WO2007018054A1

WO2007018054A1 - Sealed container

Info

Publication number: WO2007018054A1
Application number: PCT/JP2006/314986
Authority: WO
Inventors: Masaki Nakaya
Original assignee: Kirin Beer Kabushiki Kaisha
Priority date: 2005-08-05
Filing date: 2006-07-28
Publication date: 2007-02-15
Also published as: CN100594164C; KR20080034911A; AU2006277421B2; KR101248725B1; JP2007039115A; AU2006277421A1; RU2008108522A; JP4833608B2; CN101238041A; RU2381160C2

Abstract

A sealed container such as beverage and food containers having lids sealed by laser beam welding and thermal fusing to impart high applicability to impurities, increase sealability, and increase a joining strength between a container body and a lid. The sealed container comprises the container body (1) having a mouth part (9) and the lid (3) causing a deformation therein when it closes the mouth part (9), producing a fitted portion (4) forming a seam in a pressurized state on the container body (1) by a strain stress, and formed of a plastic material. The fitted portion (4) is thermally fused.

Description

Specification

Sealed container

Technical field

TECHNICAL FIELD [0001] The present invention relates to a sealed container in which a lid attached to a mouth of a container body is hermetically sealed by heat fusion, and particularly relates to a structure of the mouth and the lid.

Background art

[0002] Various containers such as bottles, cans, and plastic containers are known as sealed containers, for example, beverage containers. In recent years, cans and plastic containers have come to be widely used because of their convenience in terms of good handling and the like.

[0003] With regard to plastic containers, it is difficult to carry out the tightening process, and plastic containers that are sealed by being tightened like metal can containers for beverages should be distributed. Among plastic containers, the most widely distributed containers are PET (polyethylene terephthalate) bottles. In PET bottles, the method of screwing a cap into the bottle mouth is used as the sealing method. However, this cap is a significant cost increase factor in the entire container. Furthermore, since the cap is mainly made of PP (polypropylene), it is an obstacle to recycling.

[0004] In recent years, bottle-shaped can containers, which are made of metal and employ a method of screwing a cap into a bottle mouth, like PET bottles, have been distributed.

[0005] By the way, a sealing technique for sealing a can by laser welding for a metal can is disclosed (for example, see Patent Documents 1 to 3).

[0006] Patent Literature l: WO02Z42196 A2 Publication

Patent Document 2: Japanese Patent Laid-Open No. 63-194885

Patent Document 3: Japanese Patent Application Laid-Open No. 61-289932

Disclosure of the invention

Problems to be solved by the invention

[0007] When attempting to seal a sealed container such as a beverage 'food container, such as laser welding, by heat melting, the liquid in the surrounding environment (for example, water applied to the device) and the contents at the time of sealing are fused. In many cases, it is necessary to fuse it with the surface to be squeezed. At this time, the fusion condition changes. After such a change in fusing conditions, the wide range of appropriate conditions is expressed as high suitability for contaminants. And, when trying to seal by laser welding, the fusing conditions that can obtain the suitability of contaminants have not been known so far. In addition, there is no knowledge of how the container structure, in particular the mouth and lid structure, should be used to increase the suitability of contaminants.

[0008] For example, when the PET bottle is sealed by laser welding, the inventor irradiates a general laser spot, and when heating and melting are started at the fusion start point, impurities on the fusion surface are melted. It was found that the force at the fusion start point on the landing surface moves toward the direction of force. As a result, if the laser irradiation is performed once to complete the fusion, a remarkable deviation occurs in the fusion area, which adversely affects the sealing performance and the bonding strength between the container body and the lid. Also, the foreign substance moves so as to be pushed out from the fusion surface by the pressure generated by heating and fusion. As a result, it is possible to discharge the contaminants substantially completely. However, since the contaminants deprive the fusion surface of a certain amount of heat, it is necessary to adjust the laser output. It becomes.

