JP4608223B2 - Plastic cap with excellent cleanability - Google Patents

Description

The present invention relates to threaded engagement type plastic caps, and more particularly, the inner surface of the cap top plate portion and the outer ring is formed in close contact with the upper end portion of the outer surface of the container mouth walls, A Utaringu It is related with the screw engagement type plastic cap of the type by which favorable sealing performance is ensured by the effect | action of.

  Screw-engaged plastic caps are used for various purposes, and are widely used as caps for containers filled with beverages such as carbonated drinks, fruit drinks, and teas.

  Such a screw-engagement type cap has a thread that engages with a thread formed on the outer surface of the container mouth wall on the inner surface of the skirt-shaped side wall that descends from the periphery of the cap top plate. When the cap is fastened to the container filled with the content liquid, if the content liquid spilled on the threads on the outer surface of the container mouth wall adheres, the opening torque of the cap is reduced due to the generation of so-called sugar cement. It may rise, making it difficult to open the plug. Moreover, even if the content liquid does not contain sugar, when the cap is opened, there is a problem in that tea astringency or the like remains on the outer surface of the container mouth wall and the appearance of the container is impaired. For this reason, a slit for cleaning is formed in the upper part of the skirt-shaped side wall, and pressurized cleaning water is sprayed in a state where the cap is fastened to the container mouth wall, and through the slit, the skirt-shaped side wall of the cap and the container The content liquid adhering to the outer surface of the container mouth wall is removed by pouring wash water between the outer surface of the mouth wall (see Patent Document 1).

On the other hand, the inner ring of the cap top plate part is formed with an inner ring that is in close contact with the inner surface of the container mouth wall and an outer ring that is in close contact with the upper end portion of the outer surface of the container mouth wall. There is also known a screw-engagement type plastic cap that secures a good sealing property by the cooperative action of the outer ring and the outer ring (see Patent Document 2).
Japanese Patent Laid-Open No. 11-208693 JP 2002-173151 A

  However, in a screw-engagement type plastic cap in which an inner ring and an outer ring are formed on the inner surface of the cap top plate portion as in Patent Document 2, a cleaning slit is formed in the skirt-shaped side wall as in Patent Document 1. However, the content liquid adhering to the outer surface of the container mouth wall could not be removed sufficiently. In particular, there is a strong tendency that the content liquid adheres and remains on the upper surface portion of the uppermost portion of the thread formed on the outer surface of the container mouth wall. That is, recently, a large amount of content liquid has been filled in the container so that the head space of the container has a small volume, and the liquid level of the content liquid has risen to the upper end of the container mouth wall or in the vicinity thereof. In addition, in such a type of cap, a recess is formed in the lower end portion of the outer ring due to the presence of the outer ring, and the upper portion of the thread on the outer surface of the container mouth wall, which is the vicinity thereof It is thought that it is because it does not spread enough.

  In addition, in a cap provided with a tamper evident band at the lower end portion of the skirt-shaped side wall, the content liquid and the cleaning liquid are likely to remain and adhere to the inner surface of the band and the upper surface of the container jaw portion that suppresses the rise of the band. There was also a problem. If the adhering liquid is present on the upper surface of the container jaw, dirt easily adheres during storage in a warehouse or the like.

Accordingly, an object of the present invention, the type of screw engagement type plastic cap A Utaringu the inner surface of the cap top plate portion is formed to increase the washability, adhesion remaining content liquid into the outer surface of the container opening walls The object is to provide a cap that can be effectively prevented.

According to the present invention, it includes a top plate portion, a skirt-like side wall descends from the top plate peripheral edge, the said top plate inner surface, and outer ring is formed in close contact with the upper end portion of the outer surface of the container mouth wall In the plastic cap in which the inner surface of the skirt-shaped side wall is formed with a thread that engages with the thread formed on the outer surface of the container mouth wall,
The skirt-shaped side wall is provided with a cleaning cap that is provided with a cleaning slit extending in the circumferential direction at a portion located above the lower end of the outer ring.

