JP2007039117A - Resealable airtight container - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an inexpensive, transparent, resealable and set-in type airtight container which is provided with a satisfactory recycling characteristic, does not require chemical modification, is not easily broken and does not easily leak. <P>SOLUTION: This airtight container having a resealing characteristic is provided with a container body 1 having a tubular opening 3 and with a cover 2 tubularly formed having a top face for closing the opening being outwardly fitted on the opening. The body made of polyethylene terephthalate resin is structured to control the deformation of the opening by limiting the deformation of the body in the body when a stress is applied to the body. The opening is provided with one continuous annular protrusion 6 along its peripheral direction on an outer tube wall. The cover made of amorphous polyethylene terephthalate resin having a density of 1.320-1.340 g/cm<SP>3</SP>and a thickness of ≥80 μm and <390 μm is provided with one continuous annular recess 7 along its peripheral direction on an inner tube wall to be fitted on the annular protrusion. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention seals a container body made of polyethylene terephthalate (hereinafter referred to as PET) resin, which contains contents such as food and beverages, with a lid made of PET resin having excellent recyclability and transparency. The present invention relates to a sealed container having resealability. Here, resealability means that the container does not leak at least when it is used in a situation where the container is loaded, such as when the container is held by hand or transported in a bag, etc. It refers to a characteristic that can be obtained.

  Various types of containers such as bottles, cans, and plastic containers are known as sealed containers, for example, beverage containers. In recent years, plastic containers, particularly PET resin containers (PET bottles) have been widely used from the viewpoint of convenience such as good handling properties.

  In order to recycle the container, the lid of the PET bottle is preferably formed of the same material, the PET resin. However, since a lid made of PET resin is easy to break and it is difficult to ensure sealing performance (see, for example, Patent Document 1), polypropylene resin is mainly used, and polyethylene and other materials such as polyethylene are rich in flexibility and extensibility. A plastic material is used as a material for the lid (see, for example, Patent Document 2).

  In order to use the PET resin for the lid, a significant chemical modification of the PET resin such as a copolymer with polyethylene is required (see, for example, Patent Document 3).

  In PET bottles, a method of screwing a lid into the bottle mouth is used as a sealing method (see, for example, Patent Document 1).

Japanese Patent Laid-Open No. 10-139061 JP 2002-348326 A JP 2002-302133 A

  However, when the lid is made of polypropylene resin, including the technique disclosed in Patent Document 2, in order to recycle, the container body and the lid must be separated, which is troublesome. Moreover, transparency is inferior compared with a container main body.

  Further, when the lid is formed by modifying the PET resin as in the technique disclosed in Patent Document 3, the cost associated with the modification increases, and the recyclability may be insufficient.

  Furthermore, since the screw-type lid including the lid disclosed in Patent Document 1 has a large thickness and rigidity, the lid is a significant cost increase factor in the entire container.

  Therefore, an object of the present invention is to use an embedded PET resin lid that can be resealed with good recyclability, transparency, low cost, no chemical modification, hardly cracking and leaking. To provide a sealed container.

The present inventors diligently studied the above problems. (1) The container body is formed of a hard PET resin, the lid is formed of a soft PET resin, and the sealing method is not a screw-in type but a screw-in type. The present inventors have found that the problems can be solved and completed the present invention. Specifically, the sealed container having resealability according to the present invention is formed in a container body having a cylindrical mouth portion and a cylindrical shape with a top surface, and is fitted into the mouth portion from the outside of the mouth portion. In the sealed container having resealability with a lid for sealing the container body, the container body is configured such that deformation of the body portion is limited to the inside of the body portion when stress is applied to the body portion. The structure has a structure in which deformation is suppressed, and is formed of a polyethylene terephthalate resin. The mouth portion has an annular convex portion connected to the outer wall of the cylinder along the circumferential direction. The lid has an inner wall of the cylinder. And formed of an amorphous polyethylene terephthalate resin having a density of 1.320 to 1.340 g / cm ³ , and having a continuous annular recess for fitting the annular protrusion along the circumferential direction. Thickness is 80μm or more 3 And less than 0 .mu.m.

  In the sealed container having resealability according to the present invention, the lid is preferably formed by a compressed air method or a vacuum method. A lid formed by a compressed air method or a vacuum method has a small thickness and is inexpensive.

  In the sealed container having resealability according to the present invention, the container body is preferably formed by blow molding or injection molding. By forming by blow molding or injection molding, it is easy to obtain a structure in which the deformation of the mouth is suppressed.

  In the sealed container having resealability according to the present invention, it is preferable that the lid has an adhesive force of 9.8 N or more measured by pulling the top surface of the lid upward and measuring the lid until the lid is opened. It becomes difficult to pop out the contents, and sufficient sealing performance is easily obtained when the lid is opened again with the opened lid.

  In the sealed container having resealability according to the present invention, the structure in which the deformation of the mouth portion is suppressed is such that the container body has a gripping portion having a maximum or substantially maximum body diameter at a portion 30 mm or more away from the mouth portion. And a structure having a shoulder portion between the trunk portion and the mouth portion. By providing the grip portion, it becomes easy to apply stress only to the body portion which is the grip portion, and even if the body portion is deformed by the stress, the transmission of the deformation is cut off by providing the shoulder portion. As a result, the deformation of the mouth can be prevented, and as a result, the contents are difficult to leak.

