JP3186156B2 - Glass containers for sealed packaging - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a glass container for hermetically sealed packaging, and more particularly to a glass container capable of heat-sealing a lid and having a heat-resistant and water-resistant sealed portion, and having a sterilized boil. And a glass container for hermetically sealed packaging that can be sterilized by retort.

[0002]

2. Description of the Related Art It has long been attempted to apply a lid to the open end of a glass container by heat sealing, but since the adhesive force between the glass and the heat sealing resin is insufficient, Various attempts to improve this have been proposed.

[0003] Japanese Patent Publication No. 61-9181 discloses a sealed package in which a silane coupling agent is applied to the open end face of a glass container having a metal oxide coating layer, if necessary, and then a thermoplastic resin is formed. A glass container is described (existing technology 1).

Japanese Patent Publication No. 3-2754 discloses that a resin layer A is formed by a combination of a glass container having a resin layer A on an opening end face and a lid member having a resin layer B formed on one side of a base such as aluminum foil. And (a) either an ionomer or a mixture thereof with another resin, or (b) a polyethylene or a mixture thereof with another resin, and a material for a hermetically sealed package which is the other where the resin layer B remains. (Existing technology 2).

Japanese Patent Publication No. 3-6067 discloses that a resin layer A is formed by a combination of a glass container having a resin layer A on an open end face and a lid member having a resin layer B formed on one side of a base such as aluminum foil. It describes an acid-modified polypropylene alone or a mixture thereof with another resin, and a material for a sealed package in which the resin layer B is polypropylene, an acid-modified polypropylene or a mixture thereof with another resin (existing technology 3).

JP-A-58-125641 discloses that a contaminant is removed from an open end face of a glass container, a tin oxide or titanium oxide film is formed on the surface, and then a chromium (III) organometallic complex is formed. Describes a method for treating a glass container for opening sealing, which comprises treating with an existing method (existing technology 4).

[0007]

According to these treatment means, the adhesion to the heat-sealing resin is certainly enhanced as compared with the untreated one, but the time-lapse in the presence of moisture is Adhesion deterioration is remarkable, especially when passing through a sterilization treatment such as retort sterilization.

[0008] For example, in the glass / metal oxide layer / acid-modified polypropylene layer structure recognized in the existing technologies 1 and 3, the adhesive deterioration due to moisture is remarkable, and the applicable contents are actually limited to powder. There is a limitation, and there is a problem that the storage stability is reduced under a high-temperature and high-humidity condition.

Further, in the glass / metal oxide layer / silane coupling agent / ionomer layer configuration found in the existing technologies 1 and 3, even if the water resistance is slightly improved as compared with the above-mentioned known examples, the application is not restricted. The sterilization conditions that can be achieved are at most up to boil sterilization and are not yet sufficiently satisfactory in terms of the preservability of the contents.

Further, even in the glass / metal oxide layer / acid-modified polypropylene-dispersed epoxy phenol resin coating film of the existing technology 3, the adhesive deterioration due to the retort sterilization is remarkable,
Almost no adhesion is maintained.

[0011] Furthermore, the glass /
In the combination of the container of the metal oxide layer / chromium fumarate complex layer and the lid having the ionomer / substrate layer structure, there is also a limitation in application that the hot pack is the limit.

As described above, in the conventional heat-sealed glass container, a sealed package that can withstand retort sterilization cannot be obtained because the glass surface is extremely hydrophilic and the glass or glass surface-treated layer and the pre-coated resin layer are combined with each other. This is considered to be due to delamination occurring between them, and the adhesive strength was not increased to the cohesive failure strength of the resin layer.

Accordingly, an object of the present invention is to provide a heat-sealed part which is remarkably excellent in water resistance, heat resistance and hot water resistance while being sealed by heat sealing, and has an adhesive strength even after retort sterilization which causes cohesive failure of a resin. It is an object of the present invention to provide a hermetically sealed glass container having an increased strength.

[0014]

According to the present invention, an organic metal complex layer and a thermosetting resin coating film in which an acid-modified olefin resin is dispersed are provided in this order in a sealing opening of a glass container. A heat-sealable hermetically sealed glass container characterized by being formed is provided.

