JPS59103805A - Method of sealing glass vessel by thin closure - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method of sealing a non-porous, thin, flexible type of closure to the finis lip of a glass container, typically a jar type container. . Typically such methods involve providing a non-porous, thin, flexible claw, typically an aluminum metal foil, where the aluminum metal foil is heat-sealable to the backside thereof. Coated with thermoplastic resin,
The closure is adapted to securely engage the upper termination layer of the glass container. In typical practice, the glass is coated with a heat-sealable adhesive composition suitable to provide an interface between a non-porous, thin, flexible claw coated with a thermoplastic resin and the glass surface of the container. Coat the upper terminal lip of the container.

Much research has been done on dry foods and cold-filled foods such as dried soups and frozen dairy products. For example, in UK patent application no. 2030703, published on 02/02/2030, a metal foil applied to the rim and opening of a glass container is exposed to heat and pressure to create a bond between the glass container and the metal foil. Discloses a metal foil that is secured to the rim with a heat-activated adhesive by adding a silicone material, which does not spread or harm the bond of the adhesive even if the container contains water-containing contents. Glass-compatible bonding promoters, such as organic compounds such as silanes, are applied to the rim of the container or incorporated into the adhesive.

This method is not intended for hot filling use.

15#, Japanese Patent No. J t 077-lI-≠7 for containers with lids that can be opened easily and dated 2 years j month/≠ [Tokyo 5eikan Kaish
a)) can be used, for example, by hot-bonding (hot-b
Discloses a container formed by wrapping a sheet or film made of a laminate made of a sheet of plastic or a sheet of plastic, such as a plastic sheet or metal foil, and a sheet of plastic. Thermal adhesive plastic materials laminated to metal foils can be made from modified olefin resins such as acid-modified polyolefins, ionomers, ethylene-vinyl acetate copolymers, copolymers of ethylene-unsaturated acids (or their esters), blends thereof or polyamides. selected from. A small diameter opening in the film or sheet can be easily opened by bending the heat-bonded plastic film side over the weakened line area of the easy-to-open cover by bending the side toward the easy-to-open cover. An opening is provided inside the cover that is opened to open the cover and is smaller in diameter than the diameter of the weakened line that is adapted to open when used. The rolled parts are glued together by heating the outer part of the part, which is the provision of a weakened line that is adapted to be unfolded.

German patent application P,2g≠,r5bg,ri discloses a method for sealing glass containers with a synthetic material applied to metal foil. The method includes applying a bonding agent to the edge of the glass container to more firmly attach the metal foil coated with synthetic material to the glass container. The adhesive may be a pure organic or aqueous solution of an alkyltrichlorosilane with a substituent having seven amine groups, an epoxy group, a vinyl group, an acrylo group or a methacrylo group, a pure aqueous solution of an alkyltrialkoxysilane, etc. The organic solution is an aqueous solution or an organic solution of a monomeric or polymeric titanate ester. After the coating is applied and dried, it is applied to a heat sealing head.
The sealing foil is sealed in a known manner by pressing it against the upper edge of the glass container using a head).

Ketones, especially acetone, can be used with alkyltrialkoxysilanes, alkyltrichlorosilanes or mixed alkyl-
Alcoquines are disclosed as preferred organic solvents for chlorosilanes. However, for titanate esters, benzene-based solvent systems are used.

Each solvent system requires the use of volatile organic compounds.

British Patent Specification Letter 1. ! ;3g O≠No. 2 is a glass bottle having a mouth with an upwardly facing surface, a metal foil film heat-sealed to the mouth of the container over the mouth of the container, and a metal foil film that is heat-sealed to the mouth of the container and the top of the container and the foil film. A sealed container is disclosed comprising a plastic snap cap deformable by heat and pressure, wherein the mouth of the container is provided with a raised bead on an upwardly facing surface that extends continuously around the mouth. has been
The camp has a thickness on the upwardly facing surface that is at least twice the height of the bead;
Snack 0 is pressed into the plastic material of the cap. The metal foil film is used as an undercoat for adhesion between the foil film and the container bead at an activation temperature of 27j to 3.2t.
'F may include an ethylene-acrylic acid copolymer.

German patent DE30//7/A entitled ``Method for adhering supports by heat sealing'' based on p30//7/μm1l-3, filed in January, 2013. / Glass to form a package containing dry suit 0, yogurt or similar cold-filled food products
Discloses a method for sealing metal. The container and closure are as follows:

(c) and (d) are secured together by a heat-sealable adhesive produced by hydrolysis and polycondensation of 7: (,) General formula I: RmSIX4. , -m(I) [wherein R is
Alkyl, aryl, alkylaryl represents arylalkyl, and X is hydrogen, halogen, hydroxyl, alkokene, acyloxy or -NR4 (where
′-hydrogen and /l: represents alkyl), m is /
1.2 still takes the value 3].

