Patent Grant
7014055
The present invention relates to a synthetic resin container closure formed from a synthetic resin material as a single unit and, more specifically, to a synthetic resin container closure which has a circular top panel wall and a cylindrical skirt wall extending downwardly from the peripheral edge of this top panel wall, one or two cylindrical sealing protrusions that extend downwardly being formed on the inner surface of the top panel wall.
A synthetic resin container closure which is wholly formed from an appropriate synthetic resin such as polypropylene or polyethylene as a single unit has been proposed as a container closure for drink or beverage containers and has been put to practical use. The container closure has a circular top panel wall and a cylindrical skirt wall extending downwardly from the peripheral edge of this top panel wall, and one or two cylindrical sealing protrusions extending downwardly are formed on the inner surface of the top panel wall. In a container closure disclosed in FIG. 3 of Japanese Unexamined Laid-Open Patent Publication 10-35699, two cylindrical protrusions, that is, an outer cylindrical protrusion and an inner cylindrical sealing protrusion both extending downwardly, are formed on the inner surface of the top panel wall. On the inner surface of the top panel wall is further formed an annular sealing ridge adjacent to the base portion of the outer cylindrical protrusion. The trade name of a product, the name of a manufacturer or distributor and the like are printed on the outer surface of the top panel wall by offset printing, for example. A female thread is formed on the inner peripheral surface of the skirt wall. This container closure is mounted on a container having a male thread formed on the outer peripheral surface of a mouth-neck portion. When the female thread of the container closure is screwed onto the male thread of the mouth-neck portion to mount the container closure on the mouth-neck portion, the inner cylindrical sealing protrusion is brought into close contact with the inner peripheral surface of the mouth-neck portion, and the annular sealing ridge is also brought into close contact with the boundary region between the outer peripheral surface and the top surface of the mouth-neck portion. The outer cylindrical protrusion is brought into not close contact, but relatively loose contact with the outer peripheral surface of the mouth-neck portion to assist close contact of the annular sealing ridge with the boundary region between the outer peripheral surface and the top surface of the mouth-neck portion.
However, the above container closure of the prior art involves the following problems to be solved. Firstly, in the above container closure of the prior art, it is necessary to fully and surely satisfy the basic requirement that when the container closure is mounted on the mouth-neck portion of the container, the mouth-neck portion is sealed hermetically without fail and when the mouth-neck portion is to be opened, appropriate torque is applied to the container closure to turn the container closure, without requiring excessive torque, so that the container closure can be removed from the mouth-neck portion. In addition, it is important that when the mouth-neck portion is to be opened, the sealing of the mouth-neck portion should be released after the container closure is turned at an angle larger than the required rotation angle. Describing this point in more detail, a weakening line is generally formed in the skirt wall of the container closure such that it extends in a circumferential direction, the skirt wall is divided into a main portion above the weakening line and a tamper-evident skirt portion below the weakening line, the above female thread is formed on the inner peripheral surface of the main portion, and an engaging means having an appropriate shape is formed on the inner peripheral surface of the tamper-evident skirt portion. When the container closure is mounted on the mouth-neck portion of the container, the engaging means is engaged with an engaging jaw portion formed on the outer peripheral surface of the mouth-neck portion. When the container closure is turned in an opening direction to open the mouth-neck portion of the container, the weakening line is at least partially broken, whereby the engagement of the engaging means with the engaging jaw portion is released, and the container closure is allowed to be removed from the mouth-neck portion. It is important that when the container closure is turned in the opening direction, the sealing of the mouth-neck portion should be released after the weakening line is at least partially broken. If the sealing of the mouth-neck portion is released before the weakening line is at least partially broken, there occurs such a situation that though the container closure has been tampered to be turned in the opening direction and the sealing of the mouth-neck portion has been released, the weakening line is not broken, and accordingly an indication that the container closure has been tampered and the sealing of the mouth-neck portion has been released does not remain. Therefore, in the above container closure of the prior art, there is a tendency that the sealing of the mouth-neck portion is released before the container closure is turned at a predetermined rotation angle owing to the production tolerance of the container closure and/or the mouth-neck portion or owing to the thermal deformation of the container closure and/or the mouth-neck portion, and there may occur a case where the above basic requirement can not be satisfied.
