Sealing member and manufacturing method therefor

Abstract

The present invention relates to a sealing member and, more specifically, to a sealing member installed on a vessel closure in order to seal a vessel when the vessel closure is coupled to a vessel inlet, and a manufacturing method therefor. The present invention provides a sealing member comprising: a first film having a close-contact surface that is in close contact with the vessel inlet and having formed thereon a shielding layer for shielding moisture and for an oxygen shield layer; and a second film having a lower density than the first film so as to be coupled to the close-contact surface of the first film and provide a buffer force to the vessel inlet.

Description

Sealing member and manufacturing method thereof

[0001] The present invention relates to a sealing member, and more particularly, to a sealing member that is installed on a container closure and seals the container when the container closure is coupled to the container inlet, and a method for manufacturing the same.

[0002] Typically, containers for beverages such as lactic acid bacteria beverages are equipped with a container stopper at the container entrance to prevent the contents stored in the container from leaking out without permission.

[0003] In particular, a sealing member is additionally installed at the entrance of the container to prevent the contents stored in the container from leaking or spoiling.

[0004] Meanwhile, a sealing member is attached to at least one of the container inlet and the container stopper to prevent the contents stored inside the container from leaking out or being spoiled.

[0005] Patent Document 1 is an example of a conventional sealing member, in which an adhesive layer is formed to be attached to a container inlet or a container stopper to increase sealing power, including an aluminum foil layer.

[0006] However, conventional sealing materials have a problem in that they are formed of various materials, including an aluminum foil layer, and thus have limitations in recycling through collection after use.

[0007] Furthermore, there is a problem that manufacturing costs also increase as it is formed of multiple materials, including an aluminum foil layer.

[0008] (Patent Document 1) KR 10-2024-0031541 A

[0009] The purpose of the present invention is to provide a sealing member and a manufacturing method thereof that are made only of synthetic resin, are recyclable, and have a simple structure, thereby significantly reducing manufacturing costs.

[0010] The present invention has been created to achieve the above-described object of the present invention, and provides a sealing member characterized by including a first film having a contact surface that is in close contact with a container entrance and having a barrier layer for moisture barrier and oxygen barrier formed thereon; and a second film having a lower density than the density of the first film so as to be bonded to the contact surface of the first film and provide a buffering force for the container entrance.

[0011] The above first film can be formed by mixing and melting LLDPE, LDPE, and HDPE, and then the barrier layer can be coated on the contact surface.

[0012] The above first film is formed by a plurality of composite films formed by mixing and melting LLDPE, LDPE, and HDPE, and the barrier layer can be formed between the plurality of composite films.

[0013] The second film can be laminated with the first film immediately after the blocking layer is formed on the first film.

[0014] It is preferable that the above LLDPE is 30 to 60 parts by weight, the above LDPE is 5 to 25 parts by weight, and the above HDPE is 5 to 40 parts by weight.

[0015] The above first film may additionally include TiO2.

[0016] It is preferable that the above TiO2 is 5 to 25 parts by weight.

[0017] The thickness after the first film and the second film are combined is preferably 40 to 500 μm.

[0018] The above second film can be bonded to the first film by dry laminating using an adhesive.

[0019] A third film having the same material as the second film may be additionally bonded to the reverse side opposite the adhesive surface of the first film.

[0020] The above third film can be bonded to the first film by dry laminating using an adhesive.

[0021] The above second film can be bonded to the first film by extrusion lamination using PE.

[0022] The first film may have a PE film bonded to the reverse side, which is the opposite side of the adhesive surface, when the second film is bonded.

[0023] A third film having the same material as the second film may be additionally bonded to the reverse side opposite the adhesive surface of the first film.

[0024] The above third film can be bonded to the above first film by extrusion lamination using PE.

[0025] The present invention also provides a method for manufacturing a sealing member that is in close contact with a container entrance having the above-described configuration, characterized in that the sealing member is manufactured by bonding a second film having a lower density than the density of the first film to the close contact surface of the first film, which has a contact surface that is in close contact with the container entrance and has a barrier layer for moisture barrier and oxygen barrier formed thereon, so as to provide a buffering force for the container entrance.

[0026] The sealing member and the manufacturing method thereof according to the present invention have the advantage of maximizing recyclability and simplifying the manufacturing process by being composed of only synthetic resin in a configuration of multiple layers, i.e., multiple films.

[0027] In addition, the sealing member and the manufacturing method thereof according to the present invention have the advantage of minimizing deterioration of contents stored inside the container by including a first film coated with a special layer for moisture blocking and further oxygen blocking.

