JP2006269948A - Insulating plate with peeling sheet and manufacturing method thereof - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide an insulating plate with a peeling sheet which can be easily and positively attached on a flexible circuit board even if it is made of a material susceptible to heat and pressure, can increase sticking strength on the flexible circuit board to prevent deviation, and facilitates transportation and sticking operation etc. thereof; and to provide a manufacturing method thereof. <P>SOLUTION: The insulating plate 1 with a peeling sheet is formed in such a way that an adhesive layer 30 containing at least a photo-curable resin is formed on the surface of a base material 10 consisting of a synthetic resin film. Further, a peeling sheet 50 is attached on the surface of the adhesive layer 30. To form the adhesive layer 30 on the surface of the base material 10, an adhesive in which a solvent is mixed into a resin material made of at least a photo-curing resin containing a thermosetting resin or a thermoplastic resin is applied to the surface of the base material 10, and then, the solvent is volatilized. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to an insulating plate with a release sheet suitable for use as a cover lay film or a reinforcing plate attached to a flexible circuit board, and a method for manufacturing the same.

  Conventionally, a flexible circuit board is generally covered with a cover lay film as an insulating plate on a circuit formed on the surface thereof. The reason why the coverlay film is provided is to prevent the circuit from coming into contact with other parts and short-circuiting. The cover lay film is configured by providing an adhesive layer on one surface of a base material made of an insulating synthetic resin film (for example, Patent Document 1). As the adhesive layer, an epoxy adhesive is generally used.

However, when the cover lay film is attached to the flexible circuit board by the adhesive layer made of the epoxy-based adhesive, the surface of the adhesive layer of the cover lay film is pressed against the flexible circuit board with a predetermined pressure (for example, 20 ˜30 kg / cm ² ), a predetermined high heat (for example, 150 ° C.) is applied for a predetermined time (for example, 1 hour). For this reason, a material that can withstand the heat and pressure for a long time must be selected as the flexible circuit board and the coverlay film. For example, an expensive polyimide film has to be used. On the other hand, for example, an inexpensive polyethylene terephthalate film (hereinafter referred to as “PET film”) may be deformed or deteriorated by the heat and pressure for a long time and cannot be used.

  On the other hand, some flexible circuit boards have a structure in which a lead-out portion is provided to connect to an electric circuit of another member. FIG. 7 is an enlarged perspective view of the main part showing the vicinity of the lead-out portion 550 and the connector 600 of this type of conventional flexible circuit board 500. As shown in the figure, a flexible circuit board 500 has a plurality of circuit patterns 520 formed in parallel on the upper surface of a base material 510 made of a thermoplastic synthetic resin film formed in a substantially band shape, and a contact pattern 521 at the end thereof. Cover the upper surface of the other parts except the part (this part is the lead-out part 550) with a cover lay film 530, and attach the reinforcing plate 540 to the back surface of the lead-out part 550 with a pressure-sensitive adhesive. Has been. The reason why the reinforcing plate 540 is affixed is that the lead-out portion 550 made of a synthetic resin film having flexibility is made rigid so that it can be easily and reliably inserted and connected to the connector 600 described below.

  On the other hand, the connector 600 is configured by housing and fixing a plurality of metal plate contact plates 620 in a rectangular synthetic resin case 610. Each contact plate 620 is installed at a position opposite to each contact pattern 521, and a substantially U-shaped contact portion 613 that sandwiches the lead-out portion 550 is provided on the opening 611 side provided on one side surface of the case 610. In addition, a connection portion 615 exposed from the case 610 to the outside is provided on the opposite side of each contact portion 613. Then, the lead-out portion 550 is inserted into the opening 611 of the connector 600, and the lead-out portion 550 is sandwiched between the contact portions 613 to press-connect the contact portions 613 and the contact pattern 521.

