JP2504884Y2 - Oven microwave door panel structure - Google Patents

Description

[Detailed description of the device]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a door panel structure for an oven microwave oven, and more particularly to a door panel structure for an oven microwave oven which is lightweight, low cost and excellent in durability.

[0002]

2. Description of the Related Art This type of microwave oven is shown in FIG.
As shown in FIG. 3, it is known that an oven microwave oven main body a having an opening portion a1 on the front side and a door panel structure b attached to the opening portion a1 so as to be openable and closable form a main portion thereof. Has been.

In the conventional door panel structure b, as shown in FIG. 4, an outer transparent body b1 made of heat-resistant glass and an electromagnetic wave in the oven microwave oven main body a which is laminated on the outer transparent body b1 are leaked to the outside. And an electromagnetic wave shield member b2 made of a coated steel plate provided with a mesh m so that the inside of the oven microwave oven main body a can be seen, and an inner transparent body b4 made of heat-resistant glass provided through a space b3 for heat insulation. The door frame b5 for holding each member and the like constitutes the main part thereof.

However, the door panel structure having such a structure has a drawback that it is heavy in weight and poor in operability, and that it requires expensive heat-resistant glass, and thus the manufacturing cost is high.

Under such a technical background, a door panel structure for reducing the weight and the cost as shown in FIG. 5 has been developed for the microwave oven not having the oven function.

That is, this door panel structure is an electromagnetic wave shield member composed of an outer transparent body b1 made of polycarbonate and a coated steel plate provided with a mesh m as in the conventional case.
b2, an inner transparent body b4 made of a polyethylene terephthalate film adhered to the electromagnetic wave shield member b2 via an acrylic adhesive b6, and a door frame for holding these
The main part is composed of b5, and the use of polycarbonate or polyethylene terephthalate film instead of heat-resistant glass made it possible to reduce its weight and cost.

Regarding an oven microwave oven having an oven function, the inventors of the present invention filed Japanese Patent Application No. 3-893.
In No. 90, a polyimide film or a polyparabanic acid film is used as an inner transparent body, which increases weight.
Solved the drawback of poor operability. However, although all of these films are excellent in transparency, they are yellow or amber and therefore inconvenient for observing the condition of food in the oven microwave oven.

[0008]

By the way, when the door panel structure of the above structure used in this microwave oven is directly applied to an oven microwave oven having an oven function, the temperature inside the oven microwave oven main body is The temperature is about 170 ° C to 300 ° C, which is much higher than the temperature inside the microwave oven.
Cause heat deterioration and decrease in its adhesive strength.
The inner transparent body b4 made of a polyethylene terephthalate film also causes heat shrinkage, and these work together to cause the inner transparent body b4 to float from the electromagnetic wave shielding member b2 and peel off to make it unusable in a short period of time. It was

Therefore, as a door panel structure of an oven microwave oven, a structure in which a heat-resistant glass is applied to the inner transparent body is still used, and its weight is heavy, the operability is poor, and the manufacturing cost is high. There was a problem that became.

The present invention has been made in view of these problems, and the problem is to provide a door panel structure for an oven microwave oven which is colorless and transparent, lightweight, low in cost and excellent in durability. To do.

[0011]

[Means for Solving the Problems] That is, the invention according to claim 1 is a main part of a laminated body composed of an inner transparent body, an electromagnetic wave shield member and an outer transparent body, which is openably and closably attached to an open portion of an oven microwave oven main body. , The inner transparent body is adhered to the electromagnetic wave shielding member via a silicone adhesive, and has a low linear expansion coefficient, such as a polyethylene naphthalate film, or a low line. It is characterized by being composed of a heat-resistant polyethylene terephthalate film having an expansion coefficient.

In such a technical means, the outer transparent body provided on the outer side of the door panel structure is not exposed to a high temperature as compared with the inner transparent body, and thus is conventionally applied to the outer transparent body of the microwave oven. Polycarbonate can be applied, and although it is slightly heavier, heat-resistant glass may be applied.

As for the electromagnetic wave shield member, a coated steel plate or the like provided with a mesh can be applied as it is as in the conventional case.

[0014]

According to the first aspect of the invention, the inner transparent body of the door panel structure is made of a polyethylene naphthalate film or a heat-resistant polyethylene terephthalate film adhered to the electromagnetic wave shield member via a silicon adhesive. Therefore, as compared with the conventional door panel structure whose inner transparent body is made of heat-resistant glass, the weight and cost can be reduced.

Further, the silicone adhesive and the polyethylene naphthalate film or the heat-resistant polyethylene terephthalate film have excellent heat resistance, and these films have a small linear expansion coefficient. Therefore, heat shrinkage is unlikely to occur even when the internal temperature of the oven microwave oven becomes high, thermal deterioration such as yellowing of the inner transparent body, floating phenomenon from the electromagnetic wave shield member, and peeling phenomenon from the electromagnetic wave shield member, etc. Can be prevented. Also,
These films are colorless and transparent, and the state of food in the refrigerator can be easily observed like heat-resistant glass.

