JPS6312442A - Sterilized package of aqueous content containing carbonic acid gas and manufacture thereof - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of Industrial Application The present invention relates to a sterilized package for aqueous contents containing carbon dioxide gas and a method for producing the same. This invention relates to a sterile package for gas-containing aqueous contents and a method for producing the same.

PRIOR ART AND TECHNICAL PROBLEMS OF THE INVENTION Conventionally, a glass container has been used as a trough 4 for a package of carbon dioxide-containing aqueous contents requiring fjRfMJA embedding. The reason for this is that when a package containing carbon dioxide gas-containing aqueous contents is heat sterilized, carbon dioxide gas dissolved in the aqueous contents is released from the aqueous contents as the temperature rises due to heating. Accumulation in the head space of the package,
This is because if a plastic container is used as a container for the package, the increased internal pressure of the package will deform the plastic container. Deformation of a package using such a plastic container does not always occur in the same part of the package, and may be caused by force caused by the uneven shape of the package product, especially if the bottom of the package is deformed. This brings about a serious drawback in that the package does not "sit" well. In particular, for hospitals, 11 [f
In the case of a package containing water, the electrical storage (sodium bicarbonate) in the contents decomposes when heated and generates carbon dioxide gas, so a plastic container is used as the infusion container for drip type 1 water. In this case, the deformation caused by heat sterilization is significant.

However, glass containers have drawbacks such as being easily broken and being heavy. Furthermore, especially when a glass container is used as an infusion container for intravenous sodium bicarbonate solution, the glass is corroded by the 1st grade and flakes are formed in the 2nd grade water, and these flakes may clog the intravenous solution or reduce the effectiveness of the heavy q water. There is a drawback that it decreases. Both glass containers and plastic containers have their drawbacks as containers for intravenous infusions, so packages of sodium bicarbonate solution for intravenous drips (with a content of about 500 IIL) are still not commercially available. Not manufactured.

In addition, recently, recreational foods and beverages containing small amounts of carbon dioxide gas, such as fruit juices, sports drinks, coffee, and jelly, have been on sale. Beverages that contain a large amount of carbon dioxide gas, such as colas, do not need to be heat sterilized because they have sterilizing properties, but recreational foods that contain a small amount of carbon dioxide gas need to be heat sterilized. . Heat sterilization of food and beverage packaging containing small amounts of carbon dioxide using plastic containers causes the drawbacks mentioned above. At present, plastic containers are not being used as containers for sterilized food and drink packaging.

Purpose of the Invention An object of the present invention is to maintain the shape of the package for aqueous contents containing carbon dioxide gas without deformation even after heat sterilization, and to maintain the shape before heat sterilization, and to provide excellent carbon dioxide. It is an object of the present invention to provide a sterile package for aqueous contents containing carbon dioxide gas, which has gas barrier properties and excellent appearance characteristics, impact resistance, internal pressure resistance, transparency, etc., and a method for producing the same.

Structure of the Invention According to the present invention, a sterilized package of carbon dioxide gas-containing aqueous contents is provided, in which the carbon dioxide gas-containing aqueous contents are sealed in a plastic container sealed at one mouth.
It is formed from a thermoplastic resin having hot water resistance of 0°C or higher, and has a mouth sealing part having a diameter smaller than the body diameter, a bottom part having a wall thickness larger than the body wall thickness, and a normal pressure The body has a thick body that can be deformed with a small force, and the body has a vertical cross-section in the axial direction of the central part of the body according to the following formula (where F is the flatness and SO is the circumcircle of the body wall cross-section). , where Sl represents the cross-sectional area surrounded by the body wall), is in the range of 0.15 to 0.9. The body is provided.

