JPH10117941A - Susceptor laminate for microwave oven - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a susceptor presenting no fear of firing at heating and cooking and excellent in the mold releasing property of the food by furnishing microwave heat emitting layer on the surface of a film-form or sheet-form base material, forming a mold releasing agent on its surface, and lamianating a fire-retardant support to the rear surface of the base material. SOLUTION: A microwave heat emitting layer 2 is furnished on the surface of a film-form or sheet-form base material 3, and a mold releasing agent layer 1 is provided on its surface, and a fire-retardant support 4 is laminated to the rear surface of the base material 3. Examples of a metal evaporation layer as the microwave heat emission layer 2 are an evaporated thin film of aluminum, tin, zinc, iron, copper and a mixture layer of aluminum and aluminum oxide, the latter being more preferred from the viewpoint of the heat emission quantity and spark generation at heating. The mold releasing agent layer 1 functions as releasing mold for food material, favorable example being carnauba wax. The material of the fire-retardant support 4 should favorably be grassine paper, aluminum hydroxide paper, etc.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a susceptor laminate for a microwave oven.

[0002]

2. Description of the Related Art Defrosting and cooking foods in a microwave oven using the principle of microwave heating have been actively performed in recent years because of their convenience, and have become a necessity for daily life. At that time, brown the food to improve the texture and flavor,
For the purpose of assisting the heating itself, a microwave heating element, a so-called microwave susceptor, has attracted attention and has been used. This susceptor is generally provided with a metal thin film or a metal / metal oxide mixture on a plastic film base material such as PET by vapor deposition, and after bonding with a support such as paper,
It is used in the form of being fixed in a food container or wrapping the food itself.

[0003] The susceptor film is bonded to general paper,
When used as a microwave-heated food container or sheet, if the amount of heat generated by microwave irradiation is large, or if the consumer accidentally exceeds the heating time, the bonded paper may ignite in the microwave. . In addition, when a general-purpose adhesive is used for bonding the vapor-deposited film and paper, there is also a problem that a gap between the vapor-deposited film and paper is generated due to insufficient heat resistance of the adhesive. Furthermore, when food is actually heated and cooked using a conventional susceptor, a phenomenon occurs in which the cooked food adheres to the susceptor, and the food in the adhered portion peels off to the susceptor side. Salad oil on the susceptor or on the food itself,
It was necessary to apply a substance that promotes peeling, such as butter.

[0004]

SUMMARY OF THE INVENTION An object of the present invention is to provide a susceptor for a microwave oven which has no fear of ignition at the time of heating and cooking and is excellent in food releasability in terms of industrial production.

[0005]

As a result of intensive studies by the present inventors, the object of the present invention has been industrially advantageously achieved by the following invention.

[1] A microwave heating layer is provided on the surface of a film or sheet-like base material, a release agent layer is formed on the surface, and a flame-retardant support is bonded to the back surface of the base material. Susceptor laminate for microwave oven.

[2] The susceptor laminate for a microwave oven according to the above [1], wherein the release agent layer is a layer formed by coating.

[3] The release agent layer has a thickness of 0.2 to 3.0 μm.
m, wherein the susceptor laminate for a microwave oven according to the above [1] or [2].

[4] The susceptor laminate for a microwave oven as described in any one of [1] to [3] above, wherein the release agent layer is made of carnauba wax.

[5] The susceptor laminate for a microwave oven according to any one of [1] to [4], wherein the microwave heating layer is a mixed vapor-deposited layer of aluminum metal and aluminum oxide.

[6] The flame-retardant support has a basis weight of 20 to 400 g
/ M ^{2, wherein} the susceptor laminate for a microwave oven according to any one of the above [1] to [5], wherein the susceptor laminate is a flame retardant paper.

[0012]

DESCRIPTION OF THE PREFERRED EMBODIMENTS In the present invention, the type of film is not particularly limited as long as it has a metal vapor deposition processing suitability, and may be selected according to the amount of heat to be generated. Typical examples include polyesters such as polyethylene terephthalate, polybutylene terephthalate, and polybutylene 2.6-naphthalate, polyolefins such as polyethylene and polypropylene, polyamides such as 6 nylon and 12 nylon, aromatic polyamides, polyimides, and the like. Films and sheets made of a copolymer of the union and another organic polymer are exemplified. There is no problem even if various additives such as an antistatic agent, a lubricant and an antioxidant are added to the polymer and the copolymer. The thickness of these films is not particularly limited,
6-100 μm when considering the suitability for machining such as vapor deposition
Is desirable.

[0013] Aluminum, tin, zinc,
Although a vapor-deposited thin film of iron, copper, or the like and a mixed layer of aluminum and aluminum oxide are conceivable, it is preferable to use a mixed layer of aluminum and aluminum oxide in view of the calorific value and the problem of spark during heating.

The release agent layer functions as a food release. Examples of the release agent layer include an acrylic resin, a silicone resin, a fluororesin, and carnauba wax, and the use of carnauba wax is most preferable from the viewpoint of food release properties and food hygiene. Carnauba wax is a natural type thermoplastic polymer and may be purified. The formed thickness of the release agent layer is desirably 0.2 μm to 3 μm. This is because if the thickness is less than 0.2 μm, the food peelability is insufficient, and 3 μm
If the thickness is larger than m, the heat generation is absorbed by the release agent layer, which affects the heat generation temperature.

