Cap and container

A cap configured to be detachably attached to a mouth portion of a container body having a containment space for contents and close the mouth portion, includes: a transparent or semitransparent topped tubular outer lid portion; and a topped tubular inner lid portion located in close contact with an inner side of the outer lid portion so as to be relatively non-rotatable. A retaining protrusion having an inclined surface that is inclined inward in a downward direction and extends to a lower end of the outer lid portion is provided on an inner peripheral surface of the outer lid portion. The retaining protrusion engages with a retaining depression provided on an outer peripheral surface of the inner lid portion, to suppress separation between the outer lid portion and the inner lid portion.

TECHNICAL FIELD

The present disclosure relates to a cap of a laminate structure including a transparent or semitransparent topped (i.e. having a top) tubular outer lid portion and a topped tubular inner lid portion located in close contact with the inner side of the outer lid portion, and a container including the cap.

BACKGROUND

Conventionally known containers for containing contents such as cosmetic cream have a structure including: a bottomed tubular container body that is open upward and has an external thread on its outer periphery: and a cap that is open downward and closes the container body.

For such a container, the following technique is proposed: The cap has a laminate structure (double structure) including an inner lid portion and an outer lid portion, a metal film (metallic luster layer) is provided on the outer surface of the inner lid portion, and the outer lid portion is made of a transparent material (see JP 2005-335799 A (PTL 1)). By allowing the metallic luster layer of the inner lid portion to be seen through the outer lid portion, luxurious appearance can be achieved.

CITATION LIST

Patent Literature

SUMMARY

Technical Problem

However, as a result of providing the metallic luster layer on the outer surface of the inner lid portion as in the foregoing cap, the contact (adhesion) strength between the inner lid portion and the outer lid portion decreases. This incurs the risk that the outer lid portion is misaligned with respect to the inner lid portion and lifted off the inner lid portion, or the outer lid portion falls off the inner lid portion due to drop impact or the like. Even in the case where the metallic luster layer is not provided on the outer surface of the inner lid portion, depending on the combination between the material of the inner lid portion and the material of the outer lid portion, the contact strength decreases, and such lifting or falling may occur. In the case where a projection (protrusion) and a groove (depression) for fitting are provided at a noticeable position between the inner lid portion and the outer lid portion in order to prevent such lifting or falling, there is the possibility that the projection and the groove can be seen through the outer lid portion and the appearance design degrades.

It could therefore be helpful to provide a cap and a container that can enhance the contact strength between an inner lid portion and an outer lid portion without degradation in appearance design.

Solution to Problem

A cap according to the present disclosure is a cap configured to be detachably attached to a mouth portion of a container body having a containment space for contents and close the mouth portion, the cap comprising: a topped tubular outer lid portion that is transparent or semitransparent; and a topped tubular inner lid portion located in close contact with an inner side of the outer lid portion so as to be relatively non-rotatable, wherein a retaining protrusion is provided on an inner peripheral surface of the outer lid portion, the retaining protrusion having an inclined surface that is inclined inward in a downward direction and extends to a lower end of the outer lid portion, and the retaining protrusion engages with a retaining depression provided on an outer peripheral surface of the inner lid portion, to suppress separation between the outer lid portion and the inner lid portion.

Preferably, in the cap according to the present disclosure, a metallic luster layer is formed on an outer surface of the inner lid portion.

Preferably, the cap according to the present disclosure comprises a topped tubular attachment portion fixed to and held by an inner side of the inner lid portion, and configured to be attached to the mouth portion of the container body.

Preferably, in the cap according to the present disclosure, an internal thread portion is provided on an inner peripheral surface of the attachment portion, the internal thread portion being configured to engage with an external thread portion provided on an outer peripheral surface of the mouth portion of the container body.

Preferably, in the cap according to the present disclosure, the outer peripheral surface of the inner lid portion has a polygonal shape in a plan view.

