JP2007194290A - Flexible wiring board and electronic part - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a flexible wiring board wherein it is possible to avoid thermal damage to an insulation layer and assembling is easy by thermal adhesion. <P>SOLUTION: The one surface of a heat resistance resin layer includes a part wherein a polycarbonate polyurethane resin layer 200 containing an isocyanurate compound as a curing agent and a metal foil layer 32 are stacked in this order. The metal foil layer 32 is patterned. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a flexible wiring board and an electronic component using the same.

  A flexible wiring board has an insulating layer bonded to one side of a copper foil, is flexible and can be bent and used, so it is suitable for wiring in a limited space. There is an advantage that it can be attached to an electronic element of various shapes, and it is used in various electronic devices.

  Usually, general-purpose resins such as polyethylene and polypropylene are used as the insulating layer, but these resins have poor heat resistance and cannot be used for flexible wiring boards that are directly soldered.

  Therefore, heat-resistant resins such as polyimide resins and polyamide-imide resins are used as insulating layers for flexible wiring boards that require heat resistance. However, when a heat resistant resin such as a polyimide resin is used as the insulating layer, the polyimide resin or the like is difficult to be bonded by thermal bonding because of its high heat resistance.

As a means to solve problems related to thermal adhesiveness such as polyimide resin, in a circuit board application, a thermosetting silicone resin is used as an adhesive, a method of adhering polyimide resin (Patent Document 1), an epoxy resin A method of blending as an adhesive and bonding a polyamide-imide resin (Patent Document 2) has been proposed.
However, even in this case, high-temperature and high-pressure pressure bonding is required for thermal bonding, and heat treatment requires high-temperature and long-time treatment as well.
Japanese Patent Publication No. 63-30797 Japanese Patent No. 3223894

  The subject of this invention is the flexible wiring board excellent in the adhesiveness between a metal foil layer and an insulating layer, and the adhesiveness with respect to a target object, and the high performance electronic using this flexible wiring board To provide parts.

  Another object of the present invention is to provide a flexible wiring board capable of avoiding thermal damage to the insulating layer and a high-performance electronic component using the flexible wiring board.

  In order to solve the above-described problems, a flexible wiring board according to the present invention has a metal foil layer adjacent to one side of both sides of a polycarbonate polyurethane resin layer containing an isocyanurate compound as a curing agent, and the metal foil layer is A heat-resistant resin layer containing a polyamideimide resin is adjacent to the other surface that is not adjacent. The metal foil layer is patterned.

  In the flexible wiring board described above, the polycarbonate polyurethane resin layer containing an isocyanurate compound as a curing agent has excellent adhesiveness. Therefore, unlike the conventional case in which only the polyamideimide resin layer is provided on the metal foil layer, the high temperature and high pressure treatment is unnecessary in the adhesion treatment process, and the adhesion treatment process is performed by utilizing the adhesive force of the polycarbonate polyurethane resin layer. Can be completed in a short time.

  Since the metal foil layer is patterned, the portion of the polycarbonate polyurethane resin layer where the metal foil layer is not present can be brought into contact with the object and thermally cured to adhere to a predetermined position of the object. Because. In that case, the polycarbonate polyurethane resin will be lifted from the member of the bonding partner by the thickness of the metal foil layer, but both the polycarbonate polyurethane resin and the polyamideimide resin are flexible, so in the part without the metal foil layer, both resins It is possible for the layer to deform and adhere securely to the object.

  Since the polycarbonate polyurethane resin layer is adjacent to the heat-resistant resin layer containing the polyamideimide resin having high heat resistance on the surface not adjacent to the metal foil layer, the polycarbonate polyurethane resin layer maintains high heat resistance as a whole, and is in a predetermined position. It is possible to avoid thermal damage to the insulating layer at the time of attachment.

  Furthermore, the present invention also discloses a nonreciprocal circuit element such as an electronic component provided with a flexible wiring board, such as an isolator, as one application example of the flexible wiring board described above.

  Further, as the polycarbonate polyurethane resin layer containing the isocyanurate compound as a curing agent, the isocyanurate compound is preferably contained in an amount of 5 to 30 wt% with respect to the polycarbonate polyurethane resin. The polycarbonate polyurethane resin layer exhibits excellent adhesion as described above, but exhibits superior heat resistance and thermal adhesion by the addition of an isocyanurate compound within the above range.

  As the polyamide-imide resin, one having a glass transition temperature of 300 ° C. or higher is more preferable. This is because the polyamide-imide resin having a glass transition temperature of 300 ° C. or higher is excellent in heat resistance during soldering and is particularly suitable for spot soldering. With spot soldering, the temperature of the wiring board is partially close to 300 ° C.

  As the polyamide-imide resin layer, the polyamide-imide resin layer obtained by mixing 2 to 20 wt% of an epoxy resin with respect to the polyamide-imide resin is preferable. This epoxy resin undergoes a cross-linking reaction with an amide group, a carboxyl group or the like in the polyamide-imide resin to form a three-dimensional structure, and heat resistance and chemical resistance are improved. It also has the effect of improving alkali resistance and preventing shrinkage of the resin film. When it exceeds 20 wt%, the heat resistance is lowered. If it is less than 2 wt%, the alkali resistance is not improved, and the shrinkage of the resin film cannot be prevented.

As described above, according to the present invention, the following effects can be obtained.
(1) To provide a flexible wiring board excellent in adhesion between a metal foil layer and an insulating layer and adhesion to an object, and a high-performance electronic component using the flexible wiring board can do.
(2) A flexible wiring board capable of avoiding thermal damage to the insulating layer and a high-performance electronic component using this flexible wiring board can be provided.

  Other objects, configurations and advantages of the present invention will be described in more detail with reference to the accompanying drawings. However, the attached drawings are merely examples.

  FIG. 1 is a diagram schematically showing a cross-sectional structure of a flexible wiring board according to the present invention. Referring to the figure, a polycarbonate polyurethane resin layer 200 and metal foil layers 301 and 302 containing an isocyanurate compound as a curing agent are laminated on one surface of the heat resistant resin layer 100 in this order. The heat-resistant resin layer 100, the polycarbonate polyurethane resin layer 200, and the metal foil layers 301 and 302 are not particularly limited as long as they are selected from the embodiments of the present invention.