However, in the conventional lead-out portion 550, since the reinforcing plate 540 is pasted with a pressure-sensitive adhesive, the pasting strength is not necessarily strong, and the lead-out portion 550 is inserted into the connector 600. There is a possibility that the reinforcing plate 540 may be displaced from the lead-out portion 550 due to the strong clamping force applied. In the actual manufacture of the flexible circuit board 500, a plurality of circuits for the flexible circuit board 500 are formed on a single large synthetic resin film, and pressure sensitive adhesive is applied to the back surface side of each lead-out portion 550. A reinforcing plate 540 that is slightly larger than the regular dimension is attached with a material, and then the outer shape of each flexible circuit board 500 is punched out with a press die. At that time, the periphery of the reinforcing plate 540 is also cut into a regular dimension (final outer shape), but the pressure-sensitive adhesive material that bonds the reinforcing plate 540 has viscosity, and thus a press die was used. At that time, there is a risk that the pressure-sensitive adhesive material will adhere to the press die and gradually cut out the lead-out portion 550 with high accuracy. There was a risk that a separate process would be required to remove it.
JP 2004-315595 A

  The present invention has been made in view of the above-mentioned points, and the purpose thereof can be easily and reliably mounted on a flexible circuit board even if the insulating plate of the present invention is a base material that is weak against heat and pressure. The adhesive strength to the flexible circuit board can be increased to prevent deviation, etc., and even if it is cut using a press mold after being mounted on the flexible circuit board, the adhesive adheres to the press mold and has high accuracy. It is an object of the present invention to provide an insulating plate with a release sheet and a method for manufacturing the same without fear of being unable to cut, and further facilitating the conveyance and pasting work.

  The invention according to claim 1 of the present application is an insulating plate attached to a flexible circuit board, wherein the insulating plate forms an adhesive layer containing at least a photocurable resin on a surface of a base material made of a synthetic resin film, Further, the present invention is an insulating plate with a release sheet, characterized in that a release sheet is attached to the surface of the adhesive layer.

  The invention according to claim 2 of the present application is characterized in that the resin material constituting the adhesive layer includes at least a photocurable resin containing a thermosetting resin or a thermoplastic resin. It is in the insulating board with a peeling sheet as described in.

  Invention of Claim 3 of this application exists in the insulating board with a peeling sheet of Claim 1 or 2 whose said base material is a product made from a polyethylene terephthalate film.

  The invention according to claim 4 of the present application is a method for manufacturing an insulating plate attached to a flexible circuit board, wherein an adhesive layer containing at least a photo-curable resin is applied to the surface of a base material made of a synthetic resin film. And a step of affixing a release sheet to the surface of the adhesive layer, and a method of manufacturing an insulating plate with a release sheet.

  In the invention according to claim 5 of the present application, the adhesive layer is formed on the surface of the base material by adhering a solvent to a resin material containing at least a photocurable resin and a thermosetting resin or a thermoplastic resin. The method of manufacturing an insulating plate with a release sheet according to claim 4, wherein the solvent is volatilized after being applied onto the substrate.

  According to the first, second, and third aspects of the invention, since the release sheet is attached to the surface of the adhesive layer, it is not sticky and has good storage and transportability. Moreover, it can be easily attached to the flexible circuit board by simply peeling off the release sheet. In addition, since the adhesive layer is cured by light, it is not necessary to apply pressure simultaneously with heating for a long time when it is attached to a flexible circuit board. Therefore, the base material is weak against heating and pressurization such as PET film. Even if an inexpensive material is used, it can be easily and reliably mounted on the flexible circuit board. In addition, since the adhesive strength to the flexible circuit board can be increased as compared with the case where a pressure-sensitive adhesive is used as the adhesive layer, there is no deviation after the attachment to the flexible circuit board. Furthermore, the adhesive layer hardens reliably by light, so it is not sticky, and even if it is cut using a press die after being attached to a flexible circuit board, the adhesive adheres to the press die and cannot be cut accurately. There is no fear.

  According to the second aspect of the present invention, the adhesive layer is not pasty and can be made into a semi-cured state (cured state that is not too soft) that is not easily deformed by an external force. The release sheet can be easily attached to and detached from the surface, and can be easily attached to the flexible circuit board.

  According to invention of Claim 4, the insulating board with a peeling sheet of Claim 1 can be manufactured easily.

  According to the invention described in claim 5, the adhesive layer is not pasty and can be made into a semi-cured state (cured state that is not too soft) that is not easily deformed by an external force. The release sheet can be easily attached to and detached from the surface, and can be easily attached to the flexible circuit board.

  Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is an exploded perspective view of an insulating plate 1 with a release sheet according to an embodiment of the present invention, and FIG. 2 is a perspective view. As shown in FIG. 1, the insulating plate 1 with a release sheet forms an adhesive layer 30 containing at least a photocurable resin on the entire surface (the lower surface in FIG. 1) of a base material 10 made of a synthetic resin film. The release sheet 50 is attached to the surface of the adhesive layer 30 (the lower surface in FIG. 1). Hereinafter, each component of the insulating plate 1 with a release sheet will be described together with its manufacturing method.

  In order to manufacture the insulating plate 1 with the release sheet, first, the base material 10, the adhesive for forming the adhesive layer 30, and the release sheet 50 are prepared. The substrate 10 is made of a flexible insulating thermoplastic transparent or translucent (at least through UV rays) synthetic resin film (in this embodiment, a PET film having a thickness of 38 μm). The adhesive prepared for forming the adhesive layer 30 is configured by mixing a solvent with a resin material containing at least a photocurable resin and a thermosetting resin or a thermoplastic resin. As the photocurable resin, for example, an ultraviolet curable acrylate resin or the like is used. Examples of the acrylate resin include ester acrylate, urethane acrylate, epoxy acrylate, melamine acrylate, acrylic resin acrylate, and unsaturated polyester acrylate. Moreover, as a thermosetting resin or a thermoplastic resin mixed with the adhesive, for example, a polyester resin is used. Among polyester resins, there are thermosetting resins and thermoplastic resins. In addition, you may use the thing of other various materials as a photocurable resin, a thermosetting resin, and a thermoplastic resin. The solvent is used for dissolving a thermosetting resin or a thermoplastic resin mixed with the photocurable resin, for example, methyl ethyl ketone, butyl carbitol, butyl carbitol acetate, butyl cellosolve, ethyl carbitol, ethyl carbitol. It is composed of acetate or the like. The adhesive layer 30 formed of this adhesive is in a semi-cured state as described below, and at the same time has weak tackiness (adhesiveness). The thickness of the adhesive layer 30 is 35 to 50 μm in this embodiment. The release sheet 50 is made of an insulating synthetic resin film, paper, or the like, and has one surface (the surface facing the adhesive layer 30 side) having a smooth surface to facilitate peeling from the adhesive layer 30. The processing which becomes becomes.

  The adhesive layer 30 is formed on the surface of the base material 10 by applying the adhesive material to one surface (the lower surface in FIG. 1) of the base material 10 so as to form a uniform layer, and then the base material 10 as it is. Is heated at 70 ° C. to 80 ° C. to volatilize the solvent (the solvents to be volatilized are not necessarily all (100%), and may be in a desired ratio (for example, 80%)). The entire adhesive material including the thermosetting or thermoplastic resin component therein is not in the form of a paste, but the adhesive layer 30 is not easily deformed by an external force and is not easily deformed (cured state that is not too soft). The surface is weakly sticky (adhesive), and the adhesiveness between the adhesive layer 30 and the base material 10 is further enhanced by this semi-cured state as compared to the paste state. Further, the adhesive layer 30 will be described in detail. To form the adhesive layer 30, first, a photocurable resin and a thermoplastic resin (or thermosetting resin) are mixed and dispersed uniformly using a solvent. An adhesive for the liquid adhesive layer 30 is made. And this adhesive material is apply | coated to the base-material 10 surface. The solvent also has a function of uniformly applying the adhesive to the substrate 10. Next, the solvent is volatilized under the heating conditions, and a semi-cured adhesive layer 30 in which a liquid photocurable resin and a solid thermoplastic resin (or thermosetting resin) are mixed is formed. Adhesion with the base material 10 is performed between the thermoplastic resin (or thermosetting resin), and further, the adhesive layer 30 having a specified thickness is thereby obtained. Moreover, the weak adhesiveness of the adhesive material layer 30 surface is based on the liquid photocurable resin which is in the uncured state. Thereby, the optimal adhesive material layer 30 is completed as the adhesive material layer 30 of the base material 10 accompanied by the adhesive material layer 30 with the release sheet 50. The adhesive may be applied to the surface of the base material 10 by, for example, forming the adhesive material on the surface of the base material 10 so as to form a layer having a uniform predetermined thickness by a doctor blade method, or by printing means such as screen printing. It may be formed or applied by other methods. As described above, a material obtained by mixing a solvent with a resin material containing at least a photocurable resin and a thermosetting resin or a thermoplastic resin is suitable. Because in some conventional UV-curable resin materials, when applied to a base material, it is placed on the base material as a solid body having a certain stickiness, but in the form of a paste (decorative cream) Therefore, it is easily deformed and peeled off by external force. Therefore, if the release sheet 50 is pasted on the substrate 10 with a uniform thickness and then the release sheet 50 is pasted thereon, the uniformity of the adhesive layer cannot be maintained only by the pasting operation. Some are inappropriate to put or remove. Therefore, as described above, the adhesive that can be in the semi-cured state is used as the optimum adhesive for use in the adhesive layer 30 using the photocurable resin. In the present invention, it is not always necessary to mix a thermosetting resin or a thermoplastic resin, and at least a resin material containing a photocurable resin (only a photocurable resin may be used, or a thermosetting resin or a heat It may be in a semi-cured state, that is, a paste that is not easily deformed by an external force and has a weak adhesiveness (adhesiveness) on its surface. If it is made of a material that can be used, it may be used as an adhesive.