[0009] Accordingly, the object of the present invention is to provide a beverage that is sealed by heat melting, such as laser welding. • For sealed containers such as food containers, the structure of the mouth and lid is devised to improve the suitability of contaminants. It is to give. The purpose is to increase the sealing performance and the bonding strength between the container body and the lid.

Means for solving the problem

[0010] The present inventor diligently studied the above problems, and (1) fixing the portion to be fused so that the foreign substance does not move to another fusion portion during fusion, and (2) fusion. It is necessary to form the structure of the part to be fused so that the foreign substance can move to other than the fusion part during wearing, and (3) to perform laser irradiation taking into account the amount of heat carried out by the foreign substance. We found a container with a mouth and lid structure reflecting these, and found an appropriate laser irradiation method. That is, the sealed container according to the present invention pressurizes the container body with a container body having a mouth, and a stress that causes distortion when the mouth is closed and relaxes the strain. Causing a close contact of the state, And it has the lid | cover formed with the plastic material which this close_contact | adherence part becomes a seal, The said close_contact | adherence part is heat-sealed, It is characterized by the above-mentioned. When the lid is attached to the container body, the intimate part abuts in a pressurized state so that no foreign matter enters the intimate part.

In the sealed container according to the present invention, an annular rib is provided on the outer wall of the mouth portion in parallel with the edge of the round portion, and an annular ring is formed on the edge of the lid to form the close contact portion with the rib. An annular protrusion or recess is provided on the edge side of the mouth portion of the outer wall of the mouth portion from the rib, and the interval between the inner wall of the lid and the ring provided on the edge of the lid is An annular recess or protrusion is provided at a location that is slightly longer than the interval between the annular protrusion or recess provided in the portion and the rib, and the adhesive portion between the rib and the ring is heat-sealed. The case where it is done is included. It is one form of a sealed container. In the case of this container, since the close contact portion can be seen without being blocked by the upward force of the container, it can be fused by irradiating the laser downward from above. Therefore, the laser irradiation apparatus can be simplified.

[0012] In the sealed container according to the present invention, a contact surface between the inner wall surface of the lid and the edge of the mouth portion is provided, and an annular protrusion or recess is formed on the outer wall of the mouth portion in parallel with the edge of the bottom portion. A portion of the inner wall of the lid where the distance from the contact surface is slightly shorter than the distance between the edge of the mouth and the annular protrusion or recess provided in the mouth In addition, an annular recess or protrusion is provided, and a close contact portion between the annular protrusion or recess provided on the outer wall of the mouth and the annular recess or protrusion provided on the inner wall of the lid is heat-sealed. Is included. It is one form of a sealed container.

[0013] In the sealed container according to the present invention, the lid may have a curved portion that sandwiches the front and back surfaces of the edge of the mouth, and the close contact portion between the curved portion and the container body may be heat-sealed. Is included. It is one form of a sealed container.

In the sealed container according to the present invention, it is preferable that a contact surface between the inner wall surface of the lid and the edge of the mouth portion is provided, and the contact surface is heat-sealed. The fusion strength of the lid can be improved.

[0015] In the sealed container according to the present invention, after opening, when the lid is attached again to the mouth of the container body, the container body and the lid are tightly sealed at the contact portion so that the contents do not leak. I like to wear and wear. Resealability of the container can be obtained.

[0016] In the sealed container according to the present invention, a distance between the heat-sealed close-contact portion and the edge of the lid is 10 mm or less, an inner wall surface adjacent to the edge of the lid, and the container body It is preferable that the outer wall is separated. It is possible to discharge the liquid that wets the area around the contact area during fusing.

[0017] In the sealed container according to the present invention, it is preferable that the lid and the container body are formed of plastic resin.

[0018] In the sealed container according to the present invention, it is preferable that the contact portion is heat-sealed by a laser welding method. The boundary between the fused part and the non-fused part is clear, and high-precision fusion is possible.