  In the flexible wiring board described above, the polycarbonate polyurethane resin layer 200 containing an isocyanurate compound as a curing agent has excellent adhesiveness. Therefore, unlike the conventional case in which only the polyamideimide resin layer is provided on the metal foil layers 301 and 302, the high temperature and high pressure treatment is not required in the adhesion treatment process, and the adhesive force of the polycarbonate polyurethane resin layer 200 is utilized. It is possible to complete the adhesion treatment process in a short time.

  Since the polycarbonate polyurethane resin layer 200 is adjacent to the heat-resistant resin layer 100 containing a polyamideimide resin having high heat resistance, the surface not adjacent to the metal foil layers 301 and 302 maintains high heat resistance as a whole. It is possible to avoid thermal damage to the insulating layer when it is attached to a predetermined position.

  The thickness of the polycarbonate polyurethane resin layer 200 containing the isocyanurate compound as a curing agent, the metal foil layers 301 and 302, or the heat-resistant resin layer 100 containing the polyamideimide resin is not particularly limited, but ranges from 5 μm to 100 μm. Can be selected. Therefore, the flexible wiring board according to the present invention is actually a very thin flexible film or sheet.

  In the polycarbonate polyurethane resin layer 200 containing the isocyanurate compound as a curing agent, the isocyanurate compound serving as the curing agent is preferably contained in the range of 5 wt% to 30 wt% with respect to the polycarbonate polyurethane resin. By including the isocyanurate compound in the range of 5 wt% to 30 wt%, excellent thermal adhesiveness is exhibited. When the addition is less than 5 wt%, the heat resistance is poor, and when the addition exceeds 30 wt%, the later-described blocking (sticking) occurs, making it difficult to form a flexible wiring board.

  In the heat resistant resin layer 100 containing the polyamideimide resin, it is preferable to contain the epoxy resin in the range of 2 to 20 wt% with respect to the polyamideimide resin. The epoxy resin in this range undergoes a cross-linking reaction with an amide group or a carboxyl group in the polyamide-imide resin to form a three-dimensional structure and improve heat resistance and chemical resistance. It also has the effect of improving alkali resistance and preventing shrinkage of the resin film. When it exceeds 20 wt%, the heat resistance is lowered. If it is less than 2 wt%, the alkali resistance is not improved, and the shrinkage of the resin film cannot be prevented.

The polyamideimide resin preferably has a glass transition temperature of 300 ° C. or higher. By using a polyamide-imide resin having a glass transition temperature of 300 ° C. or higher, it becomes excellent in heat resistance in soldering, and particularly suitable for spot soldering.
The metal foil layers 301 and 302 are preferably made of copper foil and are patterned in accordance with the intended use.

  The polycarbonate polyurethane resin layer 200 containing an isocyanurate compound as a curing agent and the heat resistant resin layer 100 containing a polyamideimide resin may contain a ceramic dielectric or magnetic powder or both. Ceramic dielectric powder can be used to improve the apparent relative permittivity, and magnetic powder can be used to improve the relative permeability. As the magnetic powder, ferrite magnetic powder or the like can be used.

  Next, the usage state of the flexible wiring board shown in FIG. 1 will be described with reference to FIG. In FIG. 2, the flexible wiring board 3 is composed of the flexible wiring board according to the present invention described with reference to FIG. 1, with the metal layers 301 and 302 facing the object 4, It is bonded to the outer surface of the object 4. In the present invention, since the metal foil layers 301 and 302 are provided on one surface of the polycarbonate polyurethane resin layer 200 cured using an isocyanurate compound curing agent having both appropriate heat resistance and thermal adhesion, The metal foil layer surface side can be attached to the object 4, and the flexible wiring board can be adhered to a predetermined position of the object 4. In the figure, the part indicated by the bold line is the bonding surface between the object 4 and the polycarbonate polyurethane resin layer 200, and the polycarbonate polyurethane resin layer 200 is bonded together in the contact area.

  In the bonded state, the polycarbonate polyurethane resin layer 200 is lifted from the member to be bonded by the thickness of the metal foil layers 301 and 302. However, the polycarbonate polyurethane resin layer 200 and the heat-resistant resin layer are not formed in the portion without the metal foil layer. Since the insulating resin film composed of 100 is flexible, it can be deformed and bonded on the surface in contact with the object 4.

  In the flexible wiring board, the heat-resistant resin layer 100 and the polycarbonate polyurethane resin layer 200 are adjacent to each other and function as an insulating layer as a whole. The polycarbonate polyurethane resin layer 200 is adjacent to the metal foil layers 301 and 302 that receive heat from the outside during soldering or the like, but the polycarbonate polyurethane resin layer 200 is adjacent to the heat resistant resin layer 100 and is lined. Is in a state. Therefore, the shape is maintained, and as a result, an insulating layer having high heat resistance can be formed.

  The flexible wiring board described above can be generally manufactured by the steps shown in FIGS. First, a polycarbonate polyurethane resin 200 is formed by coating on a metal foil layer 300 made of copper foil and dried. Specifically, a polycarbonate polyurethane resin and an isocyanurate compound added in an amount of 5 to 30 wt% with respect to the polycarbonate polyurethane resin are dissolved in a solvent methyl ethyl ketone (hereinafter referred to as MEK), and a lacquer solution having a concentration of 20 wt% is obtained. Create

  And this lacquer solution is apply | coated using an applicator so that the layer thickness after drying may be set to 5 micrometers on the metal foil layer 300 which consists of copper foil, and it is made to dry.

  Next, a mixed solution of a heat-resistant resin containing polyamideimide resin and a solvent is applied onto the polycarbonate polyurethane resin layer 200 using, for example, an applicator so that the layer thickness after drying is 5 μm, and then dried. Let

  Next, the sheet is subjected to a curing reaction in an environment of 180 to 200 ° C. and 3 to 12 hours.

  Next, a photoresist mask is applied on the metal foil layer 300, photolithography is performed, and resist films 501 and 502 are formed in a desired pattern as shown in FIG. In the photolithography process, an ultraviolet curing process or the like is performed and then an etching process is performed to obtain patterned metal foil layers 301 and 302 as shown in FIG.

