JPH0610706U - Oven microwave door panel structure - Google Patents

Abstract

(57) [Summary] [Objective] To provide a door panel structure for an oven microwave oven which is lightweight, low in cost and excellent in durability. A door panel structure attached to an open part of an oven microwave oven main body, wherein a heat-resistant glass, an electromagnetic wave shielding member 12 made of a mesh-coated steel plate, and a silicone adhesive layer 13 are interposed on the electromagnetic wave shielding member 12. Its main part is composed of an adhered polyethylene naphthalate film or an inner transparent body made of a heat-resistant polyethylene terephthalate film.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 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 that is lightweight, low cost and excellent in durability.

[0002]

[Prior art]

 As shown in FIGS. 2 and 3, this type of microwave oven includes an oven microwave oven main body a having an opening a1 on the front side, and a door panel structure b attached to the opening a1 so as to be openable and closable. It is known that the main part is composed of.

As shown in FIG. 4, the conventional door panel structure b has an outer transparent body b1 made of heat-resistant glass and an electromagnetic wave inside the oven microwave oven main body a which is laminated on the outer transparent body b1. An electromagnetic wave shield member b2 made of a coated steel plate provided with a mesh m so as not to leak to the inside of the oven microwave oven a so that the inside of the microwave oven 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 main part was composed of the door frame b5 that holds these members.

However, the door panel structure having such a structure has a drawback that the weight is heavy and the operability is poor, and an expensive heat-resistant glass is required, so that the manufacturing cost is high. It was

Under such a technical background, in a microwave oven not having the above-mentioned oven function, a door panel structure which is lightweight and low in cost as shown in FIG. 5 has been developed.

That is, the door panel structure includes an outer transparent body b1 made of polycarbonate, an electromagnetic wave shield member b2 made of a coated steel plate provided with a mesh m as in the conventional case, and an acrylic adhesive b6 for the electromagnetic wave shield member b2. The inner transparent body b4 made of poly (ethylene terephthalate) film and the door frame b5 holding these are mainly composed of the inner transparent body b4 and polycarbonate or polyethylene terephthalate instead of heat resistant glass. By applying the film, it was possible to reduce its weight and cost.

Regarding an oven microwave oven having an oven function, in Japanese Patent Application No. 3-89390 filed by the present inventors, a polyimide film or a polyparabanic acid film is used as an inner transparent body, which increases weight. We solved the drawback of poor operability. However, although all of these films have excellent transparency, they are not yellow or amber, which makes it inconvenient to observe the condition of food in the microwave oven.

[0008]

[Problems to be solved by the device]

 By the way, when the door panel structure having the above-mentioned structure used in this microwave oven is applied to an oven microwave oven having an oven function as it is, the temperature inside the oven microwave oven body is about 170 ° C to 300 ° C. Yes, the temperature of the acrylic adhesive b6 is much higher than the temperature inside the microwave oven, causing thermal deterioration of the acrylic adhesive b6, causing a decrease in its adhesive strength, and an inner transparent body b4 made of a polyethylene terephthalate film. There is a problem in that the inner transparent body b4 floats and peels off from the electromagnetic wave shield member b2 due to heat shrinkage, which act on each other to make it unusable in a short period of time.

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

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

[0011]

[Means for Solving the Problems]

 That is, the invention according to claim 1 is an oven microwave oven in which a main part is constituted by a laminated body including 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. On the premise of the door panel structure of the above, the inside transparent body is composed of a polyethylene naphthalate film or a heat-resistant polyethylene terephthalate film adhered to the electromagnetic wave shielding member via a silicon adhesive. It is what

In such a technical means, the outer transparent body provided on the outer side of the door panel structure is not exposed to a higher temperature than the inner transparent body, and thus is conventionally applied to the outer transparent body of a microwave oven. Polycarbonate can be applied, and the weight of the material increases, but it is natural that heat-resistant glass can be applied.

Further, as 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]

[Action]

 According to the invention of claim 1, 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 silicone adhesive. Therefore, compared with the conventional door panel structure whose inner transparent body is made of heat-resistant glass, the weight and cost can be reduced.

In addition, the silicone adhesive and the polyethylene naphthalate film or the heat resistant polyethylene terephthalate film have excellent heat resistance, and these films also have a small linear expansion coefficient. Therefore, even if the internal temperature of the oven microwave oven becomes high, heat shrinkage does not easily occur, heat deterioration such as yellowing of the inner transparent body, floating phenomenon from the electromagnetic shield member, and peeling from the electromagnetic shield member. It becomes possible to prevent phenomena. In addition, 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 thread pressure-sensitive adhesive used in the inner transparent body of the present invention is a silicone composition composed of a silicone gum and a silicone resin, which is cross-linked by using a desolvent. Specific examples thereof include trade names “SD 4560”, “SD4570”, and “SD4580” manufactured by Toray Dow Corning Silicone Co., Ltd.

On the other hand, the polyethylene naphthalate film used for the inner transparent body of the present invention has 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 was further improved, and especially the shrinkage rate in the flow direction of the film was 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 its heat resistance is about 170 to 200 ° C. Specific examples 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]

【Example】

 Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 shows a cross-sectional structure of the door panel structure according to the embodiment. The door panel structure 10 includes an outer transparent body 11 made of heat-resistant glass and a mesh laminated on the outer transparent body 11. An electromagnetic wave shield member 12 made of a coated steel plate provided with and a door frame 15 for holding each member such as being adhered to the electromagnetic wave shield member 12 via a silicon adhesive layer 13 constitutes a main part thereof. It is what

[Example 1] A polyethylene naphthalate film (PEN ... trade name Teonex manufactured by Teijin Limited) cut into a thickness of 50 μm and 170 × 320 mm was used as a base material, and a silicon-based adhesive (Toray Dow Corning An inner transparent body 14 made of a polyethylene naphthalate film having a thickness of 50 μm and having a silicon-based adhesive layer 13 formed thereon was obtained by coating with Silicone's trade name SD4560) and drying.

