Cap and container

Abstract

To provide a cap which is manufactured using resin containing an alicyclic structure-containing polymer and which can suppress the formation of a gap when attached to a mouth part of a container body.SOLUTION: A cap comprises: an outer cylindrical part having an inner peripheral surface on which a screw thread is formed; a lid part formed at one end of the outer cylindrical part; and an inner plug part formed inside the outer cylindrical part to be connected to the lid part and made of resin containing an alicyclic structure-containing polymer. The inner plug part has an outer peripheral surface with a gap between the outer cylindrical part and itself and the outer peripheral surface of the inner plug part includes a surface part formed so as to have a larger diameter as it approaches the lid part.SELECTED DRAWING: Figure 1

Description

[Technical Field]

[0001] The present invention relates to a cap and a container equipped with the cap. [Background technology]

[0002] Containers made of thermoplastic resins are used in a variety of industrial fields due to their light weight and ease of mass production (see Patent Documents 1 to 4). Such containers may be provided with a cap in addition to the container body. [Prior art documents] [Patent documents]

[0003] [Patent Document 1] Japanese Patent Application Publication No. 11-74337 [Patent Document 2] Patent No. 7381399 [Patent Document 3] Japanese Patent Application Laid-Open No. 2013-34567 [Patent Document 4] Patent Publication No. 2021-113088 Summary of the Invention [Problem to be solved by the invention]

[0004] Conventionally, resins such as polyethylene, polypropylene, and polyethylene terephthalate have often been used as materials for containers. However, although these resins are inexpensive, when used to store medicinal liquids used in medical products or cosmetics, the active ingredients of the chemicals tend to adhere to the inside of the container. Therefore, the present inventors focused on resins containing alicyclic structure-containing polymers as resins to which the active ingredients of medicinal liquids are less likely to adhere, and attempted to manufacture containers using these resins.

[0005] Specifically, the present inventors attempted to manufacture a container body and a cap using a resin containing an alicyclic structure-containing polymer. However, it was found that in containers manufactured using such a resin containing an alicyclic structure-containing polymer, a gap is likely to form between the container body and the cap when the cap is attached to the mouth of the container body. If such a gap exists, the chemical solution may volatilize or evaporate through the gap, or water vapor or foreign matter may enter from the outside.

[0006] The present invention was devised in view of the above-mentioned problems, and aims to provide a cap that is manufactured using a resin containing an alicyclic structure-containing polymer and that can suppress the formation of gaps when attached to the mouth of a container body; and a container equipped with such a cap. [Means for solving the problem]

[0007] The present inventors have conducted extensive research to solve the above-mentioned problems, and as a result, have found that the above-mentioned problems can be solved by forming a surface portion having a larger diameter closer to the lid portion on the outer circumferential surface of an inner plug portion connected to the lid portion of a cap and made of a resin containing an alicyclic structure-containing polymer, and have thus completed the present invention. That is, the present invention includes the following.

[0008] <1> an outer tubular portion having an inner circumferential surface on which a thread is formed; a lid portion formed at one end of the outer cylinder portion; a cap including an inner plug portion connected to the lid portion and formed of a resin containing an alicyclic structure-containing polymer, the inner plug portion being disposed within the outer cylindrical portion; the inner plug portion has an outer circumferential surface formed with a gap between it and the outer cylindrical portion; A cap, wherein the outer peripheral surface of the inner plug portion includes a surface portion formed to have a larger diameter as it approaches the lid portion. <2> The surface portion is formed continuously from the end portion of the outer peripheral surface of the inner plug portion on the lid portion side. <1> The cap described in <3> The entire outer peripheral surface of the inner plug portion forms the surface portion. <1> or <2> The cap described in <4> A hollow portion extending in the axial direction of the cap is formed in the inner plug portion. <1> ~ <3> The cap described in any one of the above. <5> the lid portion includes a first lid portion connected to the outer cylinder portion, and a second lid portion formed inside the first lid portion and connected to the inner plug portion; The second lid portion contains a resin containing an alicyclic structure-containing polymer. <1> ~ <4> The cap described in any one of the above. <6> A protruding portion protruding radially inward is formed at one or more axial portions of the inner edge of the first lid portion, A recessed portion recessed radially inward is formed in one or more axial portions of an outer edge portion of the second lid portion, The protruding portion of the first lid portion and the recessed portion of the second lid portion are engaged with each other. <5> The cap described in <7> A convex portion protruding radially inward is formed at one or more circumferential portions of the inner edge of the first lid portion, A recess recessed radially inward is formed in one or more circumferential portions of the outer edge of the second lid portion, The protrusion of the first cover portion and the recess of the second cover portion are engaged with each other. <5> or <6> The cap described in <8> <1> ~ <7> a cap according to any one of the preceding claims; a container body having a mouth formed so that the cap can be attached. [Effects of the Invention]

[0009] According to the present invention, it is possible to provide a cap that is manufactured using a resin containing an alicyclic structure-containing polymer and that can suppress the formation of gaps when attached to the mouth of a container body; and a container that is equipped with the cap. [Brief explanation of the drawings]

[0010] [Figure 1] FIG. 1 is a front view schematically showing a container according to one embodiment of the present invention. [Figure 2]FIG. 2 is a perspective view schematically showing the periphery of the mouth of a container body provided in a container according to one embodiment of the present invention, together with a cap. [Figure 3] FIG. 3 is a cross-sectional view schematically showing a cap provided on a container according to one embodiment of the present invention. [Figure 4] FIG. 4 is a top view schematically showing a cap provided on a container according to one embodiment of the present invention. [Figure 5] FIG. 5 is a cross-sectional view schematically showing the periphery of a mouth portion of a container according to one embodiment of the present invention, to which a cap is attached. [Figure 6] FIG. 6 is a cross-sectional view that schematically shows the periphery of the mouth of a container body to which a cap that does not have an inclined surface portion is attached. DETAILED DESCRIPTION OF THE INVENTION

[0011] The present invention will be described in detail below with reference to embodiments and examples. However, the present invention is not limited to the embodiments and examples shown below, and may be modified and implemented within the scope of the claims and their equivalents.

