JPH11278434A - Method for packaging article - Google Patents

Abstract

PROBLEM TO BE SOLVED: To package an article with a pressure raised inside a packaging material by vaporizing a liquid or solid vaporizable substance after the liquid or solid vaporizable substance which vaporizes at normal temperature with normal pressure is inserted inside the packaging material together with the article and the packaging material is sealed. SOLUTION: Two tennis balls 1 with an internal pressure of 186 kPa for example and dry ice 2 taken out of a cold insulating container are put in a steel can 10 with an upper part opened, and a lid material 3 is put over the upper opening and caulked for hermetically sealing the steel can 10. If this is left under normal temperature with normal pressure, the dry ice 2 vaporizes to allow the inside of the steel can 10 to be kept at a high pressure. This packaging method facilitates operation since a vaporizable substance such as dry ice 2 may be only packaged with an article in a packaging material. In addition, since the vaporizable substance such as the dry ice 2 is relatively inexpensive, packaging can be done at a low cost.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for packaging an article, and more particularly to a method for packaging an article with high pressure inside the packaging material with simple workability and low cost.

[0002]

2. Description of the Related Art Unlike other hollow ball balls, a rigid tennis ball does not require external gas filling. That is,
It is manufactured by filling the inside with gas in the manufacturing process. Since the rigid tennis ball manufactured in this way has a higher internal pressure than the outside air pressure, the amount of gas inside the material is small, but it passes through the minute gap of the material and the minute gap at the joint of the material. Leaks out with the passage of time. Therefore,
After the tennis ball is manufactured, it is packaged by a packaging material in which the inside is in a high pressure state that is substantially equal to the internal pressure of the tennis ball.

[0003] As a method of packaging an article with the inside of the packaging material in a high-pressure state, for example, a method of pressurizing or lowering the temperature in a chamber and packaging the article in the chamber (chamber method), a packaging material A gas generating agent is enclosed together with the article, and after packaging, the gas generating agent is chemically reacted to make the inside of the packaging material pressurized (gas generating agent method). A special pressurizing valve is attached to the packaging material in advance. In addition, there is a method of externally filling the inside of the packaging material with a pressurized gas through a pressurizing valve after packaging (external pressurization method). Of these, a chamber type is often used for packaging hard tennis balls (hereinafter, also simply referred to as tennis balls).

[0004]

However, in the case of the above-mentioned conventional chamber system, continuous operation cannot be performed in a batch process. Therefore, the interior of the chamber must be brought into a high pressure state or a low temperature state every time a packaging operation is performed. Pressurizing and depressurizing (returning to normal pressure) or cooling and raising the temperature (returning to normal temperature) are repeated, which causes a problem that workability is poor. Further, since the packaging material (for example, a can) itself has to be taken into the chamber, as the number of tennis balls to be packaged increases, the chamber itself becomes very large and the production cost increases. In addition, since equipment such as a chamber is designed in accordance with the size of the packaging material, the equipment must be changed according to a change in the packaging scale. Also, the chamber needs a robust chamber that can withstand high pressure,
Since a large amount of energy is required to lower the temperature in the chamber, the manufacturing cost increases.

In the case of the gas generating system, azodicarbonamide, azobis / isobutyronitrile and the like are usually used as the gas generating agent. However, these gas generating agents are very expensive, and these gas generating agents are used. Since most of the generator basically generates gas by a chemical reaction due to heating, the entire packaging material must be heated after packaging, which increases the cost of heating. In addition, when a synthetic resin can container or film is used as a packaging material, adverse effects such as deformation of the packaging material are caused. In addition, not only gas but also water is generated at the same time due to the chemical reaction, and the moisture adversely affects the packaged articles. In particular, when the article is a tennis ball, it affects the physical properties of the tennis ball.

Further, in the case of the external pressurizing method, it is necessary to previously provide a special pressurizing valve with a special pressurizing valve on the packaging material, which increases the cost. Further, there is a possibility that gas may escape from the pressurizing valve, and such a method is not adopted when the packaging material is a can.

[0007] The present invention has been made in view of the above-mentioned circumstances, and the inside of a packaging material can be formed at a low cost with a simpler operation than before and without adversely affecting the physical properties of an article to be packaged. It is an object of the present invention to provide a packaging method capable of packaging articles in a high-pressure state, and is particularly suitable for packaging of a rigid tennis ball in which a gas having a pressure higher than the atmospheric pressure is contained. This allows the balls to be packaged at a low cost at one time.

