US20250033842A1

US20250033842A1 - Closure for a spout of a thin-walled package

Info

Publication number: US20250033842A1
Application number: US18/716,364
Authority: US
Inventors: Alberto BUZZI
Original assignee: Guala Pack SpA
Current assignee: Guala Pack SpA
Priority date: 2022-02-17
Filing date: 2023-02-17
Publication date: 2025-01-30
Also published as: EP4479319A1; CR20240247A; CL2024001802A1; MX2024007165A; WO2023156950A1; IT202200002978A1

Abstract

A closure assembly for a package with a flexible thin-walled bag that has a spout unit having a spout having an inner surface is provided. The spout unit has at least one spout cam portion made on the inner surface. A closure applicable to the spout unit has a cap unit having a cap engageable with the spout and extending along a cap axis. The cap has a cap base. The cap unit has at least one cap cam portion that extends inwards from the cap base and that is at least partly complementary to the at least one spout cam portion. In a disengagement configuration, by rotating the cap with respect to the spout about the cap axis, an interaction between the at least one cap cam portion and the at least one spout cam portion causes the cap to rise axially with respect to the spout.

Description

The present invention is in the field of thin-walled packages fitted with a spout, usually referred to as a “pouch”. In particular, the present invention refers to a closure assembly for a spout of said package.
Said packages are primarily used to contain fruit juices, yogurt, fruit puree, energy drinks, and similar products for children. These packages have become very popular, due to their compact size, great practicality of use, and playful aspect linked to the use of the spout, which attracts the attention of children. Several hundred million units are produced and sold every year.
Typically, closures for spouts, made of plastics material, consist of a cap and a spout which are respectively threaded. The cap screws onto the spout to close the package and prevent the liquid from leaking out.
Recently, the research and development efforts of manufacturing companies have focused on making lightweight closure assemblies, the production of which requires less plastics material.
It is the object of the present invention to make a closure assembly for a spout of a thin-walled package that meets the aforesaid requirements, i.e., a closure assembly that is lightweight and is produced using less plastics material, while still ensuring a high degree of convenience and significant comfort for the user. This object is achieved by a closure assembly
according to claim 1. The claims dependent thereon describe preferred embodiment variants involving further advantageous aspects.

The features and advantages of the closure assembly according to this invention will become apparent from the following description, given by way of non-limiting example according to the figures in the accompanying drawings, wherein:

FIG. 1 a to 1 e are five perspective views of a package in a preferred embodiment, in different configurations;

FIG. 2 a to 2 e are five sectional views of the package in FIG. 1 a to 1 e;

FIG. 3 a to 3 d are four front views of a closure assembly of the package in a preferred embodiment, in different configurations;

FIGS. 4 a to 4 d and 5 a to 5 d are sectional views of the closure assembly of FIG. 3 a to 3 d in two different sectional planes;

FIG. 6 is a front view of the closure assembly in a second preferred embodiment;

FIGS. 7 a and 7 b are two enlargements of a guarantee seal of the closure assembly in two different embodiments;

FIGS. 8 and 9 are two front sectional views of the closure assembly in two different embodiments;

FIGS. 8 a and 9 a are two enlargements of the box V-V and VI-VI of FIGS. 8 and 9 ;

FIG. 10 is an enlargement of the box VII-VII of FIG. 8 ;

FIG. 11 is a front sectional view of a spout unit of the closure assembly according to a preferred embodiment;

FIGS. 12 and 13 are two front views of a closure of the closure assembly, according to two different embodiments;

FIG. 14 to 18 are perspective views of the closure assembly in further embodiments.

