JPH0330057B2 - - Google Patents

Description

[Detailed description of the invention]

[Industrial Application Field] The present invention relates to a container particularly suitable for making puffed foods such as steamed bread and cakes using a microwave oven. [Prior Art] Steamers, ovens, oven ranges, and the like have been used to make steamed bread, cakes, etc., but they have the drawback of requiring a long time to make cakes, etc. using these devices. On the other hand, in recent years, microwave ovens have become widely used for home use instead of ovens and oven ranges due to their convenience and high safety, and have become an indispensable household cooking appliance. In other words, microwave ovens use a heating method different from ovens, etc. In other words, microwave ovens use microwave heating methods, so the containers do not need to be fireproof when cooking, and disposable containers such as paper or plastic can be used. It has the advantage that it can be used. However, if you use a paper container to make steamed bread or cake in the microwave, the steam generated during cooking may reduce the strength of the paper, or the steamed bread or cake may stick to the inside of the container after cooking. There is a problem that is said to be difficult to remove. Furthermore, even when a plastic container is used, depending on the type of plastic, there is a problem in that steamed bread or the like may adhere to the inner surface and be difficult to remove. [Problems to be Solved by the Invention] Therefore, the present invention provides a microwave oven that does not allow steamed bread, cakes, etc. to be attached to the inner surface of the container when making steamed bread, cakes, etc. using a microwave oven. The purpose is to provide containers for cooking.
Another object of the present invention is to provide an inexpensive disposable microwave cooking container. [Means for solving the problem] The above problem is solved by using plastic laminate paper, in which the inner surface of the container has a layer of heat-resistant synthetic resin having a specific critical surface tension, and the outer surface of the container is made of paper. We have found that this problem can be solved by constructing a container using In other words, it is a container in which the side wall and lid are integrally formed, only the inner surface of the container is coated with a heat-resistant synthetic resin with a critical surface tension of 33 dyn/cm or less, and the outer surface is made of paper. To provide a microwave cooking container for cooking puffed food in a microwave oven, which is characterized by: Examples of the heat-resistant synthetic resin for the inner surface of the container used in the present invention include plastics such as polyethylene and polymethylpentene. Here, heat resistance refers to something that does not melt when heated in a normal microwave oven, and preferably has a melting point of 100° C. or higher. In the present invention, the critical surface tension of the above-mentioned plastics is 33 dyn/cm, taking into account additives such as antistatic agents, presence or absence of surface treatment, etc.
Hereinafter, it is preferable to use paper coated with a plastic film of 30 dyn/cm or less. In other words, if the critical surface tension exceeds 33 dyn/cm, bread, cake, etc. will stick to the inner surface of the container and cannot be removed. Incidentally, the term "coating" as used herein includes bonding a plastic film to paper by any means such as lamination.
Further, the thickness of the plastic film to be coated can be set arbitrarily, but in consideration of use and disposableness, it is 12 to 100μ, preferably 20 to 50μ.
It is better to In the present invention, various types of paper can be used to form the outer surface of the container, ie, the paper on which the plastic sheet is coated, but paper commonly used for packaging boxes is preferred. Specific examples include cardboard, paperboard, and virgin pulp paper. or,
These preferably have a basis weight of 210 to 370 g/m ² . The present invention is characterized in that a container is formed by using the above-mentioned two-layered laminated paper with the plastic layer facing the inner surface. The purpose of the invention is not achieved. In addition, when a plastic sheet is further laminated on the paper surface of the above-mentioned two-layer laminated paper, when cooking steamed bread etc. in a microwave oven, water vapor etc. are difficult to escape from the paper surface.
This is not preferable because a problem arises in which the laminate layers eventually peel off. Therefore, it is desirable that the paper surface is not coated with a material with poor water permeability such as wax. In the present invention, the container can take any form as long as it has the above-mentioned configuration.
For example, it has a cylindrical shape, a cubic shape, a rectangular parallelepiped shape, a polygonal column shape, etc. In this case, it is particularly preferable to use a container with a lid, which is formed by expanding a lid that has an opening at the top and is formed integrally with the side of the container. [Effects of the Invention] According to the present invention, when steamed bread, cakes, etc. are made in a microwave oven, the steamed bread, etc. do not adhere to the inner surface of the container, and steamed bread, etc. in a beautiful shape can be easily obtained. Furthermore, the container of the present invention has the advantage that it can be manufactured at a low cost, so it can be conveniently used as a disposable container, and it can also be used as tableware as it can be served directly after cooking. Because it has good properties, it can also be used as a container for making porridge, seasoned rice, etc. in the microwave. Next, the present invention will be explained with reference to Examples. Example A cubic container with a lid was made using a laminated paper whose inner surface was made of plastic film as described below and whose outer surface was made of paperboard. To this was added 122 g of a premix having the composition shown below, and 100 ml of water was added, stirred and mixed thoroughly, and then heated in a microwave oven (500 W) for 4 minutes to make steamed bread. Table 1 shows the adhesion of steamed bread to the inner surface of each container.
Shown below. Furthermore, the critical surface tension of the inner film is
It was measured according to the method of JISK6768,
When measuring 30 dyn/cm or less, a mixed solution of ethylene glycol monoethyl ether and tert-butyl alcohol was used as a standard solution.・Premix flour 52% Sugar 25% Sorbit 8% Milk powder 4% Egg white powder 2.2% Oil 4% Emulsifier 1% Baking powder 3.5% Salt 0.3% Total 100% The above percentages are by weight.

[Table] From the results in Table-1, the critical surface tension is 33dyn/cm
It can be seen that adhesion of the contents can be effectively prevented by using the following films.

Claims (1)

[Scope of Claims] 1. A container in which the container side wall and the lid are integrally formed, wherein only the inner surface of the container is coated with a heat-resistant synthetic resin having a critical surface tension of 33 dyn/cm or less, and the outer surface is made of paper. characterized by being formed,
A microwave cooking container for cooking puffed foods in the microwave. 2. The container according to claim 1, wherein the heat-resistant synthetic resin is polyethylene or polymethylpentene. 3 The thickness of the inner synthetic resin film is 12 to 100μ
A container according to claim 1 within the scope of claim 1.