Secondly, the above container closure is formed from an appropriate synthetic resin by compression molding or injection molding. The molding efficiency of the molding step greatly depends on the required cooling time in the mold, as is well known to people having ordinary skill in the art. When the molded container closure is removed from the mold before the passage of the required cooling time, deformation greater than the permissible range may occur in the circular top panel wall. More specifically, there is a tendency for the center of the top panel wall to be indented, and consequently the top panel wall has a depressed shape more than the permissible range. To shorten the required cooling time without causing deformation greater than the permissible range in the top panel wall, it is known for the thickness of the top panel wall, particularly the center portion positioned on the inner side of the inner cylindrical sealing protrusion, to be reduced to promote the cooling of the top panel wall, particularly the center portion thereof. However, when the thickness of the top panel wall, particularly the center portion thereof, is reduced, another problem arises as follows. When the outer surface of the top panel wall is to be printed, the container closure is mounted on a mandrel to contact the top surface of the mandrel to the inner surface of the center portion of the top panel wall, and then an offset printing roller made from a material having elasticity, such as synthetic rubber, is applied to the outer surface of the top panel wall of the container closure in a printing area. Even when the outer surface of the top panel wall has some distortion of ordinary permissible degree, it is important for carrying out fully satisfactory printing that the printing roller should be compressed by approximately 1 mm when the printing roller is applied to the outer surface of the top panel wall of the container closure. In this case, when the thickness of the top panel wall is reduced to 1 mm for example, the space between the peripheral surface of the printing roller and the top surface of the mandrel to which the container closure is not mounted must be set to substantially zero. In a case of the setting being made like this, if the mandrel is moved through the printing area without the container closure mounted thereon for some accidental reason, printing ink will be adhered to the top surface of the mandrel, and the inner surface of the center portion of the top panel wall of the container closure will be stained by the printing ink when the container closure is then mounted on this mandrel. When the space between the top surface of the mandrel and the peripheral surface of the printing roller is made large to prevent this situation, the amount of compression of the printing roller at the time when the printing roller is applied to the outer surface of the top panel wall of the container closure mounted on the mandrel becomes too small, thereby making it impossible to carry out satisfactory printing in a case where the outer surface of the top panel wall has some general permissible distortion. Further, if the thickness of the top panel wall, particularly the center portion, is reduced, the rigidity of the top panel wall is inevitably reduced, whereby the so-called flexibility of the inner cylindrical sealing protrusion becomes too large, contact pressure between the inner cylindrical sealing protrusion and the inner peripheral surface of the mouth-neck portion of the container becomes too small, and hence the hermetical sealing of the mouth-neck portion is liable to be insufficient.
It is therefore the first object of the present invention to provide a novel and improved synthetic resin container closure which can seal hermetically the mouth-neck portion of a container fully reliably when it is mounted on the mouth-neck portion of the container, can be removed from the mouth-neck portion by applying appropriate torque to turn it without requiring excessive torque, so as to open the mouth-neck portion, and simultaneously can release the hermetical sealing of the mouth-neck portion after turning it at an angle larger than the required rotation angle to open the mouth-neck portion.
It is the second object of the present invention to provide a novel and improved synthetic resin container closure which does not cause any inconvenience in the printing step and does not cause unsatisfactory sealing of the mouth-neck portion of a container even though the cooling time required for compression molding or injection molding can be considerably reduced.
According to the first aspect of the present invention, there is provided a container closure which has a circular top panel wall and a cylindrical skirt wall extending downwardly from the peripheral edge of the top panel wall and which is formed from a synthetic resin as a single unit, wherein
The container closure provided according to the first aspect of the present invention can be advantageously used when a container formed from an appropriate synthetic resin such as polyethylene terephthalate (the present invention is not limited to this) is filled with contents heated at approximately 80 to 95° C. (so-called hot packing). As is well known to people having ordinary skill in the art, after the synthetic resin container to be filled with contents heated at approximately 80 to 95° C. is molded into a predetermined shape, the mouth-neck portion thereof is crystallized by heating, thereby slightly reducing the dimensional accuracy of the mouth-neck portion.