In the present invention, it is desirable that the glass substrate of the sealing opening has a thin layer of tin oxide and / or titanium oxide on the surface, and the organometallic complex is a compound containing a carboxyl group and titanium, zirconium or chromium. And a complex with

The thermosetting resin coating film is composed of an acid-modified olefin resin and a thermosetting resin at 99.2: 0.8 to 5
It is preferred that the coating be composed of a coating containing 0:50 by weight.

According to the present invention, there is further provided a container body in which an organometallic complex layer and a thermosetting resin coating in which an acid-modified olefin resin is dispersed are formed in this order in a sealing opening of a glass container. And a lid having a heat-seal layer of an olefin-based resin provided on a substrate and heat-sealed in a state where the coating film and the heat-seal layer face each other. Is done.

[0018]

According to the present invention, an organometallic complex layer and a thermosetting resin coating in which an acid-modified olefin resin is dispersed are provided in this order and adjacent to each other in a sealing opening of a glass container. This is a remarkable feature, and a novel effect is that the heat seal strength after retort sterilization is increased not only at the interface but also at the cohesive failure strength of the heat sealable resin.

Conventionally, both the use of an organometallic complex layer and the use of a thermosetting resin coating in which an acid-modified olefin-based resin is dispersed in a hermetically sealed glass container capable of being heat-sealed belong to the known art. However, as far as the present inventors know, it is still unknown that an organometallic complex layer and a thermosetting resin coating film in which an acid-modified olefin resin is dispersed are provided in this order and in an adjacent relationship in the sealing opening. Not been. Moreover, the heat seal strength after retort sterilization is not interfacial peeling, but it is possible to increase the cohesive failure strength of the heat sealable resin only with the above-described sequence and combination of lamination structures, and in other combinations. Have difficulty.

This fact will be clear by referring to the following examples and comparative examples. That is, even if an organic metal complex layer is used, if the resin layer applied thereon is an ionomer resin, the temperature of the resin becomes higher than the melting point of the resin during retort sterilization, so that interfacial peeling occurs, resulting in poor sealing. On the other hand, when a thermosetting resin coating film in which an acid-modified olefin resin is dispersed is used as a primer for adhesion, if the base layer is only a metal oxide layer, a sealing failure occurs during retort sterilization, and a metal oxide layer is formed. Even if a silane-based coupling agent is applied on the material layer, it is possible to prevent poor sealing at the time of retort sterilization. However, when the opening is performed, interface separation between the glass and the coating film occurs, and the heat sealing strength is 1. 0.5 kg / 1
It is only on the order of 5mm width. On the other hand, in the combination of the organometallic complex layer and the thermosetting resin coating film in which the acid-modified olefin resin is dispersed, when the opening is performed after the retort sterilization, the cohesive failure of the heat sealing resin is caused instead of the interfacial peeling. As a result, the opening can be performed, and the heat sealing strength can be increased to the order of 2.8 kg / 15 mm width.

In the present invention, the heat sealing strength is increased even to the cohesive failure strength of the heat sealing resin, although the glass surface is extremely hydrophilic.
The key is the combination of an organometallic complex layer and a thermosetting resin coating in which an acid-modified olefin resin is dispersed. The organometallic complex layer has strong adhesion to a glass substrate or a surface-treated glass substrate. On the other hand, it is considered that a chemically strong bond is also exhibited with a thermosetting resin coating film in which an acid-modified olefin resin is dispersed.

[0022]

BEST MODE FOR CARRYING OUT THE INVENTION

(Glass Container Substrate) In the present invention, as the glass container, in addition to the most common soda-lime glass container, those having various glass compositions such as lead glass and borosilicate glass known under the name of Pyrex are used. Applied. Examples of the container form include an arbitrary container having a sealing opening, for example, a narrow or wide-mouthed glass bottle, a glass cup, a glass tray or a dish, and the like. These glass containers are superior to plastic containers and the like in that gas permeation through the vessel wall is substantially zero, and have no corrosiveness when the contents are filled. It is also excellent for metal containers.

While the glass container has the above-mentioned advantages, it tends to be inferior in molding accuracy of the mouth, which is most important in terms of sealing, as compared with other containers. For this reason, conventionally, as a highly reliable sealing method, stoppering is mainly performed with various caps, but in this case, a rigid cap shell and an elastic gasket or liner are required, and the sealing is performed. However, there is still room for improvement in that it requires a large amount of resources, has a problem of disposal after use, and requires special equipment and mechanisms for opening.