  In the sealed container having resealability according to the present invention, it is preferable that the shoulder portion has a shape in which a ratio of diameter reduction from the trunk portion to the mouth portion is changed. Even if the amount of deformation of the body, which is the gripping portion, is large, transmission of the deformation can be blocked by the shoulder, and deformation of the mouth can be prevented.

  In the sealed container having resealability according to the present invention, is the structure in which the deformation of the mouth portion is suppressed, at least the shoulder portion being a structure formed with a thicker wall than the trunk portion? Or at least the shoulder is crystallized, or the outer wall of the mouth or the shoulder is provided with a rib-like reinforcement ring along the circumferential direction, or A combination of these structures is preferred. Even if the stress applied to the trunk portion is large, since the rigidity of the shoulder portion itself is enhanced by the above structure, the deformation of the mouth portion can be prevented.

  In the sealed container having resealability according to the present invention, the container body is formed in a cup shape, and the structure in which the deformation of the mouth portion is suppressed is such that at least a portion lower than the mouth portion is the body body. It is a structure formed with a thick wall compared to the part, or a structure in which at least the lower part is crystallized from the mouth part, or from the mouth part or the mouth part Also, it is preferable that a rib-shaped reinforcing ring is provided along the circumferential direction on the outer wall of the lower portion, or a combination of these structures. When the container body is formed in a cup shape, the deformation of the body part is easily transmitted to the mouth part when stress is applied to the body part. However, by adopting any one of the above-described structures in which the deformation of the mouth portion is suppressed, even if the container body is formed in a cup shape, the deformation of the body portion is hardly transmitted to the mouth portion.

In the sealed container having resealability according to the present invention, the deformation rate calculated by (Equation 1) in the caliber direction of the mouth part when the trunk part is crushed by 10% in the trunk diameter direction is 0.50% or less. It is preferable that By providing a structure in which the deformation of the mouth portion is suppressed such that the deformation rate is 0.50% or less, the sealing performance of the lid can be secured, and leakage of the contents can be almost eliminated.
(Equation 1) Deformation rate (%) = {(minimum diameter when unloaded−minimum diameter when deformed) / minimum diameter when unloaded} × 100

  In the sealed container having resealability according to the present invention, when a predetermined load is applied to the outer peripheral portion of the region where the lid and the mouth overlap, the amount of deformation of the mouth is smaller than the amount of deformation of the lid. preferable. By making the mouth portion harder than the lid, the sealing performance of the lid can be secured, and leakage of the contents can be almost eliminated.

  In the sealed container having resealability according to the present invention, a rib-like neck ring is further provided on the barrel side of the tubular outer wall of the mouth portion than the annular convex portion, and the tubular end portion of the lid faces outward. It is preferable that a flange is provided and the neck ring and the flange are fused. Even if the contents are, for example, carbonated drinks, it is possible to prevent the lid from popping out. Moreover, the presence or absence of opening can be confirmed.

  In the sealed container having resealability according to the present invention, a knob is provided on the lid, and a rib-like neck ring with a notch is provided on the barrel side of the tubular outer wall of the mouth portion relative to the annular convex portion. And it is preferable to provide a mechanism for preventing the lid from popping out by hooking the knob on the notch. Even if the contents are, for example, carbonated drinks, it is possible to prevent the lid from popping out.

  The sealed container having resealability according to the present invention preferably includes a shrink film cover that covers the mouth and the lid that seals the mouth. The lid can be prevented from popping out until it reaches the consumer. Moreover, the presence or absence of opening can be confirmed.

  In the sealed container having resealability according to the present invention, a gas barrier thin film is preferably formed on the surface of at least one of the container body and the lid. By improving the gas barrier properties of the container, the expiration date or expiration date can be extended.

  The sealed container according to the present invention has good recyclability, has transparency, is inexpensive, does not require chemical modification, is difficult to break and leaks, and can be resealed while ensuring sealing properties.

(Function)
In the sealed container having resealability according to the present embodiment, the container body and the lid are both formed of PET resin in order to ensure recyclability. Here, when a screw-in type lid is formed of PET resin by injection molding in order to ensure resealability, chemical sealing of the PET resin is required because the sealing property is insufficient and cracking is likely to occur. Therefore, in order to achieve both sealing performance and prevention of cracking on the premise that a general-purpose PET resin is used, the container body, particularly its mouth, is hardened while the lid is softened. Furthermore, the lid is not a screw-in type but a fitting type. By making the mouth hard, the sealability is prevented from being lost by deformation, and the lid is softened to reduce cracking of the lid. When making the lid soft, it is difficult to use a screw-in type lid, so it was decided to use a built-in type lid. Here, in order to harden the mouth, means for increasing the wall thickness of the mouth can be considered, but there is a limit to the hardness of the mouth that can be increased by this means. Therefore, the container body is provided with a structure that suppresses deformation of the mouth part by limiting the deformation of the body part when the stress is applied to the body part, thereby suppressing the deformation of the mouth part. It was decided.