[0019] In the sealed container according to the present invention, the contact portion is formed of a material that absorbs laser light, or a coating that absorbs laser light is applied to the contact portion, or It is preferable that an object made of a material that absorbs laser light is disposed in the close contact portion! Low energy density! / Can be fused with laser light

[0020] In the sealed container according to the present invention, it is preferable that the lid and the container body are formed of polyethylene terephthalate resin when heat-sealed by a laser welding method. The invention's effect

[0021] The sealed container of the present invention has high suitability for foreign substances by devising the structure of the mouth and the lid. As a result, heat sealing such as a laser welding method can increase the sealing performance and increase the bonding strength between the container body and the lid.

Brief Description of Drawings

FIG. 1 is a schematic view of a sealed container according to a first embodiment, (a) is a schematic longitudinal sectional view of the vicinity of the mouth when the mouth is attached to the container body, and (b) is A (C) is a perspective overview of the lid as seen from the B direction.

FIG. 2 shows a schematic view of a sealed container according to a second embodiment.

FIG. 3 shows a schematic view of a sealed container according to a third embodiment.

FIG. 4 shows a schematic view of a sealed container according to a fourth embodiment. FIG. 5 is a process diagram showing an embodiment of a method for manufacturing a sealed container according to the present embodiment.

100, 200, 300, 400, sealed container

I, 61, container body

2, 16, 18, annular protrusion

3, 62, lid

4, adhesion part

5, 7, edge

6, ribs

8, annular ring

9, mouth

10, annular second protrusion

I I, 15, 17, annular recess

12. An annular second recess

13, the inner wall of the lid

14, Hook

19, contact surface

20, curved part

21, remote part

23, the force to press the rib

24, the force with which the inner wall of the lid presses the edge

25, the force that the curved part pinches the front and back of the edge

26, knob

3a, cover transport means

3b, lid supply means

4, Lid arrangement means

5. Laser generation means

6, close contact 70, Means for rejecting defective containers

BEST MODE FOR CARRYING OUT THE INVENTION

Hereinafter, the present invention will be described in detail with reference to embodiments, but the present invention should not be construed as being limited to these descriptions. First, the sealed container according to the present embodiment will be described with reference to FIGS. In addition, the same code | symbol was attached | subjected to the same member << the same site | part.

[0025] The sealed container according to the present embodiment has a container body having a mouth portion, and a self-strain is generated when the mouth portion is closed, and the container body is pressurized by a stress that relaxes the strain. And a lid formed of a plastic material that forms a tight seal, and the tight seal is heat-sealed. For example

The lid is cylindrical with a top surface, the mouth of the container body is cylindrical, and the lid is attached so that the mouth covers the mouth. At this time, the lid may be a built-in lid or a screw-on lid. The close contact portion between the container body and the lid is always brought into contact in a pressurized state. And this close contact part is used as a seal. According to the above configuration, not only the contents do not spill, but also impurities such as the contents and water splash can be excluded from the contact surface that is the contact portion. Therefore, when the close contact portion is heat-sealed, there is no foreign matter on the close contact surface, so that a phenomenon that adversely affects the heat fusion such as vaporization of the foreign matter or deprivation of heat by the laser hardly occurs. However, in order to keep the contacted part always in a pressurized state, in the sealed container according to this embodiment, when the lid is formed of a plastic material and the mouth is closed with the lid, the lid itself is distorted. In addition, the stress that relaxes the strain is used as a force for pressurization. Hereinafter, several embodiments of a sealed container that realizes this action will be described as examples. Of course, the present invention should not be construed as being limited to these embodiments.

[0026] (First embodiment)

FIG. 1 shows a schematic view of a sealed container according to the first embodiment. (A) is a schematic vertical cross-sectional view of the vicinity of the mouth when the mouth is attached to the container body, (b) is an external appearance view that also shows the A direction force, and (c) is a perspective overview of the lid as seen from the B direction. FIG. In the sealed container 100 according to the first embodiment, an annular rib 6 is provided on the outer wall of the mouth portion 9 of the container body 1 in parallel with the edge 5 of the mouth portion 9, and the rib 6 and the close contact portion are provided on the edge 7 of the lid 3. An annular ring 8 forming 4 is provided, and an annular protrusion 2 is provided on the outer edge 5 of the mouth 9 on the edge 5 side of the mouth from the rib 6, and an edge 7 of the lid 3 is provided on the inner wall of the lid 3. With the ring 8 An annular recess 11 is provided at a location where the interval is slightly longer than the interval between the annular protrusion 2 provided on the mouth 9 and the rib 6. The close contact portion 4 between the rib 6 and the ring 8 is heat-sealed.