[0012] In the following description, unless otherwise specified, the directions of elements as "parallel," "vertical," and "orthogonal" may include an error within a range that does not impair the effects of the present invention, for example, within a range of ±3°, ±2°, or ±1°.

[0013] <Embodiment relating to container> 1 is a front view schematically showing a container 10 according to one embodiment of the present invention. As shown in FIG. 1, the container 10 according to one embodiment of the present invention includes a container body 100 and a cap 200.

[0014] The container body 100 includes a base 110 having a storage chamber (not shown) formed therein for storing contents, and a mouth 120 formed to allow the cap 200 to be attached. A flange 111 is formed at the end of the base 110 on the mouth 120 side, extending radially from the container body 100 to cover the axial end of the cap 200 and prevent foreign matter from entering the gap between the container body 100 and the cap 200. A gripping portion 112 having a larger outer diameter than the other portions is formed at a portion of the axial direction of the base 110. The gripping portion 112 may have multiple knurled grooves 113 formed therein to prevent slippage. Furthermore, a ring 114 is formed between the flange 111 and the gripping portion 112, and is thicker than the other portions to improve durability against stress when the cap 200 is attached or detached.

[0015] FIG. 2 is a perspective view schematically showing the periphery of the mouth 120 of the container body 100 provided in the container 10 according to one embodiment of the present invention, together with the cap 200. As shown in FIG. 2, the mouth 120 is formed and connected to the base 110. The mouth 120 has an opening 121 that communicates with a storage chamber in the base 110, and the cap 200 is attached to close this opening 121. An outer peripheral surface 122 of the mouth 120 has a thread 123 that can be threadably engaged with a thread 212 of the cap 200. The opening 121 and the inner peripheral surface 124 of the mouth 120 that is continuous therewith are formed in a circular shape when viewed in the axial direction of the container body 100. Therefore, when the mouth 120 is cut along a plane perpendicular to the axial direction of the container body 100, the shape of the inner peripheral surface 124 in the cross section is circular. In this embodiment, an example will be described in which the mouth portion 120 has a constant inner diameter in the axial direction of the container body 100, and therefore the inner circumferential surface 124 has a cylindrical circumferential shape. The inner edge portion 125 at the tip of the mouth portion 120 may be chamfered to allow the inner plug portion 230 of the cap 200 to be inserted smoothly.

[0016] The materials of the container body 100 and each part included in the container body 100 are not particularly limited. For example, inorganic materials such as glass may be used, or organic materials such as thermoplastic resins may be used. Examples of thermoplastic resins include polyester resins; polypropylene resins; polyethylene terephthalate resins; polyacetal resins; acrylic resins such as polymethyl methacrylate; polycarbonate resins; and resins containing polymers containing alicyclic structures. Among these thermoplastic resins, resins containing polymers containing alicyclic structures are preferred. Resins containing polymers containing alicyclic structures may be referred to as "specific resins" hereinafter.

[0017] Fig. 3 is a cross-sectional view schematically showing the cap 200 provided in the container 10 according to one embodiment of the present invention. Fig. 4 is a top view schematically showing the cap 200 provided in the container 10 according to one embodiment of the present invention. As shown in Figs. 3 and 4, the cap 200 includes an outer tube portion 210, a lid portion 220, and an inner plug portion 230.

[0018] As shown in Fig. 3, the outer cylindrical portion 210 is formed in a cylindrical shape so that the mouth portion 120 of the container body 100 can be inserted into the outer cylindrical portion 210. The outer cylindrical portion 210 has an inner peripheral surface 211. The inner peripheral surface 211 is formed with threads 212 that can be threadably engaged with the threads 123 of the mouth portion 120. The outer cylindrical portion 210 also has an outer peripheral surface 213. As shown in Fig. 4, the outer peripheral surface 213 may be formed with a number of knurled grooves 214 to prevent slippage.

[0019] The lid portion 220 is formed at one axial end of the outer tubular portion 210 so as to close one opening of the space inside the outer tubular portion 210. The lid portion 220 may be formed of a single member, or may be formed of multiple members. In this embodiment, an example will be described in which the lid portion 220 includes a first lid portion 221 formed on the outer side in the radial direction of the cap 200 and a second lid portion 222 formed on the inner side.

[0020] As shown in FIG. 3 , the first lid portion 221 is formed and connected to the outer tube portion 210. The first lid portion 221 has an inner edge portion 221E as an inner edge portion of the first lid portion 221 in the cap radial direction. Since the first lid portion 221 and the second lid portion 222 are normally joined together, the inner edge portion 221E of the first lid portion 221 is joined to the outer edge portion 222E of the second lid portion 222. A protruding portion 223 is formed on the inner edge portion 221E of the first lid portion 221 so as to be able to engage with the recessed portion 225 of the second lid portion 222. The protruding portion 223 is formed by one or more portions of the inner edge portion 221E in the cap axial direction protruding radially inward of the cap 200. In this embodiment, an example will be described in which the protruding portion 223 is formed by a portion where the inner plug portion 230 side end of the inner edge portion 221E of the first lid portion 221 protrudes radially inward beyond the opposite end thereof. The protruding portion 223 may be formed on a part of the inner edge portion 221E in the circumferential direction of the cap 200, or may be formed on the entire inner edge portion 221E.

[0021] As shown in Fig. 4, a protrusion 224 is formed on the inner edge 221E of the first lid portion 221 so as to be able to engage with the recess 226 of the second lid portion 222. This protrusion 224 is formed by one or more portions of the inner edge 221E in the circumferential direction of the cap projecting radially inward of the cap 200. In this embodiment, an example in which the protrusions 224 are formed in two locations, the upper and lower portions in Fig. 4, will be described. The protrusion 224 may be formed on a part of the inner edge 221E or on the entire inner edge 221E in the axial direction of the cap 200.