In reference to the figures in the attached drawings, reference sign 1 has been used to indicate a closure assembly of a thin-walled package, usually referred to as a “pouch”. Said package comprises a bag for containing the product.
According to a preferred embodiment, the package comprises a front wall and a rear wall which face each other and are formed by a flexible, monolayer or multilayer film. The walls are welded together along the side edges or, in an embodiment variant, sides are provided which are made of flexible film and welded to the walls.
The closure assembly 1 comprises a spout unit 2 which extends along a spout axis X-X and is preferably made of plastics material in a single piece, by injection molding.
According to a preferred embodiment, the spout unit 2 has an internal spout duct 12 extending along the spout axis X-X from a lower end 14 a, intended to be contained in the bag, to an upper end 14 b in which a mouth 16 for dispensing the product is found.
The spout unit 2 comprises a connection portion 20, referred to as a “weld boat,” which is suitable for being sealingly applied to the bag, preferably between the top edges of the walls, for example by welding.
According to a preferred embodiment, the spout unit 2 comprises a lower plate 22 orthogonal to the spout axis X-X.
According to a preferred embodiment, the connection portion 20 is axially delimited at the top by this lower plate 22.
According to a preferred embodiment, the spout unit 2 further comprises an upper plate 24, also orthogonal to the spout axis X-X, preferably axially spaced from the lower plate 22.
Preferably, the upper plate 24 has two opposing straight edges 23′, 23″ connected by two leading edges 27′, 27″ which are, for example, arched. Preferably, the plate 22 also comprises said straight edges 23′, 23″ and said leading edges 27′, 27″.
The spout unit 2 comprises a spout 10. Preferably, the spout 10 extends axially from the upper plate 24 and ends with the mouth 16.
In a preferred embodiment, the spout unit 2 further comprises an engagement plate 26, preferably orthogonal to the spout axis X-X and projecting radially outward from the outer side surface of the spout 10. The projection of the shape of the engagement plate 26 along the spout axis X-X onto the second plate 24 is entirely contained within said second plate 24, so as not to interfere with the movement of the packages along the filling lines.
According to a preferred embodiment, a ring seat 100 is formed between the engagement plate 26 and the second plate 24.
The spout 10 comprises an inner surface 13, in particular which radially delimits the spout duct 12. Furthermore, the spout 10 comprises an outer surface 15 facing the external environment.
According to the invention, the spout unit 2 also comprises at least one spout cam portion 25 made on the inner surface 13. Preferably, said spout cam portion 25 has extension of at least a quarter of the circumference.
It is noted that the definition of “spout cam portion” does not include the profile of a thread. Indeed, the present invention intends to avoid the use of a thread on the spout, in order to lighten it.
A thread consists of a protrusion (thread) which winds continuously or continuously in sections, helically, on the outer surface of a cylindrical or conical element (screw) or on the inner surface of a similar element (nut screw), extending axially along them. In other words, it is a protruding helical rib which allows the parts to be screwed together.
The cam, on the other hand, is an element that extends circumferentially, generally eccentrically, and is suitably shaped.
Preferably, the spout cam portion 25 is made protruding radially from the inner surface 13.
According to a preferred embodiment, the spout cam portion 25 is made in an upper portion of the spout 10, i.e. close to the mouth 16.
Preferably, the spout cam portion 25 defines an upper cam surface 250, inclined with respect to the spout axis X-X. Preferably, the upper cam surface 250 has an extension equal to at least one quarter of the circumference.
According to a preferred embodiment, the upper cam surface 250 of the spout cam portion 25 has an arcuate shape with a lowered center so as to define two opposite slopes. Preferably, the center is lowered with respect to the mouth 16 and a first and second end are close to such mouth 16. Preferably, the spout cam portion 25 has an extension equal to half of the circumference.
