TWI441757B - Synthetic resin cap, closing device, beverage-containing closing device, and method of manufacturing synthetic resin cap - Google Patents

Description

Synthetic resin cap, closing device, closure device containing beverage, and manufacturing method of synthetic resin cap

The present invention relates to a synthetic resin cover for closing a mouth of a container, a closing device using the cover, a closing device for containing a beverage, and a manufacturing method of the synthetic resin cover.

In the past, a synthetic resin cover having a top plate portion and a cylindrical portion that hangs from the periphery thereof and having a washing water introduction hole formed therein is generally used (see, for example, Patent Document 1).

The synthetic resin cap can introduce the washing water into the inside through the washing water introduction hole to wash the mouth of the container.

In recent years, a synthetic resin cover which prints information such as characters, symbols, graphics, and the like on a top plate portion by a lithography method or the like (for example, a product name or a company name) has been used. In order to prevent peeling of the printing, surface treatment is sometimes applied to the top plate portion before printing.

[Patent Document 1] Japanese Patent Laid-Open Publication No. 2004-244074

However, in the case of the synthetic resin cover described above, the washing water introduced into the interior may be insufficient, and the washing of the container mouth may be insufficient.

The present invention has been made in view of the above circumstances, and an object of the invention is to provide a synthetic resin cover, a closing device, a closing device for containing a beverage, and a method for producing the synthetic resin cover, which can sufficiently clean the mouth of the container.

The present invention provides a synthetic resin cover including a top plate portion and a cylindrical portion that hangs from a peripheral edge thereof, and a washing water introduction hole is formed in the tubular portion, and printing is applied to the top plate portion, and at least The outer surface portion of the cylindrical portion of the peripheral portion of the washing water introduction hole and the upper surface of the top plate portion are surface-treated only on the upper surface of the top plate portion, thereby improving wettability.

In the synthetic resin cover, a contact angle of 10 μL of the water droplets on the low wettability portion of the outer portion of the cylindrical portion including at least one of the washing water introduction holes is 10 μL above the top plate portion. The contact angle is large, and the difference can be more than 30 degrees.

The contact angle of 10 μL of the low-moisture portion of the water droplet outside the tube portion may be 95 degrees or more.

According to the present invention, there is also provided a closing device comprising the synthetic resin cap and a container capable of attaching the synthetic resin cap to the mouth.

According to the present invention, there is also provided a closure device comprising the synthetic resin cap and a container capable of attaching the synthetic resin cap to the mouth, and the container is filled with a beverage.

According to the present invention, there is also provided a method for producing a synthetic resin cap having a top plate portion and a tubular portion that hangs from a peripheral edge thereof, wherein the tubular portion is formed with a washing water introduction hole, and printing is applied to the top plate portion Further, in the outer surface portion of the tubular portion including at least one peripheral portion of the washing water introduction hole and the upper surface of the top plate portion, only the upper surface of the top plate portion is surface-treated, thereby improving wettability.

The surface treatment can also be a flame treatment.

In the synthetic resin cover of the present invention, since the surface of the top plate portion is only surface-treated, the wettability is improved, so that the wettability of the outer surface of the tubular portion is relatively low. Therefore, the washing water supplied to the outside of the lid can easily flow into the inside of the lid through the washing water introduction hole. Thereby, the mouth of the container can be sufficiently washed.

1 and 2 show an example of a closing device according to the present invention, which is composed of a container 20 and a synthetic resin cover 1 attached to the mouth portion 21.

As the container 20, a synthetic resin such as polyethylene terephthalate (PET), glass, metal, or the like can be used. The mouth portion 21 is a cylindrical portion to which the cover 1 is attached, and a male thread 22 is formed on the outside thereof.

The lid 1 is provided with a lid body 4 having a top plate portion 2 and a tubular portion 3 depending from the periphery thereof.

The tubular portion 3 is divided into a main portion 8 by a horizontal scribing line (weakening line) 6, and a tamper evidence ring 9 (TE ring portion) which is coupled to the lower end of the main portion 8 by a plurality of bridging portions 7. ).

Inside the main portion 8, a screw portion 10 having a shape of a male thread 22 along the mouth portion 21 of the container is formed. On the outer surface of the main portion 8, a knurl 16 is formed which is a convex portion extending in the downward direction (vertical direction in the drawing). The embossing 16 is formed in a plurality of intervals in the circumferential direction of the cover 1.