[0022] As shown in FIG. 3 , the second lid portion 222 is formed inside the first lid portion 221 in the radial direction of the cap 200 so as to be connected to the inner plug portion 230. The second lid portion 222 has an outer edge portion 222E as an outer edge portion of the second lid portion 222 in the cap radial direction, and this outer edge portion 222E is joined to the inner edge portion 221E of the first lid portion 221. A recessed portion 225 is formed in the outer edge portion 222E of the second lid portion 222, and this recessed portion 225 engages with the protruding portion 223 of the first lid portion 221. The recessed portion 225 is formed by recessing one or more portions of the outer edge portion 222E in the cap axial direction toward the radially inward direction of the cap 200. In this embodiment, an example will be described in which the recessed portion 225 is formed by a portion where the inner plug portion 230 side end of the outer edge portion 222E of the second lid portion 222 is recessed radially inward relative to the opposite end. The recessed portion 225 may be formed in a part of the outer edge portion 222E in the circumferential direction of the cap 200, or may be formed over the entire outer edge portion 222E.

[0023] As shown in Fig. 4, a recess 226 is formed in the outer edge 222E of the second lid portion 222, and this recess 226 engages with the protrusion 224 of the first lid portion 221. This recess 226 is formed by recessing one or more portions of the outer edge 222E in the circumferential direction of the cap toward the radially inner side of the cap 200. In this embodiment, an example in which the recesses 226 are formed in two places, the upper and lower parts in Fig. 4, will be described. The recess 226 may be formed in a part of the outer edge 222E or may be formed all over the outer edge 222E in the axial direction of the cap 200.

[0024] As shown in Fig. 2, the inner plug portion 230 is formed in the outer tube portion 210 so as to be able to be inserted into the opening 121 of the mouth portion 120 of the container body 100. When the inner plug portion 230 is inserted into the opening 121 of the mouth portion 120, the opening 121 is closed. As shown in Fig. 3, the inner plug portion 230 is formed so as to be connected to the lid portion 220. In this embodiment, an example will be described in which the inner plug portion 230 is formed so as to be connected to the second lid portion 222 of the lid portion 220.

[0025] The inner plug portion 230 has an outer peripheral surface 231 formed with a gap 240 between it and the outer tube portion 210. The outer peripheral surface 231 of the inner plug portion 230 includes a surface portion 232 formed over the entire circumferential direction of the cap so that the diameter increases toward the lid portion 220. This surface portion 232 is inclined with respect to the axial direction of the cap 200 and may be referred to as an "inclined surface portion" 232 hereinafter. This inclined surface portion 232 may be inclined with respect to the axial direction of the cap 200 so that the position in the radial direction of the cap becomes more outward as it approaches the lid portion 220. The inclined surface portion 232 is preferably formed continuously from an end 231E of the outer peripheral surface 231 of the inner plug portion 230 on the lid portion 220 side. In one example, the entire outer peripheral surface 231 of the inner plug portion 230 may form the inclined surface portion 232.

[0026] The inclined surface portion 232 of the inner plug portion 230 is formed in a circular shape when viewed in the axial direction of the cap 200. Usually, the entire outer peripheral surface 231 of the inner plug portion 230, including the inclined surface portion 232, is formed in a circular shape when viewed in the axial direction of the cap 200. Therefore, when the inner plug portion 230 is cut along a plane perpendicular to the axial direction of the cap 200, the shape of the inclined surface portion 232 in the cross section is circular, and usually the shape of the outer peripheral surface 231 is also circular. In this embodiment, an example will be described in which the entire outer peripheral surface 231 has the shape of the peripheral surface of a truncated cone, and therefore the entire outer peripheral surface 231 forms the inclined surface portion 232.

[0027] The angle θ formed by the inclined surface portion 232 with respect to the axial direction of the cap 200 can be set within a range that achieves the desired effects of the present invention. The specific range of the angle θ is usually greater than 0°, preferably 1° or more, more preferably 1.5° or more, and even more preferably 2° or more, and is preferably 20° or less, more preferably 15° or less, and even more preferably 10° or less.

[0028] The inclined surface portion 232 formed as described above includes a portion formed so that the inclined surface portion 232 can be in close contact with the inner circumferential surface 124 of the mouth portion 120 of the container body 100 when the cap 200 is attached to the container body 100. Therefore, the inclined surface portion 232 may include a portion having the same diameter as the diameter of the inner circumferential surface 124 of the mouth portion 120, and may also include a portion having a larger diameter than the diameter of the inner circumferential surface 124 of the mouth portion 120. Typically, a portion of the inclined surface portion 232 in the cap axial direction has a diameter that is the same as or larger than the diameter of the inner circumferential surface 124 of the mouth portion 120 of the container body 100 so that the inclined surface portion 232 can be in close contact with the inner circumferential surface 124 of the mouth portion 120 of the container body 100.

[0029] A hollow portion 233 may be formed inside the inner plug portion 230. The hollow portion 233 is preferably formed to extend in the axial direction of the cap 200. For example, a cylindrical hollow portion 233 may be formed with its center on the rotation axis of the cap 200. From the viewpoint of smoothly manufacturing the cap 200 by a molding method, it is preferable that the hollow portion 233 be open on the side opposite the lid portion 220. In this embodiment, an example will be described in which the inner plug portion 230 has a cylindrical shape with one end in the cap axial direction closed, and therefore a cylindrical hollow portion 233 is formed therein.

[0030] Among the components included in the cap 200, the inner plug portion 230 is formed from a specific resin containing an alicyclic structure-containing polymer. Therefore, the inner plug portion 230 may contain the specific resin, or may contain only the specific resin. Furthermore, the components other than the inner plug portion 230, such as the outer tube portion 210 and the lid portion 220, are preferably formed from a thermoplastic resin, and may be formed from, for example, the thermoplastic resins described as examples of materials for the container body 100. In particular, when the lid portion 220 includes a second lid portion 222 connected to the inner plug portion 230 as described above, the second lid portion 222 is preferably formed from a specific resin. Therefore, the second lid portion 222 preferably contains the specific resin, or may contain only the specific resin. On the other hand, preferred resins for forming the first lid portion 221 include polyester resin, polypropylene resin, polyacetal resin, polymethylpentene, thermoplastic elastomer, etc.