[0027] In the sealed container 100, the inner diameter of the lid 3 is designed so that the side wall of the mouth portion 9 is somewhat tightened from the surroundings when the lid 3 is attached. Here, the gap between the annular recess 11 and the ring 8 is formed to be slightly longer than the gap between the annular protrusion 2 provided on the mouth 9 and the rib 6. Therefore, the portion of the lid 3 sandwiched between the annular recess 11 and the ring 8 is distorted in the vertical direction as shown in FIG. . Since the lid 3 is made of a plastic material, a force for pushing the ring 8 downward, that is, a force 23 for pushing the rib 6 is generated in order to alleviate the compression strain. As a result, the adhesive portion 4 is brought into a pressurized state.

[0028] The lid 3 is formed of a plastic material. Specifically, the lid 3 is formed of plastic resin, metal, or a composite material thereof. The metal is, for example, aluminum, iron, or an alloy containing these as a main component. Examples of plastic resins include polyethylene terephthalate resin (PET), glycol-modified polyethylene terephthalate resin (PETG), polybutylene terephthalate resin, polyethylene naphthalate resin, polyethylene resin, polypropylene resin (PP), and cycloolefin. Copolymer resin (COC, cyclic olefin copolymer), ionomer resin, poly 4-methylpentene 1 resin, polymethyl methacrylate resin, polystyrene resin, ethylene-vinyl alcohol copolymer resin, acrylonitrile resin , Poly salt vinyl resin, Poly salt vinylidene resin, Polyamide resin, Polyamide imide resin, Polyacetal resin, Polycarbonate resin, Polysulfone resin, or 4-Fluorinated styrene resin, Atari mouth nitrile —Styrene resin, acrylonitrile— Tajien - is a styrene 榭脂. Of these, PET is particularly preferred. PET has a proven record as a material for beverages and food containers, and when it is fused by laser welding, it has no absorbency for laser, so the close contact surface has absorbability for laser light. By coloring, the area around the contact surface can be heated directly.

[0029] The container body 1 is formed of plastic resin, glass, ceramics, metal, or a composite material thereof. The shape is preferably a bottle shape. The container is sealed by heat sealing. In order to perform sealing, it is not necessary to make the lid thicker than the container body. By forming the container body 1 and the lid 3 with plastic resin, it is possible to join them with a small amount of energy.

In the sealed container 100, an annular second protrusion 10 is provided above the protrusion 2 in the outer wall of the mouth portion 9, and a second recess 12 is provided on the inner wall of the lid 3. Here, the lid 3 is formed so that the distance between the inner wall portion 13 of the lid 3 in contact with the edge 5 and the second recess 12 is slightly shorter than the distance between the edge 5 and the second protrusion 10. Yes. As a result, a contact surface between the edge 5 and the inner wall portion 13 is formed, and the contact surface is always in a pressurized state. Therefore, the foreign matter is also removed from the contact surface, and the adverse effect due to the foreign matter is eliminated, so that heat fusion is facilitated. In addition, the adhesive strength between the container body 1 and the lid 3 is improved.

[0031] Further, in the sealed container 100, a knob 26 is provided to improve the opening of the lid 3. Further, a hooking portion 14 for the rib 6 is provided so that the lid 3 does not fly due to internal pressure applied to the container. Even if the lid 3 is opened carelessly, the hook 14 prevents the lid 3 from popping out.

