JP2004172525A - Manufacturing method, and manufacturing apparatus with flexible wiring board - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a method for manufacturing a flexible wiring board in which insulation and reliability of a circuit is improved, controllability, workability and resource saving in heating are improved and warping does not occur, and to provide an apparatus for manufacturing the flexible wiring board for realizing the manufacturing method. <P>SOLUTION: The manufacture of the flexible wiring board is provided with an application step of forming a solder resist layer in a predetermined shape on an upper surface of the board, and a heating and hardening step of taking up the board on which the solder resist layer is formed in the form of roll via a protecting tape around a reel having protecting plates on its both lateral sides, drying and hardening the solder resist layer by inductively heating the protecting plates by means of a heating and hardening part having one or more magnetic field generating coils disposed at intervals on at least one of outer surfaces of the protecting plates while rotating the reel through a rotary mechanism. <P>COPYRIGHT: (C)2004,JPO

Description

[0001]
TECHNICAL FIELD OF THE INVENTION
The present invention relates to a method for manufacturing a flexible wiring board used for a semiconductor packaging such as an IC card terminal, a high-density wiring board incorporated in an electronic device such as a portable information terminal, and a flexible wiring board manufacturing apparatus using the manufacturing method. It is about.
[0002]
[Prior art]
The flexible wiring board uses a material such as a resin tape, which has excellent curability and can be made thinner, for the substrate, so that high-density wiring to be incorporated in semiconductor devices such as IC card terminals and electronic devices such as portable information terminals. It is used for boards and the like.
[0003]
Hereinafter, a conventional method for manufacturing a flexible wiring board will be described with reference to the drawings.
[0004]
17 is a cross-sectional view of a main part of a step of forming a circuit pattern electrode on a substrate, FIG. 18 is a cross-sectional view of a main part of a substrate on which a circuit pattern electrode is formed, and FIG. FIG. 20 is a partial cross-sectional view, FIG. 20 is a main-portion cross-sectional view of the substrate on which the solder resist layer is formed, and FIG. 21 is a perspective view of a reel in a process of winding the substrate on which the solder resist layer is formed. FIG. 23 is a perspective view of a step of drying and curing in a hot air drying furnace, and FIG. 23 is an enlarged view of a portion I in FIG. 17 to 23, reference numeral 38 denotes a substrate made of a resin tape of polyimide or epoxy, etc., 39 denotes a metal foil bonded to the surface of the substrate 38 and made of copper or the like, and 40 denotes a photolithography method on the upper surface of the metal foil 39. And an etching resist layer 41 corresponding to a negative shape of a circuit pattern described later, and an unnecessary portion of the metal foil 39 not covered with the etching resist layer 40 is etched with an etching solution such as an aqueous ferric chloride solution. A circuit pattern formed by dissolving and removing; 42, a screen plate made on the upper surface of the substrate 38 holding the circuit pattern 41; 43, a solder resist layer formed on the upper surface of the substrate 38 holding the circuit pattern 41; 44 is a flexible wiring board on which a solder resist layer 43 is formed; 45 is a protective tape made of an embossed tape or the like; Is a reel on which the flexible wiring board 44 holding the solder resist layer 43 on the surface and the protective tape 45 are wound, and 47 is a hot air blower. The reel 46 is put in the room and the solder resist layer 43 on the surface of the flexible wiring board 44 is placed. Is a hot air drying oven for drying and curing, and 48 is a warm air heater using electricity or gas.