[0031] The container 10 according to this embodiment has the above-described configuration. Therefore, when using the container 10, contents (not shown) are placed in the container body 100, and the cap 200 is attached to the mouth portion 120 of the container body 100. The cap 200 is attached to the mouth portion 120 by threading the thread 212 formed on the inner circumferential surface 211 of the outer tubular portion 210 of the cap 200 into the thread 123 formed on the outer circumferential surface 122 of the mouth portion 120 of the container body 100.

[0032] FIG. 5 is a cross-sectional view schematically illustrating the vicinity of the mouth 120 of a container 10 according to one embodiment of the present invention, to which a cap 200 is attached. As shown in FIG. 5, when the cap 200 is attached to the mouth 120 of the container body 100, the inner plug portion 230 of the cap 200 can fit into the opening 121 of the mouth 120. Specifically, when the cap 200 is attached to the mouth 120, the mouth 120 enters the gap 240 between the outer tube portion 210 and the inner plug portion 230 of the cap 200. At this time, since the inclined surface portion 232 is formed on the outer peripheral surface 231 of the inner plug portion 230, a portion of the inner peripheral surface 124 of the mouth 120 in the axial direction comes into contact with the inclined surface portion 232 included in the outer peripheral surface 231 of the inner plug portion 230. Typically, the tip of the inner peripheral surface 124 comes into contact with a portion of the axial direction of the outer peripheral surface 231 of the inner plug portion 230, as shown in contact region 126 surrounded by a dashed line. Furthermore, the inner circumferential surface 124 of the mouth portion 120 and the outer circumferential surface 231 of the inner plug portion 230 are not in contact with each other and are separated from each other in areas other than the contact area 126. Therefore, the inner circumferential surface 124 of the mouth portion 120 and the inclined surface portion 232 of the inner plug portion 230 can be tightly attached to each other in the small area of ​​the contact area 126, which enables them to be tightly attached with strong pressure and prevents gaps from being formed between them.

[0033] The above advantages will be explained in comparison with an example using a cap with an inner plug portion that does not have the inclined surface portion 232. Fig. 6 is a cross-sectional view that schematically shows the periphery of the mouth portion 120 of the container body 100 to which a cap 900 that does not have the inclined surface portion 232 is attached. As shown in Fig. 6, the cap 900 is formed in the same manner as the cap 200 according to the above-described embodiment, except that an inner plug portion 930 having an outer peripheral surface 931 parallel to the axial direction of the cap 900 is formed instead of the inner plug portion 230 according to the above-described embodiment.

[0034] The outer peripheral surface 931 of the inner plug portion 930 of this cap 900 is parallel to the cap axial direction and therefore does not have an inclined surface portion 232. Therefore, when the cap 900 is attached to the mouth portion 120 of the container body 100, the inner peripheral surface 124 of the mouth portion 120 and the outer peripheral surface 931 of the inner plug portion 930 become parallel, allowing them to contact over a wide area. Here, the specific resin is generally a hard resin and therefore has low flexibility. Therefore, the outer peripheral surface 931 of the inner plug portion 930 containing the specific resin is less likely to deform along the inner peripheral surface 124 of the mouth portion 120. Therefore, even if an attempt is made to bring the inner peripheral surface 124 of the mouth portion 120 and the outer peripheral surface 931 of the inner plug portion 930 into close contact by deformation due to pressure, a small gap (not shown) is likely to form between the inner peripheral surface 124 of the mouth portion 120 and the outer peripheral surface 931 of the inner plug portion 930. Such gaps can cause the solvent in the contents to evaporate and the contents to deteriorate (oxidize, spoil, etc.) due to the intrusion of outside air. Furthermore, particularly when mouth portion 120 is formed from a specific resin, the frictional force between inner circumferential surface 124 of mouth portion 120 and outer circumferential surface 931 of inner plug portion 930 can be large. Therefore, in this case, the force required to rotate cap 200 increases, and therefore the force required to attach cap 200 can also increase.

[0035] In contrast, as shown in FIG. 5, an inclined surface portion 232 is formed on the outer peripheral surface 231 of the inner plug portion 230 of the cap 200 according to this embodiment. Therefore, rather than the inclined surface portion 232 and the inner peripheral surface 124 of the mouth portion 120 contacting each other over a wide area, a portion of the inclined surface portion 232 of the inner plug portion 230 and a portion of the inner peripheral surface 124 of the mouth portion 120 can contact each other over a narrow area throughout the entire circumferential direction. Therefore, at the contact site 126, the inner peripheral surface 124 of the mouth portion 120 and the inclined surface portion 232 of the inner plug portion 230 can be tightly attached with strong pressure. While the specific resin contained in the inner plug portion 230 has low flexibility, it can deform to fill gaps when subjected to sufficiently high pressure, thereby preventing gaps from forming between the two. This prevents solvent evaporation and air from entering through the gaps.

[0036] Furthermore, when the mouth portion 120 is formed from a specific resin, the coefficient of friction between the inner peripheral surface 124 of the mouth portion 120 and the outer peripheral surface 931 of the inner plug portion 930 can be large, but the frictional force can be reduced by narrowing the contact area. Therefore, the force required to rotate the cap 200 can be reduced, and therefore the force required to attach the cap 200 can be reduced.

[0037] Furthermore, when the inner plug portion 230 of the cap 200 is formed from a specific resin, the surface of the inner plug portion 230 that comes into contact with the contents stored in the container 10 is typically formed from the specific resin. Because the alicyclic structure-containing polymer contained in the specific resin generally has low polarity, polar components such as proteins and amino acids are less likely to adsorb to the specific resin containing the alicyclic structure-containing polymer. Therefore, adsorption of polar components in the contents to the inner plug portion 230 can be suppressed, thereby reducing the residue of the contents in the container 10. Furthermore, since the alicyclic structure-containing polymer can be produced with reduced residual monomers, the seepage of impurities such as residual monomers into the contents can be suppressed, thereby preventing the contents from being contaminated with foreign matter. Furthermore, the specific resin containing the alicyclic structure-containing polymer has excellent moldability and formability, making the cap 200 particularly easy to manufacture.