In this sense, it is expected that providing a heat-sealing lid at the sealing opening of the glass container will bring many advantages. However, since the surface of the glass is very hydrophilic, it can withstand retort sterilization. It has already been pointed out that hot water-sealed heat seal bonds cannot be formed.

(Organic Metal Complex Treatment) According to the present invention, the sealing opening of the glass container is surface-treated with an organometallic complex.
As the organometallic complex, all the organometallic complexes conventionally used for surface treatment of this kind of glass and aluminum are used, but as the one particularly suitable for the purpose of the present invention, a carboxyl group-containing compound is used. , Titanium, zirconium or complexes with chromium.

The carboxyl group-containing compound may be any compound having the ability to form a complex with the above-mentioned metals. For example, carboxylic acids and oxycarboxylic acids are used, and in particular, ethylenically unsaturated carboxylic acids or oligomers or polymers thereof, and tannic acid Etc. are used.

Examples of the organometallic complex particularly suitable for the purpose of the present invention include chromium (III) fumarate, zirconium polyacrylate, titanium tannate and the like.

The above-mentioned organometallic complex is generally applied by applying an aqueous treating agent as a precursor to a sealing opening of a glass container,
It is applied by drying. As a coating method, for example, dip coating, roller coating, spray coating, electrostatic coating, or the like is used. As a drying method, a method of drying with an oven, a heater, or the like after coating, a method of preheating the mouth of a glass container with a burner or the like before coating, and drying with heat storage are used. In addition, the coating amount is determined from the concentration of the aqueous treating agent and the coating amount. In addition, by preparing a calibration curve in advance, it can be obtained from the intensity of fluorescent X-rays or the like. The amount of coating varies depending on the organometallic complex to be applied, but generally ranges from 0.1 to 3
2,000 mg / m ² , especially 1 to 2000 mg / m ² is suitable.

Prior to applying the organometallic complex to the sealing opening of the glass container, tin oxide and / or tin oxide is applied to the surface of the sealing opening.
Alternatively, it is preferable to form a thin layer of titanium oxide in order to improve the wettability when applying the organometallic complex and enhance the adhesion of the organometallic complex to glass. The formation of a thin layer of tin oxide and / or titanium oxide is a so-called hot-end treatment in which the sealing opening is treated with a gas such as tin chloride or titanium chloride while the glass container is still being formed. Can be performed. Of course, following this hot end treatment, the organometallic complex can be applied while the glass is hot.

According to the present invention, a thermosetting resin coating layer in which an acid-modified olefin resin is dispersed is provided on the organometallic complex layer. This paint is composed of a continuous phase of a thermosetting resin solution capable of forming a coating film and a dispersed phase of acid-modified olefin resin particles dispersed in the continuous phase. The modified olefin-based resin is preferentially distributed on the surface while maintaining the above-mentioned dispersion state, and contributes to the enhancement of thermal adhesion with a heat seal resin such as the olefin-based resin. The acid-modified olefin resin has a strong bond at the interface with the thermosetting resin due to the presence of the carboxyl group. Then, a strong bond is formed in the organometallic complex layer. This is the reason why strong heat sealing strength can be obtained between the glass and the heat sealing material.

According to the feature of the present invention that a bond is formed in the order of glass, an organometallic complex, a thermosetting resin, and an acid-modified olefin-based resin in the present invention, the organometallic complex layer and the olefin-based resin It should be understood that another thermosetting resin coating layer may be formed between the heat-setting resin coating layer and the thermosetting resin coating layer.

As the acid-modified olefin-based resin, a carbonyl group derived from an acid or an acid anhydride described below is used in an amount of 0.1 to 0.1%.
An olefin resin containing a polymer of 01 to 600 meq / 100 g, particularly 1.0 to 200 meq / 100 g, is used.

In the present invention, the acid-modified olefin resin may be a known acid or acid anhydride-containing ethylenically unsaturated monomer, such as a graft copolymer, a block copolymer, a random copolymer or a terminal treatment. Among those introduced into the main chain or side chain of the olefin resin, those satisfying the above conditions are used.