Preferably, in the cap according to the present disclosure, a knurling having irregularities repeated in a circumferential direction is provided on the outer peripheral surface of the inner lid portion.

Preferably, in the cap according to the present disclosure, satin-like irregularities are provided on the outer peripheral surface of the inner lid portion.

Preferably, in the cap according to the present disclosure, a depression or a protrusion for suppressing rotation of the inner lid portion relative to the outer lid portion is provided on part of the outer peripheral surface of the inner lid portion in a circumferential direction.

Preferably, in the cap according to the present disclosure, the outer peripheral surface of the inner lid portion has an elliptical shape in a plan view.

Preferably, a container according to the present disclosure comprises: a bottomed tubular container body having a containment space for contents; and the above-described cap attached to a mouth portion of the container body.

Advantageous Effect

It is thus possible to provide a cap and a container that can enhance the contact strength between an inner lid portion and an outer lid portion without degradation in appearance design.

DETAILED DESCRIPTION

One of the disclosed embodiments will be described in detail below, with reference to the drawings. Herein, the upper side is the side on which a cap20is located with respect to a container body10, and the lower side is the opposite side (i.e. the side on which the container body10is located with respect to the cap20).

As illustrated inFIG.1, a container1according to this embodiment includes the bottomed tubular container body10and the topped tubular cap20detachably attached to the container body10. The cap20is detachably attached to a mouth portion11of the container body10, and closes the mouth portion11.

The container body10includes the tubular mouth portion11having an axis O as a central axis, a barrel portion12located below and connected to the mouth portion11, and a bottom portion13closing the lower end of the barrel portion12. A containment space S for containing contents is formed inside the container body10. The container body10may have a structure in which the contents are directly charged into the containment space S, or a structure in which a bottomed tubular inner container or the like containing the contents beforehand is placed in the containment space S in a replaceable manner.

The cap20includes a transparent or semitransparent outer lid portion30and a topped tubular inner lid portion40located in close contact with the inner side of the outer lid portion30so as to be relatively non-rotatable. Although the cap20in this example has a triple structure in which an attachment portion50is fixed to and held by the inner side of the inner lid portion40, the present disclosure is not limited to such, and the cap20may have a double structure composed only of the outer lid portion30and the inner lid portion40, or a quadruple or higher laminate structure. The material of each of the outer lid portion30, the inner lid portion40, and the attachment portion50is not limited, and may be a synthetic resin.

The outer lid portion30may be partially non-transparent as long as it is transparent or semitransparent as a whole. For example, the outer lid portion30may be made of a highly transparent resin such as polyester resin (PETG, PCTA, PCTG, PCT, etc.), SAN (styrene acrylonitrile copolymer), PMMA (methyl polyacrylate), or ionomer. The inner lid portion40may be made of a non-transparent material, or may be transparent or semitransparent. For example, the inner lid portion40may be made of a resin having relatively high heat resistance such as PC (polycarbonate).

The outer lid portion30has a tubular (cylindrical in this example) outer peripheral wall31and an outer top wall32connected to the upper end of the outer peripheral wall31.

FIG.2is a partially enlarged sectional view of the outer lid portion30and the inner lid portion40in the cap20inFIG.1. As illustrated inFIG.2, a retaining protrusion33is provided at the lower end of the inner peripheral surface of the outer peripheral wall31in the outer lid portion30. The retaining protrusion33has an inclined surface34that is inclined inward (i.e. toward the axis O) in the downward direction and extends to the lower end of the outer lid portion30(the lower end of the outer peripheral wall31). The inclined surface34is not limited to a flat surface as in this example, and may be a curved surface. The upper end of the flat surface is preferably connected smoothly to the inner peripheral surface of the outer peripheral wall31. The retaining protrusion33may be provided on the whole of the outer peripheral wall31in the circumferential direction, or provided on only part of the outer peripheral wall31in the circumferential direction. In this example, the retaining protrusion33is provided on only part of the outer peripheral wall31in the circumferential direction, and the retaining protrusion33and the below-described retaining depression43also function as a rotation suppression portion that suppresses the rotation of the outer lid portion30relative to the inner lid portion40.