  Thereafter, by removing the resist masks 501 and 502, metal foil layers 301 and 302 having a predetermined pattern are formed on the surface of the polycarbonate polyurethane resin layer 200 adjacent to the heat resistant resin layer 100 as shown in FIG. The flexible wiring board material which has is obtained. This is cut into predetermined dimensions to obtain a desired flexible wiring board. Note that the various numerical values, patterns, processes, and the like described above are merely examples for the purpose of specific description, and are not intended to limit the present invention.

  Next, the contents of the present invention will be described more specifically with reference to comparative examples and examples.

Comparative Example 1
Polyamideimide resin (Toyobo Viromax HR14ET solid content concentration: 30 wt% Tg: 250 ° C.) was dissolved using a solvent mixture (weight ratio of ethyl alcohol to toluene 1: 1) to give a 20 wt% concentration. A lacquer solution was prepared, and 5 wt% of epoxy resin (Epofix Resin manufactured by Struers) was added to the polyamideimide resin. This lacquer solution is applied onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12, manufactured by Furukawa Circuit Co., Ltd.) using an applicator so that the layer thickness after drying is 10 μm, and after drying, winding is performed. I took it.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc) 5 cc, mixed solution of 18 g of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)), then mask stripping (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., Time: 1 minute), and a flexible wiring board having a predetermined size was prepared.

  The flexible wiring board obtained in this way was cut into a predetermined size, and in the assembly process, it was sequentially bent and heated, and a structure was produced by thermal bonding. However, the polyamide-imide resin did not adhere even when heated to 280 ° C., but the resin was hard and cracked and the desired product could not be obtained.

Comparative Example 2
A polyimide precursor (RC5057, solid content concentration: 15 wt%, manufactured by IS Corporation) was dried on a 12 μm thick electrolytic copper foil (F1-WS-12, manufactured by Furukawa Circuit Co., Ltd.), and the layer thickness was 10 μm. Then, it was applied using an applicator, dried and wound up. Next, a curing treatment was performed at 300 ° C. for 12 hours.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc) 5 cc, mixed solution of 18 g of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)), then mask stripping (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., (Time: 1 minute), and an attempt was made to create a flexible wiring board having a predetermined size.

  However, in the mask peeling process, it is not clear whether the resistance to the aqueous sodium hydroxide solution used in this process was insufficient, but the resin layer was broken, and a flexible wiring board having a desired size was obtained. I couldn't.

Comparative Example 3
Polyester urethane resin (Toyobo's Byron UR-8700 solid content concentration: 30 wt% Tg: -22 ° C), an isocyanate compound (Coronate L manufactured by Nippon Polyurethane Industry Co., Ltd.) is added by 15 wt%, and further dissolved in a solvent MEK. A lacquer solution having a concentration of 20 wt% was prepared.

  This lacquer solution is applied onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so that the layer thickness after drying becomes 10 μm, and after winding, I took it.

  Next, a curing treatment was performed at 100 ° C. for 12 hours. Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc) 5 cc, pre-posit etch 748 (manufactured by Shipley) 18 g mixed solution), then mask stripping (material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., (Time: 1 minute) to create a flexible wiring board having a predetermined size.

  However, in the mask peeling process, the resin layer was broken and a flexible wiring board having a desired size was not obtained. The cause is considered to be that the polyester urethane resin has an ester group, and thus the resistance to the aqueous sodium hydroxide solution used in this step was insufficient.

Comparative Example 4
Polycarbonate polyurethane resin (N5230, manufactured by Nippon Polyurethane Industry, solid content concentration: 30 wt%, Tg: −33 ° C., softening point: 130 ° C.) is added with 15 wt% of isocyanate compound (Millionate MR200 manufactured by Nippon Polyurethane Industry), and solvent MEK. To prepare a lacquer solution having a concentration of 20 wt%.

  This lacquer solution is applied onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12, manufactured by Furukawa Circuit Co., Ltd.) using an applicator so that the layer thickness after drying is 10 μm, and after drying, winding is performed. I took it.

  Next, a curing treatment was performed at 100 ° C. for 12 hours. Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: Mixed solution of 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc), 5 cc of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)) Mask peeling (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., time : For 1 minute) to produce a flexible wiring board having a predetermined size.

  The flexible wiring board thus obtained was cut into a predetermined size, and in the assembly process, it was sequentially bent and heated, and a structure was formed by thermal bonding.

  However, the heat resistance is insufficient and the wiring pattern is deformed, and a desired structure cannot be obtained.

Comparative Example 5
Polycarbonate polyurethane resin (N5199, manufactured by Nippon Polyurethane Industry, solid content concentration: 30 wt%, Tg: -29 ° C, softening point: 105 ° C) is added with 15 wt% of isocyanate compound (Millionate MR200, manufactured by Nippon Polyurethane Industry Co., Ltd.) and dissolved in solvent MEK. Thus, a lacquer solution having a concentration of 20 wt% was prepared. This lacquer solution is applied onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so that the layer thickness after drying becomes 5 μm, and after drying, winding is performed. I took it.

  Next, this resin solution obtained by adding an epoxy resin (Stoluas Epofix Resin) (5% with respect to polyamideimide resin) to polyamideimide resin (Toyobo's Viromax HR11NN solid content concentration: 15 wt% Tg: 300 ° C.) Then, it was coated on the polycarbonate polyurethane resin layer using an applicator so that the layer thickness after drying was 5 μm, dried, and wound up.

  Next, a curing process was performed at 180 ° C. for 3 hours. Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: Mixed solution of 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc), 5 cc of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)) Mask peeling (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., time : For 1 minute) to produce a flexible wiring board having a predetermined size.

  The flexible wiring board obtained in this manner was cut into a predetermined size, and in the assembly process, the metal foil layer surface side was attached to the object 4 and then subjected to bending heating, thereby producing a structure by thermal bonding. . However, since the heat resistance of the polycarbonate polyurethane resin layer 200 is insufficient and the melt viscosity is low, the polycarbonate polyurethane resin layer 200 cannot be adhered to a predetermined position.

Comparative Example 6
Add 15 wt% of isocyanurate compound (Coronate 2030, manufactured by Nippon Polyurethane Industry) to polycarbonate polyurethane resin (N5230, manufactured by Nippon Polyurethane Industry Co., Ltd., solid content concentration: 30 wt%, Tg: -33 ° C, softening point: 130 ° C). A lacquer solution having a concentration of 20 wt% was prepared.

  This lacquer solution was applied onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) by using an applicator so that the layer thickness would be 10 μm after drying, and wound after winding.

