JPH0436948B2 - - Google Patents

Description

[Detailed description of the invention]

(Industrial Application Field) The present invention relates to a container lid with a liner,
More specifically, the present invention relates to a liner-equipped container lid that includes a liner made of vinyl chloride plastisol and has excellent capping and opening properties. (Prior Art) In container lids such as caps and crowns, it is widely practiced to provide a sealing material such as a liner in order to ensure a tight seal with a container opening such as a bottle mouth. Plastisol, which is made by dispersing vinyl chloride resin particles in a plasticizer, can be applied to container lids of any shape in a fluid state, and can be easily formed into a sealing liner by heating and gelling. It is widely used in the formation of Sealing liners using vinyl chloride plastisol have excellent properties such as compressibility, elasticity, flexibility, cushioning properties, and gas barrier properties, but
Plastisol has poor lubricity, and to improve this, it is widely practiced to add a lubricant to plastisol. (Problems to be Solved by the Invention) However, vinyl chloride plastisols containing lubricants have not yet been satisfactory in terms of the combination of capping and opening properties and shelf life of the contents. In other words, when a container lid with a liner made from this plastisol is used to seal a bottled product, if the surface has little smoothness, the bottle opening will not be fully wedged into the liner during capping, and the lid will not be securely and sufficiently high. It becomes difficult to obtain sealing pressure. Further, even if the liner has capping properties, the opening torque of bottled products becomes abnormally high over time, and in extreme cases, there is a tendency that the bottle may be damaged. The surface smoothness of a liner formed from plastisol is imparted by the migration of the lubricant blended into the composition onto the surface; however, if this migration speed is too slow, poor capping properties may occur, and this If the migration speed is too fast, there will not be a sufficient amount of lubricant on the surface, resulting in poor opening. In order to solve this problem, plastisol contains a high concentration of lubricant, but in this case, the lubricant migrates to the contents, forming suspended particles of lubricant, and This lowers the commercial value of the product, gives consumers the impression that the quality of the product has deteriorated, and furthermore, the off-taste and odor caused by the lubricant actually transfers to the product, which is undesirable in terms of flavor retention. Therefore, an object of the present invention is to eliminate the above-mentioned drawbacks of conventional sealing liners made from vinyl chloride plastisol, and to provide a container lid with a liner that has excellent capping performance, opening performance, and preservation of contents. It is in. (Means for Solving the Problems) According to the present invention, vinyl chloride resin, plasticizer,
A liner-equipped container characterized by having a liner formed from a composition in which plastisol containing a lubricant and a stabilizer is blended with a plasticizer-insoluble organic polymer filler in an amount of 2 to 60% by volume per vinyl chloride resin. A lid is provided. In the present invention, the organic polymer filler has a maximum dimension of 2 to 1500 μm and an aspect ratio of 1 to 1500 μm.
1000 particles such as fibers or powders or flakes thereof, most preferably cellulose fiber powder. (Function) The liner of the present invention is formed from a plastisol containing a vinyl chloride resin, a plasticizer, a lubricant, and a stabilizer. ~40
This is based on the finding that when % by volume of a plasticizer-insoluble organic polymeric filler is incorporated, the liner formed has a combination of excellent capping properties, opening properties, and shelf life of the contents. FIG. 1 of the accompanying drawings shows the results of liners formed from various plastisols of the Examples described below and subjected to an accelerated aging test. These results show that the plastisol composition used in the present invention (Example 1) maintains the amount of lubricant on the liner surface almost constant over time, compared to conventional plastisol compositions (Comparative Examples 1 and 2). It can be seen that it has the characteristics of Therefore, with the liner of the present invention, excellent capping performance is obtained in the initial stage, and capping can be performed with sufficiently high sealing pressure, and even after sealing, there is little tendency for the opening torque to become abnormally high. Since opening is easy and the amount of lubricant transferred to the surface is not excessive, disadvantages such as so-called wax floating