The inner lid portion40has a tubular (cylindrical in this example) inner peripheral wall41and a top wall42connected to the upper end of the inner peripheral wall41. The retaining depression of the shape corresponding to the retaining protrusion33is formed on the outer peripheral surface of the inner peripheral wall41in the inner lid portion40. The retaining depression43has an inclined surface44that is inclined inward (i.e. toward the axis O) in the downward direction and extends to the lower end of the inner lid portion40(the lower end of the inner peripheral wall41). The shape of the retaining depression43matches the shape of the retaining protrusion33, and the inclined surface44is in close contact with the inclined surface34of the retaining protrusion33.

The retaining protrusion33and the retaining depression43function as a separation suppression portion that suppresses separation between the outer lid portion30and the inner lid portion40. In detail, the retaining protrusion33of the outer lid portion30is fitted into and undercut-engages with the retaining depression43of the inner lid portion40, thus suppressing separation between the outer lid portion30and the inner lid portion40in the axial direction (i.e. the direction along the axis O). By providing such a separation suppression portion, the outer lid portion30can be prevented from lifting or falling off the inner lid portion40.

The attachment portion50has a tubular (cylindrical in this example) attachment peripheral wall51and a closure wall52connected to the upper end of the attachment peripheral wall51. Although a space is formed between the closure wall52and the top wall42of the inner lid portion40in this example, the present disclosure is not limited to such, and the closure wall52and the top wall42may be in close contact with each other.

An engaging protrusion51ais provided on the outer peripheral surface of the attachment peripheral wall51. As a result of the engaging protrusion51aengaging with an engaged protrusion41aprovided on the inner peripheral surface of the inner peripheral wall41in the inner lid portion40, the attachment portion50is engaged with and held by the inner side of the inner lid portion40.

An internal thread portion51bis provided on the inner peripheral surface of the attachment peripheral wall51. An external thread portion11ais provided on the outer peripheral surface of the mouth portion11in the container body10. As a result of the internal thread portion51bengaging with the external thread portion11a, the cap20is detachably attached to the container body10.

A disk-shaped packing60is provided on the lower surface of the closure wall52. By sandwiching the packing60between the lower surface of the closure wall52and the upper end surface of the mouth portion11as illustrated inFIG.1, the sealing property of the cap20that closes the mouth portion11can be enhanced.

As described above, the container1and the cap20according to this embodiment include the retaining protrusion33and the retaining depression43as the separation suppression portion, so that the outer lid portion30can be prevented from lifting of falling off the inner lid portion40. Moreover, since the retaining protrusion33has the inclined surface34that is inclined inward in the downward direction and extends to the lower end of the outer lid portion30, even if the retaining protrusion33and the retaining depression43can be seen through the outer lid portion30, the retaining protrusion33and the retaining depression43are unnoticeable. Hence, degradation in appearance design can be prevented.

Particularly in the case of performing insert molding (overmolding) whereby, using the primary-molded inner lid portion40as an insert material, the outer lid portion30is secondary-molded with a resin different form the inner lid portion40, because of no compatibility (or low compatibility) between the resin forming the inner lid portion40and the resin forming the outer lid portion30, there is the possibility of poor appearance as a result of the inner lid portion40and the outer lid portion30being not in close contact with each other. In this embodiment, by providing the retaining protrusion33and the retaining depression43as the separation suppression portion, the contact strength can be enhanced even in the case where the resin forming the inner lid portion40and the resin forming the outer lid portion30are not compatible with each other, with it being possible to improve the appearance.