Suitable examples of the ethylenically unsaturated monomer having a carboxylic acid or a carboxylic anhydride are as follows. Ethylenically unsaturated carboxylic acids: acrylic acid, methacrylic acid, maleic acid, fumaric acid, crotonic acid, itaconic acid,
Citraconic acid, 5-norbornene-2,3-dicarboxylic acid. Ethylenically unsaturated carboxylic anhydrides: maleic anhydride, citraconic anhydride, 5-norbornene-2,3-dicarboxylic anhydride, and tetrahydrophthalic anhydride.

As the olefin, ethylene, propylene, butene-1, pentene-1,4-methylpentene-
One or more combinations such as one. When the acid-modified olefin-based resin is a graft polymer, as the trunk polymer, low-, medium- or high-density polyethylene, polypropylene, ethylene-propylene copolymer,
Polybutene-1, polypentene-1, ethylene-butene-1 copolymer, ethylene-propylene-butene-1 copolymer and the like are used.

The acid-modified olefin resin has a molecular weight sufficient to form a film, generally a number average molecular weight (Mn) of 1
It is desirable to have a molecular weight of 10,000 to 1,000,000, especially 20,000 to 500,000.

The particle size of the acid-modified olefin resin is as follows:
The volume-based median diameter is 0.3 to 50 μm, especially 1.
It is desirable that it is in the range of 0 to 20 μm from the viewpoint of dispersibility and adhesion in the paint. The particles of the acid-modified olefin resin preferably have a monodispersion or a particle size distribution close thereto, and the standard deviation (σ) of the particle size is particularly preferably within 1/3 of the average particle size. Such particles are obtained by dissolving an acid-modified olefin-based resin in an aromatic solvent such as xylene during heating and cooling the solution or adding a negative solvent such as an aliphatic hydrocarbon or a derivative thereof to the solution. And an acid-modified olefin resin.

As the thermosetting resin capable of forming a coating film (hereinafter, also referred to as a base resin), any thermosetting resin having a capability of forming a coating film may be used. It is desirable to use a material having a large density of 0.1 g / cc or more from the viewpoint of improving the adhesiveness. Further, the concentration of the functional groups such as hydroxyl groups and carbonyl groups in the base resin was adjusted to 1 meq /
By setting it to g or more, it becomes possible to further enhance the adhesion of the primer layer to the glass substrate.

In the present invention, in the base resin for forming a coating film, the hydroxyl group may be contained in the main chain or side chain of the polymer in the form of an alcoholic hydroxyl group or a phenolic hydroxyl group or a combination thereof. The carbonyl group may be contained in the main chain or side chain of the polymer in the form of carboxylic acid, carboxylate, carboxylate, carboxylic amide, ketone, imide, urea or urethane.

The base resin to be used may be a thermosetting resin vehicle widely used in the field of coating, as long as it satisfies the above-mentioned requirements. For example, a phenol-formaldehyde resin, a urea-formaldehyde resin, a melamine A thermosetting resin composed of one or a combination of two or more of formaldehyde resin, xylene / formaldehyde resin, epoxy resin, alkyd resin, thermosetting polyester resin, thermosetting acrylic resin, and urethane resin is used. These are acrylic resins, vinyl chloride-vinyl acetate copolymers, vinyl chloride-vinyl acetate-maleic acid copolymers, vinyl resins such as vinyl butyral resins, styrene-butadiene-acrylic acid as long as the thermosetting properties are not impaired. It may be modified with a thermoplastic resin component such as an ester copolymer or a polyamide resin.

Base resins for forming a coating film suitable for the purpose of the present invention include phenol resin-epoxy resin paint, urea resin-epoxy resin paint, melamine resin-epoxy resin paint, phenol resin-epoxy resin-vinyl resin paint and the like. It is.

The mixing ratio between the film-forming resin (A) and the acid-modified olefin-based resin (B) is determined from the viewpoints of coatability, adhesiveness and heat sealability of the obtained coating film.
When the acid-modified olefin-based resin (B) increases by a certain amount or more,
From the viewpoint of coatability, the coating film may be cracked during baking, and the formed coating film may have irregularities. Also,
In some cases, the desired adhesion between the organometallic complex and the coating film cannot be obtained. Conversely, if the amount is less than a certain value, the desired heat sealability may not be obtained. Although these phenomena vary depending on the resin used, etc., the film-forming resin (A) and the acid-modified olefin-based resin (B) are generally 99.2: 0.8 to 50:50, particularly 99: 1 to 50:50. It is preferably present in a weight ratio of 80:20.