and off-flavor caused by transfer to the contents can be eliminated. In the present invention, the fact that the amount of lubricant on the liner surface is maintained within an appropriate range over a long period of time by incorporating a plasticizer-insoluble organic polymer filler into plastisol was discovered as a phenomenon. However, its theoretical elucidation has not yet been sufficiently carried out. However, the present inventors estimate the reason as follows. That is, the organic polymer filler used in the present invention has a lower specific gravity than, for example, an inorganic filler, and has excellent dispersion stability in plastisol. Therefore, the organic polymer filler is present in a dispersed state on or near the surface of the liner layer, and the organic polymer filler is also present in a uniformly dispersed state inside the liner layer. Incidentally, the migration of the lubricant to the liner surface is caused by the movement of the lubricant in the continuous phase of the soft vinyl chloride resin, but in the liner of the present invention, the organic polymer filler particles present at or near the surface are It blocks the movement of lubricant to the surface, and the organic polymer filler particles present inside act to lengthen the distance that lubricant moves to the surface, so the amount of lubricant on the surface is kept constant. This is thought to be due to its sustained release effect. (Preferred Embodiment of the Invention) Lid Structure The container lid with a liner of the present invention includes applying plastisol of vinyl chloride resin to at least the portion of the container lid shell that is to be engaged with the container mouth and gelling the plastisol. formed by In FIG. 2, which shows an example of a container lid with a liner, this lid consists of a lid shell 1 made of, for example, painted metal and a liner 2 provided inside the lid shell. The shell body 1 consists of a top plate part 3 and a skirt part 4 hanging from the periphery thereof, and lugs (claws) 5 for fastening to the container opening and opening the cap are provided at intervals at the lower end of the skirt part 4. Beads 6 are provided in areas other than the lugs. A grasping flute 7 is provided around the skirt portion 4. A liner filling groove 8 is provided around the top plate, and a liner 2 made of plastisol is formed in this groove 8. Plastisol In this specification, plastisol is a mixture of vinyl chloride resin, plasticizer, and other ingredients.
A paste that can be turned into a gel by heating to become a uniform elastic body. In the present invention, the vinyl chloride resin includes:
In addition to homopolymers of vinyl chloride, copolymers of vinyl chloride and small amounts of comonomers such as vinyl acetate, vinylidene chloride, styrene, acrylic esters, methacrylic esters, and butadiene can also be used. The average degree of polymerization of these vinyl chloride resins is
There is no particular limit, and 500 to 3000 is generally convenient. These vinyl chloride resins can be used for the purpose of the present invention, whether they are those with a relatively fine particle size obtained by emulsion polymerization method, those with relatively coarse particle size obtained by suspension polymerization method, or a mixture thereof. As the plasticizer, plasticizers commonly used for vinyl chloride resins, such as the following, can be used alone or in combination. 1 Phthalate ester Diethyl phthalate Di-n-butyl phthalate Di-i-butyl phthalate Dihexyl phthalate Di-i-heptyl phthalate Dioctyl phthalate (DOP) [n-octyl, 2-ethylhexyl, isooctyl (oxo) Di-i-heptyl-i-nonyl phthalate Di-n-octyl-n-decyl phthalate Didecyl phthalate [Includes n-decyl and i-decyl. ] Butylbenzyl phthalate Diphenyl phthalate Dicyclohexyl phthalate Dimethylcyclohexyl phthalate Dimethoxyethyl phthalate Dibutoxyethyl phthalate Ethyl phthalyl ethyl glycolate Butyl phthalyl butyl glycolate 2 Aliphatic dibasic acid ester Di-i-butyl adipate Octyl adipate [2-ethylhexyl, n-octyl] Didecyl adipate [i-decyl, n-decyl] Di(n-octyl-n-decyl) adipate Dibenzyl adipate Dibutyl sebatate [n-butyl] Sebacic acid Dioctyl [2-ethylhexyl, n-octyl] n-hexyl azelaate Dioctyl azelate [2-ethylhexyl] 3 Phosphate ester Diphenyl phosphate 2-ethylhexyl 4 Hydroxy polyhydric carboxylic acid ester Diethyl tartrate Acetyl triethyl citrate Acetyl tributyl citrate Acetyl 2-ethylhexyl citrate Monoisopropyl citrate Tributyl citrate Mono-, di-, tristeryl citrate 5 Fatty acid esters Methyl acetyl ricinoleate Ethyl palmitate Ethyl stearate n-Butyl stearate Amyl stearate Cyclohexyl stearate Butyl oleate Hydrogenated rosin methyl ester 6 Polyhydric alcohol ester Glycerin triacetate Glycerin tripropionate Glycerin tributyrate Glycerin triheptanoate Glycerin monoacetyl monostearate Glycerin monoacetyl monolaurate Triethylene glycol dicaprylate Triethylene glycol dicaprate Pentanediol diisobutyric acid ester 7 Epoxy plasticizer Epoxidized soybean oil Epoxidized castor oil Epoxidized linseed oil Epoxidized safflower oil Epoxidized linseed oil Fatty acid butyl Epoxy octyl stearate [both i-octyl and 2-ethylhexyl] 3-(2-xenoxy)-1. 2 Epoxypropane 8 Polyester plasticizer Poly(diethylene glycol, terpene maleic anhydride adduct) ester Poly(propylene glycol, adipic acid)