One or a plurality of washing water introduction holes 17 are formed in the upper portion of the tubular portion 3, so that the washing water can be introduced into the inside of the lid 1. The washing water introduction hole 17 preferably has a slit shape extending in the circumferential direction of the lid 1.

The length of the washing water introduction hole 17 extending in the circumferential direction of the lid may be, for example, 0.5 to 5 mm. The width (gap width) of the washing water introduction hole 17 in the direction of the lid 1 axis can be, for example, 0.01 to 0.1 mm.

In the lid 1, the outer surface 3a of the tubular portion 3 including at least one peripheral portion of the washing water introduction hole 17 and the upper surface 2b of the top plate portion 2 only improve the wettability of the upper surface 2b of the top plate portion 2. Thereby, the upper surface 2b of the top plate portion 2 is higher in wettability than the low wettability portion of the outer surface 3a of the tubular portion 3.

The upper surface 2b of the top plate portion 2 can have higher wettability than the outer surface 3a of the tubular portion 3.

The wettability was evaluated by visually indicating a contact angle of 10 μL supplied to the surface of the measurement object. As shown in FIG. 4, the contact angle means the contact angle α of the water droplets 34 on the measurement target surface 33. The lower the wettability, the larger the contact angle.

The upper surface 2b of the top plate portion 2 can be improved in wettability by flame treatment or the like which will be described later. The contact angle of the upper surface 2b of the top plate portion 2 can be adjusted to less than 95 degrees.

The contact angle of the low wettability portion of the outer surface 3a of the tubular portion 3 can be, for example, 95 degrees or more (preferably 100 degrees or more).

Further, when the contact angle is measured, it is preferable to take three or more samples, preferably five or more. It is preferable to calculate the average value of these. The contact angle of the upper surface 2b of the top plate portion 2 can be measured in the portion where no printing 15 is provided. Further, since the embossing 16 is formed on the outer surface 3a of the tubular portion 3, the contact angle of the outer surface 3a of the tubular portion 3 may be as large as 10 to 30 degrees as compared with the case where the embossing 16 is not affected.

The contact angle of the low wettability portion of the outer surface 3a of the tubular portion 3 is larger than the contact angle of the upper surface 2b of the top plate portion 2, and the difference is preferably 30 degrees or more, more preferably 40 degrees or more. When the difference is less than the range, it is likely that the washing water is not easily introduced into the washing water introduction hole 17.

A plurality of tabs 11 are provided on the inner surface of the TE ring portion 9. The joint 11 is a locking projection that is locked to the bulging portion 23 of the container mouth portion 21 when the lid 1 is opened to prevent the movement of the TE ring portion 9. The joint 11 is formed in a substantially rectangular plate shape which can be undulated and formed in the circumferential direction.

On the lower surface 2a of the top plate portion 2, an annular inner seal projection 12 for inserting into the mouth portion 21 of the container is formed, and an annular open end seal projection 13 for contacting the open end of the container mouth portion 21 is formed, and is used for contact with The outer side of the outer surface of the container mouth 21 seals the projection 14.

As shown in FIG. 2, printing 15 is applied to the upper surface 2b of the top plate portion 2.

Printing 15 means a character, a symbol, a graphic, etc. (for example, a product name, a company name), and can be lithographically printed (for example, offset printing), gravure printing, letterpress printing, ink jet (ink jet). Law is formed.

Examples of the synthetic resin material constituting the lid 1 include polypropylene and polyethylene.

Next, an example of a method of manufacturing the cover 1 will be described.

After the cover 1 is formed, a surface treatment as shown below is applied to the upper surface 2b of the top plate portion 2.

Fig. 3 shows a flame treatment apparatus for treating the upper surface 2b of the top plate portion 2. This processing apparatus includes a conveyor 31 that transports the cover 1 and a burner 32 that emits a flame 18.

The cover 1 is conveyed by the conveyor 31 in a direction perpendicular to the paper surface, and the upper surface 2b of the top plate portion 2 is exposed to the flame 18. Thereby, the upper surface 2b is heated and its surface state changes, and the wettability is improved.

At this time, the flame 18 is adjusted to perform the treatment of the flame 18 only on the upper surface 2b of the top plate portion 2. That is, in order to prevent the flame 18 from flowing to the outer surface 3a of the tubular portion 3, the flame 18 is adjusted so that the width W1 of the flame 18 emitted from the burner 32 is substantially equal to the diameter D1 of the top plate portion 2.