[0005]
A method of manufacturing the conventional flexible wiring board configured as described above will be described below. As shown in FIG. 17, a metal foil 39 is bonded to the surface of the substrate. Next, an etching resist layer 40 corresponding to the negative shape of the circuit pattern 41 is provided on the upper surface of the metal foil 39 by photolithography or printing. Next, after dissolving and removing unnecessary portions of the metal foil 39 which are not covered with the etching resist layer 40 with an etching solution, the etching resist layer 40 is removed from the substrate 38 as shown in FIG. A circuit pattern 41 is formed on the surface. Next, as shown in FIG. 19, an inner lead connected to a semiconductor such as an IC, an outer lead connected to a liquid crystal display element, and a lead portion connected to a passive element are formed on an upper surface of a substrate 38 holding a circuit pattern 41. Is covered with a screen plate 42 that hides the screen. Next, a solder resist layer 43 is formed by applying an insulating ink from above the screen plate 42 by a screen printing method or the like, and by removing the screen plate 42, a solder resist layer is formed on the surface as shown in FIG. A flexible wiring board 44 holding the layer 43 is formed. Next, as shown in FIG. 21, a protective tape 45 is laminated on the upper surface of the flexible wiring board 44 holding the solder resist layer 43 on the surface, and sent to the reel 46 to reduce the length of the flexible wiring board 44 from 10 m to 100 m. It is wound and wound on one reel. After the winding, the reel 46 is put into a hot-air drying furnace 47, and the solder resist layer 43 is dried and cured by the hot air blower 48 at a temperature of 120 ° C. to 180 ° C. in accordance with the drying and curing temperature conditions of the insulating ink.
[0006]
In accordance with the recent trend toward smaller and lighter electronic devices, circuit wiring patterns have been miniaturized, and as a result, the insulation, heat resistance, chemical resistance, etc. of circuit wiring and adjacent leads, which are the roles of solder resist layers, have been improved. Have come to demand higher levels. In order to satisfy this requirement, the insulating ink of the wiring board is a thermosetting resin such as an epoxy-based or polyimide-based resin, but since a polyimide resin is often used as a substrate particularly in a flexible wiring board, A polyimide-based resin or a mixture of a polyimide-based resin and an epoxy-based resin as a curing agent using γ-butyrolactone or triethylene glycol dimethyl ether as a solvent has been used.
[0007]
However, since the solder resist layer is dried at a high temperature, there is a problem that bubbles are generated by vaporization of the solvent from the solder resist layer. In addition, as shown in FIG. 23, the viscosity is lowered due to the high temperature and the desired pattern shape of the solder resist layer is broken, so that a part of the solder resist layer flows into the lead portion of the circuit pattern, and the insulation of the lead portion and the outer process in a later process are performed. There is also a problem that the reliability of lead wire bonding is reduced.
[0008]
In order to solve these problems, in the conventional method of manufacturing a flexible wiring board, a method of applying an insulating ink to a substrate, and then raising the temperature in four steps with hot air and far-infrared rays to cure the substrate is proposed. (See Patent Document 1).
[0009]
[Patent Document 1]
JP-A-11-238743
[0010]
[Problems to be solved by the invention]
However, the above conventional technology has the following problems.
[0011]
The technology disclosed in Japanese Patent Application Laid-Open No. H11-157572 has a problem that curing is required in a step different from the application step of the insulating ink, and a problem that it takes a long time to cure by increasing the temperature in four steps. And a problem that equipment for drying and curing becomes large.
[0012]
The present invention solves the above-mentioned conventional problems, and can heat-dry and cure a solder resist layer at a uniform temperature efficiently and in a short time without collapsing the pattern shape, thereby improving the insulation and reliability of the circuit. An object of the present invention is to provide a method for manufacturing a flexible wiring board which is excellent in heat controllability and workability during heating and resource saving, and does not generate warpage, and to provide a flexible wiring board manufacturing apparatus which realizes the manufacturing method. Aim.
[0013]
[Means for Solving the Problems]
In order to solve the above conventional problems, a method for manufacturing a flexible wiring board according to the present invention comprises the steps of: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on its surface to form a solder resist layer in a predetermined shape; b. The substrate on which the solder resist layer is formed is wound into a roll via a protective tape on a reel having protective plates on both sides, and the reel is rotated by a rotating mechanism, and a gap is provided on at least one of the outer surfaces of the protective plate. A heating and curing step of drying and curing the solder resist layer by inductively heating the protective plate by a heating and curing unit having one or more magnetic field generating coils arranged apart.