[0038] When the inclined surface portion 232 is formed continuously from the end portion 231E of the outer peripheral surface 231 of the inner plug portion 230 on the lid portion 220 side, as in this embodiment, the inner peripheral surface 124 of the mouth portion 120 and the inclined surface portion 232 of the inner plug portion 230 can usually come into contact with each other deep in the gap 240 between the outer tube portion 210 of the cap 200 and the inner plug portion 230. Therefore, at the initial stage of thread engagement between the thread 123 of the mouth portion 120 and the thread 212 of the cap 200, the inner peripheral surface 124 of the mouth portion 120 and the inclined surface portion 232 of the inner plug portion 230 do not come into contact with each other, and therefore no frictional force is generated between them, and therefore they can be screwed together with little force. Therefore, the period during which a large force is applied to screw together inner circumferential surface 124 of mouth portion 120 and inclined surface portion 232 of inner plug portion 230 in order to bring them into close contact is a short period during the final stage of screwing of threads 123 and 212, so the burden of attaching cap 200 is small, allowing for smooth attachment of cap 200. In particular, when container body 100 contains a specific resin, inner circumferential surface 124 of mouth portion 120 and outer circumferential surface 231 of inner plug portion 230 contain the same material, which can increase the coefficient of friction between them. Therefore, reducing the burden of attaching cap 200 as described above can greatly improve convenience of use.

[0039] When the entire outer peripheral surface 231 of the inner plug portion 230 forms the inclined surface portion 232 as in this embodiment, the cap 200 can be smoothly manufactured by a molding method. Specifically, it is possible to smoothly remove the cap 200 after manufacturing it by molding.

[0040] When a hollow portion 233 is formed in the inner plug portion 230, as in this embodiment, the amount of resin contained in the cap 200 can be reduced, thereby making the cap 200 lighter. Furthermore, since specific resins are typically transparent, a cap 200 equipped with an inner plug portion 230 containing the specific resin can be used in applications that utilize its transparency. For example, if the inner plug portion 230 and the second lid portion 222 connected to the inner plug portion 230 are formed of a transparent specific resin, the contents may be observed through the inner plug portion 230 and the second lid portion 222. In this case, if the hollow portion 233 is formed in the inner plug portion 230, the contents can be observed particularly clearly. Specifically, if the contents contain a component labeled with a fluorescent dye, the component can be clearly observed.

[0041] In the present embodiment, when the lid portion 220 of the cap 200 includes a first lid portion 221 connected to the outer tube portion 210 and a second lid portion 222 connected to the inner plug portion 230, the outer tube portion 210 and the inner plug portion 230 can be formed from different materials. Therefore, the outer tube portion 210 can be formed from a material other than a specific resin. For example, the inner plug portion 230 and the second lid portion 222 can be formed from a transparent specific resin, while the outer tube portion 210 and the first lid portion 221 can be formed from a colored thermoplastic resin. The color or pattern of the cap 200 may be varied to distinguish the contents, and even in this case, the inner plug portion 230 and the second lid portion 222 can be made transparent by utilizing the excellent light transmittance of the specific resin.

[0042] Generally, alicyclic structure-containing polymers have low affinity with polymers other than alicyclic structure-containing polymers. Therefore, specific resins containing alicyclic structure-containing polymers also tend to have poor affinity with thermoplastic resins other than the specific resin. Therefore, when the second lid portion 222 is formed of the specific resin while the first lid portion 221 is formed of a thermoplastic resin other than the specific resin, the bonding strength between the first lid portion 221 and the second lid portion 222 may be weak. In contrast, in this embodiment, the protrusion 223 of the first lid portion 221 and the recessed portion 225 of the second lid portion 222 are engaged with each other, thereby fixing the first lid portion 221 and the second lid portion 222 in the axial direction of the cap 200. Furthermore, the protrusion 224 of the first lid portion 221 and the recessed portion 226 of the second lid portion 222 are engaged with each other, thereby fixing the first lid portion 221 and the second lid portion 222 in the circumferential direction of the cap 200. Therefore, the second lid portion 222 and the inner plug portion 230 connected to the second lid portion 222 are prevented from coming off the cap 200, and the handleability of the cap 200 can be improved.

[0043] The container 10, container body 100, and cap 200 are not limited to those described above and may be further modified. For example, the lid portion 220 may be formed integrally without being divided into the first lid portion 221 and the second lid portion 222. Furthermore, for example, an inclined surface portion 232 may be formed on a part of the outer circumferential surface 231 of the inner plug portion 230 in the cap axial direction, and the other part of the outer circumferential surface 231 may be formed parallel to the cap axial direction.

[0044] There are no limitations on the manufacturing method of the container 10, the container body 100, and the cap 200. Preferably, the cap 200 can be manufactured by a molding method. Among these, a molding method using a mold is preferred. In a molding method, the cap 200 is manufactured by a method including molding a thermoplastic resin using a mold. In particular, when manufacturing the cap 200 including the first lid portion 221 and the outer tube portion 210 connected thereto, and the second lid portion 222 and the inner plug portion 230 connected thereto, as in the above-described embodiment, it is preferable to manufacture the cap 200 by a two-color molding method or an insert molding method. The two-color molding method and the insert molding method allow the first lid portion 221 and the outer tube portion 210 connected thereto, and the second lid portion 222 and the inner plug portion 230 connected thereto to be integrally molded. Here, "integral molding" refers to molding in which multiple components are joined to each other to form a single component.

[0045] The two-color molding method typically includes molding a specific resin in a first mold to form the second lid portion 222 and the inner plug portion 230, placing the second lid portion 222 and the inner plug portion 230 in a second mold, and molding a thermoplastic resin in the second mold to form the first lid portion 221 and the outer tube portion 210. Alternatively, the two-color molding method may include molding a thermoplastic resin in a first mold to form the first lid portion 221 and the outer tube portion 210, placing the first lid portion 221 and the outer tube portion 210 in a second mold, and molding a specific resin in the second mold to form the first lid portion 221 and the outer tube portion 210.