[0032] (Second Embodiment)

FIG. 2 shows a schematic view of a sealed container according to the second embodiment. A schematic longitudinal sectional view of the vicinity of the mouth when the mouth is attached to the container body is shown. In the sealed container 200 according to the second embodiment, an annular rib 6 is provided on the outer wall of the mouth portion 9 of the container body 1 in parallel with the edge 5 of the mouth portion, and the rib 6 and the close contact portion 4 are formed on the edge 7 of the lid 3. An annular ring 8 is provided, an annular recess 15 is provided on the outer wall of the mouth 9 on the edge 5 side of the mouth 9 from the rib 6, and a ring provided on the edge 7 of the lid 3 of the inner wall of the lid 3. An annular protrusion 16 is provided at a location where the distance from 8 is slightly longer than the distance between the annular recess 15 provided in the mouth 9 and the rib 6. The close contact portion 4 between the rib 6 and the ring 8 is heat-sealed. The difference between the second embodiment and the first embodiment is that the relationship between protrusions and depressions is reversed.

[0033] In the sealed container 200, the inner diameter of the lid 3 is designed so that the side wall of the mouth portion 9 is somewhat tightened from the surroundings when the lid 3 is mounted. Here, the lid 3 is formed so that the interval between the annular protrusion 16 and the ring 8 is slightly longer than the interval between the annular recess 15 and the rib 6. Therefore, in the portion of the lid 3 sandwiched between the annular protrusion 16 and the ring 8, the lid 3 is tightened. The force causes strain in the vertical direction as seen in Fig. 2, resulting in compressive stress. Since the lid 3 is made of a plastic material, a force 23 that pushes the ring 8 downward, that is, a force 23 that pushes the rib 6 is generated to alleviate this compression strain. As a result, the contact portion 4 is brought into a pressurized state.

[0034] The materials of the lid 3 and the container body are the same as in the first embodiment. Also in the sealed container of the second embodiment, a contact surface between the inner wall surface of the lid 3 and the edge 5 of the mouth portion 9 may be provided (not shown), and the contact surface may be heat-sealed. Further, a knob (not shown) and a hooking part (not shown) may be provided.

[0035] (Third embodiment)

FIG. 3 shows a schematic view of a sealed container according to the third embodiment. A schematic longitudinal sectional view of the vicinity of the mouth when the mouth is attached to the container body is shown. In the sealed container 300 according to the third embodiment, a contact surface 19 between the inner wall surface of the lid 3 and the edge 5 of the mouth portion 9 is provided, and an annular recess is formed on the outer wall of the mouth portion 9 in parallel with the edge 5 of the mouth portion 9. 17 is provided. An annular protrusion 18 is provided on the inner wall surface of the lid 3. Further, in the inner wall of the lid 3, the space between the contact surface 19 is slightly shorter than the space between the edge 5 of the mouth 9 and the annular recess 17 provided in the mouth 9. An annular protrusion 18 is provided. The close contact portion 4 between the annular recess 17 provided on the outer wall of the container body 1 and the annular protrusion 18 provided on the inner wall of the lid 3 is heat-sealed.

[0036] In the third embodiment, similar to the relationship between the second embodiment and the first embodiment, the relationship between the protrusion and the recess may be reversed as a similar form of the third embodiment (not shown). .

[0037] In the sealed container 300, the inner diameter of the lid 3 is designed so that the side wall of the mouth portion 9 is somewhat tightened from the periphery when the lid 3 is mounted. Here, the distance between the abutment surface 19 and the annular protrusion 18 provided on the lid 3 is a force slightly shorter than the distance between the edge 5 of the mouth 9 and the annular recess 17 provided on the mouth 9. Thus, a lid 3 is formed. Therefore, in the portion of the lid 3 between the contact surface 19 and the annular protrusion 18, the tightening force of the lid 3 causes a strain in the vertical direction as seen in FIG. . Since the lid 3 is made of a plastic material, the inner wall surface of the lid 3 generates a force 24 pressing the edge 5 in order to relieve the tensile strain, and the edge 5 comes into contact with the inner wall surface of the lid 3. On the other hand, the annular protrusion 18 of the lid 3 and the annular recess 17 of the container body 1 are brought into close contact with each other, and the contact portion 4 is brought into a pressurized state. [0038] The materials of the lid 3 and the container body 1 are the same as those in the first embodiment. Also in the sealed container of the third embodiment, the contact surface 19 may be heat-sealed. Further, a knob (not shown) and a hooking part (not shown) may be provided.