In a preferred embodiment, the upper cam surface 250 has a flattened center and/or the arc does not necessarily have a constant radius.
According to a further embodiment (not shown), the upper cam surface 250 has a single inclined surface, i.e. one end is proximal with respect to the mouth 16 and one end is lowered with respect to the mouth 16.
According to a preferred embodiment, the spout unit 2 comprises a plurality of spout cam portions 25, preferably comprises two spout cam portions 25, diametrically opposite and arranged symmetrically with respect to the spout axis X-X.
According to a preferred embodiment, the spout cam portions 25 have an extension equal to half of the circumference and the ends of one are close to the ends of the other, preferably in contact so as to form a single spout cam portion 25 in which high sections 162, proximal to the mouth 16, and low sections 164, distal to the mouth 16, alternate.
According to a preferred embodiment, the spout 10, externally, in the vicinity of the mouth 16, comprises an enlarged spout lip 28. Preferably, below said spout lip 28, the spout 10 comprises a retractable spout backing 29, so as to further accentuate said spout lip 28. In other words, the spout 10, at the spout backing 29, is thinned.
According to the invention, the closure assembly 1 further comprises a closure 3 applicable to the spout unit 2 and comprises a cap unit 4.
According to a first embodiment, the closure 3 comprises a handle 40, preferably made in one piece with the cap unit 4.
According to a second embodiment, the closure 3 comprises an over-cap 5, preferably made separately from the cap unit 4 and subsequently joined to it.
The cap unit 4 comprises a cap 30, having a central cap axis Y-Y and comprising an annular cap wall 31 and a cap base 32 which closes the cap wall 31 at one end.
Preferably, the cap wall 31 comprises a lower edge 33. Preferably, the lower edge 33 is positioned at the end of the cap wall 31 opposite to that of the cap base 32.
The cap unit 4 further comprises a guarantee seal 34 comprising a guarantee ring 36, a guarantee band 38, and a plurality of breakable bridges 60 joining the guarantee ring 36 to the guarantee band 38 and the guarantee band 38 to the cap wall 31, preferably to the lower edge 33.
According to a preferred embodiment, the guarantee band 38, which extends between an initial portion 37 and an end portion 39, is wound about the cap axis Y-Y in a circumferential pattern, whereby, in an unbroken seal configuration, the initial 37 is portion circumferentially opposite the end portion 39 and spaced apart therefrom.
The guarantee band 38 also overlaps the guarantee ring 36, from which it is separated axially by a first separation line 62, along which some bridges 60 are arranged. The cap wall 31 in turn axially overlaps the guarantee band 38, from which it is separated axially by a second separation line 64, along which some bridges 60 are arranged.
According to a preferred embodiment, the guarantee seal 34 further comprises a first attachment portion 66, which is more resistant than the breakable bridges 60 and joins the guarantee band 38, and in particular the initial portion 37 thereof, to the guarantee ring 36. The guarantee seal 34 further comprises a second attachment portion 68, which is more resistant than the bridges 60 and joins the guarantee band 38, and in particular the end portion 39 thereof, to the cap wall 31, preferably to the lower edge 33.
Moreover, according to a preferred embodiment, the bridges 60 are configured to preferentially break at the attachment zone with the guarantee band 38, whereby any residual protrusions remaining after the first opening remain attached to the guarantee ring 36 or to the cap wall 31, leaving the guarantee band 38 free of protrusions.
For this purpose, the bridges 60 have a cross section with a decreasing resistance from the guarantee band 38 toward the guarantee ring 36 or toward the cap wall 31, whereby, at the attachment zone with the guarantee ring 36 or with the cap wall 31, the cross section is small and particularly weak.
According to a preferred embodiment, the first separation line 62 and the second separation line 64 have at least in part a wavy circumferential development, so that also the cap wall 31, the guarantee band 38 and the guarantee ring 36 have at least partially a wavy circumferential development, axially interpenetrating each other and forming ridges and respective hollows, i.e. protrusions and respective recesses.