By only performing the flame treatment on the upper surface 2b of the top plate portion 2, the cover 1 which only improves the wettability of the upper surface 2b can be obtained.

Next, the printing 15 is applied to the upper surface 2b of the top plate portion 2 by a lithography method (for example, offset printing method), a gravure printing method, or the like. Since the upper surface 2b has been subjected to flame treatment, the printing 15 is strongly adhered, and peeling of the printing 15 is not easily caused.

In order to wash the outside of the mouth portion 21 of the container 20 to which the lid 1 is attached, it is necessary to supply the washing water to the outside of the lid 1. The washing water flows into the inside of the lid 1 through the washing water introduction hole 17, and flows out from the lid 1 outside the mouth portion 21. Thereby, the mouth portion 21 is washed.

In the lid 1, since the wettability of the low wettability portion of the outer surface 3a of the tubular portion 3 is lower than the upper surface 2b of the top plate portion 2, the washing water supplied to the outside of the lid 1 can be easily introduced through the washing water. The hole 17 flows into the inside of the cover 1. Therefore, the mouth portion 21 can be sufficiently washed.

By making the wettability of the outer surface 3a of the tubular portion 3 low, the washing water can be easily introduced into the washing water introduction hole 17, although the reason is not understood, but it is presumed as follows.

When the wettability of the outer surface 3a is high, since the washing water flows down so as to cover the outer surface 3a, it is not easy to flow into the inside of the lid 1 from the washing water introduction hole 17. On the other hand, when the wettability of the outer surface 3a is low, it is conceivable that the washing water becomes small water droplets, and it is easier to flow into the inside of the lid 1 from the washing water introduction hole 17.

The closing device is filled with a beverage such as a juice drink, a coffee beverage, or a carbonated beverage, and is attached to the mouth, thereby being a closing device filled with a beverage filled with a beverage.

Further, in the surface treatment method on the top surface portion, in addition to the flame treatment method, there are a plasma treatment method, an odor treatment method, a corona discharge treatment method, and the like.

Further, when the influence of the knurling 16 on the contact angle is very large, the rising portion caused by the knurling 16 can be subtracted, and then the top plate portion 2 and the tubular portion 3 can be compared. In this case, the contact angle of the low wettability portion of the outer surface 3a of the tubular portion 3 is preferably 1 degree or more, more preferably 5 degrees or more, larger than the contact angle of the upper surface 2b of the top plate portion 2.

[Examples] (Example 1)

The cover 1 shown in Figs. 1 and 2 was produced as follows.

After the cover 1 is formed, the upper surface 2b of the top plate portion 2 is exposed to the flame 18 using the flame treatment apparatus shown in FIG.

At this time, by making the width W1 of the flame 18 substantially equal to the diameter D1 of the top plate portion 2, the flame 18 is treated only on the upper surface 2b of the top plate portion 2.

The wettability of the upper surface 2b of the top plate portion 2 and the outer surface 3a of the tubular portion 3 was evaluated by the following method. In other words, after the lid 1 is placed such that the measurement target surface (the upper surface 2b or the outer surface 3a) is horizontal, 10 μL of water is supplied to the measurement target surface. The contact angle of the water droplets immediately after the supply was measured. The contact angle of the outer surface 3a of the tubular portion 3 is measured at the peripheral portion of the washing water introduction hole 17.

For the measurement of the contact angle, a contact angle and a wettability measuring device FTA125 (manufactured by First Ten Angstroms Co., Ltd.) were used. Table 1 shows the results.

(Comparative Example 1)

As shown in Fig. 5, the lid was treated in the same manner as in Example 1 except that the width of the flame 43 emitted from the burner 42 was made much larger than the diameter D1 of the top plate portion 2, and the contact angle was measured. Table 1 shows the results.

(Examples 2, 3, Comparative Example 2)

The lid was treated in the same manner as in Example 1 except that the flame width of the burner of the flame treatment apparatus was adjusted so that the contact angle between the tubular portion and the top plate portion was the value shown in Table 2, and the contact angle was measured. The number of samples was taken as 5, and Table 2 shows the average.

Further, with respect to the lids used in the above respective examples and comparative examples, the contact angle between the top plate portion and the cylindrical portion was measured without flame treatment, the contact angle on the top surface of the top plate portion was 85.13 degrees, and the contact angle outside the cylindrical portion was 113.89 degrees ( Both are average of 5 samples).