  As described above, since the adhesive layer 30 is in a semi-cured state, the adhesive layer 30 is not destroyed even if the release sheet 50 is attached to or peeled off from the surface of the adhesive layer 30. The adhesive layer 30 may be formed in multiple layers by forming and semi-curing the adhesive layer 30 a plurality of times. Further, the photocurable resin mixed with the adhesive may be various photocurable resins other than the ultraviolet curable resin.

  And if the said peeling sheet 50 is affixed on the surface of this adhesive material layer 30, the insulating board 1 with a peeling sheet will be completed. The adhesive layer 30 can be easily made into a semi-cured state as described above. Therefore, the adhesive layer 30 can be easily maintained in a state where the adhesive layer 30 is not broken. Therefore, the release sheet 50 can be easily attached to the surface. Alternatively, it can be easily attached to the flexible circuit board 70 described below. In addition, the production of the insulating sheet 1 with a release sheet, specifically, the adhesive layer 30 is continuously formed on the surface of the base material 10 drawn from the roll by using a doctor blade method or the like, Next, it is preferable to heat this to volatilize the solvent, and then to continuously apply the release sheet 50 drawn from another roll onto the adhesive layer 30. As described above, the insulating sheet 1 with a release sheet can be easily manufactured.

  As described above, the insulating plate 1 with a release sheet according to the present embodiment forms the adhesive layer 30 containing at least a photocurable resin on the surface of the base material 10 made of a synthetic resin film, and further this adhesive layer 30. The release sheet 50 is attached to the surface. Moreover, the manufacturing method of the insulation board 1 with a peeling sheet concerning this embodiment is the process of forming the adhesive material layer 30 by apply | coating the adhesive material containing at least photocurable resin to the surface of the base material 10 which consists of a synthetic resin film. And a step of attaching the release sheet 50 to the surface of the adhesive layer 30. Furthermore, the adhesive layer 30 is formed on the surface of the base material 10 by using an adhesive obtained by mixing a solvent with a resin material containing at least a photo-curable resin or a thermosetting resin or a thermoplastic resin on the base material 10. It is performed by volatilizing the solvent after coating.