In the present invention,
(1) The cleaning slit is formed at a position located at least 0.1 mm or more above the lower end of the outer ring,
(2) The outer ring is provided with at least one notch extending upward from the lower end ;
Is preferred.

  In the cap of the present invention, the cleaning slit provided in the skirt-shaped side wall is located above the lower end of the outer ring descending from the top plate of the cap, particularly 0.1 mm or more above, so that pressure is applied. The cleaning liquid is effectively washed by spraying the outer surface of the cap, and the content liquid adhered to the outer surface portion of the container mouth wall (for example, the uppermost portion of the thread on the container mouth wall) located near the lower end of the outer ring. Can be effectively removed. The reason why the cleaning power is enhanced by the position of such a cleaning slit is not exactly known, but the present inventors consider as follows.

  That is, when the cleaning slit is formed at a position lower than the lower end of the outer ring, the cleaning liquid that is introduced into the cap from the cleaning slit and flows into the vicinity of the lower end of the outer ring rises from below to the lower end of the outer ring. Rather than wash away the adhering liquid, the adhering liquid is sprayed on the vicinity of the outer ring, and it becomes easier to entrain air, resulting in a reduced cleaning effect, especially the outer ring. It is considered that the content liquid adhering to the outer surface of the container mouth wall remains in the vicinity of. However, according to the present invention, when the position of the cleaning slit is set above the lower end of the outer ring, the cleaning liquid introduced into the cap from the cleaning slit probably does not entrain air or the like on the outer surface of the outer ring. It flows in a laminar flow along the top of the thread on the wall of the container mouth and flows down smoothly. As a result, the content liquid adhering to this part may be effectively washed off. It is.

The present invention will be described below based on specific examples shown in the accompanying drawings.
FIG. 1 is a half sectional side view of a plastic cap of the present invention,
FIG. 2 is a view showing a side cross section of the main part of the cap of FIG. 1 together with the container mouth wall,
FIG. 3 is an enlarged view showing a slit for breaking the cap of FIG. 1 together with a cutting blade,
FIG. 4 is a half-sectional side view showing another example of the plastic of the present invention.

  Referring to FIGS. 1 and 2, the plastic cap of the present invention is composed of a top plate portion 1 and a skirt-like side wall 3 depending from the peripheral portion of the top plate portion 1.

  An inner ring 5 is formed on the inner surface of the top plate portion 1 so as to extend downward with a gap from the skirt-shaped side wall 3. An outer ring having a shorter height than the inner ring 5 is formed outside the inner ring 5. A ring 7 is formed. Further, a circumferential small protrusion 9 is formed between the inner ring 5 and the outer ring 7.

  On the other hand, a thread 11 is formed on the inner surface of the skirt-shaped side wall 3, and notches 12 extending in the height direction of the cap are formed in the thread 11 at appropriate intervals. This notch 12 serves as a flow path for a cleaning liquid to be described later.

  Moreover, a slit 15 for breaking is formed in the lower part of the screw 11 so as to leave a plurality of bridges 13 by cutting from the outer surface. That is, the breaking slit 15 is formed over the entire circumference, whereby a TE band 17 is formed on the inner surface of the skirt-shaped side wall, and the TE band 17 is formed by the bridge 13 on the skirt-shaped side wall 3. It is connected to. Also, upward flap pieces 19 are provided on the inner surface of the TE band 17 at appropriate intervals.

  Further, as shown in FIG. 2, on the outer surface of the mouth wall 50 of the container to which the cap is fastened, there is a screw 51 that is screw-engaged with the screw 11 provided on the skirt-like side wall 3. Further, a jaw 53 is formed below the screw 51.