(b) General formula ■: Silane with a silicon functionality of 5iX4(■) or higher (
In the formula, X has the same meaning as in the above case, but not all of the residues are hydrogen).

(c) Main group of the periodic table that forms soluble, poorly volatile oxides in the reaction medium.
5 secondary groups
p) 7 or more compounds of the elements b i or vb or 7 or more refractory oxides soluble in the reaction medium.

(d) General formula ■: Rn(R″Y), 5iX(4-n-,) (1
10 seven or more organofunctional silanes (wherein R
and
group, phenylene, alkylphenylene or alkylenephenylene may be present in the middle; Y represents a straight-chain alkylene or branched alkylene; substituted amine group, substituted anilino group, aldehyde group, keto group, carboxyl group,
Hydroxyl group, mercapto group, cyan group, hydroxyphenyl group, carboxylic acid group, alkyl ester sulfonic acid group, phosphoric acid group, acryloxy group, methacryloxy group, glycinoloxy group, epoxide group 4 Ta represents a vinyl group, n represents a vinyl group , has the value 0,/or λ, p has the value /,2 or 3, and n + p takes the value /2 or 3). (
Here, the hydrolysis and polycondensation are carried out in the presence of the stoichiometric amount of water required for the hydrolysis and, if provided, in the presence of a condensation catalyst and/or a solvent, in which the starting components (a
) and (d), oligomers of these silanes which are soluble in the reaction medium may also be used).

There are a number of inherent problems when using the above methods in hot-filled applications. For example, the method described above may be used to hot-fill an acidic food such as orenno juice into a glass container using a thin metal closure coated with the plastic material described above, or using the adhesive described above; A number of problems arise when used for hot filling acidic substances such as jelly, jam, tomato sauce, ketchup, etc. Seven critical problems are: - The closure can separate from the heat-sealable adhesive on the end layer of the glass container as early as after the container has been filled, sealed, and transported to the cooling station. During hot-filling, the container is heated with hot-filled contents. heat and pressure seal head
When the e-sealing head seals the closure to the container, it imparts a significant amount of heat to the package. These heat dumps will evaporate some of the water in the cookie.

Such vapor pressure causes the thin metal closure to bulge outward under pressure. Such forces and closure bulges result in premature removal of the closure at an unacceptably high rate. During this latter stage of the cooling process, after the added heat has finally dissipated, some vacuum builds up inside the container and the closure collapses inward. Such a vacuum can be achieved by using a metal foil closure and
This results in increased stress in the seal between the heat sealable adhesive applied to the end lip and the end lip of the glass container. Many seal failures occur when hot fill adhesives and methods are used that are well suited for cold fill applications. Such failure of the seal may result in leakage of the package and still result in contamination of the contents rendering the contents unusable commercially.

Furthermore, during long-term storage for several months to several years, leakage due to the long-term storage instability of adhesives used in contact with foods with high moisture content progresses.
Air pollution enters the food/NON food product, thus rendering it worthless. - This shortcoming in the long-term shelf life of the food product is particularly significant in the case of hot-filled food products, which typically have a long shelf life. In addition, hot-filled food packages have some vacuum inside the container, and this vacuum is created by using thin, flexible metal closures, heat-sealable adhesives, and glass container end lips. places high levels of mechanical stress on the bond between the

Also, many of the above-mentioned adhesives do not exhibit long-term resistance, especially when in contact with fruit juices and tomato-based foods that are quite acidic and have high moisture contents. Therefore, the heat-sealable adhesive itself loses its ability to seal the package upon long-term storage in contact with food under stress. Furthermore, many of the methods currently in use require the application of many individual layers of various solutions, such as adhesives, crosslinkers, binders, etc., to the container end lip. This requires additional processing steps and a significant capital investment in various solutions and machinery. Such solutions are time consuming to formulate, often lack storage stability, and often still contain organic solvents. Such solvents are often not approved for contact with food. Such solvent-based adhesive formulations also require special employee protection and environmental regulatory practices, equipment and procedures, which often limit their use. Clearly, the use of environmental pollution control equipment is detrimental to the low-cost production of everyday hot-fill foods.