Preferably, the outer peripheral surface of the inner cylindrical sealing protrusion extends downwardly in such a manner that it is inclined outward in a radial direction at an inclination angle θ1 with respect to the center axis of the container closure and then, extends downwardly in such a manner that it is inclined inward in a radial direction at an inclination angle θ2 with respect to the center axis. The inclination angle θ1 may be 5 to 25° and the inclination angle θ2 may be 5 to 30°. The inner peripheral surface of the inner cylindrical sealing protrusion extends downwardly in such a manner that it is inclined outward in a radial direction at an inclination angle θ3 with respect to the center axis, and then, extends substantially parallel with the center axis. Preferably, the outer peripheral surface of the inner cylindrical sealing protrusion has the maximum external diametetr D3 at a position below, and away from, the inner surface of the top panel wall by a length L1 of 2.50 to 3.50 mm. In a preferred embodiment, the inclination angle θ3 of the inner peripheral surface of the inner cylindrical sealing protrusion is larger than the inclination angle θ1 of the outer peripheral surface of the inner cylindrical sealing protrusion at a position above the portion having the maximum external diameter D3. The inner peripheral surface of the outer cylindrical sealing protrusion extends downwardly in such a manner that it is inclined inward in a radial direction at an inclination angle θ4 with respect to the center axis, and then, extends downward in such a manner that it is inclined outward in a radial direction. The inclination angle θ4 may be 13 to 23°. The outer peripheral surface of the outer cylindrical sealing protrusion extends downwardly in such a manner that it is inclined inward in a radial direction at an inclination angle θ5 with respect to the center axis. The inclination angle θ5 is larger than the inclination angle θ4 and may be 15 to 25°. Preferably, the inner peripheral surface of the outer cylindrical sealing protrusion has the minimum internal diameter D1 at a position below, and away from, the inner surface of the top panel wall by a length L2 of 0.60 to 1.50 mm.
If (D2−D1) and (D3−D4) are too small, a tendency occurs that the hermetical sealing of the mouth-neck portion may become unsatisfactory, and at the same time the sealing of the mouth-neck portion may be released before the container closure is turned at a required rotation angle to open the mouth-neck portion. On the other hand, if (D2−D1) and (D3−D4) are too large, there is a tendency that torque to be applied to the container closure to open the mouth-neck portion may become excessive.
According to a second aspect of the present invention, to attain the second object of the present invention, there is provided a container closure which has a circular top panel wall and a cylindrical skirt wall extending downwardly from the peripheral edge of the top panel wall, a cylindrical sealing protrusion extending downwardly to be brought into close contact with the inner peripheral surface of the mouth-neck portion of a container being formed on the inner surface of the top panel wall, and which is formed from a synthetic resin as a single unit, wherein
Preferably, the thickness T1 is 0.90 to 1.10 mm, the thickness T2 is 0.30 to 0.50, and the total (T1+T2) of the thickness T1 and the thickness T2 is 1.30 to 1.50 mm. In a preferred embodiment, the ribs extend radially. The ribs are arranged at equiangular intervals and extend continuously from the center of the center portion to the peripheral edge of the top panel wall. The ribs have a rectangular cross sectional form, and when in a bottom view the area of the center portion of the top panel wall is represented by S1 and the total area of the ribs is represented by S2, S1 and S2 satisfy 0.10S1<S2<0.40S1, preferably 0.15S1<S2<0.35S1.
If the thickness T1 of the center portion of the top panel wall is too large, the thickness T2 of each of the ribs is too large, or the total of the thickness T1 of the center portion of the top panel wall and the thickness T2 of each of the ribs is too large, the cooling time required for preventing deformation larger than the permissible range in the top panel wall will become long. If the thickness T1 of the center portion of the top panel wall is too small, the rigidity of the top panel wall will become too low and the hermetical sealing of the mouth-neck portion of the container will become insufficient. If the thickness T2 of each of the ribs is too small or the total of the thickness T1 of the center portion of the top panel wall and the thickness T2 of each of the ribs is too small, the rigidity of the top panel wall will become too low and at the same time, it becomes necessary to set the space between the top surface of a mandrel and the peripheral surface of a printing roller to an extremely small value in the printing step, and there is a possibility that the inner surface of the center portion of the top panel wall is stained by a printing ink as described above.