According to a preferred embodiment, the guarantee ring 36 comprises a ring wall 360 comprising a ring upper face 36 a, which delimits the ring wall 360 at the top.
According to an embodiment, the ring wall 360 also comprises a lower face 36 b, for example in the form of a circular crown lying on an imaginary plane orthogonal to the cap axis Y-Y, a cylindrical outer side surface 36 c and an inner side surface 36 d.
According to a preferred embodiment, the ring upper face 36 a consists of a corrugated surface, preferably sinusoidal, comprising at least one ring ridge 96 and/or one ring hollow 86, preferably which follow each other circumferentially.
According to a preferred embodiment, each ring hollow 86 has a bottom ring surface 86′, while each ring ridge 96 has a ring ridge surface 96′. Preferably, the bottom ring surface 86′ and the ring ridge surface 96′ are curved surfaces.
According to a preferred embodiment, the cap wall 31, at the lower edge 33, comprises an annular cap lower face 31 b which delimits it at the bottom.
According to a preferred embodiment, the cap lower face 31 b consists of a corrugated surface, preferably sinusoidal, comprising at least one cap ridge 80 and/or at least one cap hollow 90, preferably which follow each other circumferentially.
According to a preferred embodiment, each ring cap hollow 90 has a bottom cap surface 90′, while each cap ridge 80 has a cap ridge surface 80′. Preferably, the bottom cap surface 90′ and the cap ridge surface 80′ are curved surfaces.
According to a preferred embodiment, the guarantee band 38 comprises an upper band face 38 a and a lower band face 38 b.
Preferably, the upper band face 38 a and the lower band face 38 b consist of a corrugated surface, preferably sinusoidal. The upper band face 38 a comprises at least one band ridge 92 and/or at least one band hollow 82, preferably following one another circumferentially. The lower band face 38 b comprises at least one band ridge 84 and at least one band hollow 94, preferably following one another circumferentially.
Preferably, a band hollow 82 is located at a band ridge 84 and a band ridge 92 is located at a band hollow 94. In other words, the band depression 82 overlies the band ridge 84 and is aligned axially therewith; the band ridge 92 overlies the band depression 94 and is axially aligned therewith. Each band hollow 82, 94 has a cap bottom surface 82′, 94′, while each band ridge 84, 92 has a band ridge surface 84′, 92′; preferably, they are curved surfaces.
When the guarantee seal 34 is intact, a cap ridge 80 is contained within a relevant band hollow 82 and a band ridge 84 is contained within a relevant ring hollow 86. Furthermore, a ring ridge 96 is contained within a relevant band hollow 94, and a band ridge 92 is contained within a relevant cap hollow 90.
In other words, the cap wall 31 has at least one axial projection 80, which corresponds to the relevant axial indent 82 of the guarantee band 38. In axial correspondence with the axial indent 82, the guarantee band 38 has an axial projection 84, which corresponds to the relevant axial indent 86 of the guarantee ring 36. According to a further example, the cap wall 31 has at least one axial indent 90 which corresponds to the relevant axial projection 92 of the guarantee band 38. In axial correspondence with the axial projection 92, the guarantee band 38 has an axial indent 94, which corresponds to the relevant axial projection 96 of the guarantee ring 36.
According to a preferred embodiment, in a closure configuration in which the closure 3 is mounted on the spout unit 2, the first attachment portion 66 and the second attachment portion 68 are positioned in axial correspondence with a leading edge 27′, 27″.
According to a preferred embodiment, the over-cap 5, preferably made of plastics material in a single piece, for example by injection molding, comprises an annular grip 50. The grip 50 is spaced radially outward from the cap 30, preferably from the cap wall 31.
According to a preferred embodiment, the over-cap 5 further comprises flaps 52 which make the grip 50 integral with the cap 30.
According to a preferred embodiment, the grip 50 has a grip opening 55 at the top, i.e., on the side of the cap base 32, which grip opening is delimited by an opening edge 550 that overlaps the cap base 32 and is arranged axially spaced therefrom.
According to a preferred embodiment, the handle 40 comprises two wing portions 41 extending, from the cap wall 31, substantially on an imaginary plane containing the cap axis Y-Y, in two opposite directions.