Therefore, an easy, reliable and complementary heat-sealable adhesive for hot-fill food packaging applications that provides packages that are simple, reliable, and free of organic evaporation, as well as cooling-stable and long-term storage stable. There is a need in the art for formulations.

It is an object of the present invention to provide a sealed container and a method of manufacturing the same suitable for accommodating hot-filled food products, wherein the container is filled with hot food product and the closure is After installation and cooling to ambient temperature, it shall have a high resistance to the occurrence of leakage.

A further object of the present invention is to provide a sealed container that exhibits high resistance to long-term storage pressure without creating leaks between the heat-sealable adhesive layer and the glass container or thin, flexible closure. An object of the present invention is to provide a method for manufacturing a container suitable for accommodating hot-filled foods.

These and other advantages of the present invention are realized by a method of sealing a glass container, wherein the container has an upper shield terminating at a terminal edge, and wherein the method includes sealing at least one glass container. The method includes the step of heating the end portion of the container to an elevated temperature for a sufficient period of time such that the end portion is heated to a temperature sufficient to oxidize the organic material applied to the end portion. Then apply at least one layer of heat-sealable adhesive to
The heat-sealable adhesive is applied to the upper end groove to form a bond between the thin, flexible metal closure coated with organic thermoplastic material and the upper end lip of the glass container. It's something you get. The heat sealable adhesive according to the present invention is an aqueous mixture of ethylene-acrylic acid copolymer and silane having a melt index of about 300 or less. Following application of the heat-sealable adhesive, the adhesive is allowed to dry and then the thin, non-porous metal-plastic laminate cloth is pressed into a glass container and subjected to heat and pressure using conventional heat-seal pressure application means. Seal with.

Containers formed in accordance with the present invention are particularly suitable for containing hot-filled food products and exhibit high resistance to leakage during the filling, sealing, and cooling processes, as well as during long-term storage and handling. Particularly resistant to leakage.

BRIEF DESCRIPTION OF THE DRAWINGS The present invention will now be further described with reference to the accompanying drawings, in which a glass container, designated as a whole by the reference numeral 10, is shown in partial cross-section. The glass container 10 terminates in an upper end defining an opening to the container 10. Terminating part/! is the terminal main part/≠ at its top. Typically, the end portion /≠ will be flat or slightly rounded, as is common in wide mouth glass containers.

A thin layer of heat-sealable adhesive overlies the end portion of the container. A thin, non-porous, flexible membrane-type closure /K with a complementary shape to the end /2 of the container 10
is located above the container, and the closure/end part/
It can be attached to the terminal end of the container 10 by engaging the closure /g. Typically, the closure/♂ includes a metal foil portion 20 and a thermoplastic heat sealable film portion 22. The heat-sealable film portion 22 itself may be a laminate that is laminated into a structure that will be described in detail below.

In a preferred embodiment of the invention, the heat-sealable adhesive comprises a mixture of a silane compound and an ethylene-acrylic acid copolymer, wherein the ethylene-acrylic acid copolymer is present in the copolymer structure in an amount of 0%. of ethylene and 20% acrylic acid, melt index 3
shall have a value less than 00. The most preferred melt index is about 75. According to the present invention, 75~
Ethylene-acrylic acid copolymers with a melt index between 300 and 300 are suitable for hot-fill food processing without organic solvents in the adhesive.
It has been shown that the present invention provides an excellent high hot tack strength heat sealable adhesive for use in essing.

Melt index, as used herein, is defined as the number of grams of thermoplastic that can be forced through a 0.0 R inch orifice with a force of 271.09 in 70 minutes at 790°C.

A preferred silane compound is Union-Carbide Organofunctional Silane A//, 20 (Union-Car
bideorganofunctional 5ila
ne kl/20), which is N-(beta-aminoethyl)gamma-amino-zorobyl-trimethoxysilane or diamino functional silane. The preferred silanes described above are soluble in water, which makes them particularly suitable for hot-fill food packaging applications where organic solvents are not used in the formulation of heat-sealable adhesives. All components of the adhesive must be suitable for use in contact with food under food and drug regulations and most organic solvents are not permitted. The preferred silane is 1! Specific gravity at j℃/, 0
3, is a straw-colored liquid with a refractive index /, lI-'A I (, nD23 °C) and a flash point, 21rO'F.

Preferred ethylene-acrylic acid copolymers have a melt index of about 300 or less and are capable of forming aqueous, organic solvent-free dispersions at room temperature.

Such resins are available from Dow Chemical Com.
pany to Prodnct A PE '1f3
Currently obtained as . A more preferred resin is an ethylene-acrylic acid copolymer with a melt index of about 7 ta.