Further, according to the present invention, the sealing opening is made of a thermoplastic resin having hot water resistance of 100° C. or higher and has a diameter smaller than the diameter of the body, and the bottom has a wall thickness larger than the thickness of the body. , and a thick-walled body that can be deformed with a small force under normal pressure, and the body has a vertical cross section in the axial direction of the central part of the body according to the following formula (where F is the flatness and so is the body wall cross section. 8. represents the cross-sectional area surrounded by the body wall) is in the range of 0.15 to 0.9. or a carbonated aqueous content such that a headspace is formed, or in conjunction with filling with an aqueous content;
After filling with carbon dioxide in an amount that does not apply internal pressure, the mouth of the container is sealed to form a package, and the package is placed in a sterile atmosphere so that the contact area between the aqueous contents and the head space is large. The pressure of the atmosphere is maintained at a pressure commensurate with the internal pressure of the container, and heat sterilization is performed, and the sterilized package is rapidly cooled to remove carbon dioxide gas in the headspace from the aqueous contents. A method of making a sterile package of an aqueous content containing carbon dioxide is provided.

Effects of the Invention The container used in the package of the present invention has an oblateness of 0.1 as defined above in the axial vertical cross section of the center of the body.
Since the container has a specific shape in the range of 0.5 to 0.9, when a package of aqueous contents containing carbon dioxide gas is sterilized using this container, the internal pressure of the package is increased by heating. In order to prevent deformation due to "bulging" of the package due to sterilization, deformation is suppressed by heat sterilization while maintaining the pressure of the sterilized atmosphere at a pressure commensurate with the internal pressure, and when cooling after sterilization, Deformation of the packaging due to residual internal pressure in the headspace due to delayed absorption of carbon dioxide gas into the aqueous contents in the headspace can be avoided by removing the electrical components from the aqueous contents during sterilization. By placing the package in such a way that the contact area with the space is large, the absorption rate of carbon dioxide gas is increased, and by rapid cooling, the absorption t of carbon dioxide gas is increased, thereby suppressing the deformation of the package and automatically Ru. In addition, deformation of the package during sterilization tends to occur in weak parts of the container of the package, but the container of the package has a structure in which the wall thickness of the bottom part is larger than the wall thickness of the body part. Therefore, even if the body portion is slightly deformed, the bottom portion will not be deformed at all, and the package 9 can be easily obtained with excellent “sitting” stability.

Preferred Embodiments of the Invention The plastic container used in the present invention is made of a thermoplastic resin having hot water resistance of 100°C or higher, and has a mouth sealing portion having a diameter smaller than the body diameter, and a mouth sealing part having a diameter smaller than the body diameter. The body has a bottom part with a large wall thickness, and a body part with a thick wall that can be deformed with a small force under normal pressure. degree, So is the area of the circumcircle of the section of the body wall, and S is the cross-sectional area surrounded by the body wall) is in the range of 0.15 to 0.9, preferably 0. 30 to 0.85.

The temperature of the thermoplastic resin is 100°C or higher, preferably 10°C.
It has hot water resistance of 5°C or higher and low carbon dioxide gas permeability, preferably carbon dioxide gas permeability of 20°C at 20°C.
Qcc/m" @ day ・atyI&(thickness 111
m) It is possible to use all monolayer or multilayer thermoplastics which are:

Such thermoplastic resins include high density polyethylene, crystalline polynolopyrene, crystalline nolopyrene copolymer,
Polycar? A monolayer of polyester, aromatic polyester, etc., or an inner and outer surface layer made of these thermoplastic resins, and a thermoplastic resin 1 with excellent carbon dioxide gas barrier properties, for example,
A multilayer structure formed from an intermediate layer made of polyamide, ethylene-vinyl alcohol copolymer, polyvinyl chloride, etc., and an adhesive layer provided between the inner and outer surface layers and the intermediate layer, if necessary. Body thermoplastics can be used. Aromatic polyester is an aromatic polyester obtained from an alkylene glycol having 2 to 4 carbon atoms and aromatic zocarinic acid, containing 0 mol or more of ethylene terephthalate structural unit fnia.

These thermoplastic resins may contain nucleating agents, inorganic fillers, lubricants, slip agents, anti-blocking agents, stabilizers, antistatic agents, anti-adhesion agents, pigments, etc. that are conventionally blended into polyester. Appropriate amounts of various additives may be blended.