Further, according to a third aspect of the present invention, to attain the first object of the present invention, there is provided a container closure which has a circular top panel wall and a cylindrical skirt wall extending downwardly from the peripheral edge of the top panel wall and which is formed from a synthetic resin as a single unit, wherein
The container closure provided according to the third aspect of the present invention can be advantageously used when a container formed from an appropriate synthetic resin such as polyethylene terephthalate is filled with contents having a normal temperature in a germ-free or germ reduced state (so-called aseptic filling). As is well known to people having ordinary skill in the art, the synthetic resin container filled with contents having a normal temperature has a mouth-neck portion with fairly high dimensional accuracy because the mouth-neck portion is not crystallized by heating.
Preferably, the outer peripheral surface of the outer cylindrical sealing protrusion extends substantially parallel with the center axis. Preferably, the outer peripheral surface of the inner cylindrical sealing protrusion extends downwardly in such a manner that it is inclined outward in a radial direction at an inclination angle θ1 with respect to the center axis of the container closure and then, extends downwardly in such a manner that it is inclined inward in a radial direction at an inclination angle θ2 with respect to the center axis. The inclination angle θ1 may be 5 to 25°. Preferably, the inner peripheral surface of the inner cylindrical sealing protrusion extends downwardly in such a manner that it is inclined outward in a radial direction at an inclination angle θ3 with respect to the center axis and then, extends substantially parallel with the center axis. Preferably, the outer peripheral surface of the inner cylindrical sealing protrusion has the maximum external diameter D3 at a position below, and away from, the inner surface of the top panel wall by a length L1 of 2.50 to 3.50 mm. In a preferred embodiment, the inclination angle θ3 of the inner peripheral surface of the inner cylindrical sealing protrusion is larger than the inclination angle θ1 of the outer peripheral surface of the inner cylindrical sealing protrusion at a position above the portion having the maximum external diameter D3.
If (D3−D4) is too small, a tendency occurs that the hermetical sealing of the mouth-neck portion may become unsatisfactory and at the same time, the hermetical sealing of the mouth-neck portion may be released before the container closure is turned at a required rotation angle to open the mouth-neck portion. On the other hand, if (D3−D4) is too large, there is a tendency that torque to be applied to the container closure to open the mouth-neck portion may become excessive. The inner peripheral surface of the outer cylindrical sealing protrusion extends downwardly in such a manner that it is inclined outward in a radial direction at an inclination angle θ6 with respect to the center axis and then, extends downwardly and radially outwardly in an arc form, whereby the container closure can be mounted on the mouth-neck portion sufficiently and easily and there is virtually no possibility that the container closure is mounted improperly.
A synthetic resin container closure constituted according to preferred embodiments of the present invention will be described in further detail with reference to the accompanying drawings hereinafter.
Describing with reference to
A truncated conical portion 20 which has an external diameter gradually increasing downward is formed near the lower end of the outer peripheral surface of the main portion 10 of the skirt wall 6. The outer peripheral surface of the tamper-evident skirt portion 12 is also formed in a truncated conical shape whose external diameter gradually increases downward. On a portion above the truncated conical portion 20 of the outer peripheral surface of the main portion 14 are formed knurls 22 for preventing the slippage of the fingers placed thereon. A female thread 24 is formed on the inner peripheral surface of the main portion 10 of the skirt wall 6. In the female thread 24 are formed axially extending notches 26 at appropriate intervals in the circumferential direction. The above notches 26 constitute a so-call air passage when the mouth-neck portion of the container is opened.
On the inner peripheral surface of the tamper-evident skirt portion 12 is formed an engaging means 28. The engaging means 28 in the illustrated embodiment is composed of a plurality of, for example, 8 flap pieces 30 arranged at appropriate spaces in a circumferential direction. Each of the flap pieces 30 is projected inward in a radial direction from the base edge connected to the inner peripheral surface of the tamper-evident skirt portion 12 in such a manner that it is inclined upward. If desired, the engaging means may be composed of flap pieces having another appropriate shape, ribs, protrusions or the like.