Closure/g Metal foil, 20 is thickness/, 2
J mill aluminum metal. A thermoplastic heat-sealable film 22 laminated to the metal foil 20 includes:
E.1. duPont deNemours &Co
5urlyn mater provided by mpany
ial (which is an ethylene-acrylic acid copolymer of the desired melt index) or a nitrocellulose polymer coated with a polyvinyl butyral polymer and contacted with an aluminum Uno film to form an aluminum nitrocellulose-polyvinyl butyral laminate. It may be a laminated structure. Preferred materials include: 5urlyn Grade A/Alr;
2, which is an ionomer resin with a zinc counterion with a melt index j of 0. The three types of closure/g are suitable for use with the improved heat sealable adhesives described herein. Each of the closures disclosed herein exhibits short-term stability upon cooling from high hot fill temperatures to room temperature and exhibits excellent long-term durability without creating a high rate of leakage in the manufactured container. Excellent hot-fill packages can be made with Shida's new adhesive.

The method according to the present invention of preparing and filling container 10 is best illustrated in FIG. processed container supply station,
24 continuously supplies glass containers 10 for use in the method of the invention. The glass containers 10 supplied by the supply station, 2≠, are processed according to conventional glass container manufacturing methods in which the external surfaces of the containers 10 are treated with various thin transparent coatings. Frequently, such containers are treated with tin tetrachloride to form a so-called hot end coating while the container/b is subjected to significant manufacturing heat. The container 10 is further coated with a polyethylene, oleic or other smooth organic coating applied in a so-called cold-end treatment to improve contact scratch resistance. In accordance with the present invention, cold-end treatment substances such as oleic acid are removed or substantially oxidized in the container prior to application of the heat-sealable adhesive layer to achieve optimal results. It has been found that these should preferably be treated.

Flame treatment stage! Party B has at least the terminal groove part of the container 10.
Complete or partial removal of the cold-end treated smooth material is accomplished by exposing the ≠ to a high oxygen content flame to oxidize the cold-end treated material. Typically, a temperature of about 300° F. is applied for a few seconds to effectively remove the bulk of the cold-end treatment material. Further in accordance with the present invention, it has been found that sequential exposure of the termination features to multiple flames improves the long-term storage stability and leakage resistance of the package.

For example, the end groove /4' or so-called mouth of the container 10 is connected to a ribbon-type gas burner arranged in a row that generates an oxygen-enriched gas flame which oxidizes or incinerates the organic components of the said cold-end treatment of the end groove /≠. It is made to pass under the . In a preferred implementation of the invention, three die-type gas burners directed to the end groove /j remove sufficient cold-end material to maintain the heat-sealable adhesive during hot-filling, cooling, and long-term storage. Facilitate the handling of layer/B.

After the flame treatment stage B, the container 10 is preferably placed in a cooling stage 2f, in which the end lip is heated from about 300°C to about 7.20°C/IA0°F. Cool to temperature. Such a low temperature facilitates the application of the heat-sealable adhesive, but does not delay processing of the container 10 by the substantial time required to bring the container 10 to ambient temperature.

Following the cooling step 2g, the glass container 10 is transferred to an adhesive application step 30 where a coat of heat sealable adhesive is applied to the endpoint/ILK to form a thin film approximately 50 microns thick. It is formed. Any conventional application method may be used: however - an overhead roller coa device suitable for continuously applying adhesive to containers 10 arranged in rows;
ting device) is preferred 0 Such an elevated roller applicator consists of a roller of cylindrical rubber (or other elastic material) which coats the end of the container while the end groove /≠ of the container passes underneath. It is biased downward so as to forcibly contact the shield part/≠. The rollers are typically mounted in a direction transverse to the direction of travel of the container;
0.02 min/1n in one contact with terminal groove/≠? /Dry film/It is designed to be applied at about 2 degrees of darkness. Coating weights up to 0.073 m9y2 may be used, but such minimum amounts do not necessarily compensate for surface irregularities in the shape of the termination layer. / 0.073 per charm 2
; Weights exceeding m9 are preferred. The practical upper range is about 0.0 and nvn+112.

Following the adhesive application stage 30, the container is passed to a drying stage 32, where forced drying of the heat sealable adhesive takes place. In a preferred implementation of the present invention, a quartz infrared heater puncture is used in the container 10. Apply 75 microns of radiant energy to raise the temperature of the container to about 0°F in a very short period of time, eg, 6 seconds. Such temperatures thermally dehydrate the adhesive compound to form a strong seal with the end shield/≠.

