80 μm. If the thickness of the EVOH layer 17 on the trunk is larger than 120 μm, the rigidity of the inner bag becomes strong, resulting in a problem of poor insertion into the can. If the thickness is smaller than 20 μm, the barrier property is The trouble that an effect cannot be exhibited will arise. Further, when the thickness of the EVOH layer 17 in the body portion is 30 to 80 μm, there is an effect of barrier performance and an advantage of preventing the oil agent from exuding can be obtained.

  The water resistant resin constituting the water resistant resin layer 18 of the inner bag 12 is such that EVOH laminated on the inner side of the base layer 16 made of polyolefin resin comes into contact with the liquid contained in the container body and has a barrier property against the propellant. In order to prevent the lowering of the EVOH layer, the EVOH layer 17 is laminated from the inside. Examples of the water resistant resin include linear low density polyethylene (L-LDPE), metallocene linear low density polyethylene (metallocene L-LDPE), and medium density polyethylene (MDPE). From the viewpoint of insertability into the can, it is desirable to cover the EVOH layer 17 with the same material as the base layer 16, but it is also possible not to use the same material as the base layer 16.

  The water-resistant resin layer 18 made of water-resistant resin has the same thickness as the base layer 16, and the neck thickness t2 is preferably 200 to 300 [mu] m, particularly preferably 220 to 280 [mu] m. Further, the thickness t1 of the body portion is preferably 80 to 200 μm, and particularly preferably 120 to 180 μm. If the thickness of the water-resistant layer 18 at the neck portion is larger than 300 μm, the mountain cup is not properly mounted at the time of valve clinching, resulting in a problem of abnormal leakage, and if it is smaller than 200 μm, the neck flange becomes wrinkled and abnormal leakage occurs. A failure will occur. Further, when the thickness of the base layer 16 at the neck is 220 to 280 μm, the valve can be mounted under normal clinching conditions.

  In the present embodiment, the inner bag 12 having the above-described configuration is formed using a general-purpose known method for forming a multilayer film material made of a synthetic resin, and the EVOH and the water-resistant resin are the entire base layer 16 made of a polyolefin-based resin. And is easily formed into a three-dimensional shape along the inner surface of the container body 11. In addition, the inner bag 12 is provided with a fold-like pleat for making the insertion work easier by being contracted and deformed inward when the inner bag 12 is inserted and mounted inside through the upper end opening 13 of the container body 11. be able to. For example, the inner bag 12 is attached to the inside of the container main body 11 by pushing the inner bag 12 into the container main body 11 from the bottom side through the upper end opening 13 using an insertion rod.

  After mounting the inner bag 12, the mountain cup 14 is attached so as to cover the upper end opening 13 of the container body 11. Further, for example, an undiluted solution containing an organic acid, a surfactant, and a liquid oil and having a pH of 3.0 to 5.0 at 25 ° C. is stored together with a propellant through a discharge portion 15 provided in the mountain cup 14. The container body 11 is filled and contained as a liquid. In the present embodiment, the mountain cup 14 is formed of, for example, an aluminum material. However, by providing a laminated layer made of polyethylene terephthalate with a thickness of, for example, about 38 μm on the inside, the acid or interface contained in the stored liquid Corrosion due to the effects of activators is avoided.

  And the aerosol container 10 of this embodiment contains an organic acid, surfactant, and liquid oil, and is a container liquid which consists of a stock solution and a propellant whose pH at 25 degreeC is 3.0-5.0. For example, a styling hair foam agent that is a hair agent is accommodated, and the accommodated liquid is foamed and discharged from the discharge portion 15 provided in the mountain cup 14, for example, for about several months. According to the aerosol container 10 of this embodiment, an aluminum solution containing such an organic acid, a surfactant, and a liquid oil and having a pH of 3.0 to 5.0 at 25 ° C. together with a propellant is used. Even when accommodated in a metal container body 11 made of a plate, the inner surface of the container body 11 is protected firmly and effectively without changing the state of the injected foam, and excellent corrosion resistance is obtained. be able to.

  That is, according to the present embodiment, the inner bag 12 is mounted in a tight contact state (including a state in which a gap is partially left) covering the inner side surface of the metal container main body 11. The bag 12 includes a base layer 16 made of a polyolefin resin, an EVOH layer 17 that covers the base layer 16 from the inside, and a water-resistant resin layer 18 made of a water-resistant resin that covers the EVOH layer 17 from the inside. It can be effectively avoided that the inner surface of the container body 11 comes into contact with the inner surface and is corroded. Further, since the inside of the base layer 16 made of polyolefin resin is covered with the EVOH layer 17, the oil component in the stored liquid is blocked from coming into contact with the base layer 16, and the stored liquid is altered by elution of the polyolefin resin. Can be effectively avoided. Furthermore, since the inside of the EVOH layer 17 is covered with the water-resistant resin layer 18 made of a water-resistant resin, the stored liquid is blocked from coming into contact with the EVOH layer 17, and the leakage preventing function of the propellant by EVOH is reduced. Can be effectively avoided.

  The present invention is not limited to the above-described embodiment, and various modifications can be made. For example, the container body may be made of a metal made of other metal plates such as a steel plate other than an aluminum plate, and the container liquid stored in the container body is an organic acid other than a hair agent, Other containing liquids, such as cosmetics, deodorants, insecticides, etc., which contain a surfactant and liquid oil and consist of a stock solution and a propellant having a pH of 3.0 to 5.0 at 25 ° C. May be. The inner bag 12 has a three-layer structure including a base layer made of a polyolefin resin, an EVOH layer 17 that covers the base layer from the inside, and a water-resistant resin layer that covers the EVOH layer 17 from the inside, and other synthetic resin layers. It may be a four-layer structure or more.