Ester poly(1,3-butanediol, adipic acid)
Ester poly(propylene glycol, sebacic acid)
Ester poly(1,3 butanediol, sebacic acid)
Ester poly(propylene glycol, phthalate)
Ester poly(1,3 butanediol, phthalic acid)
Ester Poly(ethylene glycol, adipic acid) ester Poly(1,6-hexanediol, adipic acid) ester Acetylated poly(butanediol, adipic acid) ester [Butanediol is of 1,3- and 1,4-type] 9 Others Alkyl sulfonic acid (C ₁₂ - C ₂₀ ) Phenol ester Alkyl sulfonic acid (C ₁₂ - _{C 20} ) Cresol ester Hydrogenated polybutene p-tert-butylphenyl salicylate Chlorinated paraffin. Suitable examples of lubricants for use in the present invention include, but are not limited to, the following: 1 Aliphatic hydrocarbon liquid paraffin Industrial white mineral oil Synthetic paraffin Petroleum wax Petrolatum Odorless light hydrocarbon 2 Silicone Organopolysiloxane 3 Fatty acid, aliphatic alcohol Higher fatty acid Fatty acid obtained from animal or vegetable oils and hydrogenated fatty acids Added products with a carbon number of 8 to 22 Hydroxystearic acid Straight chain aliphatic monohydric alcohol Products with a carbon number of 4 or more obtained by reducing animal or vegetable oils or their fatty acid esters or decomposing and distilling natural waxes Tridecyl alcohol 4 Polyglycol Polyethylene glycol Molecular weight 200-9500 Polypropylene glycol Molecular weight 1000 or more Polyoxypropylene-polyoxyethylene-block polymer Molecular weight 1900-9000 5 Amide, amine Higher fatty acid amide Oleyl palmitamide Stearyl Erucamide 2 stearomide ethyl stearate Ethylene bis fatty acid amide NN'Oleoylstearylethylenediamine NN'Bis(2hydroxyethyl)alkyl( _C12 - _C18 ) amide NN'Bis(hydroxyethyl)lauroamide N-alkyl( _C16- C ₁₈ ) Oleic acid reacted with trimethylene diamine Fatty acid diethanolamine Distearate ester of di(hydroxyethyl)diethylenetriamine monoacetate 6 Fatty acid ester of monohydric and polyhydric alcohol n-butyl stearate Hydrogenated rosin methyl ester Dibutyl sebatate <n -Butyl> Dioctyl sebatate <2-ethylhexyl, n-octyl> Glycerin fatty acid ester Glycerin lactostearyl Pentaerythritol stearate Pentaerythritol tetrastearate Sorbitan fatty acid ester Polyethylene glycol fatty acid ester Polyethylene glycol monostearate Polyethylene glycol dilaurate Polyethylene glycol monostearate Oleate Polyethylene glycol dioleate Polyethylene glycol coconut fatty acid ester Polyethylene glycol tall oil fatty acid ester Ethanediol montanate 1,3 butanediol montanate ester Diethylene glycol stearate ester Propylene glycol fatty acid ester 7 Triglycerides, waxes Hydrogenated edible fats and oils Cottonseed oil and others Edible oils Linseed oil Palm oil Glycerin ester of 12-hydroxystearic acid Hydrogenated fish oil Beef tallow Spam acetiwax Montan wax Carnauba wax Wood wax Monohydric aliphatic alcohols and aliphatic saturated acid esters <Example: Hardened Whale oil lauryl stearate, stearyl stearate > Lanolin 8 Higher fatty acid salts of alkali metals, alkaline earth metals, zinc and aluminum (metal soap) 9 Organosiloxane Polydimethylsiloxane Polymethylphenylsiloxane 10 Low molecular weight olefin resin Low molecular weight polyethylene Low molecular weight polypropylene Polyethylene oxide 11 Fluorine resin Polytetrafluoroethylene Tetrafluoroethylene/hexafluoropropylene copolymer Polychlorinated trifluoroethylene Polyvinyl fluoride 12 Others Propylene glycol alginate Dialkyl ketone Acrylic copolymer (e.g. manufactured by Monsanto) Modaflow et al.). In the present invention, among these lubricants, it is particularly desirable to use fatty acid amide or a combination of fatty acid amide and organosiloxane. Vinyl chloride resin undergoes a dehydrochlorination reaction at high temperatures, resulting in coloration and a decrease in physical properties. To prevent this, a heat stabilizer is added. As a heat stabilizer, calcium stearate,
Metal soap stabilizers such as zinc stearate and heat stabilizers for vinyl chloride resins known per se such as bisphenol A can be used. In addition to the above essential components, the plastisol composition of the present invention includes blowing agents such as azodicarbonamide, 4,4,-oxybis(benzenesulfonyl)hydrazide; calcium carbonate, finely divided silica, magnesium carbonate, talc, calcined clay, etc. fillers; pigments such as titanium white and carbon black; anionic,
A dispersant such as a nonionic, cationic or amphoteric surfactant may be blended. Prescription examples (parts by weight) of plastisol compositions used in the present invention are shown below.

