JPH0326101Y2 - - Google Patents

Description

[Detailed description of the invention] This invention relates to a filled and sealed container capable of absorbing negative pressure.
More specifically, the present invention relates to a filled and sealed container that does not cause uneven concave deformation in the body after being filled with a high temperature liquid and sealed and cooled.

Acidic liquid foods such as fruit juices or beverages such as coffee are usually heated at high temperatures, e.g.
After heat sterilization at 90°C, the container body is filled (in this specification, filling includes cases in which a head space is left and cases in which it is not left), and then sealed with a lid. In this case, during the cooling process after sealing, the volume of the liquid content decreases, and if there is a head space, the water vapor condenses in the head space, resulting in a negative pressure inside the sealed container (i.e., a pressure lower than atmospheric pressure, e.g. 30-40mmHg).

Therefore, the body of the container body is made of a material of relatively low rigidity, which has the advantage of low material cost, e.g.
~100 μm thick coated metal foil (made of aluminum, tin-plated steel plate, etc.) alone, or a laminate of plastic film-aluminum foil-plastic film, or plastic film-paper material-plastic film-aluminum foil-plastic film When the body is made of a laminate or the like, there is a problem in that the internal negative pressure causes the body to dent unevenly, spoiling the appearance and reducing the commercial value.

The present invention aims to solve the problems of the prior art described above.

In order to achieve the above object, the present invention provides a filled and sealed container in which a container body having a cylindrical body is filled with a high temperature liquid and then sealed with a lid member.
The present invention provides a filled and sealed container capable of absorbing negative pressure, characterized in that a narrow annular portion that is easily flexible is formed in the body before filling.

The present invention will be described below with reference to the drawings which are examples.

In FIG. 1, 1 is a sealed container, and the body 3
A container body 2 consisting of a bottom portion 4 is filled with a content 5 consisting of a high temperature (e.g. 70 to 90°C) liquid food (including cases containing solids), leaving a head space 6. , shows the state immediately after being sealed with the lid part 7.

The body portion 3 is provided with a thin and easily flexible narrow annular portion 8 formed by local rolling. The inner surface of the annular portion 8 is on the same plane as the inner surfaces of the upper trunk main portion 3a and the lower trunk, and the outer surface of the annular portion 8 is the bottom surface of the recess 9.

The body part 2 is made of a material that can form the annular part 8 without causing deformation such as warping by local rolling, but more preferably, in order to save material, it is made of a material with relatively low rigidity (self-contained material before rolling). It has shape-retaining properties, but is easily bent when pressed with fingers). Furthermore, it is desirable that the material is heat-sealable to the bottom part 4 and the lid part 7.

Such materials include polyethylene (outer layer:
(thickness approx. 20 to 70 μm) - Aluminum foil (middle layer: approx. 7 to 100 μm thick) - Polyethylene (inner layer: approx. thickness
40 to 100 μm), or polyethylene (outer layer: approximately 20 to 70 μm thick) - kraft paper (outer middle layer: approximately 100 to 500 μm thick) - polyethylene (center middle layer: 20 to 50 μm thick) Examples include a laminate of aluminum foil (inner intermediate layer: about 7 to 50 μm thick) and polyethylene (inner layer: about 40 to 100 μm thick), or a single polyethylene terephthalate sheet about 100 to 500 μm thick. Note that polyethylene in the laminate may be replaced with polypropylene.

The body 3 is usually formed by rolling blanks made of these materials and heat-sealing the overlapping side edges, but the above local rolling is performed on the blank before the body 3 is formed. Alternatively, it may be performed after the above heat sealing. However, in the former case, it is necessary to ensure airtightness by filling the recesses formed by rolling inside the overlapping side edges with polyethylene, polypropylene, or the like.