  Next, an example of a method for using the insulating sheet 1 with the release sheet will be described. 3 to 5 show circuits with lead-out portions in which two types of insulating plates 1-1 and 1-2 with release sheets are attached to a flexible circuit board 70, and a cover lay film and a reinforcing plate are attached to the upper and lower surfaces, respectively. FIG. 3 is a diagram illustrating a method for manufacturing a substrate 100. Here, one insulating plate 1-1 with a release sheet is a cover lay film that covers and protects the upper surface of the circuit provided on the surface of the flexible circuit board 70, and the other insulating plate 1-2 with a release sheet is flexible. The reinforcing plate is attached to the back surface of the portion that becomes the lead-out portion 85 (see FIG. 6) of the circuit board 70 and reinforces it. First, as shown in FIG. 3, two types of insulating plates 1-1 and 1-2 with release sheets and a flexible circuit board 70 are prepared. As described above, the insulating sheet 1-1 with the release sheet is a cover lay film, and the base material 10 has a thickness of 38 μm and the adhesive layer 30 has a thickness of 35-50 μm. As described above, the insulating plate 1-2 with the release sheet serves as a reinforcing plate, and the thickness of the base 10 is 188 μm (the thickness is made thicker than the base 10 of the insulating plate 1-1 with the release sheet). The thickness of the adhesive layer 30 is 35 to 50 μm. Since both the flexible circuit board 70 and the insulating plates 1-1 and 1-2 with the release sheet are cut into a final outer shape, they are formed larger than the final outer shape. The difference between the insulating sheet 1-1 with the release sheet and the insulating plate 1-2 with the release sheet is only the thickness of the base material 10, the material of the base material 10 is the same, and the adhesive layer 30 and the release sheet 50 are The exact same thing is used. That is, the base material 10, the adhesive layer 30, and the release sheet 50 are each composed of the same composition. Therefore, although it is two types, the manufacturing process can be simplified. In some cases, if the thicknesses of the two base materials 10 are the same, it is possible to further reduce manufacturing costs, material costs, and the like. Of course, different materials and / or thicknesses may be used as the members constituting the two types of insulating plates 1-1 and 1-2 with release sheets.

  The flexible circuit board 70 forms a desired circuit 90 on an insulating substrate 80 made of a thermoplastic synthetic resin film having flexibility (in this embodiment, a PET film having a thickness of 50 μm to 75 μm), and a fixed resistance pattern. 93 and various electronic parts 95 and 97 are mounted. Although the circuit 90 is actually formed for wiring on a portion where the fixed resistance pattern 93 and various electronic components 95 and 97 are mounted, the description thereof is omitted for the sake of illustration. In this flexible circuit board 70, the entire portion of the flexible circuit board 70, which is provided with functional parts other than wiring, such as a circuit 90 for wiring and a fixed resistance pattern 93 and various electronic components 95 and 97, is referred to as a functional circuit board part 81. A portion provided with only the circuit 90 shown for wiring to draw out the lead-out portion 85 (see FIG. 6) is referred to as a wiring circuit board portion (hereinafter referred to as “drawing portion” in this embodiment) 83. The circuit 90 is made of conductive paste (for example, silver paste [a urethane-based or phenol-based resin material dissolved in a solvent and silver powder kneaded in a solvent)] or carbon paste [a urethane-based resin dissolved in a solvent or a phenol-based resin material such as carbon powder. And the like] are printed on the substrate 80 by screen printing or the like and heated at a predetermined temperature for a predetermined time. Needless to say, the circuit 90 may be formed by various printing methods other than screen printing or various pattern forming methods other than printing such as copper foil etching. The thickness of the circuit 90 is about 10 μm, for example. The electronic component 95 used in this embodiment is a chip-type fixed resistor, and the electronic component 97 is a chip-type light emitting diode (LED). Of course, other various electronic components (for example, a chip-type capacitor) may be used as the electronic components 95 and 97, and a pressure switch including a switch pattern on the substrate 80 and a dome-shaped movable contact plate installed thereon. Alternatively, a pattern for a membrane switch or a pattern for other functions may be provided.

Then, the release sheet 50 is peeled off from the insulating sheet 1-1 with the release sheet, and the surface of the adhesive layer 30 exposed as shown in FIG. 4 is the side on which the circuit 90 of the flexible circuit board 70 and various electronic components 95, 97 are provided. Paste on the surface. In addition, what peeled the peeling sheet 50 from the insulating board 1-1 with a peeling sheet is called insulating board 1-1a. At this time, the insulating plate 1-1a covers the flexible circuit board 70 including all the circuits 90 except for a portion (a tip portion of the circuit 90 shown in the figure) to be a contact pattern 87 described below having a function of connecting to another circuit. Is stuck on. Then, through the base material 10 from the outer surface side of the transparent base material 10 (on the side opposite to the surface on which the adhesive material layer 30 is provided), the adhesive material layer 30 is irradiated with ultraviolet rays of [1500 mJ / cm ² ] as an integrated light quantity. Thus, the adhesive layer 30 is completely cured, and the insulating plate 1-1a is fixed onto the flexible circuit board 70. At this time, the temperature is raised to about 90 ° C. As a result, the entire upper surface of the circuit 90 and the various electronic components 95 and 97 provided on the flexible circuit board 70 is covered with the insulating plate 1-1a. It is possible to reliably prevent the danger of Further, since the bonding between the insulating plate 1-1a and the flexible circuit board 70 is low at a temperature rise of about 90 ° C. and is not pressurized with a high pressure, the base material 10 constituting the insulating plate 1-1a and the insulating plate 1 As the flexible circuit board 70 to be attached with 1a, an inexpensive synthetic resin film (PET film in this embodiment) that is inferior in heat resistance can be used.

