JPH03148473A - Food package suitable for heat-cooking by microwave oven - Google Patents

Abstract

PURPOSE:To make a package of food excellent in sealing and free from the possibility of tearing at the sealing the stage of distribution and adapt it to cooking by microwave oven by packaging the food inside inner layer-forming laminates one laminate of which is formed of 1,4-butanediol or propylene glycol and an acid component containing terephthalic acid and the other laminate of which is formed of polyethylene terephthalate, by placing these inner layers opposite to each other in packaging the food therein, and by closing package at a specific heat-seal strength around it. CONSTITUTION:The food package contains food inside inner layer-forming laminates in such a manner as to hold food between the inner layers placed opposite to each other, one of said laminates being formed of 1, 4-butanediol or propylene glycol and an acid component composed of two or more acids which include terephthalic acid and the other laminate B being formed of polyethylene terephthalate and the package being heat-sealed around at a heat-seal strength of 0.5-1.3 kg/15 cm width. A package thus formed has a good tightness and, when heated by microwave oven, the package allows steam produced by heating to break the seal and escape. The tightness is inadequate if the seal strength is below 0.5 kg/15 mm width, whereas heating fails to break the seal if the seal strength is over 1.3 kg/15 mm width.

Description

[Detailed Description of the Invention] <Industrial Icheon Field> The present invention relates to a food package suitable for microwave cooking that does not transfer odor to food and does not cause rupture or the like when heated in a microwave oven. .

<Prior art> When a food package with food sealed inside a bag or container is cooked in a microwave oven, as the cooking progresses,
Water vapor was generated inside the package, increasing the internal pressure and causing the food package to expand and burst.

Therefore, if you open the food package and heat it by transferring it to another container, or heat it with the bag or container open and let the water vapor generated by heating escape, the food package may expand and burst. was prevented.

In this way, when heating, it is necessary to take the trouble to open the bag or peel off the lid of the container, and furthermore, when opening or peeling off the lid, the contents may spill and make a mess.

<Problem to be solved by the invention> As described above, with the spread of microwave ovens, the number of food products that are heated and cooked in microwave ovens is increasing.
It has excellent sealing properties for preservation in a distribution state, and when it is heated in a microwave oven, tools or the like must be used to open it, making the opening process cumbersome.

SUMMARY OF THE INVENTION Therefore, an object of the present invention is to provide a food package that has excellent sealing properties in a distribution state and can be heated in a microwave oven as it is without having to take the trouble of opening the package.

<Means for Solving the Problems> The present invention provides a laminated material A in which the inner layer is made of an acid component made of two or more acids including terephthalic acid and 1,4-butanediol or propylene glycol, and the inner layer is made of polyethylene terephthalate. A food product is stored in a laminated material B consisting of a laminate B with the inner sides facing each other, and the periphery is heat-sealed, and the heat-sealing strength is 0.5 to 1.3 kg/15 mm width. This is a food package suitable for microwave cooking.

Further, the food packaging body is bag-shaped, or is suitable for microwave oven cooking in which the laminate material 8 is used as a lid material and the laminate material B is used as a molded container.

4 Effects> Since the inner layer of the laminated material constituting the food package is made of polyester resin that does not contain plasticity, the plasticizer in the resin does not transfer to the food during food storage, so there is no change in the taste or smell of the food.

Moreover, since they have the same structure, they have heat resistance, and there is no fear that the bags and containers constituting the food packaging body will be deformed even when heated in a microwave oven.

Furthermore, since the inner layer of the laminate is made of two acid components including terephthalic acid and polyester and polyethylene terephthalate consisting of 1.4-butanediol or propylene glycol, the heat seal strength is 0.5 to 1.3.
kg/15 mm width, and has sufficient sealing performance, and when heated in a microwave oven, the seal part peels off due to the water vapor generated by heating, allowing the water vapor generated inside to escape.

If this seal strength is less than 0.5 kg/15 mm width, the sealing performance is insufficient and it cannot function as a container.If it exceeds 1.3 kg/15 mm11, it will not peel off due to heating cannot be achieved.

<Example> A polyester (sample 1) consisting of 60 mol% terephthalic acid and 40 mol% isophthalic acid as the acid component, 1゜4-butanediol as the diol component, 54 mol% terephthalic acid as the acid component, and 54 mol% adipic acid. is 46 mol%, polyester (sample 2) consisting of 1,4-butanediol as the diol component, and 75% isophthalic acid as the acid component.
Polyester consisting of 25 mol% of terephthalic acid and propylene glycol as the diol component (Sample 3)
) was used as the inner layer, and laminate material A, which was laminated with two-wheel stretched polyethylene terephthalate film, was used as the lid material.

On the other hand, using a thermoformed container made of laminated material B whose inner layer is polyethylene terephthalate and whose outer layer is polypropylene,
This container was filled with 200 ml of water, the lid material was placed on top of the container, and the surrounding area was sealed at 200° C. for 1 second to obtain a food package.

Next, each food package was heated in a 500 W microwave oven for 3 minutes, and the JIIM and seal strength of the sealed portion were measured.

The results are shown in Table 1.

Table 1 1-1 Sheet J1 Sukan I Sheet tmυ state before heating 11
wt1 1.3 1m-ant 11
Sample 21 1.2 1 Same as above 1
1 sample 31 0.5 l Same as above
1 or more, the seal strength before heating is 0.5 to 1
- By using laminated material A with a width of 3 kg/15 mm, suitable sealing strength can be obtained as a lid material for polyester containers that do not contain plasticizers, and when heated in a microwave oven, the seal part will peel off and the internal The container no longer deforms or bursts due to the generated water vapor.

<Effects of the Invention> Since the present invention has the above configuration, there is no risk of plasticizers transferring to food, and the food packaging is excellent in terms of safety and hygiene.Moreover, by using polyester with a specific component, The sealing strength before heating with polyethylene terephthalate is 0.5 to 1°3 kg/15 mm, and the seal part will not peel off due to the pressure of steam generated by heating, and the container will not be deformed or burst.

As a result, in the past, the food package of the present invention had to be opened before being heated in a microwave oven, but the food package of the present invention
It can now be heated directly in the microwave, making it easy to use.

Patent applicant Toppan Printing Co., Ltd. Representative: Kazuo Suzuki

Claims (3)

[Claims] (1) The inner layers of laminate material A, whose inner layer is made of an acid component made of two or more acids including terephthalic acid, and 1,4-butanediol or propylene glycol, and laminate material B, whose inner layer is made of polyethylene terephthalate, face each other. 1. A food package suitable for microwave cooking, characterized in that the heat sealing strength obtained by storing a food product in the same state and heat-sealing the periphery thereof is 0.5 to 1.3 kg/15 cm width. (2) The food package suitable for microwave cooking according to claim (1), wherein the package is bag-shaped. (3) The food package suitable for microwave cooking according to claim (1), wherein the laminated material A is a lid and the laminated material B is a molded container.