Here, the silicone adhesive used for the inner transparent body of the present invention is a silicone composition composed of a silicone gum and a silicone resin, which is crosslinked with a catalyst. Specifically, trade names "SD4560" and "SD457" manufactured by Toray Dow Corning Silicone Co., Ltd.
0 ”,“ SD4580 ”and the like.

On the other hand, the polyethylene naphthalate film used for the inner transparent body of the present invention has a heat resistance of about 200 ° C. Specifically, the product name "Teonex" manufactured by Teijin Limited can be used. Regarding the heat-resistant polyethylene terephthalate film, the dimensional stability of ordinary polyethylene terephthalate film is further improved, and especially the shrinkage in the film flow direction is reduced to about 1/3. A heat shrinkage of 0.5% or less in the vertical direction and 0.2% or less in the horizontal direction can be used, and the heat resistance thereof is about 170 to 200 ° C. Specific examples thereof include trade names “Lumirror T56” and “Lumirror S56” manufactured by Toray Industries, Inc.

The door panel structure made of the present film is preferably applied to an oven microwave oven in which the temperature inside the oven microwave oven main body is 200 ° C. or less due to the linear expansion coefficient of the film.

[0019]

Embodiments of the present invention will be described below in detail with reference to the drawings.

FIG. 1 shows a sectional structure of a door panel structure according to the embodiment.
Reference numeral 0 denotes an outer transparent body 11 made of heat-resistant glass, an electromagnetic wave shield member 12 made of a coated steel plate laminated on the outer transparent body 11 and provided with a mesh, and a silicon adhesive layer 13 for the electromagnetic wave shield member 12. The main part is constituted by the door frame 15 that holds each member such as the adhesive bonded via the door frame 15.

[Example 1] A polyethylene naphthalate film (PEN ... trade name Teonex manufactured by Teijin Ltd.) cut to a size of 170 × 320 mm with a thickness of 50 μm was used as a base material, and a silicon-based adhesive (Toray Dow Corning Silicone) was used. The inner transparent body 14 made of a polyethylene naphthalate film on which a silicon-based adhesive layer 13 having a thickness of 50 μm was formed was obtained by applying a product name SD4560) manufactured by the company and drying it.

Next, the outer transparent body 11 made of heat-resistant glass.
The inner transparent body 14 is placed on the electromagnetic wave shielding member 12 made of a coated steel plate laminated so that the silicon-based adhesive layer 13 side is in contact with the electromagnetic wave shielding member 12 and is adhered under pressure. The members were fitted into the door frame 15 to manufacture a door panel structure for an oven microwave oven as shown in FIG.

Example 2 A thickness of 5 was used in place of the polyethylene naphthalate film.
A product made by Toray Dow Corning Silicone Co., Ltd., which uses a heat-resistant polyethylene terephthalate film (PET ... Toray Co., Ltd. product name Lumirror low heat shrink type) cut to 170 × 320 mm with 0 μm. Example 4 is substantially the same as Example 1 except that the SD4580 is applied and the silicon-based adhesive layer 13 having a thickness of 50 μm is formed.

Comparative Example 1 A thickness of 5 was used in place of the polyethylene naphthalate film.
Except for using a polyethylene terephthalate film (PET) cut to 170 × 320 mm with 0 μm and applying an acrylic adhesive instead of the above silicone adhesive to form an acrylic adhesive layer with a thickness of 50 μm. This is almost the same as in the first embodiment.

[Comparative Example 2] A thickness of 5 was used in place of the polyethylene naphthalate film.
A polyethylene terephthalate film (PET) cut to 170 x 320 mm with a thickness of 0 µm is used, and a silicon adhesive layer with a thickness of 50 µm is applied by applying Toray Dow Corning Silicone product name SD4580 as a silicone adhesive. Except for the above, it is substantially the same as in Example 1.

[Comparative Example 3] A thickness of 5 was obtained in place of the polyethylene naphthalate film.
Polyether sulfone film (PES) cut to 170 x 320 mm at 0 µm is used, and a silicone adhesive layer with a thickness of 50 µm using Toray Dow Corning Silicone's product name SD4580 as a silicone adhesive. Example 1 is substantially the same as that of Example 1 except that

[Comparative Example 4] A thickness of 5 was obtained in place of the polyethylene naphthalate film.
Uses polyetheretherketone film (PEEK) cut to 170 x 320 mm at 0 μm, and applies the product name SD4580 made by Toray Dow Corning Silicone Co., Ltd. as a silicon adhesive and has a thickness of 50 μm. Example 1 is substantially the same as that of Example 1 except that

Comparative Example 5 Instead of the polyethylene naphthalate film, a polyacrylate film (PAR) having a thickness of 50 μm and cut into 170 × 320 mm was used, and Toray Dow Corning Made by Silicone
This is almost the same as Example 1 except that the product name SD4580 is applied and a silicon-based adhesive layer having a thickness of 50 μm is formed.