For example, consider the case of enhancing the contact strength between an outer lid portion and an inner lid portion whose outer surface is subjected to aluminum vapor deposition and then coated with an acrylic resin to form a metallic luster layer, without providing the retaining protrusion33and the retaining depression43as the separation suppression portion. For this attempt, a method of enhancing the contact strength by surface-treating (e.g. frame-treating) the metallic luster layer on the outer surface of the inner lid portion before the insert molding of molding the outer lid portion using the inner lid portion as the insert material may be used. However, in the case where the metallic luster layer on the outer surface of the inner lid portion is surface-treated, the inner lid portion may deform improperly due to heat. The container1and the cap20according to this embodiment, on the other hand, include the retaining protrusion33and the retaining depression43as the separation suppression portion, so that the outer lid portion30can be prevented from lifting or falling off the inner lid portion40without performing the foregoing surface treatment. Since there is no possibility of improper deformation caused by surface treatment, appearance deterioration can be prevented.

Thus, the container1and the cap20according to this embodiment can enhance the contact strength between the inner lid portion40and the outer lid portion30without degradation in appearance design.

The rotation suppression portion for suppressing relative rotation about the axis O is provided between the outer lid portion30and the inner lid portion40. By providing the rotation suppression portion, a misalignment between the outer lid portion30and the inner lid portion40in the circumferential direction is also suppressed (i.e. the outer lid portion30and the inner lid portion40are relatively non-rotatable). Thus, separation between the outer lid portion30and the inner lid portion40can be suppressed more reliably. In this example, the retaining protrusion33and the retaining depression43are provided only on part of the circumference, and engage with each other in the circumferential direction, too. Hence, the retaining protrusion33and the retaining depression43function as the rotation suppression portion for suppressing the rotation of the outer lid portion30relative to the inner lid portion40.

The rotation suppression portion is not limited to this example. For example, any of the structures illustrated inFIGS.3A and3B,4A and4B,5A and5B,6A and6B, and7A and7Bmay be employed.

In the example illustrated inFIGS.3A and3B, the outer peripheral surface of the inner lid portion40has a polygonal shape in a plan view. The right half part of the sectional view inFIG.3Aillustrates the outer lid portion30and the inner lid portion40in the cap20. The left half part of the sectional view inFIG.3Aand the bottom view inFIG.3Billustrate only the outer lid portion30while omitting the inner lid portion40.

In this example, the outer peripheral surface of the inner peripheral wall41in the inner lid portion40is a regular hexadecagon in a plan view, and correspondingly the inner peripheral surface of the outer peripheral wall31in the outer lid portion30is a regular hexadecagon in a plan view, too. The outer peripheral surface of the inner lid portion40and the inner peripheral surface of the outer lid portion30that are polygonal in a plan view engage with each other in the circumferential direction, and therefore function as the rotation suppression portion. In the example illustrated inFIGS.3A and3B, of the 16 surfaces (sides) formed in the inner peripheral surface of the outer peripheral wall31(i.e. the 16 surfaces (sides) constituting the regular hexadecagon), a surface31awith the retaining protrusion33and a surface31b(flat surface) without the retaining protrusion33alternate with each other.

In the example illustrated inFIGS.4A and4B, a knurling41bhaving irregularities repeated in the circumferential direction is provided on the outer peripheral surface of the inner peripheral wall41in the inner lid portion40, and a knurling31cis provided on the corresponding inner peripheral surface of the outer peripheral wall31in the outer lid portion30. The knurling41bof the inner lid portion40and the knurling31cof the outer lid portion30engage with each other in the circumferential direction, and thus function as the rotation suppression portion. In this example, the retaining protrusion33of the outer lid portion30and the retaining depression43of the inner lid portion40are provided on the whole circumference.