[0014]
With this configuration, the solder resist layer can be heated, dried and cured efficiently at a uniform temperature in a short time, and a method of manufacturing a flexible wiring board excellent in controllability during heating and resource saving can be obtained.
[0015]
In order to solve the above conventional problems, a method for manufacturing a flexible wiring board according to the present invention comprises the steps of: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on its surface to form a solder resist layer in a predetermined shape; b. Immediately after the coating step, in a heating and drying unit having a heating element and a heating medium in contact with the substrate, heat generated from the heating element is transmitted to the heating medium, and the surface temperature (Ts) of the substrate is reduced to 70 ° C. <Ts. A heating and drying step of drying the surface of the solder resist layer by contacting with a heating medium at <120 ° C .; c. The substrate on which the solder resist layer is formed is wound into a roll via a protective tape on a reel having protective plates on both sides, and the reel is rotated by a rotating mechanism, and a gap is provided on at least one of the outer surfaces of the protective plate. And a heat curing step of curing the solder resist layer by inductively heating the protective plate with a heat curing unit having one or more magnetic field generating coils arranged apart.
[0016]
With this configuration, the solder resist layer can be heated, dried and cured efficiently and at a uniform temperature in a short time without disturbing the pattern shape, resulting in excellent circuit insulation and reliability, controllability and workability during heating. In addition, a method for manufacturing a flexible wiring board which is excellent in resource saving and does not warp can be obtained.
[0017]
The apparatus for manufacturing a flexible wiring board according to the present invention includes: a. A substrate supply reel for delivering a substrate having a circuit pattern formed on a surface thereof; b. A transport unit for transporting the substrate delivered from the substrate supply reel on the upper surface; c. An application unit that is provided downstream in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape; d. A protection tape supply reel that is provided downstream from the coating unit in the transport direction of the transport unit and that delivers a protective tape laminated on the upper surface of the substrate; e. A reel that is provided downstream from the protective tape supply reel in the transport direction of the transport unit and has a protective plate on both sides, and a substrate on which the solder resist layer is formed is wound into a roll via a protective tape, f. Heating that embeds inside the protective plate or has at least one heating element arranged at least on the outer surface side of the protective plate with a space between them, and heats the protective plate to dry and cure the solder resist layer. And a hardening part.
[0018]
With this configuration, the solder resist layer can be heated, dried and cured efficiently at a uniform temperature in a short time, and a flexible wiring board manufacturing apparatus excellent in controllability during heating and resource saving can be obtained.
[0019]
BEST MODE FOR CARRYING OUT THE INVENTION
The method for producing a flexible wiring board according to claim 1 of the present invention comprises the steps of: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on its surface to form a solder resist layer in a predetermined shape; b. The substrate on which the solder resist layer is formed is wound into a roll via a protective tape on a reel having a protective plate on both sides, and is buried inside the protective plate or is provided at least on one of the outer surface sides of the protective plate. And a heat-curing step of drying and curing the solder resist layer by heating the protective plate with a heat-curing unit having one or more heating elements arranged with a space therebetween.
[0020]
With this configuration, the following operation is obtained.
[0021]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0022]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0023]
Here, as the substrate, a polyimide-based or epoxy-based insulating resin or the like is used. In particular, polyimide-based resins have high flexibility, can be made thinner, have a high melting point and softening point, have high mechanical strength even at high temperatures, are unlikely to undergo thermal decomposition and thermal degradation, and are resistant to oxygen and chemicals. It is preferably used because it is excellent.
[0024]
The thickness of the substrate is preferably 25 to 100 μm. When the thickness is smaller than 25 μm, warpage tends to occur during drying and curing, and when the thickness is larger than 100 μm, the substrate tends to be inferior in flexibility and tend to generate a temperature gradient in the substrate. .