[0008]

In order to solve the above-mentioned problems, the present invention is characterized in that, in claim 1, a liquid or solid vaporizable substance which vaporizes at normal temperature and normal pressure is inserted together with an article into a packaging material. The present invention also provides a method for packaging an article, characterized in that after the packaging material is hermetically sealed, the liquid or solid vaporizable substance is vaporized to make the interior of the packaging material pressurized.

The liquid or solid vaporizable substance which is vaporized at normal temperature and normal pressure is usually stored in a liquid or solid state in a cold storage container until the packaging operation is performed. Take it out and insert it into the packaging together with the goods. Specific examples of the liquid or solid vaporizable substance that vaporizes at normal temperature and normal pressure include dry ice and liquid nitrogen. In addition, the vaporization of the liquid or solid vaporizable substance is usually performed by sealing the packaging material and then leaving the packaged product under a normal temperature and normal pressure atmosphere. In addition, although it is not necessary to perform positively, vaporization can be promoted by heating the package to the extent that the packaging material is not deformed.

The use of the packaging method of the present invention does not require the use of conventional equipment for gas filling or the need to perform special processing such as providing a valve on the packaging material. Since the vaporizable substance such as liquid nitrogen is relatively inexpensive, and the operation is only to pack the vaporizable substance such as dry ice or liquid nitrogen with the packaging material together with the article, the article can be easily manufactured at low cost. Packaging can be performed with the pressure inside the packaging material increased. In addition, a vaporizable substance such as dry ice or liquid nitrogen does not generate moisture due to vaporization, and thus does not adversely affect the physical properties of the article.

It is preferable to use a solid vaporizable substance such as dry ice which vaporizes at normal temperature and normal pressure rather than a liquid vaporizable substance such as liquid nitrogen which vaporizes at normal temperature and normal pressure. This is because the solid vaporizable substance is easier to handle and easier to measure, so that the internal pressure of the packaging material can be easily controlled to a predetermined high pressure. Also, when left at room temperature, dry ice vaporizes more slowly than liquid nitrogen, and does not violently evaporate before it is taken out of the cool container and inserted into the packaging material. It is preferable to use a solid vaporizable substance such as ice which vaporizes at normal temperature and normal pressure.

Various types of packaging materials can be used according to the size and shape of the articles to be packaged. For example, canned containers and bag-shaped films can be used. When the article to be packaged is, for example, a tennis ball, a conventionally used synthetic resin or metal can container or a film having gas impermeability and heat sealability can be used. As a film having gas-impermeable and heat-fusible properties, usually, a gas-impermeable film such as a polyester film or an aluminum film and a heat-fusible film such as a polyethylene film or a polypropylene film are laminated, A laminated film having at least one surface layer is used.

When a can is used, a gas generating substance such as dry ice or liquid nitrogen taken out of a cold storage container is used for tennis balls in a working atmosphere at normal temperature and normal pressure without using special equipment such as a high-pressure chamber. After being inserted into the can container, a lid member is joined to the insertion port by caulking, fusion or the like, and sealed. In addition, when using a film having gas impermeability and heat fusibility, usually, a required portion of the film is laminated in advance and heat-fused to form the film into a bag, and in a working atmosphere at normal temperature and normal pressure, After a substance for gas generation, such as dry ice or liquid nitrogen, taken out of the cool container is inserted into the bag-like film together with the tennis ball, the insertion opening is joined by heat fusion and sealed.

Conventionally, in the packaging of a rigid tennis ball, 2
A plurality of balls such as individual, three, four, six, and twelve balls are wrapped in a single packaging container. However, when any of the above-mentioned can containers and bag-like films is used, With a simple operation, a plurality of hard tennis balls can be packaged at a low cost with the pressure inside the packaging material increased.

The amount of the liquid or solid vaporizable substance that evaporates at normal temperature and pressure is determined according to the predetermined pressure inside the packaging material to be set. For example, when the article to be wrapped is a rigid tennis ball, as described above, the internal pressure of the wrapping material needs to be substantially equal to or higher than the internal pressure of the ball in order to prevent a decrease in the internal pressure of the ball. . In the case of a hard tennis ball, in order to make the internal pressure of the ball equal to the pressure inside the packaging material, the amount of the liquid or solid vaporizable substance that vaporizes at normal temperature and normal pressure is determined by the amount of the vaporizable substance that when vaporized inside the interior of the packaging material is required to be an amount that causes an increase in pressure (P _U) defined by the following formula (1).