  Next, a curing treatment was performed at 100 ° C. for 12 hours. Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Materials: Mixed solution of 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc), 18 g of pre-posit etch 748 (manufactured by Shipley)).

  Subsequently, mask peeling (material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., time: 1 minute) was performed to prepare a flexible wiring board having a predetermined size. The flexible wiring board obtained in this way was cut to a predetermined size, and then heated by bending, and a structure was created by thermal bonding, but although it can be bonded, the deformation of the wiring board is large, and the desired structure is It was not obtained.

Example 1
15% by weight of an isocyanurate compound (Coronate 2030, manufactured by Nippon Polyurethane Industry) is added to a polycarbonate polyurethane resin (N5199, manufactured by Nippon Polyurethane Industry Co., Ltd., solid content concentration: 30 wt%, Tg: -29 ° C., softening point: 105 ° C.), and a solvent. A 20 wt% concentration lacquer solution was prepared by dissolving with MEK. This resin solution is applied onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12, manufactured by Furukawa Circuit Co., Ltd.) using an applicator so that the layer thickness after drying is 5 μm, and is dried. I took it.

  Next, this resin solution obtained by adding an epoxy resin (Stoluas Epofix Resin) (5 wt% with respect to the polyamideimide resin) to polyamideimide resin (Toyobo Viromax HR11NN solid content concentration: 15 wt% Tg: 300 ° C.) On the polycarbonate polyurethane resin layer, it was applied with an applicator so that the layer thickness after drying was 5 μm, dried, and then wound up. Subsequently, the curing process was performed at 180 degreeC for 3 hours.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: Mixed solution of 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc), 5 cc of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)) Mask peeling (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., time : For 1 minute) to produce a flexible wiring board having a predetermined size.

  The flexible wiring board obtained in this way is cut into a predetermined size, and in the assembly process, the metal foil layer surface side is attached to the object 4, and the structure is formed by thermal bonding by sequentially bending and heating. Created.

Example 2
15% by weight of an isocyanurate compound (Coronate HX, manufactured by Nippon Polyurethane Industry Co., Ltd.) is added to a polycarbonate polyurethane resin (N5230, manufactured by Nippon Polyurethane Industry Co., Ltd., solid content concentration: 30 wt%, Tg: −33 ° C., softening point: 130 ° C.), and the solvent is MEK. A lacquer solution having a concentration of 20 wt% was prepared by dissolution.

  The obtained lacquer solution was applied onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so that the layer thickness after drying was 5 μm, and dried. Winded up.

  Next, this resin solution obtained by adding an epoxy resin (Stoluas Epofix Resin) (5 wt% with respect to the polyamideimide resin) to polyamideimide resin (Toyobo Viromax HR11NN solid content concentration: 15 wt% Tg: 300 ° C.) On the polycarbonate polyurethane resin layer, it was applied with an applicator so that the layer thickness after drying was 5 μm, dried, and wound up. Subsequently, the curing process was performed at 180 degreeC for 3 hours.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: Mixed solution of 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc), 5 cc of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)) Mask peeling (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., time : For 1 minute) to produce a flexible wiring board having a predetermined size.

  The flexible wiring board obtained in this way is cut to a predetermined size, and in the assembly process, the metal foil layer surface side is attached to the object 4 and then bent and heated in order, and a structure is created by thermal bonding. did.

Example 3
15% by weight of an isocyanurate compound (Coronate 2030, manufactured by Nippon Polyurethane Industry) is added to polycarbonate polyurethane resin (N5230, manufactured by Nippon Polyurethane Industry Co., Ltd., solid content concentration: 30 wt%, Tg: −33 ° C., softening point: 130 ° C.), and solvent MEK. Was dissolved to prepare a lacquer solution having a concentration of 20 wt%.

  The obtained lacquer solution was applied onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so that the layer thickness after drying was 5 μm, and dried. Winded up.

  Next, this resin solution obtained by adding an epoxy resin (Stoluas Epofix Resin) (5 wt% with respect to the polyamideimide resin) to polyamideimide resin (Toyobo Viromax HR16NN solid content concentration: 15 wt% Tg: 320 ° C.) On the polycarbonate polyurethane resin layer, it was applied with an applicator so that the layer thickness after drying was 5 μm, dried, and wound up. Subsequently, the curing process was performed at 180 degreeC for 3 hours.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc) 5 cc, mixed solution of 18 g of pre-posite etch 748 (manufactured by Shipley Co., Ltd.)), then mask stripping (material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., Time: 1 minute), and a flexible wiring board having a predetermined size was prepared.

  The flexible wiring board obtained in this way is cut to a predetermined size, and in the assembly process, the metal foil layer surface side is attached to the object 4, and the structure is formed by thermal bonding by sequentially bending and heating. did.

Example 4
5% by weight of isocyanurate compound (Coronate 2030, manufactured by Nippon Polyurethane Industry) is added to polycarbonate polyurethane resin (N5230, manufactured by Nippon Polyurethane Industry Co., Ltd., solid content concentration: 30 wt%, Tg: −33 ° C., softening point: 130 ° C.), and solvent MEK. Was dissolved to prepare a lacquer solution having a concentration of 20 wt%.

  After applying the obtained lacquer solution onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so as to have a layer thickness of 5 μm after drying. Wound up.

  Next, this resin solution in which an epoxy resin (Epofix Resin manufactured by Struers) (5 wt% with respect to the polyamideimide resin) is added to polyamideimide resin (Toyobo Viromax HR16NN solid concentration: 15 wt% Tg: 320 ° C.) Was coated on the polycarbonate polyurethane resin layer using an applicator so that the layer thickness after drying was 5 μm, dried, and wound up. Subsequently, the curing process was performed at 180 degreeC for 3 hours.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc) 5 cc, mixed solution of 18 g of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)), then mask stripping (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., Time: 1 minute), and a flexible wiring board having a predetermined size was prepared.

  The flexible wiring board obtained in this way is cut to a predetermined size, and in the assembly process, the metal foil layer surface side is attached to the object 4 and then bent and heated in order, and a structure is created by thermal bonding. did.

Example 5
Polyisocyanate polyurethane resin (N5230 made by Nippon Polyurethane Industry, solid content concentration: 30wt% Tg: -33 ° C, softening point: 130 ° C), isocyanurate compound (Coronate 2030 made by Nippon Polyurethane Industry) was added 30wt%, and solvent MEK Dissolved to make a lacquer solution with a concentration of 20 wt%.