[0046] On the other hand, the insert molding method typically involves placing the second lid portion 222 and inner plug portion 230, which have been manufactured in advance, in a mold, and molding a thermoplastic resin in the mold to form the first lid portion 221 and the outer tube portion 210. Alternatively, the insert molding method may involve placing the first lid portion 221 and outer tube portion 210, which have been manufactured in advance, in a mold, and molding a specific resin in the mold to form the second lid portion 222 and the inner plug portion 230.

[0047] <Resin Description> The specific resin described as a material for the container body and cap of the above-mentioned container represents a resin containing an alicyclic structure-containing polymer. An alicyclic structure-containing polymer contains a cyclic structure in its molecule. Typically, an alicyclic structure-containing polymer has an alicyclic structure in the repeating unit of the polymer. An alicyclic structure-containing polymer may be a homopolymer or a copolymer. An alicyclic structure-containing polymer may be a polymer having an alicyclic structure in the main chain, a polymer having an alicyclic structure in the side chain, a polymer having alicyclic structures in the main chain and the side chain, or a mixture of two or more of these in any ratio. From the viewpoint of mechanical strength and heat resistance, a polymer having an alicyclic structure in the main chain is preferred as the alicyclic structure-containing polymer.

[0048] Examples of the alicyclic structure include saturated alicyclic hydrocarbon (cycloalkane) structures, unsaturated alicyclic hydrocarbon (cycloalkene, cycloalkyne) structures, etc. Among these, from the viewpoints of mechanical strength and heat resistance, cycloalkane structures and cycloalkene structures are preferred, and cycloalkane structures are particularly preferred.

[0049] The number of carbon atoms constituting the alicyclic structure is preferably 4 or more, more preferably 5 or more, and preferably 30 or less, more preferably 20 or less, and particularly preferably 15 or less, per alicyclic structure. When the number of carbon atoms constituting the alicyclic structure is within the above range, the mechanical strength, heat resistance, and moldability are well balanced.

[0050] In the alicyclic structure-containing polymer, the proportion of repeating units having an alicyclic structure to all repeating units is preferably 55% by weight or more, more preferably 70% by weight or more, and even more preferably 90% by weight or more. When the proportion of repeating units having an alicyclic structure to all repeating units is within this range, transparency and heat resistance are good.

[0051] Examples of polymers containing an alicyclic structure include norbornene polymers; monocyclic alicyclic structure-containing polymers, cyclic conjugated diene polymers, vinyl alicyclic hydrocarbon polymers, and hydrogenated vinyl aromatic hydrocarbon polymers. Among these, one or more selected from the group consisting of norbornene polymers, vinyl alicyclic hydrocarbon polymers and hydrogenated vinyl aromatic hydrocarbon polymers are more preferred due to their excellent transparency. Furthermore, norbornene polymers and vinyl alicyclic hydrocarbon polymers and hydrogenated vinyl aromatic hydrocarbon polymers are even more preferred. Of these, norbornene polymers are particularly preferred.

[0052] Examples of norbornene-based polymers include ring-opening polymers of monomers having a norbornene structure and their hydrogenated products; and addition polymers of monomers having a norbornene structure and their hydrogenated products. Examples of ring-opening polymers of monomers having a norbornene structure include ring-opening homopolymers of one type of monomer having a norbornene structure, ring-opening copolymers of two or more types of monomers having a norbornene structure, and ring-opening copolymers of a monomer having a norbornene structure and any monomer copolymerizable therewith. Examples of addition polymers of monomers having a norbornene structure include addition homopolymers of one type of monomer having a norbornene structure, addition copolymers of two or more types of monomers having a norbornene structure, and addition copolymers of a monomer having a norbornene structure and any monomer copolymerizable therewith. Among these, preferred are hydrogenated ring-opening polymers of monomers having a norbornene structure, addition copolymers of monomers having a norbornene structure and α-olefins, and hydrogenated addition copolymers of monomers having a norbornene structure and α-olefins; and more preferred are hydrogenated ring-opening copolymers of two or more monomers having a norbornene structure, addition copolymers of monomers having a norbornene structure and α-olefins, and hydrogenated addition copolymers of monomers having a norbornene structure and α-olefins.

[0053] Examples of monomers having a norbornene structure include bicyclo[2.2.1]hept-2-ene (common name: norbornene), tricyclo[4.3.0.1 2,5 ]Deca-3,7-diene (common name: dicyclopentadiene), 7,8-benzotricyclo[4.3.0.1 2,5 ]dec-3-ene (common name: methanotetrahydrofluorene), tetracyclo[4.4.0.1 2,5 .1 7,10 ]dodec-3-ene (trivial name: tetracyclododecene) and derivatives of these compounds (for example, those having a substituent on the ring). Examples of the substituent include an alkyl group, an alkylene group, and a polar group. These substituents may be the same or different, and a plurality of them may be bonded to the ring. The monomer having a norbornene structure may be used alone or in combination of two or more kinds in any ratio.

[0054] Examples of the polar group include a heteroatom or an atomic group having a heteroatom. Examples of the heteroatom include an oxygen atom, a nitrogen atom, a sulfur atom, a silicon atom, and a halogen atom. Specific examples of the polar group include a carboxyl group, a carbonyloxycarbonyl group, an epoxy group, a hydroxyl group, an oxy group, an ester group, a silanol group, a silyl group, an amino group, a nitrile group, and a sulfonic acid group. Among these, a monomer having a norbornene structure that does not contain a polar group is preferred.

[0055] Examples of monomers capable of ring-opening copolymerization with a monomer having a norbornene structure include monocyclic olefins such as cyclohexene, cycloheptene, and cyclooctene, and derivatives thereof; cyclic conjugated dienes such as cyclohexadiene and cycloheptadiene, and derivatives thereof; etc. One type of monomer capable of ring-opening copolymerization with a monomer having a norbornene structure may be used alone, or two or more types may be used in combination at any ratio.

[0056] A ring-opening polymer of a monomer having a norbornene structure can be produced, for example, by polymerizing or copolymerizing the monomer in the presence of a ring-opening polymerization catalyst.