Particularly preferred thermoplastic resins having carbon dioxide gas barrier properties include polyamide, ethylene-vinyl alcohol copolymer, and vinylidene/vinylidene chloride. The polyamide includes aliphatic, aromatic, araliphatic cyamine and aliphatic, aromatic zocarmenic acid, or aliphatic, aromatic, araliphatic aminocarmenic acid or its lactam,
Alternatively, polyamides or copolyamides prepared from mixtures thereof may be used. Such polyamides are known per se, and from the viewpoint of gas barrier properties against acid bulk, carbon dioxide, etc., the number of amide groups per 100 carbon atoms in the polyamide is 3 to 30, particularly 4 to 25. It is preferred to use homopolyamides, copolyamides or blends thereof within the range.

Examples of suitable homopolyamides are nylon 6, nylon 9
, nylon 11. These include nylon 12, nylon 6.6, nylon 6.12, and 7. Examples of suitable copolyamides include Caglolactam/Laurinlactam copolymer, Power! rolactam/hexamethylene diammonium anovate copolymer, and others.

In addition, although it is slightly inferior in moldability compared to the above-mentioned aliphatic polyamide, it is disclosed in, for example, Japanese Patent Publication No. 50-1156, Time Publication No. 1150-5751, 1% Publication No. 50-5753, and Japanese Patent Publication No. 50-10196. , Japanese Patent Publication No. 50-2
metaxylylene diamine, or metaxylylene diamine and a mixed chyrylylene diamine containing 30 or less -f-xylylene diamine in the diamine, as described in Japanese Patent No. 9697, etc., and a carbon number of 6 to 1.
It is also possible to use aromatic polyamides having in the molecule A at least 70 mol'/62 of constitutional units formed from 0 α,ω-aliphatic dicarboxylic acids.

Further, an aromatic zocal compound containing meta-xylylene diamine, or meta-xylylene diamine and a mixed xylylene cyanine containing 30 or less or laxylylene diamine in a diamine and isophthalic acid at 30 mol or more, preferably 40 mol or more? It is also possible to use an aromatic polyamide containing at least 70 moles of a structural unit formed from a y-acid in its molecular chain.

Furthermore, metaphenylenediamine and/or
Aromatic polyamides containing 30 moles or more, preferably 40 moles or more of 4-phenylenezoamine and isophthalic acid can also be used.

The molecular weight of these /+7 amides can be used without any particular restriction as long as it is generally within a range that allows film formation.

Mataethylene-vinyl alcohol co-tf form.

In order to improve gas barrier properties, a copolymer with an ethylene component of 50 mole or less is preferable.
The vinyl alcohol copolymer is obtained by saponifying a copolymer with a vinyl ester such as ethylene vinyl acetate, and has an ethylene content of 15 to 50 moles, particularly 25 to 45 moles, and a degree of saponification. is preferably 96 or more.

It is also possible to use a blend of these polyamides and an ethylene-vinyl alcohol copolymer.

In addition, since aromatic polyester and thermoplastic resin having carbon dioxide gas barrier properties generally have poor adhesion, when forming the multilayer structure, especially when stretching it, Easy to cause delamination. Therefore, it is preferable to provide a suitable adhesive layer between the inner and outer surface layers and the intermediate layer. Examples of the adhesive include polyester adhesives, copolyamide adhesives, and others.

From the viewpoint of the strength and gas barrier properties of the container, it is preferable that the wall of the container extends at least in the l-axis direction, particularly in two mutually perpendicular axes directions.

The stretching ratio is 1.1 to 10 times, preferably 1.2
It is 8 times to 8 times, more preferably 1.5 to 7 times.

Such a stretched multilayer container can be manufactured by a method known per se, such as a blow molding method or a sheet molding method.

The flatness of the plastic container in the present invention is the same as defined above, and will be explained in more detail in FIGS. 1 and 2, including the shape of the container.