  After applying the obtained lacquer solution onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so as to have a layer thickness of 5 μm after drying. Wound up.

  Next, this resin solution obtained by adding an epoxy resin (Stoluas Epofix Resin) (5 wt% to the polyamideimide resin) to polyamideimide resin (Toyobo Viromax HR16NN solid content concentration: 15 wt% Tg: 320 ° C.) On the polycarbonate polyurethane resin layer, it was applied with an applicator so that the layer thickness after drying was 5 μm, dried, and then wound up. Subsequently, the curing process was performed at 180 degreeC for 3 hours.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc) 5 cc, organic peroxide Preposit etch 748 (manufactured by Shipley Co., Ltd.) 18 g), and then the mask was peeled off. (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., time: 1 minute) was performed to prepare a flexible wiring board having a predetermined size.

  The flexible wiring board thus obtained was cut into a predetermined size, and in the assembling process, the metal foil layer surface side was attached to the object 4, and the structure was formed by thermal bonding by sequentially bending and heating. .

Example 6
10 wt% of an isocyanurate compound (Coronate 2030 manufactured by Nippon Polyurethane Industry) is added to a polycarbonate polyurethane resin (N5230 manufactured by Nippon Polyurethane Industry, solid content concentration: 30 wt%, Tg: −33 ° C., softening point: 130 ° C.), and a solvent. A 20 wt% concentration lacquer solution was prepared by dissolving with MEK.

  After applying the obtained lacquer solution onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so as to have a layer thickness of 5 μm after drying. Wound up.

  Next, this resin solution obtained by adding an epoxy resin (Stoluas Epofix Resin) (5 wt% with respect to the polyamideimide resin) to polyamideimide resin (Toyobo Viromax HR16NN solid content concentration: 15 wt% Tg: 320 ° C.) On the polycarbonate polyurethane resin layer, it was applied with an applicator so that the layer thickness after drying was 5 μm, dried, and then wound up. Subsequently, the curing process was performed at 180 degreeC for 3 hours.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc) 5 cc, mixed solution of 18 g of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)), then mask peeling (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., Time: 1 minute), and a flexible wiring board having a predetermined size was prepared.

  The flexible wiring board obtained in this way is cut to a predetermined size, and in the assembly process, the metal foil layer surface side is attached to the object 4 and then bent and heated in order, and a structure is created by thermal bonding. did.

Example 7
10 wt% of an isocyanurate compound (Coronate 2030 manufactured by Nippon Polyurethane Industry) is added to a polycarbonate polyurethane resin (N5230 manufactured by Nippon Polyurethane Industry, solid content concentration: 30 wt%, Tg: −33 ° C., softening point: 130 ° C.), and a solvent. A 20 wt% concentration lacquer solution was prepared by dissolving with MEK.

  After applying the obtained lacquer solution onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so as to have a layer thickness of 5 μm after drying. Wound up.

  Next, this resin solution obtained by adding an epoxy resin (Stoluas Epofix Resin) (2 wt% with respect to the polyamideimide resin) to polyamideimide resin (Toyobo Viromax HR16NN solid content concentration: 15 wt% Tg: 320 ° C.) On the polycarbonate polyurethane resin layer, it was applied with an applicator so that the layer thickness after drying was 5 μm, dried, and then wound up. Subsequently, the curing process was performed at 180 degreeC for 3 hours.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc) 5 cc, mixed solution of 18 g of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)), then mask stripping (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., Time: 1 minute), and a flexible wiring board having a predetermined size was prepared.

  The flexible wiring board obtained in this way is cut to a predetermined size, and in the assembly process, the metal foil layer surface side is attached to the object 4 and then bent and heated in order, and a structure is created by thermal bonding. did.

Example 8
10 wt% of isocyanurate compound (Coronate 2030, manufactured by Nippon Polyurethane Industry) is added to polycarbonate polyurethane resin (N5230, manufactured by Nippon Polyurethane Industry Co., Ltd., solid content concentration: 30 wt%, Tg: −33 ° C., softening point: 130 ° C.), and solvent A 20 wt% concentration lacquer solution was prepared by dissolving with MEK.

  After applying the obtained lacquer solution onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so as to have a layer thickness of 5 μm after drying. Wound up.

  Next, this resin solution obtained by adding an epoxy resin (Stoluas Epofix Resin) (20 wt% with respect to the polyamideimide resin) to polyamideimide resin (Toyobo Viromax HR16NN solid content concentration: 15 wt% Tg: 320 ° C), On the polycarbonate polyurethane resin layer, it was applied using an applicator so that the layer thickness after drying was 5 μm, dried, and wound up. Subsequently, the curing process was performed at 180 degreeC for 3 hours.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc) 5 cc, mixed solution of 18 g of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)), then mask peeling (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., Time: 1 minute), and a flexible wiring board having a predetermined size was prepared.

  The flexible wiring board obtained in this way is cut to a predetermined size, and in the assembly process, the metal foil layer surface side is attached to the object 4, and the structure is formed by thermal bonding by sequentially bending and heating. did.

In Table 1, the composition which comprises the 1st layer and the 2nd layer is shown about each of Examples 1-8 and Comparative Examples 1-6 mentioned above.

次に、表２に、比較例１〜６、及び、実施例１〜８について、アルカリ剥離性、熱接着性、取り扱い性を評価した結果を示す。表２において、アルカリ剥離性は、１０ｗｔ％の水酸化ナトリウム水溶液(４０℃)に１時間浸漬し、樹脂の溶解または樹脂層の破れを目視で判断した。○印は変化なしを示し、×印は樹脂の溶解または樹脂層の破れが見られたことを示す。

Next, Table 2 shows the results of evaluating alkali peelability, thermal adhesiveness, and handleability for Comparative Examples 1 to 6 and Examples 1 to 8. In Table 2, the alkali peelability was determined by immersing in a 10 wt% aqueous sodium hydroxide solution (40 ° C.) for 1 hour, and visually judging whether the resin was dissolved or the resin layer was broken. A circle indicates that there is no change, and a cross indicates that the resin is dissolved or the resin layer is broken.