In the present invention, the organic solvent of the paint includes
Ketones such as acetone, methyl ethyl ketone, methyl isobutyl ketone, cyclohexanone and isophorone; alcohols such as diacetone alcohol, n-butanol, methyl cellosolve and butyl cellosolve; aromatic hydrocarbons such as toluene, xylene and decalin alone or 2
Used in combinations of more than one species.

The solid content concentration in the paint varies depending on the coating method, but is generally 5 to 50% by weight, particularly 15 to 4% by weight.
A range of 0% by weight is suitable.

The coating composition of the present invention may contain, in addition to the above essential components, other compounding ingredients known per se, such as heat stabilizers, antioxidants, pigments, fillers, leveling agents, lubricants,
Of course, a plasticizer and the like can be blended at a known blending ratio.

In order to form a primer layer on the surface of the glass substrate, the above-mentioned liquid coating composition is applied to this surface. For applying the primer to the glass substrate, any known coating means can be used, for example, dip coating, spray coating, roll coater, bar coater, electrostatic coating, electrodeposition coating, or the like.

The coating amount of the primer layer on the surface of the glass substrate, that is, the weight of the resin non-volatile content per unit surface area of the substrate is generally in the range of 10 to 500 mg / dm ² , particularly 30 to 100 mg / dm ^2. Is preferable in order to achieve a desirable combination of retort resistance and adhesiveness. Among these, the coating amount of the acid-modified olefin resin (A) is 0.01 to 100 mg / dm ² , especially 0.1.
To 10 mg / dm ² , and the coating amount of the base resin (B) is 1
To 500 mg / dm ² , especially 10 to 100 mg / d
m ² .

The coated glass substrate is baked to obtain a dried or cured coating film in which the acid-modified olefin resin is distributed in the upper layer. As the baking temperature, a temperature of 180 to 300 ° C. can be used.

The glass container of the present invention is used for heat sealing with various peel lids or caps.
Even if these lids have flexibility like peel lids,
Alternatively, a material having rigidity like a cap may be used, but in any case, an inner surface material made of a heat seal resin is provided.

In the present invention, the resin used for the heat sealing material is preferably an olefin resin, for example, low density, medium density or high density polyethylene, isotactic polypropylene, ethylene-
Polyolefins such as butene-1 copolymer, polybutene-1, ethylene-hexene copolymer, ethylene-propylene copolymer, ethylene-propylene-non-conjugated diene terpolymer, or ethylene-based olefins other than olefins An olefin copolymer or an acid-modified polyolefin containing a small amount of unsaturated monomer can be used. Such olefin copolymers or acid-modified polyolefins include ethylene-vinyl acetate copolymer (EVA), saponified ethylene-vinyl acetate copolymer (EVAL), ethylene-acrylic acid copolymer, ethylene-methyl methacrylate Copolymers, unsaturated carboxylic acid-modified polyethylene (for example, maleic acid, acrylic acid, methacrylic acid and esters thereof as unsaturated carboxylic acids), unsaturated carboxylic acid-modified polypropylene (unsaturated carboxylic acid is maleic Acid, acrylic acid and esters thereof), ionomers, chlorosulfonated polyethylene and the like.

These olefin-based resins can be used alone or in combination of two or more. In addition, ethylene-propylene rubber (EPR), ethylene-propylene-diene rubber (E
PDM), polyisobutylene (PIB), butyl rubber (IIR), polybutadiene (PE), natural rubber (N
R), stereospecific polyisoprene, nitrile rubber (NB
R), an elastomer such as a styrene-butadiene copolymer or a block copolymer, a styrene-isoprene copolymer or a block copolymer, and polychloroprene (CR).
The seed or two or more can be incorporated, for example, in an amount of 1 to 60% by weight to improve the required elastic properties of the packing or sealant.

In the present invention, the cohesive force of the heat seal resin layer is somewhat reduced by blending a plurality of different types of olefin resins, whereby an easily peelable heat seal can be formed. Such a resin composition for heat-peeling easily peelable includes 95: 5 to 5: 9 of a copolymer mainly composed of polyethylene or ethylene and a copolymer mainly composed of polypropylene or propylene.
5, especially compositions in a weight ratio of 90:10 to 10:90.