[0025]
The circuit pattern is formed by adhering a metal foil such as aluminum or copper to the surface of the substrate, then arranging an etching resist layer on the required part by photolithography or printing, and removing unnecessary parts with an etchant. You. In particular, when the circuit pattern is made of copper, it is preferably used because it has excellent heat conduction and can conduct heat uniformly during heat curing.
[0026]
As the insulating ink, a polyimide-based resin using γ-butyrolactone or triethylene glycol dimethyl ether as a solvent, or a mixture of a polyimide-based resin and an epoxy-based resin as a curing agent can be used.
[0027]
As the protective plate, a metal plate such as aluminum or stainless steel, or a non-ferrous metal such as plastic is used. Particularly, aluminum is preferably used because it is excellent in heat conductivity and heat radiation and inexpensive. In the case of non-ferrous metals, the Joule heat generated before was about one-twentieth of that of iron, but recently, by increasing the frequency of the heating current and reducing the coil diameter, electromagnetic induction heating has been achieved. It is available for use.
[0028]
Further, as the shape of the protection plate, a single plate shape, a shape having a plurality of openings in one plate, a punching metal shape, a spoke shape, and the like are used. The insulating ink having a small amount of solvent may have a single-plate shape, but the one having a large amount of evaporation may have a shape having an opening for discharging the solvent vapor, that is, a shape having a plurality of openings in a single plate, and punching. It is preferable to use different shapes depending on the composition of the insulating ink, such as using a metal shape and a spoke shape.
[0029]
For the reel, a metal such as aluminum or iron, or a non-ferrous metal such as plastic is used, and it is preferable to use the same material as the protective plate. The reel is used for supplying and winding the substrate.
[0030]
As a material of the protective tape, polyimide, plastic, or the like is used. In particular, polyimide-based resins have high flexibility, can be made thinner, have a high melting point and softening point, have high mechanical strength even at high temperatures, are unlikely to undergo thermal decomposition and thermal degradation, and are resistant to oxygen and chemicals. It is preferably used because it is excellent.
[0031]
Further, the shape of the protective tape is required to have a shape having irregularities so as not to touch the solder resist layer. Therefore, an embossed tape that has a gap when laminated on the upper surface of the substrate and that can prevent contact with the back surface of the upper substrate on which the solder resist layer is laminated during winding is preferably used.
[0032]
For the heating element, a hot air heater, a sheath heater, a far-infrared radiator, a coil, etc. are used.For the method of heating and hardening using them, the hot air heater is arranged on the side of the protection plate and the hot air is Method of heating by applying heat, method of burying a sheathed heater inside the protective plate and heating the protective plate by the heater, method of arranging a far-infrared radiator around the reel, irradiating far-infrared rays to the protective plate, and heating Is disposed around the protection plate, and the protection plate is induction-heated by Joule heat of an eddy current generated by a magnetic field. In particular, the method of inductively heating the protective plate by Joule heat of eddy current generated by a magnetic field by arranging the coil around the protective plate has an excellent efficiency of converting electricity used into heat, and facilitates temperature control of the protective plate. Therefore, it is suitably used. Further, by evaporating the solvent component from the insulating ink heated by the heating element to crosslink the residual component, the performance such as chemical resistance of the solder resist layer is exhibited.
[0033]
As a method of disposing the heating element, a method of disposing the heating element on both sides on the outer surface side of the protection plate and a method of disposing the heating element on one side on the outer surface side of the protection plate are used. In particular, the method of disposing the protective plate on both sides on the outer surface side is suitably used because heat radiation is generated from both surfaces to make the temperature distribution uniform.
[0034]
Regarding the number of heating elements, a method of arranging one in the center, a method of arranging two diagonally, and a method of arranging four or more in a polygonal shape are used. In particular, a method of arranging four or more pieces in a polygonal shape is preferably used because heating unevenness can be reduced and a uniform temperature distribution can be obtained.