FIG. 1 is an elevational view of an example of a container used in the present invention, and FIG. 2 is a sectional view taken along the line A-A' in FIG. 1st
In the figure, the diameter of the sealing opening 2 of answer 51 is smaller than the diameter of the body 3, and the thickness of the bottom 4 is larger than that of the body 3. Figure 2 is.

It is an axial vertical cross-sectional view of the central part of the body 3, and the flatness of the container l is defined as 8, the area of the circumcircle 5 of the body wall cross section, and SR, the cross-sectional area surrounded by the wall of the body 3. To manufacture the package of the present invention, first, the carbon dioxide-containing aqueous content or the carbon dioxide-generating aqueous content is placed in the plastic container so that a head space is formed. After filling with charcoal #1 gas, the mouth of the container is sealed. is preferably 3 to 30% of the aqueous content volume.

The aqueous content containing carbon dioxide gas or the aqueous content generating carbon dioxide gas must be heat sterilized after being placed in a container and sealed. and liquid foods and drinks containing carbon dioxide gas, such as fruit juice, sports drinks, coffee, and jelly.

Next, the package prepared as described above is placed in a sterile atmosphere in such a way that the contact area between the aqueous contents and the head space is even, and the pressure f of the atmosphere is adjusted to match the internal pressure of the container. Heat sterilization is performed while maintaining the pressure, and the package after sterilization is rapidly cooled to dissolve carbon dioxide in the head space into the aqueous content, thereby producing a sterilized package containing carbon dioxide-containing aqueous content. - Manufacture.

The temperature for heat sterilization is usually 100 to 120°C. The pressure of the sterilization atmosphere can be calculated from the amount of carbon dioxide gas inside the package, the head space volume, the sterilization temperature, etc. Also, the amount of deformation due to "bulging" of the package during sterilization can be calculated mechanically or electrically. It is also possible to manually or automatically adjust the pressure of the sterile atmosphere so that the amount of deformation is minimized.

The method for producing a sterilized package of the present invention involves heat sterilizing a package containing a carbon dioxide-containing aqueous content in a plastic container, which could not be conventionally heat sterilized, by a simple means.
Moreover, the package after heat sterilization is stable as it maintains its original container shape without deformation, and is a sterile package containing carbon dioxide-containing aqueous contents in a plastic container that will not be damaged during handling. body can be manufactured.

Example 1 Both the inner and outer surface layers are made of polypropylene (melt index M, 1.=1.5, ethylene content [3% by weight), the intermediate layer is an ethylene-vinyl alcohol copolymer, and the adhesive layer is made of modified polypropylene. The long axis of the body is 83+w+, which is molded by stretch blow molding from a laminate (body average wall thickness 0.6+m, bottom average wall thickness 0.9m).
The inner volume is 7101 tl, having the shape shown in Figs. 1 and 2, in which the short axis of the body is 55 mm and the flatness F is 0.76.
An aqueous solution 51 containing 7% by weight of sodium hydrogen carbonate and 0.3 weight tS of sodium thiosulfate was placed in a plastic container.
The container was filled with 0x/ and the mouth was sealed. The headspace volume was 200it/. This package was placed in a retort and placed on a retort shelf with the long side of the body facing down and lying on its side as shown in FIG. The temperature inside the retort is 1
The temperature was raised to 00°C and maintained at 100°C for about 85 minutes for sterilization. Check the internal pressure of the retort while observing the package.
Adjustment was made so that the body of the package was slightly concave. The maximum pressure was approximately 2.2 kg/m2 (darts). After the sterilization process was completed, the temperature inside the retort was lowered to 20° C. in 3 minutes. As the internal pressure of the package decreased as it cooled, the retort pressure was also decreased accordingly. After sterilization, there is almost no bulge in the body of the package, and the only deformation of the body is that the lower part becomes very slightly flattened when placed in the retort. There were no problems with stability. Furthermore, the body of the package left for one week after sterilization was slightly depressed.