These polyolefins may be added to phenol-based, organic sulfur-based, organic nitrogen-based, or organic phosphorus-based antioxidants or heat stabilizers, metal soaps or other fatty acid derivatives in accordance with a formulation known per se. , A filler such as calcium carbonate, white carbon, titanium white, magnesium carbonate, magnesium silicate, carbon black, and various clays, or a compounding agent such as another coloring agent.

The lid may be a monomer composed of only these olefinic resins, but these are used as the inner surface layer, and one or several layers of any known container forming material are laminated on the substrate side. It may be something. As the substrate, for example, a transparent barrier film made of polyvinylidene chloride resin, ethylene-vinyl alcohol copolymer, nylon resin, or the like, or a vapor-deposited film or a metal foil is suitably used.

The lid is preferably made of a metal substrate in that heat sealing can be performed by high-frequency induction heating and has excellent gas barrier properties. Examples of the metal substrate include steel, aluminum, and alloys thereof. These metal substrates may be made of steel plated with zinc, tin, chromium, aluminum, or the like, or steel treated with phosphoric acid, chromic acid, or electrolytic chromic acid. . The shape of the metal substrate is
It consists of a metal foil for a peel lid or a rolled sheet in the case of a crown shell, cap or other container lid.

These metal substrates are previously coated with an epoxy-amino resin such as a phenol-epoxy resin, an epoxy-urea, or a phenol- Known primers such as epoxy-vinyl and epoxy-vinyl can be applied in advance, and the same type of primer used for the treatment of the glass substrate may be used for bonding the olefin resin to the metal.

Sealing by heat sealing is performed at a temperature at least 10 ° C. higher than the higher melting point of the above-mentioned acid-modified olefin resin and the melting point of the olefin resin, generally 120 to 300 ° C., particularly 150 to 300 ° C. 23
At a temperature of 0 ° C., it is thermally bonded to the olefin resin of the lid via the primer layer on the glass container. The heat seal is a heated heat seal bar, high frequency induction heating,
Irradiation, ultrasonic irradiation, plasma, laser or the like can be used.

[0058]

EXAMPLE A wide-mouth bottle was prepared as a glass container. Further, a wide-mouth bottle having a tin oxide film formed on the surface by hot end treatment was also prepared. As a treating agent applied to the surface of the mouth of the glass container, Volan (treatment agent 1) manufactured by Du Pont, which forms a chromium (III) fumarate-based organometallic complex, and a zirconium polyacrylate-based organic metal Surfcoat 147/148 (manufacturing agent 2) manufactured by Nippon Paint Co., Ltd., which forms a complex, and Palcoat 3751 (processing agent 3) manufactured by Nippon Parkerizing Co., Ltd., forming a titanium tannate-based organometallic complex were prepared. For comparison, γ-aminopropylethoxysilane and γ were used as silane coupling agents.
-1% of methacryloxypropyltrimethoxysilane
Aqueous solutions (treatment agents 4 and 5) were also prepared. Table 1 summarizes each treatment agent and formed film.

[0059]

[Table 1]

As a paint to be applied to the mouth side of the glass container, a modified polypropylene having a maleic acid modification rate of 1% was coated at 10 PHR.
A dispersed epoxy-phenol-based paint (paint 1), a modified polypropylene paint (paint 2) having a maleic acid modification rate of 2%, and an ionomer emulsion (paint 3) were prepared. Table 2 summarizes each paint and formed coating film.

[0061]

[Table 2]

As a cover material, a 12 μm biaxially stretched polyethylene terephthalate film, a 15 μm biaxially stretched nylon film, a 20 μm aluminum foil, a 45 μm polypropylene layer, a 5 μm propylene-ethylene random copolymer, and a linear low density polyethylene. A peelable lid for a retort was prepared by laminating two layers of a coextruded film composed of a blend layer in this order. Also, 5
A lid in which an ionomer resin was extrusion-coated to a thickness of 50 μm on one side of a 0 μm aluminum foil was prepared.

