JPH07153566A - Microwave oven heating sheet - Google Patents

Abstract

PURPOSE:To prevent overheat of a material to be heated by layering a water absorptive sheet and a conductive film having prescribed-sized holes on a non water permeable film. CONSTITUTION:A water absorptive sheet 2 and a conductive film 3 having holes 3a are layered on a non-water permeable film 1, and the size of the holes 3a is set in the size capable of shielding a microwave from a microwave oven. The film 1 is composed of a film or a sheet composed of heat resistant synthetic resin, and is also foamed, and heat insulating performance is applied. In a sheet 2, water absorptive polymers 2a are sandwiched by water absorptive papers 2b, and the papers 2b are also sandwiched by water permeable sheets 2c. Here, the two sheets 2c are formed in a bag shape by being fixed to each other on the periphery, and the water absorptive papers 2b are put in this bag with out being fixed. Then, a microwave radiated from the microwave oven is almost absorbed in the sheet 2, and water is heated, and a material 11 to be heated is heated by heat condition.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a microwave oven heating sheet used for heating an object to be heated in a microwave oven.

[0002]

2. Description of the Related Art A microwave heating sheet has a structure in which a water-absorbent polymer sheet and a water-permeable sheet are laminated on a non-water-permeable film, as disclosed in JP-A-4-103921. It has been known.

When using this to heat an object to be heated, the water-absorbent polymer sheet is made to absorb water and the object to be heated is wrapped with the water-permeable sheet inside and placed in a microwave oven. The water absorbed by the water-absorbent polymer sheet is heated in a microwave oven, and the object to be heated is indirectly heated by heat conduction. Further, steam passes through the water-permeable sheet, and steam heating is also performed in parallel. As a result, the object to be heated is uniformly heated from the surroundings and is heated with high thermal efficiency.

[0004]

However, in the above-mentioned conventional structure, most of the microwave from the microwave oven is absorbed by the water of the water-absorbent polymer sheet, but part of it is absorbed by the object to be heated and directly heated. Is done. Therefore, if the heating time of the microwave oven is set to a time much longer than the predetermined time by mistake, the object to be heated may be overheated.

[0005]

In order to solve the above-mentioned problems, the microwave heating sheet according to the present invention can shield at least the water absorbing sheet and the microwave from the microwave on the water-impermeable film. It is characterized in that a conductive film having a hole of a size is laminated.

[0006]

According to the above construction, when the water-absorbent polymer sheet is made to absorb water, the conductive film is placed inside to wrap the object to be heated, and the material is heated in a microwave oven, the water absorbed by the water-absorbent polymer sheet is heated. To be done. Then, the object to be heated is indirectly heated by heat conduction. Further, steam passes through the holes formed in the conductive film, and steam heating is also performed in parallel. As a result, the object to be heated is uniformly heated from the surroundings,
Moreover, it is heated with high thermal efficiency. In addition, even if accidentally heated for a long time, the microwave from the microwave oven is shielded by the conductive film. As a result, the object to be heated is not directly heated by the microwave oven, so that the object to be heated can be prevented from overheating.

[0007]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The following will describe one embodiment of the present invention with reference to FIGS.

Microwave oven heating sheet 10 of this embodiment
1 has a structure in which a water-absorbent sheet 2 and a conductive film 3 having holes 3a ... Are laminated on a water-impermeable film 1, as shown in FIG.

The water-impermeable film 1 includes polyethylene,
A film or sheet made of heat-resistant synthetic resin such as polyvinyl chloride or polypropylene is used. In addition, you may make it foam in order to provide heat insulation.

As shown in FIG. 2, the water-absorbent sheet 2 has a structure in which the water-absorbent polymer 2a ... Is sandwiched between water-absorbent papers 2b and 2b, and the water-absorbent papers 2b and 2b are sandwiched between water-permeable sheets 2c and 2c. There is. The two water-permeable sheets 2c, 2c are fixed to each other in the periphery to form a bag, and the water-absorbent papers 2b, 2b sandwiching the water-absorbent polymer 2a ... Are put in the bag without being fixed. ing.