In the example illustrated inFIGS.5A and5B, satin-like irregularities (texture) are provided on the outer peripheral surface of the inner peripheral wall41in the inner lid portion40, and also satin-like irregularities are provided on the corresponding inner peripheral surface of the outer peripheral wall31in the outer lid portion30. The satin-like irregularities of the inner lid portion40and the satin-like irregularities of the outer lid portion30engage with each other in the circumferential direction, and thus function as the rotation suppression portion. In this example, the retaining protrusion33of the outer lid portion30and the retaining depression43of the inner lid portion40are provided on part of the circumference. In detail, the retaining protrusion33and the retaining depression43are located in four positions at equal spacings in the circumferential direction. In this example, the satin-like irregularities are provided on the whole outer surface of the inner lid portion40and the whole inner surface of the outer lid portion30.

In the example illustrated inFIGS.6A and6B, a protrusion projecting radially outward is provided on part of the outer peripheral surface of the inner peripheral wall41in the inner lid portion40in the circumferential direction, and a depression31dis provided on the corresponding inner peripheral surface of the outer peripheral wall31in the outer lid portion30. The protrusion of the inner lid portion40and the depression31dof the outer lid portion30engage with each other in the circumferential direction, and thus function as the rotation suppression portion. The protrusion in this example is provided at the lower end of the inner peripheral wall41, in two circumferential positions opposite to each other with the axis O therebetween. However, the number of protrusions and the positions of the protrusions may be changed as appropriate. The depression and the protrusion may be provided respectively on the outer peripheral surface of the inner peripheral wall41and the inner peripheral surface of the outer peripheral wall31. In this example, the retaining protrusion33of the outer lid portion30and the retaining depression43of the inner lid portion40are provided on part of the circumference. In detail, the retaining protrusion33and the retaining depression43are located in four circumferential positions at equal spacings that are different from the circumferential positions of the depression31dand the protrusion forming the rotation suppression portion.

In the example illustrated inFIGS.7A and7B, the outer peripheral surface of the inner peripheral wall41in the inner lid portion40has an elliptical shape in a plan view, and correspondingly the inner peripheral surface of the outer peripheral wall31in the outer lid portion30has an elliptical shape in a plan view, too. The outer peripheral surface of the inner lid portion40and the inner peripheral surface of the outer lid portion30elliptically shaped in a plan view engage with each other in the circumferential direction, and thus function as the rotation suppression portion. In this example, the retaining protrusion33of the outer lid portion30and the retaining depression43of the inner lid portion40are provided on the whole circumference.

For example, the cap20can be formed as follows: The inner lid portion40molded by injection molding or the like beforehand is placed in a mold as an insert member, and the outer lid portion30is integrally molded (insert-molded) on the outer side of the inner lid portion40by injection molding or the like in a state of being in close contact. After this, the attachment portion50molded by injection molding or the like separately from the outer lid portion30and the inner lid portion40is attached to the inner side of the inner lid portion40. The method of forming the cap20is, however, not limited to such. In this case, before molding the outer lid portion30on the outer side of the inner lid portion40, a metallic luster layer may be optionally provided on the outer surface of the inner lid portion40. The metallic luster layer may be provided, for example, by a hot stamping method or a vacuum vapor deposition method. The metallic luster layer provided on the outer surface of the inner lid portion40can be seen through the outer lid portion30. This further enhances the luxurious appearance of the cap20. In the case where the metallic luster layer is provided on the outer surface of the inner lid portion40, the contact strength between the outer lid portion30and the inner lid portion40decreases. In this embodiment, however, the separation suppression portion (the retaining protrusion33and the retaining depression43) can suppress separation between the outer lid portion30and the inner lid portion40.

Although the presently disclosed technique has been described above based on the illustrated examples, the present disclosure is not limited to the foregoing embodiments, and changes can be made as appropriate within the scope of the claims, For example, the means of engagement between the mouth portion11of the container body10and the cap20is not limited to screw engagement, and an outward protrusion provided on the outer peripheral surface of the mouth portion11and an inward protrusion provided on the inner peripheral surface of the cap20may detachably undercut-engage with each other.

REFERENCE SIGNS LIST