The opening of the prepared glass container was heated to about 150 ° C. with a gas burner, each treating agent was applied by a roll coater, and the container was dried by storing heat. Next, each paint was similarly applied by a roll coater and baked in an oven at 180 ° C. or 220 ° C. for 5 minutes. In addition, the thickness of the coating film was about 20 μm to 30 μm. The container thus prepared was filled with 70 ° C. hot water slightly less than the full-pour volume as a content, and heat-sealed by high-frequency induction heating using the lids described above. Thereafter, these filled and sealed containers were subjected to a retort treatment at 120 ° C. for 30 minutes. In this way, filled and sealed containers of various combinations shown in Table 3 were prepared.

[0064]

[Table 3]

With respect to these filled and sealed containers, the presence or absence of sealing failure due to the retort treatment, the heat sealing strength, and the peeling state were examined. The results are shown in Table 4.

[0066]

[Table 4]

In Examples 1, 2, 3, and 4, the seal strength was 2.7 kg / 15 mm width to 2.8 kg / 15 m on average.
m width, and the minimum value was 2.3 kg / 15 mm width. This evaluation result satisfies the regulated value of 2.3 kg / 15 mm width applied to plastic containers for retort foods in Notification No. 20 of the Ministry of Health and Welfare. Also,
In Examples 1, 2 and 3, the peeling also resulted in the cohesive failure of the inner surface material of the lid, and the adhesive strength between the glass and the coating film seems to be sufficiently high. In Example 4, interfacial peeling between the glass and the coating film was partially observed.

In Comparative Examples 2, 3, and 6, the average seal strength was 1.5 kg / 15 mm width and 0.7 kg / 1, respectively.
The width was 5 mm and the weight was 0.5 kg / 15 mm. Also, almost the entire surface was peeled off at the interface between the glass and the coating film.

In Comparative Examples 1, 4, and 5, all of the samples showed poor sealing due to the retort treatment. Insufficient sealing is due to interface peeling between the glass and the coating film or between the glass and the lid material.

As in Examples 1, 2, 3, and 4, the container in which the organometallic complex layer and the acid-modified polypropylene resin-dispersed thermosetting coating film were formed in this order in the sealing opening of the glass container was as follows: Maintained high sealing strength and exhibited excellent retort resistance. In addition, these containers are at 37 ° C and 80% relative humidity.
No decrease in seal strength was observed in a three-month aging test under high temperature and high humidity.

[0071]

According to the present invention, an organometallic complex layer and a thermosetting resin coating film in which an acid-modified olefin resin is dispersed are formed in this order in a sealing opening of a glass container. With, while being sealed by heat seal,
The heat-sealed portion was remarkably excellent in water resistance, heat resistance and hot water resistance, and a glass container for hermetic packaging in which the adhesive strength was increased to the cohesive failure strength of the resin even after retort sterilization could be provided.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a heat seal portion illustrating a glass container according to the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 ... Glass container main body 2 ... Lid 3 ... Organometallic complex layer 4 ... Acid-modified olefin resin dispersion thermosetting resin coating film layer 5 ... Heat sealing resin layer 6 ... Lid base

──────────────────────────────────────────────────続 き Continued on the front page (58) Field surveyed (Int. Cl. ⁷ , DB name) B65D 53/00 B65B 7/28 B65D 77/20

Claims (5)

(57) [Claims] 1. A heat seal, wherein an organic metal complex layer and a thermosetting resin coating in which an acid-modified olefin resin is dispersed are formed in this order in a sealing opening of a glass container. Possible glass containers for hermetic packaging. 2. The glass container according to claim 1, wherein the glass substrate of the sealing opening has a thin layer of tin oxide and / or titanium oxide on the surface. 3. The glass container according to claim 1, wherein the organometallic complex comprises a complex of a carboxyl group-containing compound and titanium, zirconium or chromium. 4. The glass container according to claim 1, wherein the coating film is made of a paint containing an acid-modified olefin resin and a thermosetting resin in a weight ratio of 99.2: 0.8 to 50:50. 5. A container body in which an organometallic complex layer and a thermosetting resin coating film in which an acid-modified olefin resin is dispersed are formed in this order in a sealing opening of a glass container, A heat-sealing sealed packaging glass container, wherein a lid provided with an olefin-based resin heat-sealing layer is heat-sealed with the coating film and the heat-sealing layer facing each other.