  Hereinafter, the present invention will be described in detail with reference to embodiments, but the present invention is not construed as being limited to these descriptions. First, a sealed container having resealability 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 and the same site | part.

FIG. 1 shows a schematic view in a longitudinal section of one form of a sealed container having resealability according to the present embodiment. A sealed container 100 shown in FIG. 1 is formed in a cylindrical shape with a container body 1 having a cylindrical mouth portion 3 and a top surface 5, and is a lid that seals the mouth portion 3 by being fitted from the outside of the mouth portion 3. 2, the container body 1 has a structure in which the deformation of the mouth portion 3 is suppressed by the deformation of the body portion 4 being limited to the inside of the body portion 4 when stress is applied to the body portion 4. The mouth 3 has an annular projection 6 connected to the outer wall of the cylinder along the circumferential direction, and the lid 2 has an annular projection of the inner wall of the cylinder along the circumferential direction. It has a continuous annular recess 7 for fitting the portion 6 and is formed of an amorphous polyethylene terephthalate resin having a density of 1.320 to 1.340 g / cm ³ and has a wall thickness of 80 μm or more and less than 390 μm. is there.

  The container body 1 has a so-called bottle shape, and the mouth portion 3 has a cylindrical shape. The cylindrical shape here includes not only a cylindrical shape but also a case where the diameter increases or decreases along the axis X direction. In addition, the cross-sectional shape with respect to the axis X includes not only a circular shape but also an elliptical shape, a rectangular shape, or a polygonal shape. Further, the container body 1 may be formed in a cup shape (for example, FIG. 5), and in this case, the mouth portion 3 has a cylindrical shape.

  The container body 1 is molded using a polyethylene terephthalate resin (PET resin) by a publicly known molding method such as blow molding or injection molding. In the present embodiment, the PET resin includes a modified PET resin such as glycol-modified polyethylene terephthalate (PETG) that can be treated as being equivalent to the PET resin in recycling.

  The contents filled in the container body 1 are mainly various beverages such as beer, sparkling liquor, carbonated beverages and soft drinks, and may be seasonings, edible oils or foods. The sealed container according to the present embodiment has resealability, that is, when it is used in a situation where a load is applied to the container, such as when the container is gripped by hand or transported in a bag, etc. It is suitable for filling the contents that require the property of sealing enough to prevent water leakage. Therefore, it has suitability as a large capacity container of 1 liter or more.

  The mouth portion 3 is provided with an annular convex portion 6 connected to the outer wall of the cylinder along the circumferential direction. In the sealed container 100 having resealability shown in FIG. 1, the case where two annular protrusions 6 a on the tube tip side and an annular protrusion 6 b provided below the annular protrusion 6 are provided is shown. Only one unit 6 may be provided, or three or more units 6 may be provided. As the number of the annular projections 6 increases, the adhesion force of the lid 2 increases, so that it is appropriately determined depending on the required pressure resistance. Further, the number is limited by the tube length of the mouth portion 3.

  The lid 2 is formed in a cylindrical shape with the top surface 5 and seals the mouth 3 by fitting from the outside of the mouth 3. Here, the cylindrical shape has a shape in which the side surface portion of the cylinder of the lid 2 is in contact with the side surface of the mouth portion 3, and thus has substantially the same shape as the side surface of the mouth portion 3. Therefore, it includes not only a cylindrical shape but also a case where the diameter increases or decreases along the axis X direction. In addition, the cross-sectional shape with respect to the axis X includes not only a circular shape but also an elliptical shape, a rectangular shape, or a polygonal shape. The lid 2 is provided with a continuous annular concave portion 7 for fitting the annular convex portion 6 along the circumferential direction on the inner wall of the lid.

The lid 2 is molded using an amorphous polyethylene terephthalate resin having a density of 1.320 to 1.340 g / cm ³ . The lid 2 has translucency, and the contents can be confirmed through the lid 2. Amorphous polyethylene terephthalate resins include those generally referred to as A-PET and PETG. A crystallization inhibitor is contained in the PET resin or polymerized as a part of the structure in the crystal structure of PET. As a result, amorphization is realized. By using this resin to form a wall having a thickness of 80 μm or more and less than 390 μm, preferably 150 to 300 μm, the lid is excellent in flexibility, is not broken, and has good adhesion. Since it has appropriate flexibility, when the lid 2 is mounted on the mouth 3 of the container body 1 again, the deformation of the lid 2 is in the range of plastic deformation, and resealability can be obtained while ensuring sealing performance. . If the lid 2 has a wall thickness of less than 80 μm, it has flexibility but it may be broken if the internal pressure is high, such as in the case of carbonated beverages, while if it is 390 μm or more, the flexibility will be poor. It may break. Moreover, since the amount of resin increases, economic efficiency falls.