[Table] According to the present invention, a plasticizer-insoluble organic polymer filler is blended into the plastisol. This organic polymer filler generally has a maximum dimension of 2 to 1500 μm,
Especially when the aspect ratio is 1 to 1000 at 5 to 50 μm,
Particularly preferred are organic fibers having a molecular weight of 5 to 750, or their powders, flakes, and flat fine particles. For example, fibers include natural fibers such as cotton, pulp fiber, cabbage, flax, hemp, ramie, juute, manila hemp, sisal hemp, and coconut fiber; recycled fibers such as rayon, polynosik, and kyupra; acetate, acetate acetate, ethyl cellulose, etc. semi-synthetic fibers; polyamide fibers such as nylon 6, nylon 66, MXD-6, nylon 4, nylon 610, and nylon 11; polyacrylonitrile fibers, polyester fibers, polyethylene fibers, polypropylene fibers, polyfluoroethylene fibers, Synthetic fibers such as polyurea fibers, polystyrene fibers, polyester ether fibers, polyvinyl alcohol fibers, and polyvinyl alcohol-polyvinyl chloride mixed spun fibers can be used. Further, flat fine particles, flakes, etc. made of these polymers can be used. Such flat fine particles can be obtained, for example, by crushing a film. Among these particles, cellulose fibers are particularly useful fillers for the purposes of the present invention because they are inexpensive and remain in their original state without melting during gelation of the plastisol. Ethylene polymer particles such as polyethylene and ethylene-acrylic acid copolymers are also readily available organic polymer fillers, which are also particularly suitable for the purposes of the present invention. In the present invention, the organic polymer filler is contained in an amount of 2 to 60% by volume, particularly 5 to 40% by volume, based on the vinyl chloride resin.
It is added to plastisol in an amount equal to volume %, but by adding an organic polymer filler to plastisol, even when a relatively large amount of lubricant is contained in plastisol, the lubricant can be effectively transferred to the contents. The advantage is achieved that it can be suppressed. Manufacture of Lid Plastisol is applied to the area where a seal between the lid and the container opening is required by rotating the container lid shell and injecting it into the shell with a nozzle. Of course, if necessary, the plastisol may be pressed into a predetermined liner shape using a heated mold. The plastisol applied to the container lid shell is then heated to gel and, if necessary, foam to form an unfoamed or foamed liner. When using a foam liner, its apparent specific gravity is
A range of 0.4 to 1.2 is desirable. The container lid shell can be easily manufactured by subjecting the coated metal material to per se known means, such as stamping press molding and scoring. As the metal material forming the container lid shell, light metals such as sheet-like or foil-like surface-untreated steel (black plate), surface-treated steel, aluminum, etc. are used. Surface-treated steel includes chemical treatments such as phosphoric acid treatment and chromic acid treatment on a steel substrate; chemical conversion treatments such as electrolytic chromic acid treatment; electrolytic plating treatments such as electrolytic tin plating, electrolytic zinc plating, and electrolytic chrome plating; and molten aluminum plating. Examples include those that have been subjected to a hot-melt plating process such as a hot-dip tin plating process. At least the surface of these metal materials that will become the inner surface of the lid is painted with a protective paint. Suitable examples of paints include thermosetting resin paints, such as phenol-formaldehyde resins, furan-formaldehyde resins, xylene-formaldehyde resins, ketone-formaldehyde resins, urea-formaldehyde resins, melamine-formaldehyde resins, alkyd resins,
Unsaturated polyester resin, epoxy resin, bismaleimide resin, triallyl cyanurate resin, thermosetting acrylic resin, silicone resin, oil-based resin, or thermoplastic resin coating, such as vinyl chloride-vinyl acetate copolymer, vinyl chloride-acetic acid These include partially saponified vinyl copolymers, vinyl chloride-maleic acid copolymers, vinyl chloride-maleic acid-vinyl acetate copolymers, acrylic polymers, saturated polyester resins, and the like. These protective coatings may be used alone or in combination of two or more. It is preferable that these paints have thermal adhesion to the soft resin constituting the liner, and if the liner constituting resin is made of vinyl chloride resin, the vinyl chloride resin content or acrylic resin content may be reduced. Particularly preferred are paints containing The amount of plastisol applied varies depending on whether it is foamed or unfoamed, the shape of the liner, etc., but it is generally best to apply it to the sealing part in a thickness of 0.3 to 4 mm. Gelation of plastisol is