Thermal adhesiveness was determined by overlapping flexible wiring boards and heating to 280 ° C. with a load of 100 g / cm ² , and then confirming the adhesive strength. X indicates that the film was peeled off with a slight force, △ indicates that the melt viscosity is low and the bonding position is not stable, or the wiring pattern is deformed, and the mark indicates that the bonding position is stable and cannot be easily peeled off. It is shown that. The handleability was observed by visually observing cracks by bending by hand. The symbol ◎ indicates that it is very easy to handle, the symbol ◯ indicates that there is no crack or the like, and the symbol X indicates that a crack has occurred.

表２に示すとおり、実施例１〜８の何れも、比較例１〜６との対比において、良好なアルカリ剥離性、熱接着性及び取り扱い性を示す。

As shown in Table 2, all of Examples 1 to 8 exhibit good alkali peelability, thermal adhesiveness, and handleability in comparison with Comparative Examples 1 to 6.

  In addition, when 50 wt% or more of the isocyanurate compound added to the polycarbonate polyurethane resin in the production of the second layer is added to the polycarbonate polyurethane resin, it is applied on the polyamideimide resin, wound up, and then unwound after being unwound. It is expected that blocking (adhesion) occurs between the layer and the copper foil and the film is torn. On the other hand, in the case of addition of 5 wt% or less, the heat resistance is remarkably inferior, the viscosity at the time of melting becomes low, and it cannot be adhered to a predetermined position.

  Next, the relationship between the glass transition temperature (Tg) and the thermal adhesiveness will be specifically described with reference to Examples 9 and 10.

Example 9
15% by weight of an isocyanurate compound (Coronate 2030, manufactured by Nippon Polyurethane Industry) is added to polycarbonate polyurethane resin (N5230, manufactured by Nippon Polyurethane Industry Co., Ltd., solid content concentration: 30 wt%, Tg: −33 ° C., softening point: 130 ° C.), and the solvent MEK is used. Dissolve to make a 20 wt% lacquer solution. This lacquer solution is applied onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so that the layer thickness after drying is 5 μm, and after drying, winding is performed. It was.

  Next, this resin solution obtained by adding an epoxy resin (Stoluas Epofix Resin) (5 wt% with respect to the polyamideimide resin) to a polyamideimide resin (Toyobo Viromax HR17NN solid content concentration: 35 wt% Tg: 230 ° C.) On the polycarbonate polyurethane resin layer, it was applied with an applicator so that the layer thickness after drying was 5 μm, dried, and wound up. Next, a curing treatment at 100 ° C. for 12 hours was performed.

  Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: Mixed solution of 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc), 5 cc of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)) Mask peeling (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., time : For 1 minute) to produce a flexible wiring board having a predetermined size. The flexible wiring board thus obtained was cut to a predetermined size, the metal foil layer surface side was attached to the object 4, and the structure was formed by heat-bonding in order, and bonding was performed. Although it was possible, the deformation of the wiring board at the time of thermal bonding was great, and it was extremely difficult to produce a desired structure.

Example 10
15% by weight of an isocyanurate compound (Coronate 2030, manufactured by Nippon Polyurethane Industry) is added to polycarbonate polyurethane resin (N5230, manufactured by Nippon Polyurethane Industry Co., Ltd., solid content concentration: 30 wt%, Tg: −33 ° C., softening point: 130 ° C.), and the solvent MEK is used. Dissolve to make a 20 wt% lacquer solution. This lacquer solution is applied onto an electrolytic copper foil having a thickness of 12 μm (F1-WS-12 manufactured by Furukawa Circuit Co., Ltd.) using an applicator so that the layer thickness after drying is 5 μm, and after drying, winding is performed. It was.

Next, this resin solution obtained by adding an epoxy resin (Stoluas Epofix Resin) (5 wt% with respect to the polyamideimide resin) to a polyamideimide resin (Toyobo Viromax HR85ET solid content concentration: 25 wt% Tg: 150 ° C.) On the polycarbonate polyurethane resin layer, it was applied with an applicator so that the layer thickness after drying was 5 μm, dried, and wound up. Next, a curing treatment at 100 ° C. for 12 hours was performed.
Next, a photoresist dry film (Photec RY-3215 manufactured by Hitachi Chemical Co., Ltd.) was laminated on the metal copper surface side, and a predetermined pattern was exposed with a high-pressure mercury lamp. Next, it developed by spraying the anhydrous sodium carbonate aqueous solution (0.8 wt%). Next, the metal copper surface was etched for 30 minutes. (Material: Mixed solution of 400 cc of water, 5 cc of sulfuric acid (specific gravity 1.84 g / cc), 5 cc of pre-posit etch 748 (manufactured by Shipley Co., Ltd.)) Mask peeling (Material: sodium hydroxide aqueous solution (2 wt%), 50 ° C., time : For 1 minute) to produce a flexible wiring board having a predetermined size. The flexible wiring board thus obtained was cut to a predetermined size, the metal foil layer surface side was attached to the object 4, and the structure was formed by heat-bonding in order, and bonding was performed. Although it was possible, the deformation of the wiring board at the time of thermal bonding was large, and it was extremely difficult to produce a desired structure.

  Table 3 below shows the composition components constituting the first and second layers for each of Examples 9 and 10 described above.

次に、表４は、実施例１〜８、及び、実施例９、１０について、アルカリ剥離性、熱接着性、取り扱い性を評価した結果を示す。アルカリ剥離性、熱接着性、取り扱い性については表２に記載されたものと同様の意味を有し、評価の○、△、×も同様の評価を表す。

Next, Table 4 shows the results of evaluating the alkali peelability, thermal adhesiveness, and handleability of Examples 1 to 8 and Examples 9 and 10. About alkali peelability, thermal adhesiveness, and handleability, it has the same meaning as what was described in Table 2, and (circle), (triangle | delta), and x of evaluation represent the same evaluation.

  In addition, although Example 1-8 was described in duplicate with Table 2, it is for the comparison with Example 9, 10, and evaluation is not different from what was described in Table 2.

上記の表４より、実施例９、１０は、アルカリ剥離性、取り扱い性については良評価である。しかし、熱接着性について実施例１〜８と対比をすると、評価は低い。これはガラス転移温度の差異によると考えられる。つまり、好ましいガラス転移温度の範囲は、３００度以上である。

From said Table 4, Example 9, 10 is good evaluation about alkali peelability and a handleability. However, when the thermal adhesiveness is compared with Examples 1 to 8, the evaluation is low. This is thought to be due to the difference in glass transition temperature. That is, the preferable glass transition temperature range is 300 degrees or more.