Next, the release sheet 50 is peeled off from the insulating sheet 1-2 with the release sheet having a size larger than the final shape of the lead-out portion 85 of the flexible circuit board 70, and the exposed surface of the adhesive layer 30 is shown in FIG. Affixed to the back surface of the portion of the flexible circuit board 70 where the contact pattern 87 is provided (the surface opposite to the surface where the circuit 90 is provided). In addition, what peeled the peeling sheet 50 from the insulating plate 1-2 with a peeling sheet is called insulating board 1-2a. Then, through the base material 10 from the outer surface side of the transparent base material 10 (on the side opposite to the surface on which the adhesive material layer 30 is provided), the adhesive material layer 30 is irradiated with ultraviolet rays of [1500 mJ / cm ² ] as an integrated light quantity. Thus, the adhesive layer 30 is completely cured, and the insulating plate 1-2a is fixed to the flexible circuit board 70. At this time, the temperature is raised to about 90 ° C. Alternatively, the insulating plates 1-1a and 1-2a may be attached to the upper and lower surfaces of the flexible circuit board 70, and both may be simultaneously fixed to the flexible circuit board 70 by irradiating ultraviolet rays. The reason why ultraviolet rays were irradiated toward the adhesive layer 30 from the side opposite to the surface on which the adhesive layer 30 was provided on each of the insulating plates 1-1a and 1-2a is that the entire surface was irradiated with ultraviolet rays from the transparent substrate 10 side. By irradiating, the entire adhesive layer 30 is surely irradiated with ultraviolet rays to be cured uniformly.

  Finally, when the outer shape of the flexible circuit board 70 to which the insulating plates 1-1a and 1-2a are attached is punched out by a press die, the circuit board 100 with a lead-out portion shown in FIG. 6 is completed. As described above, the completed circuit board 100 with the lead-out portion includes the functional circuit board portion 81 and the lead-out portion 83, and the upper surfaces thereof are covered with the base material 10 of the insulating plate 1-1a as a cover lay film. In addition, a contact pattern 87 composed of exposed ends of a plurality of circuits 90 that are not covered by the base material 10 is provided at the leading end of the lead portion 83, and an insulating plate as a reinforcing plate is provided on the back surface of the contact pattern 87. The base 10 of 1-2a will be affixed. The portion provided with the contact pattern 87 becomes a lead-out portion 85 having a final outer shape.

  As described above, according to the insulating sheet with release sheet 1 (1-1, 1-2) according to the present invention, the release sheet 50 is attached to the surface of the adhesive layer 30, so that it is not sticky and its storability. And good transportability. Moreover, it can be easily attached to the flexible circuit board 70 by simply peeling off the release sheet 50. Further, since the adhesive layer 30 is cured by light (ultraviolet rays in this embodiment), it is not necessary to apply pressure to the flexible circuit board 70 simultaneously with heating for a long time. As the flexible circuit board 70 to which the insulating plate with sheet 1 (1-1, 1-2) is attached, an inexpensive material such as a PET film that is weak against heating and pressurization can be used. Further, the adhesive layer 30 is reliably cured by ultraviolet rays and has a strong adhesive strength, and the adhesive strength to the flexible circuit board 70 can be increased as compared with the case where a pressure-sensitive adhesive is used as the adhesive layer 30. There will be no misalignment after attachment to 70. Therefore, especially when this insulating sheet with release sheet 1-2 is used as a reinforcing plate for the lead-out portion 85, even when a strong clamping force is applied when the lead-out portion 85 is attached to or detached from the connector 600 as shown in FIG. The insulating plate 1-2a is not likely to be displaced from the flexible circuit board 70. Further, when the insulating plate 1-1a and / or 1-2a is attached to the surface of the flexible circuit board 70 having a large size as described above, and then the regular outer shape of the flexible circuit board 70 is punched by a press die, Although the periphery of the insulating plate 1-1a and / or 1-2a is also cut to a regular dimension, the adhesive layer 30 is securely cured and has no viscosity, so that the adhesive adheres to the press mold. Therefore, the press mold can always perform cutting with high accuracy at the same time, and at the same time, a process of removing the adhered adhesive from the press mold is not necessary. Further, since the adhesive layer 30 is not provided for ensuring insulation, the adhesive layer 30 does not need to be thickly coated and can be easily provided with flexibility, and at the same time, the substrate 10 can be provided with flexibility. Therefore, the flexibility of the flexible substrate 70 to which the substrate is attached is not impaired (of course, when used as a reinforcing plate, the rigidity of the substrate 10 may be increased by increasing the thickness of the substrate 10 as in the above embodiment).