Heating is preferably carried out at a temperature of 160 to 280°C for 10 seconds to 3 minutes. (Effects of the Invention) When a liner is formed using the plastisol of the present invention, a feature is obtained in that the amount of lubricant on the liner surface remains almost constant regardless of the passage of time. Therefore, with the liner of the present invention, excellent capping properties can be obtained in the initial stage, making it possible to cap with sufficiently high sealing pressure, and even after sealing over time.
It is easy to open the cap as there is no tendency for the opening torque to become abnormally high, and since the amount of lubricant transferred to the surface is not excessive, it eliminates disadvantages such as so-called wax floating and off-flavor caused by transfer to the contents. will be done. (Example) Plastisol manufacturing method of Examples and Comparative Examples Measure the plasticizer into a mixing tank and add the vinyl chloride resin lubricant filler or cellulose based on the volume parts of Examples and Comparative Examples, and add the blowing agent for Example 4. Add while mixing with a stirrer, stir for 30 minutes, then transfer to a defoaming tank while filtering, and maintain a vacuum of 0 cmHg.
The mixture was stirred under reduced pressure for 90 minutes to remove bubbles from the sol to obtain plastisol. Epoxyphenol paint was used as an undercoat on a tin plate with a thickness of 0.17m/m, and vinylphenol paint was applied as an adhesive paint to the liner material.
A cap with a diameter of 63 m/m was prepared by sequentially baking and drying each cap for 10 minutes at a temperature ranging from .degree. Comparative Examples 1 and 2 and Example 1,
Heat each of the plastisols 2, 3, and 4 to 40℃, and apply the liner thickness to the inside of the cap from the nozzle.
The caps were coated to a thickness of 1.0 m/m and baked at 240°C for 50 seconds to prepare caps for Examples and Comparative Examples of the present invention, and the following tests were conducted. The test cap was stored in a constant temperature and humidity machine for 2 hours at a humidity of 48% and a temperature of 15°C for 12 hours, followed by a cycle of 12 hours at 20°C. After being stored for 2 weeks at a humidity of 70% and a temperature of 25°C for 12 hours, followed by a cycle of 12 hours at 32°C, it was immediately subjected to capping property and opening torque tests. A glass bottle for this cap was filled with hot water at 85°C to heat the test cap, soften the liner, cap it, and cool it with water. Bring this to room temperature 1
The bottle was stored for several months, and the opening torque and the amount of biting into the liner at the mouth of the bottle were measured. Regarding the opening torque, please refer to 2.
Measurements were also made after 3 months and after 3 months. Separately, the humidity is 48% and the temperature is 15℃ for 12 hours, followed by 20℃ for 12 hours.
A cap that has been stored for two weeks in a time cycle is 85
A bottle filled with hot water at a temperature of 0.degree.

【table】

【table】 [Brief explanation of drawings]

FIG. 1 is a diagram showing the relationship between time and surface lubricant amount in a migration acceleration test for liners formed from plastisol used in Examples, and FIG. 2 is a diagram showing an example of a container lid with a liner of the present invention. FIG. 1 is a container lid shell, and 2 is a liner.

Claims (1)

[Scope of Claims] 1. A composition in which a plastisol containing a vinyl chloride resin, a plasticizer, a lubricant, and a stabilizer is blended with a plasticizer-insoluble organic polymer filler in an amount of 2 to 60% by volume per vinyl chloride resin. A container lid with a liner, characterized in that it has a liner formed from. 2 The organic polymer filler has a maximum dimension of 2 to 1500μ
2. The container lid with a liner according to claim 1, wherein the particles have an aspect ratio of 1 to 1,000. 3. The container lid with liner according to claim 1, wherein the organic polymer filler is cellulose fiber powder. 4. A container lid with a liner according to claim 1, wherein the organic polymer filler is an ethylene polymer powder. 5. Claim 1, wherein the plasticizer is 45 to 160% by weight and the lubricant is 1.5 to 10% by weight based on the vinyl chloride resin.
Container lid with liner as described.