  Further, an electronic component using the flexible wiring board according to the present invention will be described taking a non-reciprocal circuit element as an example. FIG. 7 is an exploded perspective view showing an example of a non-reciprocal circuit device. The nonreciprocal circuit element shown in the figure includes a case member 1, a cover member 9, an electrical component, and a magnetic component, and constitutes an isolator. The case member 1 includes a magnetic metal portion 10 having electrical conductivity and an electrically insulating resin portion 11 and is formed in a box shape having an open top, and electrical components such as chip capacitors C1 to C3 and a chip resistor R, The magnetic rotor 2 and the permanent magnet are accommodated. A ground conductor 13 is provided at the bottom of the case member 1, and terminal portions 15 and 17 are provided on the electrically insulating resin portion 11.

  The cover member 9 is made of a magnetic metal material having conductivity, overlaps with the permanent magnet 7, is combined with the case member 1 so as to close the opening of the case member 1, and is magnetically coupled to the magnetic metal portion 10 of the case member 1. To form a yoke. The permanent magnet 7 faces the magnetic rotor 2 and applies a DC magnetic field to the magnetic rotor 2.

  The overall component arrangement and the electrical connection relationship are not limited to those shown in FIG. The illustrated nonreciprocal circuit element is characterized in that the flexible wiring board according to the present invention is applied to the portion of the central electrode constituting the magnetic rotor 2 in the general structure described above. Next, this point will be described.

  8 is a plan view showing an example of the magnetic rotor 2, and FIG. 9 is a sectional view taken along line 9-9 of FIG. The illustrated magnetic rotor 2 includes a flexible wiring board 3 and a soft magnetic substrate 4. The soft magnetic substrate 4 is preferably a soft magnetic material such as yttrium / iron / garnet (YIG). The external shape is arbitrary. In the figure, the soft magnetic substrate 4 is formed in a rectangular flat plate shape.

  The flexible wiring board 3 has a metal foil layer 32 constituting a central electrode on one surface of a flexible insulating layer 31, and is attached to the outer surface of the soft magnetic substrate 4. This flexible wiring board 3 is composed of the flexible wiring board according to the present invention described with reference to FIGS. This is a feature of this nonreciprocal circuit device. In this example, the flexible wiring board 3 is attached to the soft magnetic substrate 4 with the surface on which the metal foil layer 32 is formed inside. The insulating layer 31 is composed of a polycarbonate polyurethane resin layer containing an isocyanurate compound as a curing agent and a polyamideimide resin layer, and has a slightly larger pattern in accordance with the metal foil layer 32.

  As shown in FIGS. 8 and 9, in this case, between the adjacent central conductor portions 321 to 322 and between the central conductor portions 322 to 323, there are insulating layers 31 made of a polycarbonate polyurethane resin layer and a heat resistant resin layer. Therefore, the overlapping central conductor portions 321 to 322 and the central conductor portions 322 to 323 are insulated from each other by the insulating layer 31 at the intersections. Therefore, unlike the prior art, it is not necessary to individually sandwich a dedicated insulating sheet or apply an insulator to the intersecting portions of the central conductor portions 321, 322, and 323. For this reason, the insulation process of an intersection part becomes easy.

  In addition, since the insulating layer 31 having a constant thickness is interposed at the intersecting portions of the overlapping central conductor portions 321 to 322 and 322 to 323, the distance between the central conductor portions 321 to 323 with respect to the soft magnetic base 4 is insulative. A constant value depending on the thickness of the layer 31 is maintained, and the characteristics are stabilized.

  The insulating layer 31 is made of a polycarbonate polyurethane resin layer and a heat-resistant resin layer, and can be essentially thin, so that the difference in distance between the central conductor portions 321 to 323 relative to the soft magnetic substrate 4 can be reduced. Therefore, a non-reciprocal circuit device having excellent electrical characteristics can be provided.

  Furthermore, the insulating layer 31 is composed of a polycarbonate polyurethane resin layer containing an isocyanurate compound as a curing agent and a heat-resistant resin layer, and exhibits weldability and adhesiveness by heating at around 280 ° C. Therefore, while electrically insulating the whole of the central conductor portions 321 to 323 with the insulating layer 31, the center conductor portions 321 to 323 can be reliably fixed while maintaining the predetermined crossing angle. .

  A specific configuration of the flexible wiring board 3 described above is illustrated in FIGS. 10 and 11. 10 is a development view of the flexible wiring board 3, and FIG. 11 is a sectional view taken along the line 11-11 in FIG.

  The insulating layer 31 constituting the flexible wiring board 3 is preferably an electrically insulating material that is used in a high frequency region and has little loss. In addition to this, it is more desirable to have thermal adhesiveness. In this embodiment, the insulating layer 31 is composed of a polycarbonate polyurethane resin layer containing an isocyanurate compound as a curing agent and a polyamideimide resin layer, and satisfies a low loss at high frequencies. And the polycarbonate polyurethane resin layer containing an isocyanurate compound as a hardening | curing agent shows sufficient thermal adhesiveness at 280 degreeC. This temperature is higher than the solder reflow temperature of 260 ° C. in the assembly of the non-reciprocal circuit element described later, and is not melted in the reflow furnace. Therefore, the characteristics required for this type of flexible wiring board 3 can be satisfied almost perfectly. When ferrite magnetic powder is contained in the polycarbonate polyurethane resin layer or the heat resistant resin layer, the relative magnetic permeability characteristics of the magnetic rotor 2 can be improved.

  The metal foil layer 32 corresponds to the metal foil layers 301 and 302 in FIGS. 1 to 6 and is formed by etching the copper foil. The metal foil layer 32 may have a general pattern in this type of nonreciprocal circuit device. That is, the pattern has a common electrode part 320 and a plurality of central conductor parts 321 to 323 extending from the common electrode part 320, and the central conductor parts 321 to 323 are arranged so as to intersect each other at a predetermined angle. One end of each of the central conductor portions 321 to 323 is continuous with the common electrode portion 320, and the other end constitutes terminal portions 331 to 333.