Next, with respect to the electromagnetic wave shield member 12 made of a coated steel plate in which the outer transparent body 11 made of heat-resistant glass is laminated, the inner transparent body 14 is in contact with the electromagnetic wave shield member 12 with the silicon adhesive layer 13 side thereof. Thus, the door panel structure of the oven microwave oven as shown in FIG. 1 was manufactured by mounting the above components and adhering them under pressure, and further fitting these members into the door frame 15.

Example 2 In place of the polyethylene naphthalate film, a heat-resistant polyethylene terephthalate film (PET ... manufactured by Toray Industries, Inc., trade name Lumirror low heat shrink type) was cut to a thickness of 50 μm to 170 × 320 mm. The procedure is substantially the same as that of Example 1 except that the silicon adhesive agent 13 used was SD4580 manufactured by Toray Dow Corning Silicone Co., Ltd. as the silicon adhesive agent to form the silicon adhesive layer 13 having a thickness of 50 μm.

Comparative Example 1 A polyethylene terephthalate film (PET) having a thickness of 50 μm and cut into 170 × 320 mm was used in place of the polyethylene naphthalate film, and acrylic resin was used in place of the silicone adhesive. Example 1 is substantially the same as Example 1 except that a 50 μm thick acrylic adhesive layer was formed by applying a system adhesive.

Comparative Example 2 A polyethylene terephthalate film (PET) having a thickness of 50 μm and cut into 170 × 320 mm was used instead of the polyethylene naphthalate film, and Toray Dow Corning was used as a silicone adhesive. -It is substantially the same as Example 1 except that a silicon adhesive layer having a thickness of 50 µm was formed by applying a trade name SD4580 manufactured by Silicone.

Comparative Example 3 A polyether sulfone film (PES) having a thickness of 50 μm and cut to 170 × 320 mm was used in place of the polyethylene naphthalate film, and Toray Dow was used as a silicon-based adhesive. This is substantially the same as Example 1 except that SD4580, trade name, manufactured by Corning Silicone Co., Ltd. was applied to form a silicon-based adhesive layer having a thickness of 50 μm.

Comparative Example 4 A polyether ether ketone film (PEEK) having a thickness of 50 μm and cut to 170 × 320 mm was used in place of the polyethylene naphthalate film, and Toray Dow was used as a silicone adhesive. This is almost the same as Example 1 except that SD4580 (trade name, manufactured by Corning Silicone Co., Ltd.) is applied to form a 50 μm thick silicon-based adhesive layer.

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 was used as a silicone thread adhesive. The procedure is substantially the same as that of Example 1 except that a product name SD4580 manufactured by Corning Silicone Co., Ltd. is applied to form a silicone thread adhesive layer having a thickness of 50 μm.

[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 an oven microwave oven main body, and For each door panel structure, a time mounting test was performed to check whether the inner transparent body was floating, peeling, heat shrinking, yellowing, etc., and also checking the change in transparency.

The results are shown in Table 1 below.

[0031]

[Table 1]

In the table, “◯” indicates that the inside transparent body did not float, peel off, heat shrink, or yellow, and the transparency does 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, the door panel structures according to the examples do not undergo floating, peeling, heat shrinkage, yellowing, and the like of the inner transparent body, and also have a change in transparency. It was confirmed that there was no change and it was extremely excellent.

On the other hand, in 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. It was confirmed that it cannot be applied.

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 items were the same as those of the example, but the inner transparent body floated, Peeling and heat shrinkage were observed a little and it could not be applied to an oven microwave oven. Also, for the door panel structure according to Comparative Example 4 to which polyetheretherketone (PEEK) was applied, the inner transparent body was not lifted, peeled, and heated. Although the items of shrinkage and yellowing were the same as those of the example, it was confirmed that the transparency was originally extremely poor and it could not be applied to an oven microwave oven.

With respect to the door panel structure according to Comparative Example 5 to which the polyacrylate film (PAR) was applied, peeling, yellowing, and transparency items were the same as those in the example, but the inner transparent body floated, It was confirmed that shrinkage was observed and it could not be applied to the microwave oven.

[0037]

[Effect of device]

 According to the invention of claim 1, compared with the conventional door panel structure whose inner transparent body is made of heat-resistant glass, the weight and the cost can be reduced, so that the operability is improved and the door panel structure is improved. It has the effect that it can be manufactured at low cost.

In addition, the silicone-based adhesive and the polyethylene naphthalate film and the heat-resistant polyethylene terephthalate film that form the internal transparent body have excellent heat resistance, and these films also have a small linear expansion coefficient and the main body of the microwave oven. Since thermal contraction does not easily occur even when the internal temperature of the product rises, prevent thermal 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 Outside Transparent Body 12 Electromagnetic Wave Shielding Member 13 Silicone Adhesive Layer 14 Inside Transparent Body 15 Door Frame

 ─────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Manabu Morihama 1-5-1 Taito, Taito-ku, Tokyo Within Toppan Printing Co., Ltd. (72) Inventor Koichi Hotta 1-5-1 Taito, Taito-ku, Tokyo Toppan Printing Co., Ltd. (72) Inventor Masao Nakajima 1-5-1, Taito, Taito-ku, Tokyo Tokyo Toppan Printing Co., Ltd.

Claims (1)

[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, A door panel structure for an oven microwave oven, wherein the inner transparent body is composed of a polyethylene naphthalate film or a heat-resistant polyethylene terephthalate film adhered to an electromagnetic wave shield member via a silicon adhesive.