  That is, when the cap is put on the container mouth wall 50 and rotated in the closing direction, the cap 11 is fastened by screw engagement with the threads 11 and 51, and the upper end portion of the container mouth wall 50 is connected to the inner ring 5. A seal is secured by entering the space between the outer ring 7 and the outer surface of the inner ring 5 closely contacting the inner surface of the container mouth wall 50. In addition, the circumferential small protrusion 9 is brought into close contact with the upper end of the container mouth wall 50 so that the sealing position is fixed. Further, the inner surface of the outer ring 7 is in close contact with the upper end portion of the outer surface of the container mouth wall 50. Therefore, when the cap is closed or opened, the inner ring 5 and the outer ring 7 rotate concentrically. This means that the close contact (that is, the sealing property) between the inner ring 5 and the container mouth wall 50 is effectively maintained. That is, when closing the plug, the sealing performance can be secured stably. When opening the cap, the seal does not break immediately due to the rotation of the cap, but after a certain degree of rotation, the seal is broken. The function of the TE band 17 can be sufficiently exerted (the seal breakage can be prevented before the bridge breaks).

  The TE band 17 has a so-called tamper evidence (opening history certification) function, and is used for prevention of mischief and quality assurance of contents. That is, when the cap fastened to the container mouth wall 50 is rotated in the opening direction, the cap rises along the container mouth wall 50, and is provided on the inner surface of the TE band 17 with the rise. The flap piece 19 is in contact with the lower surface of the jaw 53 formed on the outer surface of the container mouth wall 50, and therefore the rise of the TE band 17 is restricted. As a result, when the cap continues to rotate in the opening direction, the bridge 13 connecting the TE band 17 is broken, and the TE band 17 is peeled off from the cap. As a result, it is shown that the cap from which the TE band 17 has been peeled has already been opened, or that the seal has already been broken, and the general consumer can recognize the opening history. It is.

  The skirt-like side wall 3 is provided with a cleaning slit 20 extending in the circumferential direction. In the present invention, the cleaning slit 20 is located above the lower end of the outer ring 7. In particular, it is preferable that the distance L between the cleaning slit 20 and the lower end of the outer ring 7 is set to at least 0.1 mm or more.

  That is, when the cap is fastened to the mouth wall 50 of the container filled with the contents liquid, the contents liquid spills out and the contents are formed between the outer surface of the container mouth wall 50 and the inner surface of the skirt-like side wall 3 of the cap. If the liquid is present between the threads 11 and 51, it may be difficult to open the plug due to the production of sugar cement or the like. In particular, recently, there is a tendency to fill a large amount of the content liquid so as not to leave a head space in the container. Accordingly, the cleaning slit 20 as described above is provided, and pressurized cleaning water (for example, shower water) is sprayed from the outer surface of the cap in a state where the cap is fastened, and the inside of the cap (container mouth wall 50 is discharged from the cleaning slit 20. Between the skirt-like side wall 3 and the skirt-like side wall 3), and the attached content liquid is washed away. The washing water passes between the threads 11 and 51, passes through the notch 12 formed in the threads 11, and flows downward. When cleaning is performed in this way, even if the cleaning between the threads 11 and 51 is sufficiently performed, in particular, the vicinity of the lower end of the outer ring 7 (for example, the thread 51 formed on the container mouth wall 50). Of the top surface of the uppermost part) is likely to be insufficiently cleaned. This is because a recess is formed in the lower end portion of the outer ring 7 and the cleaning liquid does not spread sufficiently. If the content liquid adheres and remains in such a portion, the appearance of the container when the cap is removed is impaired.

  In the present invention, by setting the position of the cleaning slit 20 above the lower end of the outer ring 7 as described above, the cleaning water can be sufficiently distributed in the vicinity of the lower end of the outer ring 7. The content liquid adhering to the vicinity of the upper surface of the uppermost part of the strip 51 can be washed away effectively. That is, by positioning the cleaning slit 20 above the lower end of the outer ring 7, the cleaning water introduced from the slit 20 flows in a laminar flow along the outer surface of the outer ring 7. This is enough to reach the vicinity of the lower end.