With reference to
For the convenience of explanation, the inner cylindrical sealing protrusion 34 will be first described in detail before explanation of the outer cylindrical sealing protrusion 32. The inner cylindrical sealing protrusion 34 in the illustrated embodiment extends downwardly from the inner surface of the top panel wall 4 and its outer peripheral surface extends downwardly in a such a manner that it is inclined outward (left direction in
The inner peripheral surface of the inner cylindrical sealing protrusion 34 extends downwardly in a such a manner that it is inclined outward in a radial direction at an inclination angle θ3 with respect to the above center axis 38 and then extends substantially parallel with the above center axis 38. From the viewpoint of the ease of taking out of a mold after molding, the above inclination angle θ3 of a portion above the bent portion 40 is advantageously larger than the above inclination angle θ1 and may be approximately 7 to 30°. Since the outer peripheral surface and inner peripheral surface of the inner cylindrical sealing protrusion 34 are formed as described above, as will be clearly understood with reference to
The outer cylindrical sealing protrusion 32 in the illustrated embodiment extends also downwardly from the inner surface of the top panel wall 4. The length of extension of the outer cylindrical sealing protrusion 32 is smaller than the length of extension of the inner cylindrical sealing protrusion 34 and nearly ⅓ the length of extension of the inner cylindrical sealing protrusion 34. The inner peripheral surface of the outer cylindrical sealing protrusion 32 extends downwardly in such a manner that it is inclined inward in a radial direction at an inclination angle θ4 with respect to the above center axis 38 and then, extends downwardly in such a manner that it is inclined outward in a radial direction. The above inclination angle θ4 may be approximately 13 to 23°. A portion extending downwardly in such a manner that it is inclined inward in a radial direction of the inner peripheral surface of the outer cylindrical sealing protrusion 32 is linear, and a portion extending downwardly in such a manner that it is inclined outward in a radial direction is nearly arc-shaped. The inner peripheral surface of the outer cylindrical sealing protrusion 32 has the minimum internal diameter D1 at a portion where its inclination direction is changed, that is, at the boundary between the linear portion and the nearly arc-shaped portion. As will become clear from a description to be given later, the portion where the inclination direction is changed of the inner peripheral surface of the outer cylindrical sealing protrusion 32 is brought into close contact with the outer peripheral surface of the mouth-neck portion of the container, and the minimum internal diameter D1 is therefore the minimum internal diameter of the portion to be brought into close contact with the mouth-neck portion of the container, of the outer cylindrical sealing protrusion 32. The portion having the minimum internal diameter D1 is suitably located below, and away from, the inner surface of the top panel wall 4 by a length L2 of 0.60 to 1.50 mm.
The outer peripheral surface of the outer cylindrical sealing protrusion 32 extends downwardly linearly in such a manner that it is inclined inward in a radial direction at an inclination angle θ5 with respect to the above center axis 38. The inclination angle θ5 is slightly larger than the above inclination angle θ4 and is 15 to 25°. The thickness of the outer cylindrical sealing protrusion 32 is, therefore, gradually decreased downward favorably.
The annular sealing ridge 36 arranged adjacent to the base portion of the outer cylindrical sealing protrusion 32 has a nearly semicircular cross section. The amount of projection of the annular sealing ridge 36 is much smaller than the length of extension of the inner cylindrical sealing protrusion 34 and the length of extension of the outer cylindrical sealing protrusion 32, and the inner cylindrical sealing protrusion 34 and the outer cylindrical sealing protrusion 32 have relatively high flexibility to allow them to be bent inward and outward in a radial direction while the annular sealing ridge 36 has substantially no flexibility.
According to another aspect of the present invention, it is important that the thickness of the top panel wall 4, particularly the thickness of the center portion 42 located on the inner side of the inner cylindrical sealing protrusion 34, should be made fully small in order to shorten the required cooling time in the mold at the time of forming the container closure by compression molding or injection molding, that is, the duration from the time when a fluidized synthetic resin is poured into a desired shape in the mold to the time when the mold is opened and removal of the molded container closure is started. In the illustrated embodiment, the center portion 42 of the top panel wall 4 has a thickness T1, an intermediate portion 44 between the inner cylindrical sealing protrusion 34 and the annular sealing ridge 36 of the top panel wall 4 has a thickness T1-A, a peripheral portion 46 located on the outer side of the annular sealing ridge 36 has a thickness T1-B, and the thickness must satisfy T1<T1-A<T1-B. It is important that the thickness T1 of the center portion 42 should be 0.80 to 1.20 mm, preferably 0.90 to 1.10 mm. If the thickness T1 of the center portion 42 is too large, the required cooling time in the mold will become long and the molding efficiency will lower. If the thickness T1 of the center portion 42 is too small, the rigidity of the top panel wall 44 may become too low and the hermetical sealing of the mouth-neck portion of the container may become insufficient. The thickness T1-A of the intermediate portion 44 may be approximately 1.10 to 1.50 mm and the thickness T1-B of the peripheral portion 46 may be approximately 1.40 to 1.80 mm.