After the initial coating and drying steps, the resulting article is a glass container with a coat of dried heat seal adhesive on the termination layer. Such articles are storage stable and can be sent as commercial individual articles to a filling plant, or are composite containers that can be filled immediately.

For many applications where food products that are very difficult to store are used, coated and dried containers can be used during the drying stage 3.
2, the adhesive passes through a return loop 33, and the adhesive is applied for the second time. It is recirculated to the adhesive application stage 30 for a dry coating of 0.023 m9//mm2 and the second
A drying phase 32 is again entered for the drying phase in which the second coat of adhesive is dried into firm sealing engagement with the first coat of adhesive. In many applications, it is not necessary to double coat the end shield, but when the end lip is somewhat irregular, as is typically the case with household containers, The λth application of adhesive is required to achieve the best results for excellent seal durability and best long-term storage of the container. Such double coatings were hot-filled (ho
t-filled) yields a container capable of holding high acid content and high moisture content foods, such as fruit juices, with minimal leakage during cooling and long-term storage.

After the container 10 exits the drying stage 32, the container 10 undergoes a hot-fill-cloat application stage shown in FIG.
ring and closure application
ion stage) 3≠. 77 at stage 3≠
0~. Hot food at 210°F is placed in container 10. After filling the container 10 with hot food, a seal is applied to the end shield/≠ to close the conventional seal head (sea
It is sealed to the terminal main part/l by l inghead). In such a seal head, heat and downward pressure are applied to the closure/g, and the thermoplastic heat-sealable film 22 of the closure/♂ is formed into a heat-sealable adhesive layer in close contact with the terminal shield part/≠. /Becomes firmly engaged with Party B. After the container is filled and sealed, it undergoes multiple cooling stages.
770 to 210
Cooled from the lower filling temperature to ambient temperature.

The hot-filled containers are processed in the multi-stage cooling stage 3B to the hot-filled container supply stage 3g, and the hot-filled container supply stage 3g is sent to the -natural hot water treatment stage≠0. Place the containers in a line. The containers arriving from the hot-filled barrel supply 3g typically contain product between 770 and 210 degrees Fahrenheit. - The hot steam treatment step involves subjecting these vessels to hot steam for 7 to 70 minutes at temperatures below about /1 l-0 to igo: typically hot steam for about 3 minutes to a water temperature of /g'θ°C. Apply to. The vessel is sent from -fire hot water treatment≠0 to the secondary hot water treatment stage 1l-2, and this secondary hot water treatment stage 4I
-2, the container lasts for about 7 minutes to about 70 minutes, 10~/!
Exposure to a hot water spray of 0°F, typically for about 3 minutes, at a water spray temperature below about 0°F. The container under 720 is transferred from the secondary hydrothermal treatment stage≠2 to the cold water treatment stage≠≠, where the sealed container is heated for 20-30 minutes. Take a cold water bath or cold water spray.

When hot-fill applications are required for orange juice, ketchup, mustard, tomato stir-fries, tomato sauces, jellies, jams, and similar hot-fill products, the heat-sealable By carrying out the method of the invention together with the adhesive, the sealed container shows excellent leakage resistance during the multi-stage cooling stage 3B, as shown in detail in sub-stage 3g-≠≠, and still has several It has been found that it exhibits excellent resistance to leakage during long-term storage of months to years.

As mentioned above, according to the present invention, the heat-sealable adhesive has a ratio of ethylene content to gO to acrylic acid content. θ
A silane mixed with an ethylene-acrylic acid copolymer having a low melt index of less than 300.

A suitable ethylene-acrylic acid copolymer is a product PE having the following physical properties when purchased as a dispersion:
Dow Chemical in the United States as II-♂3
Available from a l s: solid content (ch)
25 Viscosity (Brookfield) (tOr
pm) 100-200H9-70 Surface tension (Gui7/Crn) ≠Otsu-
≠7 weight/gallon (pound) g,,2
．． :z density (liquid) (, I at 2j'C)9/cC)
OM3 density (solid) (ji at 23 °C
/cc) 0.960 vehicle
ammonia water volatile organic compound
Acid value (Dow) /3 Melt index (ASTM D-7231)
300g/10m1n melting point (Dow, DSC)
I! ;C-(/13 lower,)Picker softening point (A
STM D-7323) 30°C, (/2.2°F,) Ultimate tensile strength ASTM D-Otsu 3K) /
Typically, the silane component of the heat-sealable adhesive is between ≠ and 7.2% by weight as a dry film of the adhesive.