[0028] Hereinafter, a sealing member and a manufacturing method thereof according to the present invention will be described.

[0029] A sealing member according to the present invention comprises a first film having a contact surface that is in close contact with a container entrance and having a barrier layer formed thereon for moisture barrier properties and oxygen barrier properties; and a second film having a lower density than the density of the first film and bonded to the contact surface of the first film to provide a buffering force for the container entrance.

[0030] The above first film is a film having a contact surface that adheres closely to the container entrance and coated with a barrier layer for moisture and oxygen barrier properties. Any film that can be bonded to the container entrance and block moisture and oxygen from entering the container is possible.

[0031] In particular, the first film is a high-barrier PE film, which can be formed by mixing and melting LLDPE, LDPE, and HDPE, and then coating the barrier layer on the contact surface.

[0032] More specifically, the LLDPE may be 30 to 60 parts by weight, the LDPE may be 5 to 25 parts by weight, and the HDPE may be 5 to 40 parts by weight.

[0033] Meanwhile, the first film formed by mixing and melting LLDPE, LDPE, and HDPE is transparent, and if necessary, the first film can be formed to be opaque by additionally including TiO2.

[0034] At this time, the above TiO2 may be 5 to 25 parts by weight.

[0035] Meanwhile, the thickness of the first film having the above-described configuration can be 40 to 500 μm.

[0036] 1. First film

[0037] A. Manufacturing of composite films

[0038] Composite films are produced in a blow-type tubular extruder.

[0039] At this time, in the case of transparent films, the composition of composite films can be LLDPE (50-60%) + LDPE (20%) + HDPE (20-30%).

[0040] Additionally, for opaque films, the composition of the composite film can be LLDPE (40-50%) + LDPE (10%) + HDPE (10-20%) + TiO2 (10-20%).

[0041] At this time, the MI (melt index) of LLDPE is preferably 1 to 2 g / 10 min, density 0.92, and melting temperature 110 to 120°C, the MI (melt index) of LDPE is preferably 1 to 3 g / 10 min, density 0.92 g / cm3, and melting temperature 110 to 120°C, and the MI (melt index) of HDPE is preferably 2 to 4 g / 10 min, density 0.92 g / cm3, and melting temperature 110 to 120°C.

[0042] Meanwhile, considering that the sealing member according to the present invention can be used in a container containing edible beverages such as milk, the composite film must be a product that complies with the 21 CFR 177.1520 (c) 2.1 regulation of the U.S. FDA, considering that it can be used for food.

[0043] The composite film manufactured by the above method can be a transparent or milky film with an overall thickness of 40 to 500 μm.

[0044] Me, formation of a barrier layer

[0045] The composite film manufactured as described above can have a barrier layer formed on at least one of the adhesion surface and the back surface thereof, preferably the adhesion surface, by gravure coating.

[0046] Specifically, by gravure coating a barrier resin, i.e. a liquid resin, on at least one of the surface, adhesion surface, and back surface of the composite film manufactured as described above, a first film having oxygen barrier properties (5 cc / m2.day, atm or less) and moisture barrier properties (5 g / m2.day or less) can be manufactured.

[0047] At this time, the coating layer can be formed on the first film by gravure coating at the same time as the second film is combined, that is, the second film can be combined by dry laminating.

[0048] Meanwhile, liquid materials for providing moisture and oxygen barrier properties may include PVDC (Polyvinylidene chloride), PVA (Polyvinyl Alcohol), PTFE (Polyvinylidene Fluoride), Nano-Silica (SiO2), denatured alcohol, denatured acrylic, and denatured urethane, and can be formed by applying a thin film (1 to 5 μm thick) to a composite film using the gravure coating method.

[0049] Meanwhile, the coating layer may be formed by vacuum deposition of a ceramic material such as SiO2 or Al2O3, as another example.

[0050] At this time, the thickness of the coating layer is preferably 1㎛ or less.

[0051] Meanwhile, the first film may be formed by laminating two or more composite films, i.e., a plurality of composite films, and in this case, the coating layer is preferably formed between the plurality of composite films.

[0052] 2. Merge with the second film

[0053] The second film is a film having a lower density than the density of the first film so as to be bonded to the contact surface of the first film and provide a cushioning force to the container entrance, and various configurations are possible.

[0054] As an example, the second film may be low-density polyethylene foam (LDPE Foam).