With reference to
To open the mouth-neck portion 50 of the container, the container closure 2 is turned in an opening direction, that is, in a counterclockwise direction when viewed from above in
In the container closure 102 shown in
With further reference to
The inner peripheral surface of the inner cylindrical sealing protrusion 134 extends downwardly in such a manner that it is inclined outward in a radial direction at an inclination angle θ3 with respect to the above center axis 138, and then, extends substantially parallel with the above center axis 138. The inclination angle θ3 may be approximately 7 to 30°. Since the outer peripheral surface and inner peripheral surface of the inner cylindrical sealing protrusion 134 are formed as described above, as is clearly understood with reference to
The outer cylindrical sealing protrusion 132 of the container closure 102 also extends downwardly from the inner surface of the top panel wall 104. The length of extension of the outer cylindrical sealing protrusion 132 is smaller than the length of extension of the inner cylindrical sealing protrusion 134 and is approximately ⅓ the length of extension of the inner cylindrical sealing protrusion 134. In the case of an aseptic filling-applicable container, the dimensional accuracy of the mouth-neck portion is relatively high because it is not necessary to crystallize the mouth-neck portion by heating after the container is molded to a desired shape. Therefore, according to the experience of the inventors of the present invention, hermetical sealing by the inner cylindrical sealing protrusion 134 fully satisfies requirements for the hermetical sealing of the mouth-neck portion basically. The outer cylindrical sealing protrusion 132 contributes to the positioning of the container closure 102 when the container closure 102 is mounted on the mouth-neck portion or the prevention of entry of germs from the outside. From this point of view, the inner peripheral surface of the outer cylindrical sealing protrusion 132 extends linearly in such a manner that it is inclined outward in a radial direction at an inclination angle θ6 with respect to the above center axis 138 and then, extends downwardly and radially outwardly in an arc form. The above inclination angle θ6 may be approximately 10 to 25°. As is understood with reference to
Also in the container closure 102 shown in
The annular sealing ridge 136 is formed adjacently to the base portion of the outer peripheral surface of the inner cylindrical sealing protrusion 134 and nearly rectangular as a whole, and the lower end portion of the inner peripheral surface thereof has a circular arc cross sectional form with a small curvature radius. The amount of projection of the annular sealing ridge 136 is much smaller than the length of extension of the inner cylindrical sealing protrusion 134 and the length of extension of the outer cylindrical sealing protrusion 132, and the inner cylindrical sealing protrusion 134 and the outer cylindrical sealing protrusion 132 have relatively high flexibility such that they bend inward and outward in a radial direction, while the annular sealing ridge 136 has substantially no flexibility.
The container closure 102 shown in
In the above-described container closure 2 (102), when the mouth-neck portion 50 (150) is opened, all the bridging portions 18 on the breakable line 8 formed in the skirt wall 6 (106) of the container closure 2 (102) are broken, and the tamper-evident skirt portion 12 is completely separated from the main portion 10 of the skirt wall 6 (106) and caused to remain on the mouth-neck portion 50 (150) without being separated from the mouth-neck portion 50 (150). If desired, at least one of the bridging portions 18 on the breakable line 8 may be made a strong bridging portion which can be unbroken and kept, and a breakable line (not shown) extending in an axial direction may be formed in the tamper-evident skirt portion 12 so that when the mouth-neck portion 50 (150) is opened, the breakable line extending in an axial direction is broken to make the tamper-evident skirt portion 12 from an endless ring form into a belt form, and the tamper-evident skirt portion 12 that is kept connected to the main portion 10 of the skirt wall 6 (106) through the strong bridging portion which is unbroken and kept is also separated from the mouth-neck portion 50 (150).