[0057] In the addition copolymer of a monomer having a norbornene structure and an α-olefin, examples of the α-olefin include α-olefins having 2 to 20 carbon atoms, such as ethylene, propylene, and 1-butene, and derivatives thereof. Among these, ethylene is preferred. One type of α-olefin may be used alone, or two or more types may be used in combination at any ratio.

[0058] An addition polymer of a monomer having a norbornene structure can be produced, for example, by polymerizing or copolymerizing the monomer in the presence of an addition polymerization catalyst.

[0059] The hydrogenated products of the ring-opening polymer and the addition polymer described above can be produced, for example, by hydrogenating the carbon-carbon unsaturated bonds, preferably to 90% or more, in a solution of the ring-opening polymer and the addition polymer in the presence of a hydrogenation catalyst containing a transition metal such as nickel or palladium.

[0060] Examples of trade names of norbornene-based polymers include "ZEONOR" and "ZEONEX" manufactured by Zeon Corporation; "ARTON" manufactured by JSR Corporation; and "APEL" manufactured by Mitsui Chemicals, Inc.

[0061] Examples of vinyl alicyclic hydrocarbon polymers include polymers of vinyl alicyclic hydrocarbon monomers such as vinylcyclohexene and vinylcyclohexane, and hydrogenated products thereof; and hydrogenated products of aromatic ring moieties of polymers of vinyl aromatic monomers. Furthermore, the polymer of a vinyl alicyclic hydrocarbon monomer may be a copolymer of a vinyl alicyclic hydrocarbon monomer and any monomer copolymerizable with the vinyl alicyclic hydrocarbon monomer. Furthermore, the polymer of a vinyl aromatic monomer may be a copolymer of a vinyl aromatic monomer and any monomer copolymerizable with the vinyl aromatic monomer. Examples of the copolymers include random copolymers and block copolymers. Examples of block copolymers include diblock copolymers, triblock copolymers, or higher multiblock copolymers; as well as gradient block copolymers.

[0062] The vinyl alicyclic hydrocarbon polymer is preferably a hydrogenated vinyl aromatic hydrocarbon polymer. The vinyl aromatic hydrocarbon polymer refers to a polymer containing a repeating unit [I] derived from an aromatic vinyl compound. The repeating unit derived from an aromatic vinyl compound refers to a repeating unit having a structure obtained by polymerizing an aromatic vinyl compound. However, the polymer and its constituent units are not limited by their production method.

[0063] Examples of aromatic vinyl compounds corresponding to the repeating unit [I] include styrene; styrenes having an alkyl group having 1 to 6 carbon atoms as a substituent, such as α-methylstyrene, 2-methylstyrene, 3-methylstyrene, 4-methylstyrene, 2,4-dimethylstyrene, 2,4-diisopropylstyrene, 4-t-butylstyrene, and 5-t-butyl-2-methylstyrene; styrenes having a halogen atom as a substituent, such as 4-chlorostyrene, dichlorostyrene, and 4-monofluorostyrene; styrenes having an alkoxy group having 1 to 6 carbon atoms as a substituent, such as 4-methoxystyrene; styrenes having an aryl group as a substituent, such as 4-phenylstyrene; and vinylnaphthalenes such as 1-vinylnaphthalene and 2-vinylnaphthalene. These may be used alone, or two or more may be combined in any ratio. Among these, aromatic vinyl compounds not containing a polar group, such as styrene and styrenes having an alkyl group having 1 to 6 carbon atoms as a substituent, are preferred because they have low hygroscopicity, and styrene is particularly preferred because of its industrial availability.

[0064] The polymer containing the repeating unit [I] derived from an aromatic vinyl compound is preferably a specific block copolymer [D]. The block copolymer [D] is a block copolymer consisting of a polymer block [A] and a polymer block [B] or a polymer block [C]. The polymer block [A] is a polymer block mainly composed of the repeating unit [I] derived from an aromatic vinyl compound. The polymer block [B] is a polymer block mainly composed of the repeating unit [I] derived from an aromatic vinyl compound and the repeating unit [II] derived from a linear conjugated diene compound. The polymer block [C] is a polymer block mainly composed of the repeating unit [II] derived from a linear conjugated diene compound. Here, the "main component" refers to a component that accounts for 50% by weight or more of the polymer block. The proportion of the main component in the polymer block is preferably 80% by weight or more, more preferably 90% by weight or more, and even more preferably 100% by weight. The repeating unit derived from a linear conjugated diene compound refers to a repeating unit having a structure obtained by polymerizing a linear conjugated diene compound.

[0065] Examples of the chain conjugated diene compound corresponding to the repeating unit [II] include 1,3-butadiene, isoprene, 2,3-dimethyl-1,3-butadiene, and 1,3-pentadiene. These may be used alone or in combination of two or more in any ratio. The chain conjugated diene compound may be linear or branched.

[0066] The hydrogenated vinyl aromatic hydrocarbon polymer is a hydrogenated polymer containing a repeating unit [I] derived from an aromatic vinyl compound. The hydrogenated polymer containing a repeating unit [I] derived from an aromatic vinyl compound is preferably a specific hydrogenated block copolymer [E]. The hydrogenated block copolymer [E] is a hydrogenated block copolymer [D] described above.

[0067] A hydrogenated vinyl aromatic hydrocarbon polymer is a substance obtained by hydrogenating the unsaturated bonds of a vinyl aromatic hydrocarbon polymer. Here, the unsaturated bonds of the vinyl aromatic hydrocarbon polymer to be hydrogenated include both carbon-carbon unsaturated bonds in the main chain and side chains of the polymer and carbon-carbon unsaturated bonds in the aromatic rings.

[0068] The hydrogenated product can be produced, for example, by hydrogenating the unsaturated bonds of the polymer, preferably to 90% or more, in a solution of the vinyl aromatic hydrocarbon polymer in the presence of a hydrogenation catalyst containing a transition metal such as nickel or palladium.

[0069] The specific resin may contain one type of alicyclic structure-containing polymer, or two or more types of polymers.