  In the illustrated flexible wiring board 3, the insulating layer 31 has a similar planar shape larger than the outer shape pattern of the metal foil layer 32, and has an edge portion that extends outward over the entire circumference of the metal foil layer 32. However, it does not necessarily have to be similar. For example, the non-similar shape such as a shape in which the edge of the insulating layer 31 is partially cut out may be used.

  As shown in FIGS. 10 and 11, the flexible wiring board 3 has the metal foil layer 32 constituting the center electrode on one surface of the insulating layer 31. Mechanical reinforcement is obtained. For this reason, even when the magnetic rotor 2 is reduced in size and thickness, the metal foil layer 32 is reinforced by the insulating layer 31, and as the flexible wiring board 3, sufficient mechanical strength can be secured. Assembling becomes easy and reliability after assembling is also increased.

  In addition, since the insulating layer 31 has flexibility, the insulating layer 31 is attached to the outer surface of the soft magnetic substrate 4 by using a method such as folding the insulating layer 31 along the soft magnetic substrate 4. The magnetic rotor 2 can be configured.

  Next, a method for attaching the flexible wiring board 3 to the soft magnetic substrate 4 will be described with reference to FIGS. When attaching the flexible wiring board 3 to the soft magnetic substrate 4, first, as shown in FIG. 12, the soft magnetic substrate 4 is disposed on the surface of the common electrode portion 320 of the flexible wiring board 3.

  Next, as shown in FIG. 13, the central conductor portion 321 is folded along the outer surface of the soft magnetic substrate 4. Since the insulating film constituting the flexible wiring board 3 is a flexible thin film, the center conductor portion 321 is bent from the lower right to the upper left in FIG. 13 according to its shape.

  Next, as shown in FIG. 14, the central conductor portion 322 is bent along the outer surface of the soft magnetic substrate 4. The central conductor portion 322 is bent in the direction from the lower left to the upper right in FIG. 14 according to the shape thereof, and intersects the central conductor portion 321 at an intermediate portion thereof.

  Next, as shown in FIG. 15, the central conductor portion 323 is bent along the outer surface of the soft magnetic substrate 4. According to the shape, the center conductor portion 323 is bent from the center upper portion toward the center lower portion in FIG. 15, and intersects the center conductor portion 322 at an intermediate portion thereof.

  As a result, the magnetic rotor 2 having the flexible wiring board 3 attached to the outer side so that the surface on which the metal foil layer 32 of the flexible wiring board 3 is formed is placed inside and the soft magnetic substrate 4 is wrapped is obtained. It is done.

  FIG. 16 is an electric circuit diagram of a non-reciprocal circuit device incorporating the magnetic rotor 2 shown in FIGS. 8 to 15. When the magnetic rotor 2 shown in FIGS. 8 to 15 is used, the terminal portions 331 to 333 of the central conductor portions 321 to 323 are connected to the chip capacitors C1 to C3 and the chip in the incorporation into the non-reciprocal circuit element of FIG. Since it faces the resistor R, it is easy to connect the terminal portions 331 to 333 of the central conductor portions 321 to 323 and the chip capacitors C1 to C3 and the chip resistor R.

The terminal portions 331 to 333 of the central conductor portions 321 to 323 are connected to the chip capacitors C1 to C3 and the chip resistor R by soldering. At the time of soldering, the solder melting temperature is directly applied to the terminal portions 331 to 333 of the central conductor portion 321, but as described with reference to FIGS. 1 to 6, the polycarbonate polyurethane containing the isocyanurate compound The resin layer becomes a surface layer by an etching process for patterning the metal foil layer, has a function of heat bonding, and is adjacent to the heat resistant resin layer, so that the shape can be maintained.
Further, in terms of dimensions, the polycarbonate polyurethane resin layer is lifted from the soft magnetic substrate 4 to be bonded by the thickness of the metal foil layer 32, but the portion without the metal foil layer 32 becomes a flexible resin film. Therefore, it can be deformed and bonded.

  The present invention has been described in detail with reference to the preferred embodiments. However, the present invention is not limited to these embodiments, and various modifications can be made by those skilled in the art based on the basic technical idea and teachings. It is self-evident that

It is a figure which shows typically the cross-sectional structure of the flexible wiring board which concerns on this invention. It is a figure which shows the use condition of the flexible wiring board shown in FIG. It is a figure which shows the manufacturing process of the flexible wiring board shown in FIG. FIG. 4 is a diagram showing a step after the step shown in FIG. 3. It is a figure which shows the process after the process shown in FIG. FIG. 6 is a diagram showing a step after the step shown in FIG. 5. It is a disassembled perspective view of the nonreciprocal circuit device according to the present invention. It is a top view of the magnetic rotor used for the nonreciprocal circuit element shown in FIG. FIG. 9 is a sectional view taken along line 9-9 in FIG. 8. It is an expanded view of the flexible wiring board used for the magnetic rotor shown in FIG. It is the 11-11 line sectional view of FIG. It is a figure which shows the magnetic rotor assembly process using the flexible wiring board shown in FIG.10 and FIG.11. FIG. 13 is a diagram showing a step after the step shown in FIG. 12. FIG. 14 is a diagram showing a step after the step shown in FIG. 13. FIG. 4 is a diagram showing a step after the step shown in FIG. 3. It is an electric circuit diagram of the nonreciprocal circuit device incorporating the magnetic rotor shown in FIGS.

Explanation of symbols

100 heat-resistant resin layer 200 polycarbonate polyurethane resin layer 301, 302 metal foil layer 32

Claims (6)

A heat resistant resin layer containing a polyamidoimide resin on one side of both sides of a polycarbonate polyurethane resin layer containing an isocyanurate compound as a curing agent, adjacent to the metal foil layer and not adjacent to the metal foil layer Are adjacent and the metal foil layer is patterned,
Flexible wiring board.   The flexible wiring board according to claim 1, wherein the polyamideimide resin has a glass transition temperature of 300 ° C. or higher.   The flexible wiring board according to claim 1 or 2, wherein the isocyanurate compound is mixed with the polycarbonate polyurethane resin in an amount of 5 to 30 wt%.   The flexible wiring board according to any one of claims 1 to 3, wherein 2 to 20 wt% of an epoxy resin is mixed with the polyamideimide resin. An electronic component including a flexible wiring board,
The flexible wiring board is the one described in any one of claims 1 to 4.
Electronic components.   6. The electronic component according to claim 5, wherein the electronic component is a non-reciprocal circuit element.

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