[0055] At this time, low-density polyethylene foam (LDPE Foam) is an environmentally friendly, safe foam that is manufactured using chemical crosslinking or electron radiation crosslinking equipment based on LDPE (Low Density Polyethylene) and does not contain dicarbonamide (ADCA) among the foaming or blowing agents.

[0056] And LDPE can be used with excellent MI (melt index) of 4~7g / 10min, density of 0.91~0.92g / ㎤, melting temperature of 100~110℃, extrusion foaming processability, flexibility, shock absorption, etc.

[0057] Furthermore, considering that the second film can be used for food, it is preferable that it be a product that complies with the regulations of 21 CFR 177.1520 (c) 2.1 of the U.S. FDA.

[0058] And it is preferable that the thickness of the second film is in the range of 50 to 2,500㎛.

[0059] Meanwhile, the second film can be combined with the first film by various methods.

[0060] As an example, the second film can be bonded to the first film by dry laminating using an adhesive.

[0061] At this time, as previously explained, the second film can be combined, i.e., laminated, with the formation of a barrier layer on one side of the first film.

[0062] Additionally, a third film having the same material as the second film may be additionally bonded to the reverse side opposite the adhesive surface of the first film.

[0063] Here, the first film may have a PE film bonded to the reverse side, which is the opposite side of the adhesive surface, when the second film is bonded instead of the third film.

[0064] And the third film is a sealing member characterized in that it is bonded to the first film by dry laminating using an adhesive.

[0065] Meanwhile, the second film can be bonded to the first film by extrusion lamination using PE.

[0066] At this time, a third film having the same material as the second film may be additionally bonded to the reverse side, which is the opposite side of the adhesive surface of the first film.

[0067] In particular, the third film can be bonded to the first film by extrusion lamination using PE.

[0068] a. Dry Laminating

[0069] First, the adhesive for dry laminating is a two-component polyester urethane adhesive with excellent heat resistance, cold resistance, and solvent resistance, and can be composed of a mixed ratio of the main agent (polyester urethane) + curing agent (polyisocyanate) + solvent (ethyl acetate).

[0070] Specifically, the composition of the adhesive of one embodiment is as follows.

[0071] Subject (polyester urethane) 45-50%

[0072] Hardener (polyisocyanate) 5-10%

[0073] Solvent (Ethyl Acetate) 30~40%

[0074] Here, the second film, low-density polyethylene foam (LDPE Foam), and the first film, high-barrier PE film, are dry-laminated and cured using the adhesive described above, i.e., polyester urethane adhesive with a diluted solid content (30-35%).

[0075] B. Extrusion Laminating

[0076] As another method of attaching the first film and the second film, a sealing member can be manufactured by extruding and laminating PE, i.e. LDPE resin, in an extrusion limating facility.

[0077] At this time, the LDPE has a melting index (MI) of 7 to 8 g / 10 min, a density of 0.92, a melting temperature of 105 to 110°C, excellent extrudability and adhesiveness. Considering that it can be used for food, a product that conforms to the 21 CFR 177.1520 (c) 2.1 regulations of the US FDA is desirable.

[0078] Accordingly, the second film, low-density polyethylene foam (LDPE Foam), and the first film, high-barrier PE film, can be thermally laminated using LDPE extruded resin instead of an adhesive.

[0079] Here, the extrusion temperature is 380~340℃, the LDPE thickness is 15~30㎛, and the extrusion speed is 100~150m / min.

[0080] It can be done with conditions.

[0081] Meanwhile, a sealing member manufactured with the above structure can have a preset pattern printed on its surface, particularly on the back side.

[0082] The printed pattern can be formed into various patterns such as letters, symbols, shapes, and pictures, such as manufacturer's mark, recyclable mark, etc.

[0083] Meanwhile, the printing of the pattern can be performed by gravure ink, and as gravure ink, a combination of urethane + vinyl mixed ink (for surface printing) can be used.

[0084] And, when printing on a gravure printer, it can be applied by dividing it into one-component type (without hardener) and two-component type (with hardener) depending on whether or not a hardener is used.

[0085] Meanwhile, after the printing process, the drying temperature: 80~100℃, printing speed: 50~150m / min, color: 1~9 colors can be used, and the printed surface can be PE foam or PE film surface.

[0086] - Configuration example

[0087] The combined structure of the first film and the second film described above can have various embodiments depending on the printing layer, lamination method, etc., and the embodiments are as follows.