Non-organic solvent-containing adhesives according to the present invention typically contain 23 g of copolymer dispersed in 100 I of water containing about 2 g of silane. Typically, non-solvent containing adhesives are manufactured as in the following example. Aqueous dispersion containing a copolymer, preferably Dow 4t13 as described above
into a mixing vessel and stir at sufficient speed to form a thin layer. Minimum thickness is desirable, since high velocity swirling results in significant air infiltration of the dispersion. After a slight swirl has formed in the copolymer dispersion water, 3 parts by volume of ammonia hydroxide in 3 g% by weight are added.
Add per part by volume of copolymer dispersion/θO. The ammonium hydroxide is first poured slowly into the spool to promote proper mixing of the ammonium hydroxide into the copolymer dispersion to aid in the formation of a stable emulsion. next! Capacity of silane, preferably Union-Carbid
e A//20 silane is slowly added per 100 parts by volume of copolymer dispersion so that the silane is poured into the mixture. The mixture is stirred slowly for 1.2-3 minutes to create a minimal thinning to form a heat-sealable adhesive layer according to the invention when applied to the end groove of a glass container. to form a stable non-organic solvent-containing dispersion. In high-speed application lines, the adhesive mixture is foamed during application by high-speed rollers. In such a case, after the addition of the silane, / parts by weight of ammonium hydroxide are added with stirring and the resulting adhesive is stirred for 2 to 3 minutes.

The following tests were conducted to demonstrate the superior durability of packages according to the invention.

Seventy-seven wide-mouth glass containers were coated with near 00 volume parts of Dow Chemical (2 coats) with an adhesive having the composition shown below.
Copolymer 47-13 of U, S, A, (in deionized water); all ingredients were added in this order and conditions were as described above. Apply adhesive to these 77 containers.

After applying the coated container in the first adhesive application step 30,
Heat for 3 minutes under /≠θ. After the intended application of adhesive via return loop 33, the container is heated to 200 DEG F. for 4 Lj minutes.

The coated container is immersed in a /II-'0°F water bath to simulate a commercial hot fill line container preheater. Next, fill a second container with 210°F orange juice.

A preshaped 2 mil aluminum closure with a 5 urlyn undercoat is positioned over the container and heat sealed with a conventional heat-pressure sealing head. The conditions for sealing are as follows: Seal surface temperature 3g3; -1lO temperature
Seal pressure Clip pressure at the edge of the lip 3. Tanogur seal time
After a 7 second seal, the container is cooled in a 7gO°F steam chamber for 3 hours. The container is then cooled with a 20°F water spray for 3 minutes. Finally, the container is cooled for 3 minutes with a stream of water at 7.2°F. The leak was an undetected force).

After cooling to 72"F, the sealed container is placed in a vacuum desiccator. A vacuum equivalent to a mercury finch is applied to the vacuum desiccator and held for 7 minutes. The vacuum is maintained at 26 inches of mercury for 5 seconds. No leaks were detected.

This test demonstrates the durability under reduced pressure and cooling durability of the tubes according to the present invention.

A second test demonstrates the durability of the cage according to the present invention when subjected to hot filling, first and second heat treatments, and cold water treatment in a commercial food packaging operation. I did it for the sake of

The heat-sealable adhesive dispersion is prepared as follows: 103 m1 of ethylene-acid copolymer type PE-'1-13 is stirred to form a swirl as mentioned above. ．． of ammonium hydroxide is slowly added to the swirl of the stirred copolymer dispersion. Next, 70m1 Uni
on-Carbide organofunctional silanthizo A//2
Stir θ into a whirlpool of solution.

In addition, 210 ml of a solution consisting of 1/vol. ammonium hydroxide and 700 vol. distilled water is added to the above solution to reduce foaming during application when using a roller system as described above.

Next, 73 wide-mouthed containers were coated twice with the adhesive dispersion using the roller coating means as described above, to give a coating of 0.03 m9.
/raa2 layer of dry adhesive is formed. The first coat of heat-sealable adhesive was dried for 75 minutes at /1l-0°F, and the second coat was dried at 20°F.
Dry for 1-3 minutes and cool the container to room temperature after each drying cycle.

Prior to filling with hot-filled product, each container is immersed in a water bath under /'l-0 to simulate bottle warming equipment on a commercial filling line. Next, fill the container with 770 ml of strawberry jelly until it overflows. Next, 5u on the back side
It's an aluminum foil claw as described above with an undercoat of RLYN ionomer resin.
Place the bottle at the mouth of the container.