The lid 2 is preferably formed by a compressed air method or a vacuum method in order to form a wall thickness of 80 μm or more and less than 390 μm. A lid molded by a compressed air method or a vacuum method can be molded within the above thickness range and is inexpensive. FIG. 2 shows a molding process of the lid 2 using a compressed air method, where (a) shows a sheet heating stage, (b) shows a compressed air forming stage, and (c) shows a demolding stage. For example, a sheet 23 made of an amorphous polyethylene terephthalate resin having a thickness of 80 μm or more and less than 390 μm and a density of 1.320 to 1.340 g / cm ³ is prepared and heated by the heating plate 21 (FIG. 2A). See). Next, the sheet 23 is sandwiched between the mold 22 and the heating plate 21, the compressed air 24 is blown out from the surface of the heating plate 21, and the sheet 23 is pressed against the inner surface of the mold 22 (FIG. 2B). reference.). After the sheet 23 is deformed into the shape of the lid 2, the lid 2 is taken out from the mold 22 (see FIG. 2C). Since a large number of lids 2 can be formed from one sheet 23, the lids 2 are cut one by one and separated (not shown).

  Next, the relationship between the annular convex portion 6 of the container body 1 and the annular concave portion 7 of the lid 2 will be described. As shown in FIG. 1, the shape of the annular convex portion 6 is preferably a semicircular convex portion on the vertical end surface of the container. Alternatively, it may be semi-elliptical. If the surface of the annular convex portion 6 is angular, the opening and closing may not be smooth. In order to improve the sealing performance, the shape of the annular convex portion 6 is preferably in an inverted relationship with the shape of the annular concave portion 7 so that the annular concave portion 7 is fitted. In the sealed container 100 shown in FIG. 1, the annular convex portion 6 a has a reverse relationship with the annular concave portion 7 a, and the annular convex portion 6 b has a reverse relationship with the annular concave portion 7 b. The annular convex portion 6a fits into the annular concave portion 7a, and the annular convex portion 6b fits into the annular concave portion 7b.

  In the sealed container having resealability according to the present embodiment, the top surface of the lid 2 is pulled upward, and the adhesion force of the lid measured until the lid 2 is opened is 9.8 N or more, preferably 20 N or more. It is preferable. The popping out of the contents is reduced, and the opened lid is easy to reseal while ensuring the sealing performance. The close contact force of the lid increases as the height of the annular convex portion 6 and the depth of the annular concave portion 7 correspond to the height, and increases as the surfaces of the annular convex portion 6 and the annular concave portion 7 become angular, The larger the number of sets of the annular convex portion 6 and the annular concave portion 7, the larger the number. In addition, since the force is required for resealing as the contact strength of the lid increases, the contact strength of the lid is preferably 50 N or less.

  To measure the adhesion of the lid, fix the container body of the sealed sealed container, attach a metal jig to the top surface of the lid, pull the metal jig at a speed of 50 mm / min with a tensile tester, The stress at the time when any part of the annular recess 7 is removed from the projection 6 is measured.

  In the sealed container having resealability according to the present embodiment, when a predetermined load is applied to the outer peripheral portion of the region where the lid 2 and the mouth portion 3 overlap, the deformation amount of the mouth portion 3 is smaller than the deformation amount of the lid 2. Is preferred. By making the mouth 3 harder than the lid 2, the sealing performance of the lid 2 can be ensured, and leakage of the contents can be almost eliminated. The hardness of the mouth 3 can be increased by thickening the wall or crystallizing the mouth 3.

  In addition, as shown in FIG. 1, by forming the lid 2 so that the end surface of the tube tip of the mouth 3 and the inner surface of the lid 2 are in close contact when the annular convex portion 6 is fitted into the annular concave portion 7, The sealing property of the contents can be further improved.

  As shown by the sealed container 100 shown in FIG. 1, in the sealed container having resealability according to this embodiment, the hook portion 18 provided at one end of the flange 16 is hooked on the neck ring 14, It is preferable to provide a pop-out mechanism for the lid 2 by hooking and holding the knob 15 provided at the end to the ring 13.

  Next, various forms of the structure in which deformation of the mouth portion 3 is suppressed by restricting deformation of the body portion 4 to the inside of the body portion 4 when stress is applied to the body portion 4 are shown in FIGS. 4 and FIG. 4 will be described specifically.

  3A and 3B are schematic views schematically showing a state of deformation when stress is applied to the sealed container 100 shown in FIG. 1, wherein FIG. 3A is a state before deformation, and FIG. 3B is a state after deformation. showed that. As shown in FIG. 3, the structure in which the deformation of the mouth portion 3 is suppressed is specifically when a stress 10 is applied to any part of the body portion 4 of the container body 1 (FIG. 3 ( a)) Even if the crushed portion 11 occurs in the body portion 4 and deforms, the crushed portion 11 is blocked by the shoulder portion 8 and is not transmitted to the mouth portion 3 (FIG. 3B), and the mouth portion 3 is deformed. It is a structure that does not easily occur.

  In order to make the structure in which the deformation of the mouth part 3 is suppressed, first, as shown in the structure shown in FIG. 1, the container body 1 has a body diameter of 30 mm or more away from the mouth part 3. It is preferable to have a structure having the body part 4 which is the grip part at the maximum or substantially at the maximum and the shoulder part 8 between the body part 4 and the mouth part 3. The container body 1 has a so-called bottle shape, and the mouth 3 and the body 4 are separated from each other. By providing the grip portion, stress is easily applied only to the body portion 4 which is the grip portion. This is because it often hits at the point where the maximum body diameter is reached. Even when the body portion is deformed by stress, the deformation is blocked by providing the shoulder portion 8. As the mouth 3 and the body 4 are further away from each other, the effect of blocking the transmission of deformation is higher. Therefore, the interval between the mouth 3 and the body 4 is preferably 30 mm or more. By adopting this structure, deformation of the mouth 3 can be prevented, and as a result, the contents filled in the container body 1 are hardly leaked.