[0088] Print 1~5㎛PE foam 50~2,500㎛Adhesive 1~10㎛High barrier PE film 40~500㎛Adhesive 1~10㎛PE foam 50~2,500㎛

[0089] Multilayer (double-sided foam dry laminating printing)

[0090] 15 to 70 parts by weight of low-density polyethylene foam (LDPE Foam)

[0091] High barrier PE film (LLDPE, LDPE, HDPE, barrier resin (barrier layer) composite) 10-25 parts by weight

[0092] Adhesive 1-3 parts by weight

[0093] 1-2 parts by weight of gravure ink

[0094] PE foam 50~2,500㎛ Adhesive 1~10㎛ High barrier PE film 40~500㎛ Adhesive 1~10㎛ PE foam 50~2,500㎛

[0095] Multi-layer (double-sided foam dry lamination, no printing)

[0096] 15 to 70 parts by weight of low-density polyethylene foam (LDPE Foam)

[0097] 10-25 parts by weight of high-barrier PE film (LLDPE, LDPE, HDPE, barrier resin composite)

[0098] Adhesive 1~5 parts by weight

[0099] Printed 1~5㎛PE foam 50~2,500㎛PE 15~30㎛High barrier PE film 40~500㎛PE 15~30㎛PE foam 50~2,500㎛

[0100] Multilayer (double-sided foam extrusion laminating printing)

[0101] 15-60 parts by weight of low-density polyethylene foam (LDPE Foam)

[0102] 10-25 parts by weight of high-barrier PE film (LLDPE, LDPE, HDPE, barrier resin composite)

[0103] 5-10 parts by weight of low-density polyethylene (LDPE)

[0104] Gravure ink 1 to 5 parts by weight

[0105] PE foam 50~2,500㎛PE 15~30㎛High barrier PE film 40~500㎛PE 15~30㎛PE foam 50~2,500㎛

[0106] Multilayer (double-sided foam extrusion laminating without printing)

[0107] 15 to 65 parts by weight of low-density polyethylene foam (LDPE Foam)

[0108] 10-25 parts by weight of high-barrier PE film (LLDPE, LDPE, HDPE, barrier resin composite)

[0109] 5-10 parts by weight of low-density polyethylene (LDPE)

[0110] Print 1~5㎛ high barrier PE film 40~500㎛ adhesive 1~10㎛ PE foam 50~2,500㎛

[0111] Multilayer (single-sided foam dry laminating printing)

[0112] 15-60 parts by weight of low-density polyethylene foam (LDPE Foam)

[0113] 10-30 parts by weight of high-barrier PE film (LLDPE, LDPE, HDPE, barrier resin composite)

[0114] Adhesive 1~5 parts by weight

[0115] Gravure ink 1 to 5 parts by weight

[0116] High barrier PE film 40~500㎛, adhesive 1~10㎛, PE foam 50~2,500㎛

[0117] Multilayer (no single-sided foam dry laminating printing)

[0118] 15 to 65 parts by weight of low-density polyethylene foam (LDPE Foam)

[0119] 10-30 parts by weight of high-barrier PE film (LLDPE, LDPE, HDPE, barrier resin composite)

[0120] Adhesive 1~5 parts by weight

[0121] Printed 1~5㎛PE 15~30㎛High barrier PE film 40~500㎛PE 15~30㎛PE foam 50~2,500㎛

[0122] Multilayer (single-sided foam extrusion laminating printing)

[0123] 15 to 55 parts by weight of low-density polyethylene foam (LDPE Foam)

[0124] 10-30 parts by weight of high-barrier PE film (LLDPE, LDPE, HDPE, barrier resin composite)

[0125] 5-10 parts by weight of low-density polyethylene (LDPE)

[0126] Gravure ink 1 to 5 parts by weight

[0127] PE 15~30㎛ high barrier PE film 40~500㎛ PE 15~30㎛ PE foam 50~2,500㎛

[0128] Multilayer (no single-sided foam extrusion laminating printing)

[0129] 15 to 65 parts by weight of low-density polyethylene foam (LDPE Foam)

[0130] 10-25 parts by weight of high-barrier PE film (LLDPE, LDPE, HDPE, barrier resin composite)

[0131] 5-10 parts by weight of low-density polyethylene (LDPE)

[0132]

[0133] The test results of the examples illustrated in Tables 1 to 8 described above are as shown in Tables 9 to 12.