  Although the embodiments of the present invention have been described above, the present invention is not limited to the above-described embodiments, and various modifications can be made within the scope of the technical idea described in the claims and the specification and drawings. Is possible. It should be noted that any shape, structure, and material not directly described in the specification and drawings are within the scope of the technical idea of the present invention as long as the effects and advantages of the present invention are exhibited. For example, although the PET film is used as the base material 10 in the above embodiment, synthetic resin films made of various other materials may be used. Various changes can be made in the same manner with respect to the other materials constituting the embodiment. In addition, as a method of using the insulating plate 1 with the release sheet, the method of attaching the insulating plates 1-1a and 1-2a to both surfaces of the flexible circuit board 70 has been described, but it goes without saying that it may be attached to only one surface. Moreover, in the usage method of the said insulating board 1 with a peeling sheet, although the insulating board 1 with a peeling sheet was utilized as a cover-lay film and a reinforcement board of the flexible circuit board 70, you may use it for purposes other than those. Moreover, in the said embodiment, although insulating board 1-1a used as a cover lay film was fixed to flexible circuit board 70, insulating board 1-2a used as a reinforcing board was fixed, but this order was changed and performed in the reverse order. Also good.

It is a disassembled perspective view of the insulating board with a peeling sheet. It is a perspective view of the insulating board 1 with a peeling sheet. It is a figure which shows the method of attaching the insulating plates 1-1 and 1-2 with a peeling sheet to the flexible circuit board. It is a figure which shows the method of attaching the insulating plates 1-1 and 1-2 with a peeling sheet to the flexible circuit board. It is a figure which shows the method of attaching the insulating plates 1-1 and 1-2 with a peeling sheet to the flexible circuit board. It is a perspective view which shows the circuit board 100 with a lead-out part. It is a principal part expansion perspective view which shows the lead-out part 550 vicinity part and connector 600 of the conventional flexible circuit board 500. FIG.

Explanation of symbols

1 (1-1, 1-2) Insulating plate with release sheet 1-1a, 1-2a Insulating plate 10 Base material 30 Adhesive layer 50 Release sheet 70 Flexible circuit board 80 Substrate 85 Lead-out unit 90 Circuit

Claims (5)

In the insulating plate attached to the flexible circuit board,
The insulating plate is formed by forming an adhesive layer containing at least a photocurable resin on the surface of a base material made of a synthetic resin film, and further attaching a release sheet to the surface of the adhesive layer. An insulating plate with a release sheet.   2. The insulating sheet with a release sheet according to claim 1, wherein the resin material constituting the adhesive layer includes at least a photocurable resin containing a thermosetting resin or a thermoplastic resin.   The insulating substrate with a release sheet according to claim 1 or 2, wherein the substrate is made of polyethylene terephthalate film. In the method of manufacturing an insulating plate attached to a flexible circuit board,
Forming an adhesive layer by applying an adhesive containing at least a photocurable resin to the surface of a base material made of a synthetic resin film;
And a step of attaching a release sheet to the surface of the adhesive layer. A method for producing an insulating plate with a release sheet.   Formation of the adhesive layer on the surface of the base material is performed by applying an adhesive material obtained by mixing a solvent to a resin material containing at least a photocurable resin to a thermosetting resin or a thermoplastic resin on the base material. The method for producing an insulating plate with a release sheet according to claim 4, wherein the method is performed by volatilizing the solvent.

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