  FIG. 4 is a schematic view in a longitudinal section of another form of the sealed container having resealability according to the present embodiment, and FIG. 4A is a shoulder 8 in which the ratio of diameter reduction from the body 4 to the mouth 3 is changed. If it has a shape, (b) has a shoulder 8 formed of a thick wall compared to the barrel 4, (c) has a crystallized shoulder 8, (d) The case where a rib-shaped reinforcing ring is provided along the circumferential direction on the outer wall of the mouth 3 or the shoulder 8 is shown. Here, in FIGS. 4A to 4C, the left portion is symmetric with respect to the axis X of the container, and thus the description is omitted. Moreover, in FIG.4 (d), the opening | mouth part 3 when the cover 2 is not mounted | worn was shown.

  As in the sealed container 200 shown in FIG. 4A, the shoulder portion 8 preferably has a shape in which the ratio of diameter reduction from the body portion 4 to the mouth portion 3 is changed. For example, the ratio of the diameter reduction from the body part 4 to the mouth part 3 is initially large, and the shoulder part 8 becomes a shoulder by changing the ratio gradually small. The shoulder 8 of the sealed container 100 is a shoulder because the body 4 and the mouth 3 are smoothly connected, whereas the shoulder 8 of the sealed container 200 is reduced in diameter from the body 4 to the mouth 3. Since it has a shape in which the ratio is changed, even if the amount of deformation of the body portion 4 that is the grip portion is larger, the deformation of the mouth portion 3 can be prevented by blocking the transmission of the deformation by the shoulder portion 8. it can.

  As in the sealed container 300 shown in FIG. 4B, the shoulder portion 8 is preferably formed with a wall that is thicker than the body portion 4. Even if the stress applied to the trunk portion 4 is large, the rigidity of the shoulder portion 8 itself is increased by the above-described structure, so that the deformation of the mouth portion 3 can be prevented.

  As in the sealed container 400 shown in FIG. 4C, it is preferable that at least the shoulder 8 is crystallized. The dots in FIG. 4 (c) indicate that it is crystallized. Even if the stress applied to the trunk portion 4 is large, the rigidity of the shoulder portion 8 itself is increased by the above-described structure, so that the deformation of the mouth portion 3 can be prevented. In the sealed container 400 shown in FIG. 4C, the form in which only the shoulder portion 8 is crystallized is shown. However, even if the body portion 4 or the mouth portion 3 is crystallized to increase the rigidity of the entire container body 1. good.

  As shown in a sealed container 500 (a lid is not shown) shown in FIG. 4D, a rib-shaped reinforcing ring 12 is provided on the outer wall of the mouth 3 or the shoulder 8 along the circumferential direction. preferable. Since the reinforcing ring 12 has a reinforcing effect against the deformation of the mouth portion 3 in the caliber direction, when the trunk portion (not shown in FIG. 4 (d)) is subjected to stress that is crushed in the trunk diameter direction, Propagation of crushing tends to stop at the reinforcing ring 12. The reinforcing ring 12 suppresses deformation at the close contact portion as it is closer to the sealed portion, that is, the close contact portion between the annular convex portion 6 and the annular concave portion 7 as shown in FIG. 1, and as a result, the seal is broken and leads to leakage. Although the number of cases decreases, on the other hand, the ease of drinking may be impaired. Therefore, it is provided in any place on the outer wall of the mouth 3 or the shoulder 8 in consideration of the ease of drinking and the design of the container.

  Note that the reinforcing ring 12 of the sealed container 500 shown in FIG. 4D may be used as the ring 13 for hooking and holding the neck ring 14 or the knob 15 shown in FIG.

  Each structure in which the deformation of the mouth part 3 shown in FIGS. 4A to 4D is suppressed may be incorporated in the container alone, or two or more structures may be combined in the container at the same time. .

  Since the shoulder portion does not exist when the container body is formed into a cup shape, the deformation of the mouth can be suppressed by incorporating each structure shown in FIG. 5 into the container body. FIG. 5 is a schematic view in a longitudinal section of a resealable sealed container having a cup-shaped container body according to the present embodiment, where (a) is reinforced by increasing the wall thickness, and (b) is a wall. (C) shows the case of reinforcing with a rib-like reinforcing ring. In FIG. 5A, since at least the lower part 25 than the mouth part 3 is formed with a wall thicker than the body part 4, even if the container body is formed in a cup shape, The deformation at 4 is difficult to be transmitted to the mouth 3. In FIG. 5 (b), since at least the lower part 25 is crystallized from the mouth part 3, even if the container body is formed in a cup shape, the deformation at the body part 4 is hardly transmitted to the mouth part 3. . The entire container may be crystallized. In FIG.5 (c), since the rib-shaped reinforcement ring 12 is provided in the outer wall of the opening | mouth part 3 or the lower part 25 rather than the opening | mouth part 3 along the circumferential direction, even if the container trunk | drum is formed in cup shape The deformation at the body 4 is not easily transmitted to the mouth 3. The principle of reinforcement of each structure is the same as that of each of FIGS. You may incorporate combining each structure shown to Fig.5 (a)-(c).