[0039] (Fourth embodiment)

FIG. 4 shows a schematic view of a sealed container according to the fourth embodiment. A schematic longitudinal sectional view of the vicinity of the mouth when the mouth is attached to the container body is shown. In the sealed container 400 according to the fourth embodiment, the lid 3 has the curved portion 20 that sandwiches the front and back surfaces of the edge 5 of the mouth portion 9 of the container body 1, and the close contact portion 4 between the curved portion 20 and the container body 1 is heated. It is fused.

[0040] In the sealed container 400, distortion occurs when the curved portion 20 sandwiches the front and back surfaces of the edge 5, and in order to alleviate this strain, the contact portion 4 between the curved portion 20 and the container body 1 is pressurized. ing. Reference numeral 25 in FIG. 4 indicates the force with which the curved portion 20 sandwiches the front and back surfaces of the edge 5.

[0041] The materials of the lid 3 and the container body 1 are the same as those in the first embodiment. Also in the sealed container of the fourth embodiment, a knob (not shown) and a hooking part (not shown) may be provided.

[0042] In the sealed containers of the first to fourth embodiments, when the lid 3 is mounted again on the mouth 9 of the container body 1 after opening, the container body 1 and the container body 1 are connected so that the contents do not leak. It is preferable that the lid 3 is in close contact with each other. Resealability of the container can be obtained. In the embodiment, the contact portion 4 is in a pressurized state. By adjusting the thickness of the lid 3 and the size relationship between the inner diameter of the lid 3 and the outer shape of the mouth 9 in order to make the pressurized state an appropriate pressure, the contents can be prevented from leaking.

[0043] In the sealed containers of the first to fourth embodiments, the distance between the heat-sealed contact portion 4 and the edge 7 of the lid 3 is 10 mm or less, and the inner space adjacent to the edge 7 of the lid 3 is The wall surface is preferably separated from the outer wall surface of the container body 1. For example, FIG. 2 shows a partially enlarged view of C. The distance X between the contact portion 4 and the edge 7 of the lid 3 is 10 mm or less, and a separation portion 21 between the inner wall surface of the lid 3 and the outer wall surface of the container body 1 is provided. In other embodiments, the distance X and the separation portion 21 may be provided similarly. With this structure, the liquid that wets the periphery of the contact portion 4 can be discharged during the fusion.

[0044] In the sealed containers of the first to fourth embodiments, the close contact portion 4 is preferably heat-sealed by a laser welding method. Compared with the case where the heat source is used as the heat source, the fused part The boundary between the minute portion and the non-fused portion is clear, and high-precision fusion is possible.

[0045] In the sealed containers of the first to fourth embodiments, the close contact portion 4 is formed of a material that absorbs laser light, or is paint applied to the close contact portion 4 that absorbs laser light, Alternatively, an object having a material force that absorbs laser light may be disposed in the contact portion 4. When fusing by the laser welding method, even if the object to be fused is not absorbed by the laser welding method, the vicinity of the adhesion surface can be directly heated by coloring the adhesion surface of the adhesion portion with absorption to the laser beam. In order to form the close contact portion with a material that absorbs laser light, for example, a plastic trunk is added with a dye or pigment to form a container body and / or a lid. In order to apply the adhesion portion 4 with a paint that absorbs laser light, for example, the paint is printed by various printing methods. Examples of the material that absorbs the laser beam disposed in the close contact portion 4 include a material that is the same as the container body or the lid, and that is applied with a paint or contains a dye or a pigment. By providing an absorption portion for laser light in this way, the laser absorption rate is increased, and laser welding can be performed with a small amount of energy. The dye or pigment is, for example, a metal material, a ceramic, or an organic pigment, and absorbs laser light. It is preferable to adjust the wavelength of the laser beam, the laser power, and the laser scanning speed according to the degree of absorption of the absorber with respect to the laser beam.