Moreover, as a specific layer structure of the inner bag, the following can be preferably employed.
1. Outer) L-LDPE / adhesive olefin / EVOH / adhesive olefin / L-LDPE (inner 2. outer) MDPE / adhesive olefin / EVOH / adhesive olefin / MDPE (inner 3. outer) metallocene L-LDPE / adhesive olefin / EVOH / Adhesive olefin
/ Metallocene L-LDPE (inside

  EXAMPLES Hereinafter, although an Example and a comparative example demonstrate this invention further in detail, this invention is not limited to these.

[Example 1]
The aerosol container of Example 1 having substantially the same configuration as the aerosol container 10 of the above embodiment, wherein the layer structure of the inner bag is L-LDPE / adhesive olefin / EVOH / adhesive olefin / L-LDPE from the outside to the inside. In addition, it contains an organic acid, a surfactant, and a liquid oil, and contains a containing liquid consisting of a stock solution and a propellant having a pH of 3.0 to 5.0 at 25 ° C., and oozes out into the containing liquid. Were tested by the following method, and insertion into an aerosol container was determined. The test results are shown in Table 1. In addition, the product name “GS-650” (manufactured by Nihon Unicar Co., Ltd.) having a decane extraction amount of 1.4% was used as L-LDPE, with the A part thickness of the inner bag being 350 μm. Moreover, when mixing a slip agent, the mixing ratio of the slip agent in a masterbatch was 2 weight%.

[Example 2]
The structure of Example 2 which is provided with the structure substantially the same as the aerosol container 10 of the said embodiment, and the layer structure of the inner bag is metallocene L-LDPE / adhesive olefin / EVOH / adhesive olefin / metallocene L-LDPE from the outside to the inside. An aerosol container contains an organic acid, a surfactant, and a liquid oil, and contains a containing liquid composed of a stock solution and a propellant having a pH of 3.0 to 5.0 at 25 ° C. Exudation was tested by the following method, and insertion into an aerosol container was determined. The test results are shown in Table 1. In addition, the product name “SP2530S” (manufactured by Prime Polymer Co., Ltd.) having a decane extraction amount of 0.5% was used as the metallocene L-LDPE with the thickness of part A of the inner bag being 350 μm. Moreover, when mixing a slip agent, the mixing ratio of the slip agent in a masterbatch was 2 weight%.

[Comparative Example 1]
The aerosol container of Comparative Example 1 having substantially the same configuration as the aerosol container 10 of the above-described embodiment and equipped with an L-LDPE single layer (resin grade: GS-650) as an inner bag has an organic acid and an interface. Contains a storage liquid consisting of a stock solution and a propellant having an activator and liquid oil and a pH of 3.0 to 5.0 at 25 ° C., and tests for oozing into the storage liquid by the following method. At the same time, insertability into an aerosol container was determined. The test results are shown in Table 1. In addition, A part thickness of the inner bag was 350 micrometers. Moreover, when mixing a slip agent, the mixing ratio of the slip agent in a masterbatch was 2 weight%.

[Test method for exudation of stored liquid]
1. Fill the stock solution and propellant at a certain weight ratio with a set amount.
2. Store upright in a 45 ° C thermostat.
3. Evaluate every 1 month, 2 months, 3 months, and 6 months.
〔Evaluation methods〕
1. Confirmation of foam quality (sensory evaluation)
2. Can open evaluation (visual confirmation)
[Criteria]
1. Comparison with foam quality ... reference (room temperature storage product) Can open evaluation: Visual judgment of whether or not the inner wall of the opened can is exuded

  According to the test results shown in Table 1, the aerosol container of the present invention has good insertability of the inner bag and can easily install the EVOH layer on the inner surface of the container main body, and also includes an organic acid, a surfactant, and a liquid It is found that a good foamed state can be maintained for a long period of time by preventing exudation of the containing liquid composed of a stock solution and a propellant having a pH of 3.0 to 5.0 at 25 ° C. .

(A) is sectional drawing explaining the structure of the aerosol container which concerns on preferable one Embodiment of this invention, (b) is the A section expanded sectional view of (a) explaining the layer structure of an inner bag trunk | drum. . (C) is the B section expanded sectional view of (a) explaining the layer composition and shape of an inner bag neck.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Aerosol container 11 Container main body 12 Inner bag 13 Upper end opening 14 Mountain cup 15 Discharge part 16 Base layer 17 EVOH layer 18 Water resistant resin layer

Claims (5)

A stock solution containing an organic acid, a surfactant, and a liquid oil and having a pH of 3.0 to 5.0 at 25 ° C. is stored in a metal container body together with a propellant, and the stored liquid is discharged from the discharge unit. An aerosol container that discharges in foam,
The container body is made of metal, and the containing liquid is a base layer made of polyolefin resin, an ethylene-vinyl acetate copolymer saponified layer (EVOH) covering the base layer from the inside, and the ethylene-vinyl acetate copolymer sapon. The aerosol container accommodated in the inner bag containing the water resistant resin layer which consists of a water resistant resin which covers a chemical compound layer from the inside.   The aerosol container according to claim 1, wherein the polyolefin resin is linear low density polyethylene (L-LDPE) or medium density polyethylene (MDPE).   The aerosol container according to claim 1 or 2, wherein the water-resistant resin is linear low density polyethylene (L-LDPE) or medium density polyethylene (MDPE).   The aerosol container according to claim 1, wherein the stock solution is a stock solution of a cosmetic for hair.   The aerosol container according to any one of claims 1 to 4, wherein a low molecular weight ratio of the water-resistant resin is less than 1.4%.

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