[0070] The weight-average molecular weight Mw of the alicyclic structure-containing polymer contained in the specific resin is preferably 10,000 or more, more preferably 15,000 or more, particularly preferably 20,000 or more, and is preferably 100,000 or less, more preferably 80,000 or less, particularly preferably 50,000 or less. When the weight-average molecular weight is within this range, the mechanical strength and moldability of the resin are well balanced.

[0071] The molecular weight distribution (Mw / Mn) of the alicyclic structure-containing polymer contained in the specific resin is preferably 1.2 or more, more preferably 1.5 or more, particularly preferably 1.8 or more, and preferably 3.5 or less, more preferably 3.0 or less, particularly preferably 2.7 or less. Here, Mn represents the number-average molecular weight. When the molecular weight distribution is at or above the lower limit of the above range, the productivity of the polymer can be increased and production costs can be reduced. On the other hand, when it is at or below the upper limit, the amount of low-molecular-weight components is reduced. As a result, relaxation of the resin when exposed to high temperatures can be suppressed, and the stability of members containing the resin can be improved.

[0072] The weight-average molecular weight (Mw) and number-average molecular weight (Mn) can be measured using gel permeation chromatography (GPC). Solvents used in GPC include cyclohexane, toluene, and tetrahydrofuran. When using GPC, the weight-average molecular weight is measured as a relative molecular weight, for example, in terms of polyisoprene or polystyrene.

[0073] The weight proportion (content) of the alicyclic structure-containing polymer in the specific resin is preferably 50% by weight or more, more preferably 60% by weight or more, even more preferably 70% by weight or more, still more preferably 80% by weight or more, and particularly preferably 90% by weight or more. The upper limit is usually 100% by weight or less, and may be 99% by weight or less.

[0074] The specific resin may contain other optional components in combination with the alicyclic structure-containing polymer, as long as the effects of the present invention are not significantly impaired. Examples of the optional components include polymers other than the alicyclic structure-containing polymer; colorants such as pigments and dyes; fluorescent brighteners; dispersants; heat stabilizers; light stabilizers; UV absorbers; antistatic agents; antioxidants; and lubricants. One type of optional component may be used alone, or two or more types may be used in combination in any ratio.

[0075] The specific resin preferably has a glass transition temperature Tg within a specific range. The range of the glass transition temperature Tg is preferably 60°C or higher, more preferably 100°C or higher, and even more preferably 110°C or higher, and is preferably 200°C or lower, more preferably 190°C or lower, and even more preferably 180°C or lower.

[0076] The glass transition temperature of a resin can be measured by differential scanning calorimetry based on JIS K 7121. This measurement can be performed by raising the temperature of a sample from room temperature to 200°C at 20°C / min, then cooling it to 40°C at 20°C / min, and then raising the temperature from 40°C to 200°C at 10°C / min.

[0077] <Application> There are no particular limitations on the contents stored in the above-described container. From the perspective of utilizing the advantage of being able to suppress adsorption to the inner stopper portion of the cap, preferred contents include proteins, nucleic acids, preparations using these, and compositions containing these. Furthermore, from the perspective of utilizing the advantage of being able to suppress the formation of gaps between the container body and the inner stopper portion of the cap, contents that are prone to change through minute gaps are preferred. For example, since liquids such as solvents or dispersion media are prone to change in volume due to evaporation, contents containing these liquids are preferred. For example, the internal reaction may be a liquid content containing water. Therefore, from the perspective of utilizing the above-described advantages, the container, container body, and cap according to the above-described embodiment may be used to store contents such as pharmaceuticals, foods, cosmetics, biochemical reagents, etc. [Explanation of symbols]

[0078] 10 containers 100 container body 110 Base 111 Flange 112 Gripping part 113 Groove 114 Ring section 120 Mouth 121 Aperture 122 Outer surface 123 threads 124 Inner surface 125 inner edge 126 Contact site 200 caps 210 Outer cylinder 211 Inner surface 212 threads 213 Outer surface 214 Groove 220 Lid 221 First lid part 221E Inner edge 222 Second lid part 222E outer edge 223 Overhang 224 Convex 225 recess 226 Recess 230 Internal plug part 231 Outer surface 231E End of the lid 232 Slope section 233 Hollow part 240 Gap

Claims

1. an outer tubular portion having an inner circumferential surface on which a thread is formed; a lid portion formed at one end of the outer cylinder portion; a cap including an inner plug portion connected to the lid portion and formed of a resin containing an alicyclic structure-containing polymer, within the outer cylindrical portion; the inner plug portion has an outer circumferential surface formed with a gap between it and the outer cylindrical portion; A cap, wherein the outer peripheral surface of the inner plug portion includes a surface portion formed to have a larger diameter as it approaches the lid portion.

2. The cap according to claim 1 , wherein the surface portion is formed continuously from an end portion of the outer peripheral surface of the inner plug portion on the lid portion side.

3. The cap according to claim 1 , wherein the entire outer peripheral surface of the inner plug portion forms the surface portion.

4. The cap according to claim 1 , wherein the inner plug portion has a hollow portion extending in the axial direction of the cap.

5. The lid portion includes a first lid portion connected to the outer cylinder portion, and a second lid portion formed inside the first lid portion and connected to the inner plug portion; The cap according to claim 1 , wherein the second lid portion comprises a resin containing an alicyclic structure-containing polymer.

6. A protruding portion protruding radially inward is formed at one or more axial portions of an inner edge portion of the first lid portion, A recessed portion recessed radially inward is formed in one or more axial portions of an outer edge portion of the second cover portion, The cap according to claim 5 , wherein the protruding portion of the first lid portion and the recessed portion of the second lid portion are engaged with each other.

7. A convex portion protruding radially inward is formed at one or more circumferential portions of an inner edge portion of the first lid portion, A recess recessed radially inward is formed in one or more circumferential portions of an outer edge of the second lid portion, The cap according to claim 5 , wherein the protrusion of the first lid portion and the recess of the second lid portion are engaged with each other.

8. A cap according to any one of claims 1 to 7; a container body having a mouth formed so that the cap can be attached.

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