[0016]

## EQU1 ## P _U = P ₁ −P ₀ (1)

In the formula, P ₁ is the internal pressure (kPa) of the hard tennis ball to be packed, and P ₀ is the atmospheric pressure (kPa). However, it actually suppress a decrease in the internal pressure of the ball even if the pressure inside the actual packaging than P _U is the target value of about 20kPa small. Therefore, the insertion amount of the volatile substances to be inserted into the packaging material has good to the amount allowed to increase the pressure above the (P _U -20) kPa, preferably (P _U -
10) The pressure is preferably set to an amount that increases the pressure of kPa or more, more preferably P _U kPa or more. In other words, the pressure inside the packaging material after the vaporizable substance is vaporized is (P _U −
20) kPa or more, preferably (P _U -10) kPa or more, more preferably preferably set to more than P _U kPa. Also, if the pressure rise is too large, the ball may be distorted, the packaging material may burst, or a gap may occur at the joint for sealing, although it depends on the material and packaging form of the packaging material, The pressure rise should not be greater than (P _U +40) kPa. Therefore, the amount of the vaporizable substance to be inserted into the packaging material should be an amount that increases the pressure of (P _U +40) kPa or less. Well, preferably (P _U
+20) kPa or less, more preferably (P _U +10) k
It is preferable that the pressure be Pa or less. In other words, the pressure inside the packaging material after the vaporizable substance has been vaporized is (P _U +40) kPa or less, preferably (P _U +2)
0 kPa, and more preferably (P _U +10) kPa. Therefore, the insertion amount of the volatile substances to be inserted into the packaging _{material, (P U -20) ~ (} P U +40) good, but the amount of pressure increase occurs in the range of kPa, more preferably (P _U -10) It is preferable that the pressure increase is in the range of (P _U +20) kPa, more preferably in the range of P _U to (P _U +10) kPa.

Specifically, the internal pressure of a hard tennis ball is generally about 182 kPa, and when the internal pressure of a hard tennis ball to be wrapped is about 182 kPa,
Since the atmospheric pressure is 101 kPa, 61 (182-10)
The pressure is preferably an amount that causes a pressure rise in the range of 1-20) to 121 (182-101 + 40) kPa, and is preferably 71 (182-101-10) to 101 (182).
−101 + 20) kPa, more preferably 81 (182)
The pressure is preferably set to an amount that causes a pressure rise in the range of −101) to 91 (182−101 + 10) kPa.

When dry ice is used as a solid vaporizable substance which vaporizes at normal temperature and normal pressure, the effective volume inside the packaging material (the volume inside the packaging material minus the total volume of all the inserted hard tennis balls) ), When 0.018 g of dry ice per liter of effective volume is put in the packaging material,
After the dry ice evaporates, the pressure inside the packaging material should be about 1
kPa rises. Therefore, when the internal pressure of the hard tennis ball to be wrapped is about 182 kPa, the rising pressure of the wrapping material after the dry ice is vaporized is set to be in the range of 61 to 121 kPa. .018 × 61 to 0.018 × 121 g, that is,
The ball is packed without reducing the internal pressure of a general hard tennis ball using dry ice in the range of 1.1 to 2.2 g, and without causing problems such as deformation of the ball and bursting of the packaging material. can do. Preferably, 1.3 (0.018 × 71) to 1.8 (0.018)
× 101) g, more preferably 1.5 (0.01
Dry ice in the range of 8 × 81) to 1.6 (0.018 × 91) g is preferably used.

The above values are taken into consideration in consideration of measurement errors when weighing the vaporizable substance, the vaporized amount at that time, and the vaporized time from when the vaporizable substance is taken out of the cooler and inserted into the packaging material. No, we believe the figures will fluctuate slightly.

[0021]

Embodiments of the present invention will be described below. (First Embodiment) As shown in FIG. 1, two hard tennis balls 1 having an internal pressure of 186 kPa and dry ice 2 taken out of a cool container (not shown) are put into a steel can 10 having an open upper portion. The opening was covered with the lid member 3 and the steel can was sealed by caulking. Ten sealed cans of such a tennis ball were prepared. These were left under normal temperature and normal pressure.