Next, a sealing method for the sealed container according to the present embodiment will be described with reference to FIG. FIG. 5 is a process diagram showing an embodiment of a method for manufacturing a sealed container according to this embodiment. In step S1, the container body 61 filled with the contents is introduced into the laser welding machine by a conveying means such as a conveyor (not shown). At this time, if the contents are foamed, bubbles are removed and carbon dioxide purge or nitrogen gas purge is performed.

[0047] Next, in step S2, the lid 62 is transported to the lid supply means 63b by the lid transport means 63a. The lid supply means 63b supplies one lid 62 to one container body 61 to the mouth.

[0048] Next, in step S3, the lid arranging means 64 attaches the lid 62 to the mouth of the container body 61. As a result, the contact surface is brought into a pressurized state at the contact portion between the lid and the container body.

[0049] Next, in step S4, the laser generator 65 causes the container body 61 and the lid 62 to move. Irradiate the contact 66 with a laser. Here, the entire contact portion 66 can be fused while rotating the container 61 around the central axis by irradiating the laser in a spot shape or a line shape (one rotation means of the container 61 is not shown). .

[0050] During laser irradiation, the laser intensity is preferably monitored by monitoring the laser output. The laser irradiation position is preferably monitored by monitoring light emission or heat generation with a temperature sensor such as a light sensitive sensor or an infrared sensor. It is preferred that plastic welding be monitored by monitoring light emission or heat generation with a light sensitive sensor or a temperature sensor. You can also use an image sensor such as a CCD.

[0051] Examples of the laser oscillating element inserted into the laser generating means 65 include gas lasers such as semiconductor lasers and carbon dioxide gas lasers, and YAG lasers. The material of the container body and lid for laser welding, the laser It is appropriately selected according to various parameters such as irradiation movement speed and irradiation spot shape. The wavelength of the laser beam is, for example, 800—lOOOnm. When laser welding plastic containers or bottle-shaped can containers, semiconductor lasers are preferred. It is preferable that the energy density of the laser light applied to the contact portion is, for example, 150 J per fusion area lcm ² . The fusion can be terminated without causing thermal deformation.

Here, in order to increase the absorptance of the laser beam, it is preferable to provide a step of providing a laser beam absorber in the close contact portion. Laser welding can be performed with high precision even for contours and undulations that make the mechanical contact complicated along the absorber. This is because the laser beam can narrow the irradiation spot and the place where the absorber is provided is mainly welded. This step may be provided before step S1, any time before laser irradiation, between step S1, step S2 or step S3. This process is not essential because it is effective when welding materials that do not have an absorption band for laser light. In other words, laser welding can be performed only by irradiating the laser when the joint part absorbs laser light as in some color bottles.

[0053] Next, in step S5, the poorly sealed container 70 removes the poorly sealed container. Judgment of poor sealing is based on the above monitoring result and image inspection machine It is preferable to do it based on the appearance inspection results.

In the conventional metal can clamping process, it is difficult to determine whether or not the container is properly sealed at the time when the clamping process is actually performed. For this reason, if a sealing failure occurs in the tightening process even though the inspection results before the start of production are good, the failure will be discovered after a considerable amount of time has passed since the actual failure. In such a case, the number of containers that need to be discarded and the downtime of the production equipment become extremely large. On the other hand, according to the sealed container manufacturing method according to the present embodiment, whether or not the welding process is properly performed can be detected in a very short time, and thus does not suffer from the above disadvantages in the metal can clamping process. .

In the present invention, the following welding method can be applied instead of the laser welding method. That is, the tightly sealed portion is fused by an impulse sealing method, a high frequency welding method, a vibration welding method, a spin welding method, an ultrasonic welding method, a hot air welding method, or a heat sealing method to produce a sealed container. .