Preferably, said wing portions 41 comprise panel portions 42 and reinforcing ribs 43 integral with said panel portions 42.
According to a second embodiment, the handle 40 comprises a gripping blade 45, for example protruding axially from the cap base 32 and/or protruding radially from the cap wall 31, and is also provided with a peripheral edge 46 which is enlarged with respect to the gripping blade 45.
Preferably, the gripping blade 45 has a flat shape, lying substantially on the imaginary plane which contains the cap axis Y-Y.
According to a preferred embodiment, the gripping blade 45 extends mainly along an axis substantially orthogonal to the cap axis Y-Y; preferably, the peripheral edge 46 is positioned above the gripping blade 45.
According to a preferred embodiment, the cap unit 4 comprises a clearance element 48, preferably positioned on the cap base 32.
According to a variant embodiment, the closure 3 is made of plastics material in a single piece, for example by injection molding.
According to a preferred embodiment, once the closure 3 has been applied to the spout unit 2, the guarantee ring 36 is at least partially housed in the ring seat 100, unable to be withdrawn axially, except by damage. The guarantee band 38, however, is located outside of the ring seat 100, above the engagement plate 26.
In an embodiment, the guarantee ring 36 is freely rotatable in the ring seat 100.
According to a further embodiment, locking means are provided which prevent or limit the free rotation of the guarantee ring 36 in the ring seat 100.
According to a preferred embodiment, on the inner side surface 36 d of the guarantee ring 36 there is a continuous or discontinuous lower annular protrusion 361 which, when the guarantee ring 36 is applied to the spout unit 2, creates an axial constraint, by snap engaging the ring seat 100.
According to a preferred embodiment, a continuous or discontinuous upper protrusion 362 is also present on the inner side surface 36 d, so that a continuous or discontinuous plate housing 365 is formed between the lower protrusion 361 and the upper protrusion 362, for housing the engagement plate 26.
According to a preferred embodiment, a plurality of openings 37 are formed in the guarantee ring 36 so that the guarantee ring 36 is more flexible.
According to a preferred embodiment, the cap unit 4 comprises a drip-catching device 15 suitable for sealingly engaging the spout 10, so that the product contained in the packaging does not escape, in particular when the package is turned upside down.
Preferably, the drip-catching device 15 comprises a drip-catching ring 18 internally integrated with the cap base 32, i.e. inside the cap 30. Furthermore, the cap unit 4 comprises an annular housing 17 between the cap wall 31 and the drip-catching ring 18, suitable for housing the spout 10, preferably the spout lip 28 in a closed configuration, for example by means of interlocking engagement. Preferably, said engagement is with interference.
According to a preferred embodiment, the drip-catching ring 18 comprises a reinforcing ring 180, positioned at the base of the drip-catching ring 18 in proximity to the cap base 32. This reinforcing ring 180 allows an engagement with interference to be obtained preferably between the inner surface 13 of the spout 10 and the drip-catching ring 18.
According to a preferred embodiment, a radially protruding engagement element 310, either continuous or discontinuous, is formed internally in the cap wall 31. Preferably, said engagement element 310 is positioned below the annular housing 17.
Preferably, said engagement element 310, in a closed configuration in which the cap 3 is engaged with the spout 10, is suitable for engaging the spout backing 29 so as to cause an audible signal upon correct engagement.
According to the invention, the cap unit 4 comprises at least one cap cam portion 35. This cap cam portion 35 extends internally starting from the cap base 32. Preferably, the cap cam portion 35 has an extension equal to a quarter of the circumference.
This cap cam portion 35 is at least partially complementary to the spout cam portion 25.
It is noted that the definition of “cap cam portion” does not include the profile of a thread. Indeed, the present invention intends to avoid the use of a thread on the cap, in order to lighten it.