The closure is heat sealed with a conventional heat-pressure sealing head under the same conditions as defined in the previous example. After the sticker, /I! i>0°F hot water 1st hydrothermal treatment stage 1l
Forced cooling at -0 for 3 minutes. Next, the container! is sent to a hydrothermal treatment stage ≠ 2 where it is subjected to a water spray below /20 for 3 minutes. The container is then sent to the cold water treatment stage Il-≠, 7. ! Expose to i″°F cold water flow for 3 minutes. All containers are then cooled to room temperature in ambient air.

After cooling to ambient temperature, the sealed container is placed in a vacuum desiccator for testing. During the test, rupture of the seal becomes evident with the generation of air bubbles from the package. Each container is placed in a vacuum desiccator filled with water and subjected to a vacuum applied for 7 minutes to correspond to a finch of mercury. After this 7 minute period, the vacuum is increased to 2 inches of mercury and held for 5 minutes.

As a result of the above test, 72 out of 73 containers withstood both low and high vacuum test conditions.

Only 7 did not survive the test due to cracks in the glass wall of the container.

Seven more tests were conducted to determine the long-term shelf life of the package. In this test, /11- containers were filled with 270 g of orange juice and sealed as described above. The containers were then tested under a finch vacuum for 7 minutes as described above and then for 5 seconds under a 2 inch vacuum as described above.

None were damaged. Next, put the sealed container into
Stored in an accelerated aging room at 100°F for 22 days.

7 days in an accelerated aging chamber at /00'F roughly corresponds to 3 days under normal use conditions. After long-term storage, all containers were again subjected to the Finch Vacuum Dry Storage Test for 7 minutes. After the above long-term storage, no leakage was detected in any of the /≠ containers.

[Brief explanation of drawings]

FIG. 1 is an exploded view of the heat sealable adhesive coated upper end of the glass container and the nonporous metal foil/thermoplastic film laminate flexible closure. FIG. 2 shows a schematic representation of the method of the present invention for manufacturing, filling and sealing a package according to the present invention. FIG. A method for cooling the partially filled volume 6 is shown schematically. 10...Glass container, /2...Upper end, /≠
...Terminal part, /B...1j before adhesion that can be heat-sealed, /♂...Closure, 20...Metal foil part. Agent's name: Kawahara 1) - Ho

Claims (1)