  In the sealed container having resealability according to this embodiment, the bottle-shaped sealed container shown in FIGS. 1, 3 and 4 or the cup-shaped sealed container shown in FIG. Thus, when the stress 10 is applied and the body part 4 is crushed by 10% in the body diameter direction, the deformation rate calculated by (Equation 1) in the diameter direction of the mouth part 3 is 0.50% or less. Is preferred. Depending on the volume of the container or the diameter of the body 4 or the diameter of the mouth 3, the allowable deformation rate in the mouth 3 direction in securing the sealing performance varies. In the case of a beverage bottle, it is possible to prevent the contents from leaking due to the deformation of the close contact portion between the annular convex portion 6 and the annular concave portion 7 by the deformation rate being 0.50% or less. Therefore, by providing a structure in which the deformation of the mouth portion is suppressed such that the deformation rate is 0.50% or less, the sealing performance of the lid 2 can be secured, and leakage of the contents can be almost eliminated.

  In the sealed container having resealability according to the present embodiment, as shown in FIG. 1, a rib-like neck ring 14 is further provided on the barrel 4 side of the tubular outer wall of the mouth portion 3 than the annular convex portion 6. It is preferable that a flange 16 is provided on the tube end portion of the lid 2 toward the outside, and the neck ring 14 and the flange 16 are fused. In FIG. 1, a portion where the close contact portion 19 between the neck ring 14 and the flange 16 is fused is shown. Even if the contents are, for example, carbonated drinks, it is possible to prevent the lid from popping out. It can also be confirmed whether or not it has been opened until it reaches the consumer.

  The adhesion portion 19 is preferably fused by a laser welding method. Compared with the case where heat fusion is performed using a heater as a heat source, the boundary between the fused portion and the non-fused portion is clear, and high-precision fusion is possible. The fusion-scheduled portion serving as the fusion portion, that is, the close contact portion 19 is formed of a material that absorbs laser light so that the laser light is easily absorbed, or a paint that absorbs laser light is applied to the close contact portion 19. It is good also as having been apply | coated or the object which consists of a material which absorbs a laser beam in the contact | adherence part 19 is arrange | positioned. When fusing by the laser welding method, even when the object to be fused does not absorb the laser beam, the adhesion portion 19 can be directly heated by coloring the adhesion portion 19 so as to absorb laser light. In order to form the contact portion 19 with a material that absorbs laser light, for example, the container body 1 and / or the lid 2 are formed by adding a dye or a pigment to a plastic resin. In order to apply the contact portion 19 with a paint that absorbs laser light, for example, the paint is printed by various printing methods. Examples of the material that absorbs laser light that is disposed in the close contact portion 19 include a material that is applied to the same material as the container body 1 or the lid 2 or that contains a dye or a pigment. Thus, by providing the absorption part with respect to a laser beam, the absorptance of a laser becomes high and it becomes possible to perform laser welding with small energy. The dye or pigment is, for example, a metal material, ceramic, or organic pigment, and absorbs laser light. It is preferable to adjust the wavelength of the laser light, the laser power, and the laser scanning speed according to the degree of absorption of the absorbing portion with respect to the laser light.

A laser oscillation element used for laser welding is, for example, a semiconductor laser, a gas laser such as a carbon dioxide gas laser, or a YAG laser. The material is appropriately selected according to various parameters such as the material of the container body 1 and the lid 2 to be laser welded, the laser irradiation moving speed, and the irradiation spot shape. The wavelength of the laser beam is preferably a semiconductor laser having a wavelength of 800 to 1000 nm, for example. It is preferable that the energy density of the laser light irradiated to the contact portion 19 is, for example, 150 J per 1 cm ² of the fusion area. The fusion can be completed without causing thermal deformation.

  In the present embodiment, the following welding method can be applied instead of the laser welding method. That is, the sealed portion 19 is manufactured by fusing the contact portion 19 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. .

The impulse sealing method is a method in which the close contact portion 19 is heated and welded by rapidly applying a strong current to the ribbon heater. The high-frequency welding method is a welding method by internal heating in which a high-frequency current is absorbed by the contact portion 19 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 the close contact portion 19 is rubbed in place of spin to generate heat and melt adhesion. The spin welding method is a method in which the close contact portion 19 is rotated and rubbed together and melt welded by frictional heat. The ultrasonic welding method is a method in which ultrasonic vibration energy is applied to melt and bond the close contact portion 19. The hot air welding method is a method in which air or gas is sent to a heated heater and is blown and welded to the contact portion 19. The heat sealing method is a method in which welding is performed by heating under pressure in a state where the close contact portion 19 is sandwiched between heating plates.
Each welding method can be appropriately selected and used according to the shape of the container.