As shown in FIG. 2, by preferentially bending the annular portion 8 inward to absorb the internal negative pressure generated as the contents 5 are cooled, the upper body main portion 3a and the lower body main portion 3b The inner volume of the annular portion 8 is absorbed by the inner volume of the annular portion 8, which approaches each other without being unevenly deformed, reducing the internal volume. Main part 3a, 3b
The thickness is preferably about 15 to 70%, and more preferably about 30 to 60%.

If it is larger than about 15%, it will be difficult for the annular part 8 to preferentially bend inward, while if it is smaller than about 70%, defects such as warping and curvature will easily occur during formation due to local rolling. . Further, the annular portion 8 is connected to the upper trunk main portion 3a when the container body 2 is erected.
It is necessary to have a thickness that prevents the annular portion 8 from tilting or shrinking, that is, the container body 2 has a self-shape retaining property.

Further, the width of the annular portion 8, that is, the height in the axial direction is preferably about 3 to 10 mm. Widths wider than approximately 10 mm are usually not necessary to absorb internal negative pressure, and may conversely impair the self-retention properties of the container body 2, and may also reduce the appearance after absorbing negative pressure and bending inward. This is because it will cause damage. On the other hand, if it is narrower than about 3 mm, the internal negative pressure cannot be absorbed sufficiently, so
This is because there is a possibility that uneven dents may be formed in the area b.

In addition, in the step before sealing, it is preferable to apply a slight force in the axial direction to the body part as necessary to create a starting point for bending in the annular part 8.

The sealed container 11 in FIG. 3 shows another embodiment of the present invention, and the parts having the same reference numerals as in FIG. 1 indicate the same parts. Upper body main part 13a and lower body main part 13 of the body 13 forming the container body 12
A cylindrical body 18' made of a flexible material (preferably approximately the same type as the main body part, but thinner in thickness) is attached to the inner surface of each of the spaced apart ends 13a ₁ and 13b ₁ of b.
The difference from the sealed container 1 is that the annular portion 18 is formed by heat-sealing. The properties required for the annular portion 18 and its effects are as follows:
It is similar to Note that when the cylindrical portion 18' includes metal foil, it is desirable to protect its end surface from the contents with paint or the like (not shown).

The present invention is not limited to the above embodiments; for example, the annular portion may be directly joined to the lid portion without providing the upper body main portion. Also, the contents may be filled without leaving any head space. In this case as well, the annular portion absorbs internal negative pressure (vacuum) due to volume reduction due to cooling of the contents by bending inward.

In the filled and sealed container of the present invention, a flexible annular portion is formed in the body before filling, so when the high temperature liquid cools and the inside becomes negative pressure, the annular portion preferentially bends inward. As a result, the body portion above and below the annular portion move closer to each other, lowering the height of the body and reducing the internal volume, thereby absorbing negative pressure. Therefore, even when the body is made of a material with relatively low rigidity, the filled and sealed container of the present invention has the effect that uneven dents are unlikely to occur in the body after cooling, and a decrease in commercial value can be prevented. play.

Since the annular portion is narrow, it has the advantage that there is no risk of impairing the self-shape retention of the container body before filling, and that the appearance of the filled and sealed container after bending is hardly impaired.

[Brief explanation of the drawing]

FIG. 1 is a vertical sectional view showing the filled and sealed container according to the first embodiment of the present invention in a state immediately after being sealed; FIG. 2 is a longitudinal sectional view showing the filled and sealed container of FIG. 1 in a state after cooling; FIG. 3 is a longitudinal sectional view showing a filled and sealed container according to a second embodiment of the present invention immediately after being sealed. 1...Filled sealed container, 2...Container body, 3...
Body part, 5... Contents (liquid), 8... Annular part, 1
1...Filled sealed container, 12...Container body, 13...
... body part, 18 ... annular part.

Claims (1)

[Scope of utility model registration request] In a filled and sealed container in which a container body having a cylindrical body is filled with a high-temperature liquid and then sealed with a lid member, a narrow annular portion that is easily bent is formed in the body before filling. A filled and sealed container capable of absorbing negative pressure.