The flame-retardant support has an electric resistance of 10 ⁴ Ω.
It is preferable to use a flame-retardant paper having a melting point of 300 ° C. or higher and having flame retardancy. In particular, it is desirable to use flame-retardant paper such as glassine paper and aluminum hydroxide paper in terms of workability.

In the present invention, a flame-retardant support is attached to the back surface of a film-like or sheet-like substrate, and an adhesive is usually used for this purpose.

The adhesive is not particularly limited as long as it is generally used as a food packaging material such as silicone resin, polyester resin, acrylic resin, and vinyl acetate resin. It is desirable to use silicone resin.

[0018]

【Example】

[Example 1] A biaxially stretched polyethylene terephthalate film having a thickness of 12 µm was coated on one surface of a biaxially stretched polyethylene terephthalate film using a continuous vacuum evaporator at a composition weight ratio of aluminum / aluminum oxide of 1/1, a vapor deposition thickness of 650 Å, and a light beam. It vapor-deposited on condition of the transmittance | permeability of 50%, and provided the metal vapor deposition layer. Next, using a gravure coater as a metal deposition layer, a carnauba wax layer having a thickness of 1 μm was provided as a food release layer. Carnauba wax is applied by dissolving Carnauba No. 1 in toluene heated to 70 to 80 ° C and adjusting the concentration to 4% with MEK.
The coating was performed while maintaining the coating pan at 50 to 60 ° C. Thereafter, the non-food release layer side of the biaxially stretched polyethylene terephthalate film is coated with a silicone adhesive manufactured by Dow Corning Toray Silicone Co., Ltd. using a silicone adhesive manufactured by Miyoshi Paper Co., Ltd. to produce a basis weight of 120 g / m ² hydroxylated. It was bonded to an aluminum paper sunwall to form a susceptor for a microwave oven. Comparative Example 1 and Comparative Example 2
A susceptor for a microwave oven was formed in exactly the same manner as in Example 1 except that kraft paper and white paperboard of / m ² were used. The former was Comparative Example 1 and the latter was Comparative Example 2. Comparative Example 3 A susceptor for a microwave oven was formed as Comparative Example 3 except that the carnauba wax layer was omitted from the structure of Example 1.

With respect to the susceptors for microwave ovens obtained in Example 1 and Comparative Examples 1 to 3, the heat generation temperature under the condition of a high frequency output of 500 W using a microwave oven à la carte ER-630SF manufactured by Toshiba was used to determine the heat label manufactured by Micron Corporation. Table 1 shows the results of the measurement using Table 1. Table 2 shows the results of the visual evaluation of the scorching of the paper surface after heat generation. In addition, Table 3 shows the results of actually placing a pizza (Pizza Pizza) manufactured by Meiji Dairies Co., Ltd. on a susceptor and visually assessing food adhesion after heat generation.

[0020]

[Table 1]

[0021]

[Table 2]

[0022]

[Table 3] In Tables 1 and 2, Comparative Examples 1 and 2, which did not use flame-retardant paper, were unsuitable for practical use in consideration of the danger of ignition, etc., because the paper started to burn after 30 seconds of heating in a microwave oven.

In Table 3, in Comparative Example 3 in which carnauba wax was not used as a food release layer on the vapor deposition layer, pizza adhered to the vapor deposition surface and was difficult to peel off. In Example 1, it was confirmed that there was no scorching of the bonded paper and no occurrence of film / paper gap due to heat generation, and there was no pizza adhesion.

[0024]

As described above, according to the present invention, a non-food release layer surface of a vapor-deposited film provided with a food release layer is bonded to flame-retardant paper using a silicone-based adhesive. A susceptor for a microwave oven is provided which has no scorch of paper and no occurrence of film / paper gap due to heat generation during heating, has no food sticking after heat generation, and has excellent food peelability.

[Brief description of the drawings]

FIG. 1 shows a configuration example of a susceptor for a microwave oven according to the present invention, which is described in an embodiment.

[Explanation of symbols]

1: release agent layer (carnauba wax) 2 ... microwave heating layer (aluminum / aluminum oxide mixed vapor deposition layer) 3 ... plastic film (biaxially stretched polyethylene terephthalate film) 4 ... flame retardant paper (aluminum hydroxide paper)

Claims (6)

[Claims] A microwave heating layer is provided on the surface of a film-shaped or sheet-shaped substrate, a release agent layer is formed on the surface, and a flame-retardant support is attached to the back surface of the substrate. Susceptor laminate for microwave oven. 2. The susceptor laminate for a microwave oven according to claim 1, wherein the release agent layer is a layer formed by coating. 3. The susceptor laminate for a microwave oven according to claim 1, wherein the release agent layer has a thickness of 0.2 to 3.0 μm. 4. The susceptor laminate for a microwave oven according to claim 1, wherein the release agent layer is made of carnauba wax. 5. The susceptor laminate for a microwave oven according to claim 1, wherein the microwave heating layer is a mixed vapor deposition layer of aluminum metal and aluminum oxide. 6. A flame-retardant support having a basis weight of 20 to 400 g / m ^2.
3. The flame-retardant paper of claim 1.
5. The susceptor laminate for a microwave oven according to any one of 5.