The lids of the examples and the comparative examples were attached to a container 2 to which dyed water adhered to the outside of the mouth portion 21, and water was sprinkled from the top for 3 minutes.

When the lid 21 was opened and the mouth portion 21 was confirmed, it was found that the dyed water remained in the mouth portion 21 in the case of the comparative example, but in the examples, almost no residual dye water was left.

As a result of the above, it is understood that in the embodiment in which the outer surface 3a of the tubular portion 3 is not affected by the flame treatment, the wettability of the outer surface 3a of the tubular portion 3 can be lowered, and the washing performance can be improved.

1. . . cover

2. . . Roof section

2b. . . Above

3. . . Tube

3a. . . outside

4. . . Cover body

6. . . Horizontal line

7. . . Bridge

8. . . Main department

9. . . Tightening the ring

10. . . Screw part

11. . . Connector

12. . . Inner seal protrusion

13. . . Open end seal projection

14. . . Outer seal protrusion

15. . . print

16. . . Rolling

17. . . Washing water introduction hole

18, 43. . . flame

20. . . container

twenty one. . . Mouth

twenty two. . . Male thread

twenty three. . . Segment

31. . . Conveyor

32, 42. . . burner

33. . . Measuring object surface

34. . . Water droplets

D1. . . Top plate diameter

W1. . . Width of flame

α. . . Contact angle

BRIEF DESCRIPTION OF THE DRAWINGS Figure 1 is a cross-sectional view showing a closing device using an example of a cover of the present invention.

Fig. 2 is a plan view showing the cover shown in Fig. 1.

Fig. 3 is a schematic block diagram showing a flame treatment apparatus which can be used for the manufacture of the lid shown in Fig. 1.

Figure 4 is an explanatory view of the contact angle.

Fig. 5 is a schematic block diagram showing a flame treatment apparatus used in a comparative example.

1. . . cover

2. . . Roof section

2b. . . Above

3. . . Tube

3a. . . outside

4. . . Cover body

6. . . Horizontal line

7. . . Bridge

8. . . Main department

9. . . Tightening the ring

10. . . Screw part

11. . . Connector

12. . . Inner seal protrusion

13. . . Open end seal projection

14. . . Outer seal protrusion

16. . . Rolling

17. . . Washing water introduction hole

20. . . container

twenty one. . . Mouth

twenty two. . . Male thread

twenty three. . . Segment

Claims (5)

A synthetic resin cover comprising a top plate portion and a tubular portion hanging from a peripheral edge thereof, wherein the tubular portion is formed with a washing water introduction hole, and printing is applied to the top plate portion, wherein at least one of the cleaning is included In the outer surface portion of the cylindrical portion of the peripheral portion of the water introduction hole and the upper surface of the top plate portion, only the upper surface of the top plate portion is surface-treated, thereby improving wettability; and at least one peripheral portion of the washing water introduction hole is included The outer portion of the tubular portion has a low wettability portion which is lower in wettability than the upper surface of the top plate portion; the contact angle of the water droplet on the low wettability portion is larger than the contact angle of the water droplet on the top plate portion. The gap is more than 30 degrees. The synthetic resin cap according to claim 1, wherein the contact angle of the water droplets to the low wettability portion is 95 degrees or more. A closing device comprising a synthetic resin cap according to claim 1 and a container capable of attaching the synthetic resin cap to a mouth. A closure device for containing a beverage, comprising: a synthetic resin cap according to claim 1; and a container capable of attaching the synthetic resin cap to a mouth, and filling the container with a beverage. A method for producing a synthetic resin cap comprising a top plate portion and a tubular portion that hangs from a peripheral edge thereof, wherein a washing water introduction hole is formed in the tubular portion, and printing is applied to the top plate portion. : in an outer portion of the tubular portion including at least one peripheral portion of the washing water introduction hole and an upper surface of the top plate portion, only the top portion of the top plate portion is flame-treated Performing a surface treatment to improve the wettability of the top portion of the top plate portion; during the flame treatment, adjusting the flame such that the width of the flame is substantially equal to the diameter of the top plate portion, thereby preventing the flame from affecting the outer surface of the cylindrical portion The outer surface portion of the cylindrical portion including at least one peripheral portion of the washing water introduction hole forms a low wettability portion having a lower wettability than the upper surface of the top plate portion.