Preferably, the cap cam portion 35 defines a lower cam surface 350, inclined with respect to the cap axis Y-Y and having an extension equal to at least a quarter of the circumference.
According to a first embodiment, the lower cam surface 350 has an arcuate shape with a lowered center so as to define two opposite slopes. Preferably, the center is lowered with respect to the cap base 32 and a first and second end are close to this cap base 32. Preferably, the cap cam portion 35 has an extension equal to half of the circumference.
In a preferred embodiment, the lower cam surface 350 has a flattened center and/or the arc does not necessarily have a constant radius.
According to a second embodiment (not shown), the lower cam surface 350 has a single inclined surface, i.e. one end is proximal with respect to the cap base 32 and one end is lowered with respect to the cap base 32.
According to a preferred embodiment, the closure 3 comprises a plurality of cap cam portions 35, preferably comprises two cap cam portions 35, diametrically opposite and arranged symmetrically with respect to the cap axis Y-Y.
According to a preferred embodiment, the cap cam portions 35 have an extension equal to half of the circumference and, in this way, the ends of one are close to the ends of the other, preferably in contact so as to form a single cap cam portion 25 in which high sections 322, proximal to the cap base 32, and low sections 324, distal to the cap base 32, alternate.
In the closed configuration (FIG. 1 ), the cap 30 is positioned on the spout 10, the at least one cap cam portion 35 engages the at least one spout cam portion 25, and preferably the upper cam surface 250 is at least partially in contact with the lower cam surface 350. Preferably, the spout lip 28 is housed in the housing 17. In a disengagement configuration, by rotating the cap 3 with respect to the spout 10 around the cap axis Y-Y, preferably by at least a quarter turn, the interaction between the at least one cap cam portion 35 and the at least one spout cam portion 25, preferably the contact engagement between the upper cam surface 250 and the lower cam surface 350, causes an axial lifting of the cap 3 with respect to the spout 10.
By disengaging the closure 3 from the spout 10, by virtue of the rotation of the cap 30 around the cap axis Y-Y with respect to the spout 10 and to the axial lifting of the cap 30 with respect to the spout 10 due, as described above, to the interaction between the at least one spout cam portion 25 and a cap cam portion 35, the bridges 60 break, so at the end of the disengagement, the guarantee band 38 takes the form of a string 38′, connected to the guarantee ring 36 by the first attachment portion 66 and to the cap wall 31, preferably at the lower edge 33, by the second attachment portion 38 (FIGS. 1 a to 1 d and 2 a to 2 d ). The closure 3, although disengaged from the spout 10, thus remains connected to the spout unit 2 (open configuration).
In other words, the axial lifting of the cap 30 with respect to the spout 10, dictated by the interaction between the cam portions 25, 35, causes the breaking of the breakable bridges 60.
In particular, by virtue of the axial lifting of the cap 30 due to the interaction between the at least one spout cam portion 25 and the cap cam portion 35, there is no interaction between the guarantee ring 36, the guarantee band 38 and the cap wall 31 during the disengagement between the cap 30 and the spout 10.
According to a preferred embodiment, the cam portions 25, 35 are such as to allow rotation of the cap 3 both in a clockwise and counter-clockwise direction. This embodiment is characterized by the presence of cam portions 25, 35, the cam surfaces 250, 350 of which have an arcuate shape comprising two opposite slopes, as described above.
Innovatively, the closure assembly forming the subject of the present fully achieves the proposed object whilst overcoming the drawbacks discussed above in reference to the prior art.
In particular, the closure assembly is lighter due to a smaller quantity of plastics material used with respect to the known closure assembly solutions.
It is clear that those skilled in the art may, in order to meet specific needs, make several changes or substitutions of elements with other functionally equivalent ones. These variants are also contained within the scope of protection as defined by the following claims. Moreover, each variant described as belonging to a possible embodiment may be implemented independently of the other variants described.