  In the sealed container having resealability according to the present embodiment, the lid pop-out prevention mechanism shown in FIG. 6 may be provided in order to prevent the lid from popping out further than the lid pop-out mechanism shown in FIG. FIG. 6 is a schematic view showing another embodiment of the lid pop-out prevention mechanism. The sealed container 900 shown in FIG. 6 is further provided with a knob 30 on the lid 2, and a rib-like neck ring 32 with a notch 31 is provided on the body side of the cylindrical outer wall of the mouth portion 3 with respect to the annular convex portion 6. And a mechanism for preventing the lid 2 from popping out by hooking the knob 30 on the notch 31. Even if the content is, for example, a carbonated drink, the lid 2 can be prevented from popping out.

  The figure is a schematic view showing a form example in which the sealed container according to this embodiment is covered with a shrink film cover. In the sealed container having resealability according to the present embodiment, as shown in FIG. 7, the sealed container 100 includes the shrink film cover 40 that covers the mouth 3 and the lid 2 that seals the mouth 3. It is preferable. The lid can be reliably prevented from popping out until it reaches the consumer. Moreover, the presence or absence of opening can be confirmed.

  In the sealed container having resealability according to the present embodiment, it is preferable that a gas barrier thin film is formed on the surface of at least one of the container body 1 and the lid 2. By improving the gas barrier properties of the container, the expiration date or expiration date can be extended. Examples of the gas barrier thin film include a diamond-like carbon (DLC) film, a Si-containing DLC film, and a SiOx film. As a method for forming a gas barrier thin film, a known film forming method can be used. For example, there are techniques disclosed in Japanese Patent No. 2788412, Japanese Patent No. 3072269, or Japanese Patent No. 3115252. The gas barrier thin film is formed on the inner or outer surface of the container body 1 and on the inner or outer surface of the lid 2. More preferably, a gas barrier thin film is formed on the inner surface or the outer surface of both the container body 1 and the lid 2.

(Sample 1)
A lid of the type shown in FIG. 1 was molded by a compressed air method using an amorphous PET resin sheet (Denka A-PET sheet). The outer diameter of the lid was 21.7 mm. At this time, the area of the top surface was 3.71 cm ² . At this time, the thickness of the lid was 485 μm. The thickness of the lid was measured at the location of the annular recess. Three of these were prepared (n = 3). The density of the lid was 1.326 g / cm ³ . Since it is difficult to accurately measure the crystallinity of the lid, the density that changes due to the difference in crystallinity was used as an index of crystallinity. There is a relationship that the higher the density, the higher the crystallinity, and the lower the density, the lower the crystallinity. The density was measured using a density gradient method specific gravity measuring instrument (Asahi Glass Works Co., Ltd.). In addition, as a premise of density measurement, it was confirmed that the measurement sample showed the heat absorption characteristics of PET by the DSC method and there was no endothermic / exhaust heat peak of other components (device used: DSC-60 Shimadzu Corporation). After attaching the lid to the container body made of PET resin, after removing the lid 10 times, if the lid cracks, it does not have crack resistance (denoted as x), and the lid is cracked. When it did not occur, it was evaluated as having crack resistance (denoted as ◯). The results are shown in Table 1.

(Sample 2 to Sample 10)
Crack resistance was evaluated by changing the density, thickness, and molding method of the lid, and the results are shown in Table 1. Table 1 also shows the lid density, thickness, and molding method conditions.

The following can be seen from the results in Table 1. The lid is preferably formed of an amorphous polyethylene terephthalate resin having a thickness of 80 μm or more and less than 390 μm and a density of 1.320 to 1.340 g / cm ³ . At this time, since the lid has necessary and sufficient flexibility, cracks due to repeated opening and closing of the lid do not occur.

  A sealed container of the type shown in FIG. 1 was prepared, and the container body was filled with water, and then a sample 4 lid was attached. When the trunk was crushed in the range of 1 cm to 2 cm as shown in FIG. 3, the deformation rate of the mouth was calculated, and the presence or absence of water leakage was examined. The deformation rate was calculated by (Equation 1). The results are shown in Table 2.

  From the results in Table 2, it was found that no leakage occurred when the deformation rate was 0% or more and less than 0.52%.

The schematic in the longitudinal cross-section of one form of the sealed container which has resealability concerning this embodiment was shown. Fig. 4 shows a lid forming process using a compressed air method, wherein (a) shows a sheet heating stage, (b) shows a compressed air forming stage, and (c) shows a demolding stage. It is the schematic which shows the mode of a deformation | transformation when stress is applied to the sealed container 100 shown in FIG. 1, (a) has shown the state before a deformation | transformation, (b) has shown the state after a deformation | transformation. It is the schematic in the longitudinal cross-section of the other form of the sealed container which has the resealability which concerns on this embodiment, and (a) has a shoulder part shape which changed the ratio reduced in diameter from a trunk | drum to a mouth part, b) has a shoulder formed with a thick wall compared to the body, (c) has a crystallized shoulder, and (d) surrounds the outer wall of the mouth or shoulder. This is when a rib-shaped reinforcing ring is provided along the direction. It is the schematic in the longitudinal cross-section of the sealed container which has resealability which has the cup-shaped container trunk | drum which concerns on this embodiment, (a) is reinforced by the wall thickness increase, (b) is crystallization of a wall (C) is a case where it is reinforced by a rib-shaped reinforcing ring. It is the schematic which shows the other form of the protrusion prevention mechanism of a lid | cover. It is the schematic which shows the form example which coat | covered the shrink film cover to the sealed container.