[0134] <Experiment 1> Oxygen permeability and moisture permeability tests

[0135] Example (Table) Oxygen permeability (cc / m2.day.atm) Moisture permeability (g / m2.day) 15 or less 5 or less 25 or less 5 or less 35 or less 5 or less 45 or less 5 or less 55 or less 5 or less 65 or less 5 or less 75 or less 5 or less 85 or less 5 or less

[0136] <Experiment 2> Airtightness test

[0137] Example (Table) Airtightness (gapping) Airtightness (re-capping) 1650mmHg No more than 650mmHg No more than 2650mmHg No more than 650mmHg No more than 3650mmHg No more than 650mmHg No more than 4650mmHg No more than 650mmHg No more than 5650mmHg No more than 650mmHg No more than 6650mmHg No more than 650mmHg No more than 7650mmHg No more than 650mmHg No more than 8650mmHg No more than 650mmHg No more than

[0138] <Experiment 3> Heavy metal, environmental hormone, and residual material and elution test

[0139] Test Inspection Items Implementation Example (Table 1-8) Test Specification (Standard) Material Test PCBs (mg / kg) Not detected Suitable Lead (mg / L) Not detected Suitable Formaldehyde Not detected Suitable Elution Test Potassium permanganate consumption (mg / L) 1 or less Suitable Total evaporation residue elution (4% acetic acid) 5 or less Suitable Total evaporation residue elution (n-heptane) 10 or less Suitable Total evaporation residue elution (20% ethanol) 2 or less Suitable

[0140] <Experiment 4> Liquid preservation test in containers

[0141] Example (Table 7) Application (Table 8) Application Milk Good for 20 days of refrigerated storage Good for 20 days of refrigerated storage Juice Good for 20 days of refrigerated storage Good for 20 days of refrigerated storage Pesticide Good for more than 1 year Good for more than 1 year Engine oil Good for more than 1 year Good for more than 1 year Water Good Good Water + dye Good Good

[0142] The above is only a description of some of the preferred embodiments that can be implemented by the present invention, and as is well known, the scope of the present invention should not be construed as being limited to the above embodiments, and the technical idea of ​​the present invention described above and the technical idea that shares its basis are all included in the scope of the present invention.

Claims

1. A first film having a contact surface that adheres closely to the container entrance and having a barrier layer formed thereon for moisture barrier and oxygen barrier; A sealing member characterized in that it includes a second film having a lower density than the density of the first film so as to be bonded to the contact surface of the first film and provide a cushioning force for the container entrance.

2. In claim 1, The above first film, A sealing member characterized in that the barrier layer is coated on the contact surface after being formed by mixing and melting LLDPE, LDPE, and HDPE.

3. In claim 1, The above first film, A sealing member formed by melting and mixing LLDPE, LDPE, and HDPE, and characterized in that the barrier layer is formed between the plurality of composite films.

4. In claim 2, A sealing member characterized in that the second film is laminated with the first film immediately after the blocking layer is formed on the first film.

5. In any one of claims 2 to 4, A sealing member characterized in that the LLDPE is 30 to 60 parts by weight, the LDPE is 5 to 25 parts by weight, and the HDPE is 5 to 40 parts by weight.

6. In claim 5, A sealing member characterized in that the first film further comprises TiO2.

7. In claim 6, A sealing member characterized in that the above TiO2 is 5 to 25 parts by weight.

8. In any one of claims 1 to 7, A sealing member characterized in that the thickness after the first film and the second film are combined is 40 to 500 μm.

9. In any one of claims 1 to 7, A sealing member characterized in that the second film is bonded to the first film by dry laminating using an adhesive.

10. In any one of claims 1 to 7, A sealing member characterized in that a third film having the same material as the second film is additionally bonded to the reverse side opposite the adhesion surface of the first film.

11. In claim 10, A sealing member characterized in that the third film is bonded to the first film by dry laminating using an adhesive.

12. In any one of claims 1 to 7, A sealing member characterized in that the second film is bonded to the first film by extrusion lamination using PE.

13. In any one of claims 1 to 7, The above first film is a sealing member characterized in that a PE film is bonded to the reverse side, which is the opposite side of the adhesion surface, when the above second film is bonded.

14. In any one of claims 1 to 7, A sealing member characterized in that a third film having the same material as the second film is additionally bonded to the reverse side opposite the adhesion surface of the first film.

15. In claim 14, A sealing member characterized in that the third film is bonded to the first film by extrusion lamination using PE.

16. A method for manufacturing a sealing member that adheres closely to the container entrance, A method for manufacturing a sealing member, characterized in that the method comprises manufacturing the sealing member by bonding a second film having a lower density than the density of the first film to the contact surface of the first film, the second film having a contact surface that is in contact with the container entrance and having a barrier layer for moisture barrier and oxygen barrier so as to provide a buffering force for the container entrance.