  The cleaning slits 20 are usually formed at a suitable interval by post-processing such as cutting using a cutter, and the cleaning water is distributed throughout the cap. The distance d or the length d of each cleaning slit 20 may be set to a value that does not cause deformation due to a decrease in strength of the cap skirt-like side wall 3, for example, 1.5 to 4.0 mm. It is preferable to do this. Further, the clearance t of the cleaning slit 20 may be large enough to allow the pressurized cleaning water to pass through.

  Further, in the present invention, as shown in FIG. 3, the breaking slit 15 formed on the upper surface of the TE band 17 is opened from the outer surface of the lower part of the skirt-like side wall at the opening angle α of 15 to 45 degrees. It is preferable that the cutting blade 40 having the above-mentioned is formed by acting, so that it is possible to effectively avoid the residual adhesion of the content liquid flowing into the slit 15 during cleaning, and the amount of cleaning liquid introduced from the slit 15 In addition, the drying effect is enhanced, and the remaining of the liquid on the upper surface of the jaw portion 53 of the container mouth wall 50 facing the slit 15 and the inner surface of the TE band 17 can be effectively prevented. For example, when the upper and lower surfaces of the breaking slit 15 are provided in parallel to each other (α = 0) or when α is smaller than the above range, the content liquid and the cleaning liquid are likely to adhere and remain in the breaking slit 15. In addition, the pressure of the cleaning liquid introduced into the cap from the breaking slit 15 may be reduced, and the cleaning effect may be reduced. Further, when α is larger than the above range, the breaking slit 15 itself becomes larger than necessary.

  The opening angle β of the outer side portion following the tip portion of the breaking slit 15 is preferably smaller than the opening angle α, and in particular by applying a cutting blade having an opening angle β of 10 to 25 degrees. Is formed.

  The opening angle β of the outer side portion following the tip portion of the breaking slit 15 is preferably smaller than the opening angle α, and the opening angle β is particularly preferably in the range of 10 to 25 degrees. That is, by making the opening angle β smaller than the opening angle α, it is possible to further increase the cleaning pressure of the cleaning liquid introduced through the slit 15. In particular, by setting the opening angle β within the above range, cleaning is performed. Efficiency can be optimized.

  The plastic cap of the present invention described above is not limited to the structure shown in FIGS. 1 and 2, and various design changes are possible. For example, as shown in FIG. 4, the outer ring 7 is provided with notches 45 at regular intervals, and the cap is fastened between the lower end portion of the outer ring 7 and the outer surface of the container mouth wall 50. The minute space to be formed becomes easier to clean through the notch 45. Thereby, the storage of the content liquid in such a minute space can be avoided more effectively.

It is a half section side view of the plastic cap of this invention. It is the figure which showed the principal part side cross section of the cap of FIG. 1 with the container opening part wall. It is a figure which expands and shows the slit for a fracture | rupture of the cap of FIG. 1 with a cutting blade. It is a half section side view showing other examples of the plastic cap of the present invention.

Explanation of symbols

3: Skirt-shaped side wall 5: Inner ring 7: Outer ring 11: Cap thread 13: Bridge 15: Breaking slit 17: TE band 50: Container mouth wall 51: Container mouth wall thread 53: Container mouth Jaw of the wall

Claims (3)

A top plate portion, and a skirt-like side wall descends from the top plate peripheral edge, the said top plate inner surface, the outer ring in close contact with the upper end portion of the outer surface of the container mouth walls are formed, of the skirt-like side wall On the inner surface, in the plastic cap formed with a thread that engages with a thread formed on the outer surface of the container mouth wall,
The plastic cap, wherein the skirt-like side wall is provided with a cleaning slit extending in a circumferential direction at a portion located above the lower end of the outer ring.   2. The plastic cap according to claim 1, wherein the cleaning slit is formed at a position located at least 0.1 mm or more above a lower end of the outer ring.   The plastic cap according to claim 1 or 2, wherein the outer ring is provided with at least one notch extending upward from a lower end.

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