The water-absorbent polymer 2a includes starch-based polymers such as starch-acrylonitrile graft polymer hydrolyzate, cellulose-based polymers such as cellulose-acrylonitrile-grafted polymer, polysaccharides such as hyaluronic acid, proteins such as collagen, poly Polyvinyl alcohol polymer such as vinyl alcohol cross-linked polymer,
Acrylic polymers such as sodium polyacrylate crosslinked polymers, addition polymers such as maleic anhydride polymers, polyether polymers such as polyethylene glycol / diacrylate crosslinked polymers, condensation systems such as ester polymers and amide polymers Polymers can be used.

For the water absorbent paper 2b, pulp or the like that is easily impregnated with water is used. The water-absorbent polymer 2a ... Is impregnated, sandwiched, or attached to the water-absorbent paper 2b.

A woven cloth, a nonwoven cloth or a net is used for the water permeable sheet 2c.

The non-woven fabric is composed of fibers and synthetic resin, and examples of fiber raw materials include rayon, nylon,
Polyester, polyacrylonitrile, polyvinyl chloride, polyolefin, vinylon, etc. are used, and as the synthetic resin raw material, for example, butadiene acrylonitrile resin, vinyl acetate-ethylene copolymer resin, amino resin,
Silicon resin, acrylate resin or the like is used.

Fibers such as nylon, polyester and cotton are used for the woven cloth.

Polypropylene, polyethylene, nylon, polyvinyl chloride or the like is used for the net.

For the water absorbent sheet 2, in addition to the material composed of the water absorbent polymer 2a, the water absorbent paper 2b and the water permeable sheet 2c, a water absorbent material such as urethane or felt can be used.
The point is that it is sufficient if it can absorb water, so that any water-absorbing material can be used.

The conductive film 3 has a structure in which a resin film is attached to one side or both sides of a metal foil such as an aluminum foil. The shape of the holes 3a formed in the conductive film 3 may be circular or rectangular. Diameter of hole 3a is 5m
If it is less than or equal to m, most microwaves from the microwave oven can be shielded. The point is that the conductive film 3 can shield the microwave from the microwave oven and the water vapor can pass through the conductive film 3.
Therefore, as the conductive film 3, a resin film containing a conductive filler may be used.

In the above-mentioned structure, the microwave oven heating sheet 10 in which water is sufficiently absorbed in the water absorbent sheet 2 is used for heating various objects to be heated.

That is, as shown in FIG.
1 is wrapped with the microwave heating sheet 10 and heated in this state by a microwave. At this time, the conductive film 3 is wrapped so as to be on the side of the object to be heated 11. Therefore, the water-impermeable film 1 is on the outside.

The microwave radiated from the microwave oven is
Most of the water in the water absorbent sheet 2 is absorbed. Therefore, the water in the water absorbent sheet 2 is heated, and the object to be heated 11 is heated by heat conduction. Further, the steam passes through the holes 3a formed in the conductive film 3 and steam heating is also performed in parallel. In addition, since the water-impermeable film 2 is provided on the outer side, water vapor is unlikely to escape from the microwave heating sheet 10 to the outside.

As described above, according to the microwave heating sheet 10 of this embodiment, the object 11 to be heated is not directly heated by the microwave but is indirectly heated by heat conduction and steam. Therefore, the object to be heated 11 is uniformly heated from the surroundings and is heated with high thermal efficiency.

Further, since the upper limit of the heating temperature is about 100 ° C., there is no fear of thermal deformation even if the object 11 to be heated is a packaging bag made of a synthetic resin sheet.

Moreover, the microwave from the microwave oven is shielded by the conductive film 3. Therefore, even if the object 11 to be heated is accidentally heated for a long time, the object 11 to be heated is not directly heated in the microwave oven, so that the object 11 to be heated can be prevented from being overheated. This improves safety.

Next, the above microwave heating sheet 10 is used.
The heating experiment using is explained. As the object to be heated 11, a reheater manufactured by Sekisui Plastics Co., Ltd. was used.

The reheater is a wrapping bag made of a heat-resistant synthetic resin sheet such as polyvinyl chloride, in which a solution such as an aqueous solution of sodium acetate that is easily supercooled and a crystallization starter made of a coil spring of metal are included. It has a housed structure, and by pressing the crystallization starter with a finger, crystallization of the above supercooled solution is started, and the heat of crystallization generated at that time is used for heat generation, so that the hot water bottle and health Used as an instrument. After use, if the reheater is heated to melt the crystals, the original supercooled solution is regenerated, so that it can be used repeatedly.