Comparative Example 1 The package was heat sterilized in the same manner as in Example except that the package was placed upright on a retort shelf with its bottom facing down. After sterilization, the lower half of the package was noticeably swollen and deformed, and the bottom was slightly crushed. When the package was left for one week after sterilization, the bulge in the body area was slightly reduced, but some remained.

Comparative Example 2 The procedure of Example 1 was repeated, except that the package was placed on a retort shelf with its bottom facing down, and a jig was used to hold down the short side of the mettle (leaving the neck and shoulders open). Heat sterilization was performed in the same manner as in the case of Suzu. After the ridges were removed, the body of the package was noticeably swollen and deformed, and the bottom was slightly crushed. When the package was left for a week after sterilization, the bulge on the body had decreased slightly, but "there was still a slight bulge remaining."

Example 2 Polyzolopyrene (M, 1.5 mm) with an ethylene content of 1.5 mm.
=1.5) Stretched from a single layer! A container having the same shape as in Example 1, molded by a low molding method (body average wall thickness 0.85+w, bottom average wall thickness 1.2 wm)
The same procedure as in Example 1 was carried out except that . The package after sterilization had the same condition as the package after sterilization in Example 1.

[Brief explanation of the drawing]

FIG. 1 is an elevational view of an example of a container used in the present invention, and FIG. 2 is a sectional view taken along the line A- in FIG. 1. In FIGS. 1 and 2, 1 is a container. 2 is a sealing mouth, 3 is a body, 4 is a bottom, and 5 is a circumcircle of a cross section of the body wall. Figure 1, Figure 2, C).

Claims (4)

[Claims] (1) In a sterile package for carbon dioxide-containing aqueous contents, in which the carbon dioxide-containing aqueous contents are sealed in a plastic container that is sealed at the mouth, the container is made of thermoplastic resin having hot water resistance of 100°C or higher. a mouth sealing portion having a diameter smaller than the diameter of the body, a bottom portion having a wall thickness greater than the body wall thickness, and a body portion having a wall thickness that can be deformed with a small force at normal pressure, The body is defined by the following formula F = S_1/S_0 (where F is the flatness, S_0 is the area of the circumcircle of the body wall cross section, and S_1 is the area surrounded by the body wall). A sterilized package for an aqueous content containing carbon dioxide gas, characterized in that the flatness defined by the cross-sectional area (representing the cross-sectional area) is in the range of 0.15 to 0.9. (2) The thermoplastic resin has a capacity of 200cc/at 20°C.
m^2・day. The package according to claim 1, wherein the package is made of a thermoplastic resin having a carbon dioxide permeability of atm (thickness: 1 mm) or less. (3) A sealing opening made of thermoplastic resin that has hot water resistance of 100°C or more and having a diameter smaller than the body diameter, a bottom part having a wall thickness greater than the body thickness, and a The body has a thick body that can be deformed with a small force, and the body has a vertical cross-section in the axial direction of the central part of the body using the following formula F=S_1/S_0 (where F is the flatness and S_0 is the body wall). The area of the circumscribed circle of the cross section (S_1 represents the cross-sectional area surrounded by the body wall) is in a plastic container whose flatness is in the range of 0.15 to 0.9. After filling the container with an aqueous substance or a carbon dioxide-generating aqueous content to form a head space, or filling the aqueous content with an amount of carbon dioxide that does not create internal pressure, close the mouth of the container. The package is sealed to form a package, and the package is placed in a sterile atmosphere such that the contact area between the aqueous contents and the head space is large, and the pressure of the atmosphere is set to a pressure commensurate with the internal pressure of the container. Sterilized packaging for aqueous contents containing carbon dioxide gas, characterized in that the package body after sterilization is heated and sterilized to dissolve carbon dioxide gas in the head space into the aqueous contents. How the body is made. (4) The thermoplastic resin has a capacity of 200 cc/at 20°C.
The manufacturing method according to claim 3, wherein the thermoplastic resin has a carbon dioxide gas permeability of m^2 day atm (thickness 1 mm) or less.