[Confirmation Test] Next, in order to confirm the characteristics of the door panel structure according to each example and the door panel structure according to each comparative example, each of these door panel structures was incorporated into the oven microwave oven main body, and 500 After a time mounting test, for each door panel structure, floating, peeling, heat shrinkage of its inner transparent body,
The presence or absence of yellowing and the like and the change in transparency were also checked.

The results are shown in Table 1 below.

[0031]

[Table 1]

In the table, ◯ means that the inner transparent body did not float, peeled off, heat-shrinked or yellowed, and the transparency did not change. The symbol Δ indicates that floating, peeling, heat shrinkage, and yellowing of the inner transparent body were slightly observed. Regarding x, floating, peeling, heat shrinkage, and yellowing of the inner transparent body were observed, and the transparency was deteriorated.

[Evaluation] As is clear from the results shown in Table 1, in the door panel structures according to the examples, the inside transparent body did not float, peel off, heat shrink, yellow, etc., and change in transparency. It was confirmed that it was extremely excellent.

On the other hand, with respect to the door panel structures according to Comparative Examples 1 and 2, the inner transparent body was greatly floated, peeled off, thermally shrunk and yellowed significantly, and the transparency was also changed. I confirmed that I could not do it.

On the other hand, with respect to the door panel structure according to Comparative Example 3 to which the polyether sulfone film (PES) was applied, the transparency and yellowing change items were the same as those in the Example, but the inner transparent body floated and peeled off. , Heat shrinkage is slightly recognized and cannot be applied to an oven microwave oven, and for the door panel structure according to Comparative Example 4 to which polyetheretherketone (PEEK) is applied, floating, peeling, heat shrinkage of the inner transparent body, Although the yellowing items were the same as those in the example, it was confirmed that the transparency was originally extremely poor and it could not be applied to the microwave oven.

Regarding the door panel structure according to Comparative Example 5 to which the polyacrylate film (PAR) was applied, the peeling, yellowing and transparency items were the same as those of the example, but the inner transparent body floated, and the heat shrinkage occurred. It was confirmed that it was not applicable to the microwave oven.

[0037]

According to the first aspect of the present invention, the inner transparent body can be made lighter and less costly than the conventional door panel structure having the heat-resistant glass, so that the operability is improved. The door panel structure can be manufactured at low cost.

Further, the polyethylene naphthalate film and the heat-resistant polyethylene terephthalate film forming the silicone adhesive and the inner transparent body are excellent in heat resistance, and these films have a small coefficient of linear expansion, and are suitable for the oven microwave oven main body. Since heat shrinkage does not easily occur even when the internal temperature becomes high, it is possible to prevent heat deterioration such as yellowing of the inner transparent body, lifting phenomenon from the electromagnetic wave shield member, and peeling phenomenon from the electromagnetic wave shield member. Therefore, it has the effect of significantly improving the durability of the door panel structure.

[0039]

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a door panel structure of an oven microwave oven according to an embodiment.

FIG. 2 is a perspective view of an oven microwave oven.

FIG. 3 is a perspective view of an oven microwave oven with a door panel structure opened.

FIG. 4 is a cross-sectional view of a door panel structure in a conventional microwave oven.

FIG. 5 is a cross-sectional view of a door panel structure in a conventional microwave oven.

[Explanation of symbols]

 10 Door Panel Structure 11 Outer Transparent Body 12 Electromagnetic Wave Shielding Member 13 Silicone Adhesive Layer 14 Inner Transparent Body 15 Door Frame

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Koichi Hotta, 1-5-1, Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd. (72) Masao Nakajima, 1-5-1, Taito, Taito-ku, Tokyo Toppan printing In-house Examiner, Hiroshi Hayashi (56) Bibliography Sho 60-185107 (JP, U) Fukai 3-31206 (JP, U)

Claims (1)

(57) [Scope of utility model registration request] 1. A door panel structure for an oven microwave oven, the main part of which is a laminated body composed of an inner transparent body, an electromagnetic wave shield member, and an outer transparent body, which is openably and closably attached to an open portion of an oven microwave oven main body, The inner transparent body is composed of a polyethylene naphthalate film having a low linear expansion coefficient, or a heat-resistant polyethylene terephthalate film having a low linear expansion coefficient, which is adhered to the electromagnetic wave shielding member via a silicon adhesive. Oven microwave oven door panel structure characterized by.