Claims

What is claimed is:

1-17. (canceled)

18. A closure assembly for a package with a flexible thin-walled bag for containing fruit juices and puree, yoghurt, and energy drinks, comprising:

a spout unit extending along a spout axis, comprising a connection portion suitable for being hermetically applied to the flexible thin-walled bag, and a spout comprising an inner surface, wherein the spout unit further comprises at least one spout cam portion made on said inner surface;

a closure applicable to the spout unit and comprising a cap unit comprising a cap engageable with the spout and extending along a cap axis, wherein the cap comprises a cap wall and a cap base that closes the cap wall at one end, wherein the cap unit further comprises at least one cap cam portion extending inwards from the cap base;

wherein the at least one cap cam portion is at least partially complementary to the at least one spout cam portion;

wherein, in a disengagement configuration, by rotating the cap about the cap axis with respect to the spout, an interaction between the at least one cap cam portion and the at least one spout cam portion causes an axial lifting of the cap with respect to the spout;

wherein the at least one spout cam portion defines an upper cam surface inclined with respect to the spout axis and having at least one extension equal to at least one fourth of the circumference; and

wherein the upper cam surface is arch shaped with a lowered center so as to define two opposite slopes and has an extension equal to half the circumference.

19. The closure assembly of claim 18, wherein the at least one spout cam portion is made protruding radially from said inner surface, wherein the spout comprises a mouth for a product to come out, and wherein the at least one spout cam portion is made close to said mouth.

20. The closure assembly of claim 18, wherein the spout unit comprises two spout cam portions that are diametrically opposite and arranged symmetrically to the spout axis.

21. The closure assembly of claim 18, wherein the spout comprises an enlarged spout lip, and beneath said spout lip, comprises a spout backing so that the spout is thinned at said spout backing.

22. The closure assembly of claim 18, wherein the at least one cap cam portion defines a lower cam surface inclined with respect to the cap axis and having an extension equal to at least one fourth of the circumference.

23. The closure assembly of claim 22, wherein the lower cam surface is arch shaped with a lowered center so as to define two opposite slopes and has an extension equal to half the circumference.

24. The closure assembly of claim 18, wherein the closure comprises two cap cam portions that are diametrically opposite and arranged symmetrically to the cap axis.

25. The closure assembly of claim 18, wherein the cap unit comprises a drip-catching device suitable for engaging the spout, so that a product contained in the package cannot escape.

26. The closure assembly of claim 25, wherein the spout comprises an enlarged spout lip, and beneath said spout lip, comprises a spout backing so that the spout is thinned at said spout backing, wherein the drip-catching device comprises a drip-catching ring internally integrated with the cap base, and wherein the cap unit comprises an annular housing between the cap wall and the drip-catching ring, suitable for housing the spout lip in a closing configuration with an interference engagement.

27. The closure assembly of claim 21, wherein a radially protruding engagement element is internally made in the cap wall, the radially protruding engagement element being either continuous or discontinuous and suitable for engaging the spout backing so as to cause an audible signal upon correct engagement.

28. The closure assembly of claim 18, wherein the closure further comprises a guarantee seal for highlighting a first opening of the closure, comprising:

a guarantee ring at least partially accommodated in a ring seat of the spout;

a guarantee band which, in an unbroken seal configuration, axially overlaps the guarantee ring, the guarantee band being separated from the guarantee ring by a first separation line and from the cap by a second separation line; and

a plurality of breakable bridges which, in the unbroken seal configuration, join the guarantee ring to the guarantee band and the guarantee band to the cap wall;

wherein the first separation line and the second separation line have at least partially a wavy circumferential development, so that the cap wall, the guarantee band and the guarantee ring also have at least partially a wavy circumferential development by axially interpenetrating each other.

29. The closure assembly of claim 18, wherein the closure further comprises a handle comprising two wing portions extending, from the cap wall, substantially on an imaginary plane containing the cap axis, in two opposite directions.

30. The closure assembly of claim 18, wherein the closure further comprises a handle comprising a gripping blade and a peripheral edge that is enlarged with respect to said gripping blade.

31. The closure assembly of claim 18, wherein the closure further comprises an over-cap comprising an annular grip radially spaced apart outside the cap wall.

32. A package comprising:

a flexible thin-walled bag, and

the closure assembly of claim 18,

wherein the spout unit of the closure assembly is hermetically applied to the flexible thin-walled bag.