Here, the inner volume of the steel can is 0.570.
Liters, the total volume of two tennis balls is 0.287 liters, the effective volume in a steel can is 0.283 liters,
The dry ice amount was 0.46 g.

When the pressure inside the cans of each of the 10 cans was measured after one month, the internal pressure of the cans was 186 to 192 kPa, and the internal pressure of the inserted tennis balls was maintained at 182 kPa. Was.

(Second Embodiment) An aluminum film 11 is disposed at the center shown in FIG. 2, a polyethylene terephthalate film 12 is laminated on both upper and lower surfaces thereof, and a low density polyethylene film 13 is laminated on one of the polyethylene terephthalate films 12. 2 of the laminated film 20
Prepare two sheets and use both films as low-density polyethylene film 1.
The three pieces were overlapped so as to overlap each other, and the three edges were heat-sealed to form a bag-shaped packaging material 21.

Next, as shown in FIG. 3, three hard tennis balls 1 having an internal pressure of 182 kPa and dry ice 2 taken out of a cool container (not shown) are put into the bag-like packaging material 21. The opening was heat-sealed to seal the bag-shaped packaging material 21. Ten such tennis ball sealed bags were prepared. These were left under normal temperature and normal pressure.

Here, the inner volume of the bag-like packaging material 21 is 1.
105 liters, total volume of three tennis balls is 0.43
1 liter, the effective volume of the bag-shaped packaging material 21 is 0.674.
The liter and the amount of dry ice were 1.10 g.

FIG. 4 shows the above-mentioned tennis ball sealed bag one month after the sealing. 1 month after this one month has passed
When the pressure inside the bag was measured with respect to 0 tennis ball sealed bags, the internal pressure of all 10 bags was 185 to 190 kPa.
The internal pressure of the inserted tennis ball was maintained at 182 kPa.

On the other hand, as shown in FIG. 5, a polyethylene terephthalate film 12
Are laminated, and two laminated films 22 are further prepared by laminating the low-density polyethylene film 13 on the polyethylene terephthalate film 12 on both sides, and the two films are laminated, and the three edges are heat-sealed and the same as above. A bag-like wrapping material was prepared, and the same test was performed using the wrapping material. The same good result was obtained.

In the above embodiment, one or more articles are wrapped in one wrapping material. However, a plurality of packages obtained by wrapping one or more articles in one wrapping material are described. It goes without saying that the packaging method of the present invention can also be applied to a packaging form in which the individual is further packaged with a packaging material.

[0030]

As is clear from the above description, according to the method for packaging articles of the present invention, there is no need to use special equipment or perform special processing on the packaging material as in the prior art, and the packaging operation can be performed. Since it is only necessary to pack the vaporizable substance with the packaging material together with the packaging material, and since the vaporizing substance such as dry ice and liquid nitrogen is relatively inexpensive, the product can be easily and inexpensively put into the high pressure state inside the packaging material at low cost. Can be packaged. Further, a vaporizable substance such as dry ice or liquid nitrogen does not generate moisture due to vaporization, and thus does not adversely affect the physical properties of the article.

[Brief description of the drawings]

FIG. 1 is a schematic view of an operation of packaging a hard tennis ball using the steel can of the first embodiment.

FIG. 2 is a sectional view of a laminated film (packaging material) used in a second embodiment.

FIG. 3 is a schematic view of an operation of packaging a hard tennis ball using the bag made of the laminated film of FIG. 2;

4 shows the state of the package obtained by the operation of FIG. 3 after one month has passed, (A) is a side view looking at a short part, and (B) is a side view looking at a long part. is there.

FIG. 5 is a cross-sectional view of another example of a laminated film (packaging material) used in the second embodiment.

[Description of Signs] 1 Hard tennis ball 2 Dry ice 3 Cover material 10 Steel can 21, 22 Packaging material

Claims (3)

[Claims] 1. A liquid or solid vaporizable substance, which vaporizes at room temperature and normal pressure together with an article, is inserted into the inside of the packaging material to seal the packaging material, and then the liquid or solid vaporizable substance is vaporized. A method for packaging an article, wherein the inside of the packaging material is pressurized. 2. The method for packaging an article according to claim 1, wherein the article is a hard tennis ball. 3. The method for packaging an article according to claim 1, wherein the vaporizable substance is dry ice.