The microwave heating sheet 10 used in the heating experiment is preliminarily processed into a bag shape for convenient handling, as shown in FIG. The outer water-impermeable film 1 is
The handle 1a is made of polyvinyl chloride, and has a long extension at one end to prevent burns and is provided integrally with the bag.
The water absorbent sheet 2 on the inside is made of urethane. The innermost conductive film 3 is made of aluminum foil laminated with resin films on both sides for durability. The diameter of the holes 3a is 3 mm, and the holes 3a and 3
The distance a is about 10 mm.

After absorbing 150 g of water into the water-absorbent sheet 2, a reheater weighing about 300 g is put in the bag of the conductive film 3, and a microwave oven manufactured by Sharp Corporation (model number R
-3600, high frequency output 500 W) and heated for 7 minutes.
Then, after standing for 5 minutes, the microwave heating sheet 10 containing the reheater was taken out from the microwave, and all the crystals in the reheater were melted. Also,
It was confirmed that the handle 1a did not become hot.

As described above, according to the microwave heating sheet 10 of the present invention, the reheater can be safely regenerated in a short time. When the microwave oven heating sheet 10 is processed into a bag, it is necessary to provide a gas vent hole or the like in order to dissipate the internal vapor so as to ensure an open structure.

The microwave oven heating sheet 10 according to the present invention has at least the water-absorbent sheet 2 on the water-impermeable film 1, and the conductive material having the holes 3a having a size capable of shielding the microwave from the microwave oven. The film 3 is laminated.

According to this, when the water-absorbent sheet 2 is made to absorb water, the object 11 is wrapped with the conductive film 3 inside and heated in a microwave oven, the water absorbed in the water-absorbent sheet 2 is heated. To be done. Then, the object to be heated 1 by heat conduction
0 is indirectly heated. Also, the water vapor is the conductive film 3
The steam heating is also performed in parallel through the holes 3a ... As a result, the object to be heated 11 is uniformly heated from the surroundings and is heated with high thermal efficiency. Further, even if it is accidentally heated for a long time, the microwave from the microwave oven is shielded by the conductive film 3. As a result, the article to be heated 11 is not directly heated in the microwave oven, so that the article 11 to be heated can be prevented from overheating.

[0032]

As described above, the microwave heating sheet according to the present invention has at least a water-absorbent sheet on a water-impermeable film, and a conductive material having a hole large enough to shield microwaves from the microwave oven. Since the water-absorbent sheet is laminated with a water-absorbent film, the water-absorbent sheet absorbs water, wraps the object to be heated with the conductive film inside, and when heated in a microwave oven, the water absorbed in the water-absorbent sheet is heated. . Then, the object to be heated is indirectly heated by heat conduction. Further, steam passes through the holes formed in the conductive film, and steam heating is also performed in parallel. As a result, the object to be heated is uniformly heated from the surroundings and is heated with high thermal efficiency.
In addition, even if accidentally heated for a long time, the microwave from the microwave oven is shielded by the conductive film. As a result, the object to be heated is not heated directly by the microwave oven, so that the object to be heated can be prevented from being overheated.

[Brief description of drawings]

FIG. 1 is a vertical cross-sectional view showing a schematic configuration of a microwave heating sheet of the present invention.

2 is a longitudinal sectional view showing an example of a water absorbent sheet in the microwave heating sheet of FIG.

FIG. 3 is an explanatory diagram showing a method of using the microwave heating sheet of FIG.

FIG. 4 is a perspective view showing a microwave heating sheet used in a heating experiment.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Water-impermeable film 1a Handle 2 Water-absorbent sheet 2a Water-absorbent polymer 2b Water-absorbent paper 2c Water-permeable sheet 3 Conductive film 3a Hole 10 Microwave oven heating sheet 11 Heated object

Claims (1)

[Claims] 1. A microwave oven heating, comprising: a water-impermeable sheet, and a conductive film having a hole having a size capable of shielding microwaves from a microwave oven laminated on the water-impermeable film. Sheet.