[0056] The impulse sealing method is a method in which a strong current is rapidly passed through a ribbon heater to heat and weld the close contact portion. The high-frequency welding method is a welding method by internal heating in which high-frequency current is absorbed by a close contact portion having a large dielectric constant and dielectric loss tangent. Use a film with a large dielectric constant and dielectric loss tangent. The vibration welding method is a welding method in which a close contact portion is rubbed instead of spin to generate heat and melt adhesion. The spin welding method is a method in which the close contact portions are rotated and bonded together and melt welded by frictional heat. The ultrasonic welding method is a method in which ultrasonic vibration energy is applied to melt-bond the close contact portions. The hot-air welding method is a method in which air or gas is sent to a heated heater and sprayed to the close contact portion. The heat seal method is a method in which welding is performed by heating under pressure with a close contact portion sandwiched between heating plates. Each welding method can be selected appropriately according to the shape of the container.

Claims

The scope of the claims

[1] a container body having a mouth;

When the mouth is closed, the self is distorted, and a stress that relaxes the strain causes a close contact portion in a pressurized state with respect to the container body, and the close contact portion is sealed and sealed. And having a lid formed of a plastic material,

The sealed container, wherein the contact portion is heat-sealed.

[2] An annular rib is provided on the outer wall of the mouth portion in parallel with the edge of the round portion,

An annular ring is formed on the edge of the lid to form a close contact portion with the rib,

Of the outer wall of the mouth, an annular protrusion or depression is provided on the edge side of the mouth from the rib,

Of the inner wall of the lid, the spacing force with the ring provided at the edge of the lid, at a location that is slightly longer than the spacing between the annular protrusion or recess provided at the mouth and the rib, An annular recess or protrusion is provided,

The sealed container according to claim 1, wherein a close contact portion between the rib and the ring is heat-sealed.

[3] Provide a contact surface between the inner wall surface of the lid and the edge of the mouth,

An annular protrusion or depression is provided on the outer wall of the mouth portion in parallel with the edge of the bottom portion, and an interval between the inner wall of the lid and the contact surface is provided on the edge of the mouth portion and the mouth portion. An annular recess or protrusion is provided at a location slightly shorter than the interval between the annular protrusion or recess,

The contact portion between the annular protrusion or recess provided on the outer wall of the mouth and the annular recess or protrusion provided on the inner wall of the lid is heat-sealed. Sealed container.

4. The lid according to claim 1, wherein the lid has a curved portion sandwiching the front and back surfaces of the edge of the mouth portion, and a close contact portion between the curved portion and the container body is heat-sealed. Sealed container.

[5] Provide a contact surface between the inner wall surface of the lid and the edge of the mouth,

The sealed valley device according to claim 1, 2, 3, or 4, wherein the contact surface is heat-sealed.

[6] The container body and the lid are in close contact with each other at the contact portion to the extent that the contents do not leak when the lid is attached again to the mouth of the container body after opening. The sealed container according to claim 1, 2, 3, 4 or 5.

[7] The distance between the heat-sealed portion and the edge of the lid is 10 mm or less, and the inner wall surface adjacent to the edge of the lid is separated from the outer wall surface of the container body. The sealed container according to claim 1, 2, 3, 4, 5 or 6.

8. The sealed container according to claim 1, 2, 3, 4, 5, 6 or 7, wherein the lid and the container body are formed of plastic resin.

[9] The close contact portion is heat-sealed by a laser welding method.

Sealed container according to 1, 2, 3, 4, 5, 6, 7 or 8.

[10] The contact portion is formed of a material that absorbs laser light, or a force that a coating that absorbs laser light is applied to the adhesion portion, or laser light is absorbed by the contact portion. 2. An object of material force is arranged.

2, 3, 4, 5, 6, 7, 8 or 9 sealed container.

11. The sealed container according to claim 9, wherein the lid and the container body are formed of polyethylene terephthalate resin.