Explanation of symbols

1, container body 2, lid 3, mouth part 4, body part 5, top surface 6, 6 a, 6 b, annular convex part 7, 7 a, 7 b, annular concave part 8, shoulder part 10, stress 11, crushing 12, Reinforcing ring 13, rings 14 and 32, neck rings 15 and 30, knob 16, flange 18, hook portion 19, close contact portion 21, heating plate 22, mold 23, sheet 24, compressed air 25, more than the mouth Lower part 31, notch 40, shrink film cover 100, 200, 300, 400, 500, 600, 700, 800, 900,
Sealed container X, container shaft

Claims (14)

In a sealed container having resealability, comprising a container body having a cylindrical mouth portion, and a lid that is formed in a cylindrical shape with a top surface and that seals the mouth portion by being fitted from the outside of the mouth portion,
The container body has a structure in which the deformation of the body portion is limited to the inside of the body portion when stress is applied to the body portion, and the deformation of the mouth portion is suppressed, and the container body is made of polyethylene terephthalate resin. Molded,
The mouth portion has an annular convex portion connected to the outer wall of the cylinder along the circumferential direction,
The lid is made of an amorphous polyethylene terephthalate resin having a continuous annular recess for fitting the annular protrusion along the circumferential direction on the inner wall of the cylinder, and having a density of 1.320 to 1.340 g / cm ^3. A sealed container having resealability, which is molded and has a wall thickness of 80 μm or more and less than 390 μm.   The sealed container according to claim 1, wherein the lid is formed by a compressed air method or a vacuum method.   The sealed container having resealability according to claim 1 or 2, wherein the container body is formed by blow molding or injection molding.   The resealability according to claim 1, 2, or 3, wherein the top surface of the lid is pulled upward, and the adhesion of the lid measured until the lid is opened is 9.8 N or more. Having sealed container.   In the structure in which the deformation of the mouth portion is suppressed, the container body has a body portion that has a maximum or substantially maximum body diameter and is a gripping portion at a portion separated by 30 mm or more from the mouth portion. The sealed container having resealability according to claim 1, 2, 3, or 4, characterized in that a shoulder portion is provided between the portion and the mouth portion.   6. The sealed container having resealability according to claim 5, wherein the shoulder portion has a shape in which a ratio of diameter reduction from the trunk portion to the mouth portion is changed. The structure in which the deformation of the mouth is suppressed is
At least the shoulder is a structure formed of a thick wall compared to the trunk, or
Or at least the shoulder is crystallized, or
The outer wall of the mouth or shoulder is a structure provided with a rib-shaped reinforcing ring along the circumferential direction, or
The sealed container having resealability according to claim 5 or 6, which is a combination of these structures. The container body is formed in a cup shape, and the structure in which deformation of the mouth portion is suppressed,
At least the lower part than the mouth part is a structure formed by a wall thicker than the body part, or
Or at least a portion below the mouth is crystallized, or
It is a structure in which a rib-like reinforcing ring is provided along the circumferential direction on the outer wall of the mouth or the lower part of the mouth, or
The sealed container having resealability according to claim 1, 2, 3, or 4, which is a combination of these structures. The deformation rate calculated by (Equation 1) in the caliber direction of the mouth part when the body part is crushed by 10% in the body diameter direction is 0.50% or less. A sealed container having resealability according to 3, 4, 5, 6, 7 or 8.
(Equation 1) Deformation rate (%) = {(minimum diameter when unloaded−minimum diameter when deformed) / minimum diameter when unloaded} × 100   The deformation amount of the mouth portion is smaller than the deformation amount of the lid when a predetermined load is applied to an outer peripheral portion of a region where the lid and the mouth overlap. A sealed container having resealability according to 5, 6, 7, 8 or 9.   Further, a rib-like neck ring is provided on the barrel side of the tubular outer wall of the mouth portion with respect to the annular convex portion, a flange is provided outward on the tube end portion of the lid, and the neck ring and the The sealed container with resealability according to claim 1, 2, 3, 4, 5, 6, 7, 8, 9 or 10, wherein the flange is fused.   Further, a knob is provided on the lid, a rib-like neck ring with a notch is provided on the barrel side of the cylindrical outer wall of the mouth part, and the knob is hooked on the notch. 12. A sealed container having resealability according to claim 1, further comprising a mechanism for preventing the lid from popping out according to claim 1, 2. 3, 4, 5, 6, 7, 8, 9, 10 or 11. .   It has a shrink film cover which coat | covered the said opening part and the said lid | cover which has sealed this opening part, The 1, 2, 3, 4, 5, 6, 7, 8, 9, 10, A sealed container having resealability according to 11 or 12. A gas barrier thin film is formed on the surface of at least one of the container body and the lid, characterized in that: A sealed container having resealability according to 11, 12, or 13.

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