Claims: (1) A method of sealing the end of a glass container having an upper termination layer, comprising: a. applying a layer of heat-sealable adhesive to the upper termination layer; Possible adhesives include a mixture of a silane and an ethylene-acrylic acid copolymer, the copolymer having a melt index of about 300 or less; b. a layer of the heat sealable adhesive on the end lip; C1 filling the container with hot food product; d applying a thin, flexible, non-porous closure to the end lip and applying heat to the closure to the end lip; applying pressure, the closure comprising a first upper metal layer and a second lower thermoplastic layer, the thermoplastic layer being in contact with a heat sealable adhesive. A method of sealing the end of a glass container having said upper end layer. (2. The method described in claim 1, wherein the container is entirely made of glass. (3) Claim 1 4. The method according to claim 1, wherein the heat sealable adhesive layer has an ogrn9 of 0.0076 to ogrn9 per end layer surface area/wn2. The method of claim 1, wherein the silane is a diamino functional silane. (5) The method of claim 1. in which the noamino functional silane is N-(beta-aminoethyl)
A method according to claim 1, characterized in that it is gamma-amino-propyl-trimethoxysilane. (6) The method of claim 1, wherein the copolymer is about 7',! and having a melt index of from about 300 to about 300.
The method described in section. (7) The method according to claim 1, wherein the copolymer contains in its structure gO% ethylene and 20% acrylic acid. Method described. (8) The method according to claim 1, wherein the adhesive is dried by irradiation with infrared rays. (9) The method according to claim 1, wherein the thermoplastic layer is an ethylene-acrylic acid copolymer. α0 The method of claim 1, wherein the thermoplastic layer is a first sublayer of nitrocellulose applied to the aluminum and a second sublayer of polyvinyl butyral applied to the first sublayer. The method according to claim 7, characterized in that: α force In the method according to claim 1, the α force of the adhesive is and applying a layer of the first step to the terminal lip prior to filling the container with the hot food product. A method according to claim 1, characterized in that it includes the step of drying the layer of. Alpha force In a method of manufacturing a composite container having a glass termination, the termination having an upper termination lip, the method comprises: a. applying a layer of heat-sealable adhesive to the upper termination lip; the adhesive comprises a mixture of silane and an ethylene-acrylic acid copolymer, the copolymer having a melt index of about 30θ or less; b. drying the layer of heat-sealable adhesive on the termination shoulder; The method for manufacturing the composite container, comprising the steps of: α-Bu The method according to claim 72, wherein the heat-sealable adhesive layer has a termination layer surface area/TMn
73. The method of claim 72, wherein θ is ogmy from 90.0075 to 2. α◆ The method of claim 72, wherein the silane is a noamino functional silane. α Force The method of claim 74/-, characterized in that the diaminofunctional silane is N-(beta-aminoethyl)gamma-amino-zorobyl-trimethoxysilane. The method described in Section 1≠. Alpha Force The method of claim 11, wherein the copolymer has a melt index of 7 Ta to 300. alpha force The method of claim 72, wherein the copolymer has in its structure 0 and 20
and acrylic acid according to claim 7.2. The method described in section. 0. In the method according to claim 1 = 2,
13. A method according to claim 12, characterized in that the adhesive is dried by irradiation with infrared radiation. (1) The method of claim 72, comprising the steps of applying a second layer of adhesive to the terminal lip and drying the second layer. 7.2. A single hollow container with an upper glass body having an upper terminal lip; and a layer of heat-sealable adhesive on the terminal shoulder. , wherein the adhesive contains a mixture of silane and an ethylene-acrylic acid copolymer, and the copolymer has a melt index of 300 or less. (c) Claim 20 In the container, the adhesive layer has an end groove surface area/mm2 of 0.007
21. The container according to claim 20, characterized in that the container is 3 to o, o g'. (a) The container according to claim 20, wherein the silane is a diamino functional silane.翰 The container according to claim 22, wherein the diamino functional silane is N-(beta-aminoethyl) gamma aminozolopyrutrimethoxysilane, 2.2 Container described in 2. (c) In the container according to claim 20,
21. Container according to claim 20, characterized in that the copolymer has a melt index of 7j to 3000. (c) The container according to claim 20, wherein the copolymer has ethylene of gos and 20% of the copolymer in its structure.
% of acrylic acid. (c) A method of manufacturing a hot-filled food product comprising a glass container, a claw shear, and a heat-sealable adhesive sealing the closure to the container, the container having an upper end lip. a. applying a layer of a heat-sealable adhesive to the end lip, the heat-sealable outer adhesive comprising a mixture of Cassisint, an ethylene-acrylic acid copolymer, and the copolymer having a molecular weight of about 300 or less; b. drying the layer of heat-sealable adhesive on the termination layer; C. filling the container with hot food product; d. applying a non-porous claw gloss to the terminal lip;
applying heat and pressure to the closure to the end lip, the closure including a first upper metal layer and a second lower thermoplastic layer, the thermoplastic layer being a heat sealable adhesive. e. contacting the sealed container with water for / to 70 minutes, the water being at a temperature /4'θ~710T; f. ~7.20
contact with water at a temperature of 70°F for a period of 70 minutes;
A method for producing a hot-filled food package as described above, characterized in that the method comprises the step of contacting with water at a temperature of 20 to 30 minutes. B) The method according to claim 2B, wherein the heat-sealable adhesive layer has a surface area of terminal layer/2 parts of 1
) 0.007j to O0θg■! The method described in Section 4. (c) The method according to claim 2B, wherein the silane is a diamino functional silane.翰 The method according to claim 2g, characterized in that the noamino functional silane is N-(beta-aminoethyl)gamma-amino-propyl-trimethoxysilane. The method described in section. (B) In the method described in Claims No. 2 and B,
Claim 21, wherein the copolymer has a melt index of about 7 Ta to about 300.
．． The method described in section. 01) The method according to claim 2B, wherein the copolymer contains gO% of ethylene and 20% of ethylene in its structure.
% of acrylic acid. 02. The method according to claim 2B, wherein the adhesive is dried by irradiation with infrared rays. 0→ In the method described in claim No. 2j,
6. A method according to claim 6, characterized in that the thermoplastic layer is an ethylene-acrylic acid copolymer. 04 In the method described in claim 2 B,
A thermoplastic layer was applied to a first sublayer of nitrocellulose applied over the metal layer and the first sublayer. 71
The method according to claim 2B, characterized in that the second lower layer is J vinyl butyral. 0→ The method of claim λ6, comprising applying a second layer of adhesive to the end lip and drying the second layer prior to filling the container with the hot food product. A patent characterized in that it includes the step of