A container closure having a shape shown in
A polyethylene terephthalate container having a mouth-neck portion with a nominal diameter of 28 mm and a nominal volume of 500 ml marketed under the trade name of “TSK Kuki STHE 500 Natural G” from Toyo Seikan Co., Ltd. was filled with water heated at 87° C., and the above container closure was mounted on the mouth-neck portion by applying a torque of 21 kgfcm. The container was laid horizontally for 39 seconds, returned to an upright position, and sprayed with water heated at 75° C. for 3 minutes, water heated at 50° C. for 15 minutes and water heated at 30° C. for 15 minutes. Thereafter, the container closure was left at 50° C. for 5 days.
The external diameter D2 of the mouth-neck portion of the above container was 24.94 mm and the internal diameter D4 thereof was 20.60 mm. Therefore, (D2−D1) was 0.24 mm and (D3−D4) was 0.30 mm.
Thereafter, the container closure was turned in an opening direction and removed from the mouth-neck portion of the container. The initial torque (torque that was required for starting the rotation of the container closure), the rotation angle (angle B) of the container closure before the breakable line began to be broken, and the rotation angle (angle L) of the container closure before the sealing of the mouth-neck portion was released were measured. The rotation of the container closure was carried out by placing the container inverted and the release of sealing was judged from entry of air into the container (air bubbles entered water in the container). The results of 10 container closures are shown in Table 1 below. The angle B is desired to be smaller than the angle L and hence, when the angle B is larger than the angle L, it is judged as improper BL. The initial torque is desired to be 20 kgfcm or less and hence, when the initial torque is larger than 20 kgfcm, it is judged as improper torque.
The initial torque and the angles B and L were measured in the same manner as in Example 1 except that D3 of the container closure was 21.41 mm and (D3−D4) was 0.81 mm. The results are shown in Table 2.
The initial torque and the angles B and L were measured in the same manner as in Example 1 except that D3 of the container closure was 22.00 mm and (D3−D4) was 1.40 mm. The results are shown in Table 3.
The initial torque and the angles B and L were measured in the same manner as in Example 1 except that D3 of the container closure was 20.80 mm and (D3−D4) was 0.20 mm. The results are shown in Table 4.
The initial torque and the angles B and L were measured in the same manner as in Example 1 except that D3 of the container closure was 22.15 mm and (D3−D4) was 1.55 mm. The results are shown in Table 5.
The angles B and L were measured in the same manner as in Example 1 except that D1 of the container closure was 24.84 mm and (D2−D1) was 0.10 mm. The results are shown in Table 6.
The angles B and L were measured in the same manner as in Example 1 except that D1 of the container closure was 24.70 mm and (D2−D1) was 0.24 mm. The results are shown in Table 6.
The angles B and L were measured in the same manner as in Example 1 except that D1 of the container closure was 24.92 mm and (D2−D1) was 0 mm. The results are shown in Table 6.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2000-68690 | Mar 2000 | JP | national |
| 2000-298619 | Sep 2000 | JP | national |
This application is a divisional application of Ser. No. 09/804,267 filed Mar. 13, 2001, now U.S. Pat. No. 6,779,672.
| Number | Name | Date | Kind |
|---|---|---|---|
| 3463340 | Lindstrom | Aug 1969 | A |
| 4489845 | Aichinger et al. | Dec 1984 | A |
| 4560077 | Dutt | Dec 1985 | A |
| 4566603 | Moore | Jan 1986 | A |
| 5297688 | Beck et al. | Mar 1994 | A |
| 5307945 | Hidding et al. | May 1994 | A |
| 5871111 | Pfefferkorn et al. | Feb 1999 | A |
| 6003701 | Hidding et al. | Dec 1999 | A |
| 6021912 | Hertrampf | Feb 2000 | A |
| 6260722 | Ekkert | Jul 2001 | B1 |
| 6325226 | Krautkramer | Dec 2001 | B1 |
| 6338414 | Schellenbach | Jan 2002 | B1 |
| Number | Date | Country |
|---|---|---|
| 10-35699 | Feb 1998 | JP |
| Number | Date | Country | |
|---|---|---|---|
| 20040060893 A1 | Apr 2004 | US |
| Number | Date | Country | |
|---|---|---|---|
| Parent | 09804267 | Mar 2001 | US |
| Child | 10664869 | US |