[0035]
The method for manufacturing a flexible wiring board according to claim 2 comprises the steps of: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on its surface to form a solder resist layer in a predetermined shape; b. The substrate on which the solder resist layer is formed is wound into a roll via a protective tape on a reel having protective plates on both sides, and the reel is rotated by a rotating mechanism, and a gap is provided on at least one of the outer surfaces of the protective plate. A heating and curing step of drying and curing the solder resist layer by inductively heating the protective plate by a heating and curing unit having one or more magnetic field generating coils arranged apart.
[0036]
With this configuration, the following operation is obtained.
[0037]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0038]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0039]
(3) Heating can be performed at a low temperature because it is heated, dried and cured while being wound.
[0040]
(4) The magnetic field generated by applying a high-frequency current to the magnetic field generating coil generates an eddy current on the surface of the protection plate, and the protection plate is heated using the induction heating in which the Joule heat of the generated eddy current generates heat. The temperature can be raised in a short time.
[0041]
(5) Since the heat value is proportional to the current value, the heat value can be quickly controlled by controlling the current value.
[0042]
(6) Since the portion to be heated by rotating the reel by the rotating mechanism can be dispersed, the temperature distribution of the protective plate can be made uniform.
[0043]
Here, as the rotating mechanism, one capable of controlling the speed by changing the speed based on the amounts of the substrate and the protective tape wound on the reel is suitably used.
[0044]
Copper, iron, and aluminum are used for the magnetic field generating coil. In particular, iron is preferably used because it has good magnetic force characteristics.
[0045]
As a method of arranging the magnetic field generating coil, a method of arranging it on both sides on the outer surface side of the protection plate and a method of arranging it on one side of the outer surface side of the protection plate are used. In particular, the method of disposing the protective plate on both sides on the outer surface side is suitably used because heat radiation is generated from both surfaces to make the temperature distribution uniform.
[0046]
Regarding the number of magnetic field generating coils, a method of arranging one in the center, a method of arranging two coils diagonally, and a method of arranging four or more coils in a polygonal shape are used. In particular, a method of arranging four or more pieces in a polygonal shape is preferably used because heating unevenness can be reduced and a uniform temperature distribution can be obtained.
[0047]
The wire diameter of the magnetic field generating coil is preferably 0.05 to 0.3 mm. As the wire diameter becomes smaller than 0.05 mm, the allowable current value tends to decrease, and as the wire diameter becomes larger than 0.3 mm, the magnetic field generating coil tends to increase in size.
[0048]
The frequency of the magnetic field generating coil is preferably 20 to 60 kHz. As the frequency is lower than 20 kHz, the temperature of the protective plate tends to take a longer time, and as the frequency is higher than 60 kHz, the size of the apparatus tends to be increased in order to generate a high frequency.
[0049]
The method for manufacturing a flexible wiring board according to claim 3 includes: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on its surface to form a solder resist layer in a predetermined shape; b. Immediately after the coating step, in a heating and drying unit having a heating element and a heating medium in contact with the substrate, the heat generated by the heating element is conducted to the heating medium, and the substrate is brought into contact with the heating medium, so that the surface of the solder resist layer is exposed. A heating and drying step for drying c. A heating and curing step of heating the substrate holding the surface-dried solder resist layer to a high temperature by a heating and curing unit to cure the solder resist layer.
[0050]
With this configuration, the following operation is obtained.
[0051]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0052]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0053]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0054]
Here, as the heating element, a heat exchanger such as a nichrome wire or hot water is used. Particularly, a nichrome wire is preferably used because it generates a large amount of heat.
[0055]
As the heat medium, aluminum, copper, stainless steel, or the like can be used, and aluminum is particularly preferable because it has excellent heat radiation characteristics.
[0056]
As a method of contacting the heat medium with the substrate, a method of making contact with the back surface of the substrate and a method of making contact with the surface of the substrate are used. In particular, the method of contacting with the back surface of the substrate is preferably used because it can be dried without directly touching the solder resist layer.
[0057]
The temperature in the heat curing step is preferably from 70 to 120C. As the temperature becomes lower than 70 ° C., it takes a long time for the solvent to evaporate from the insulating ink, and as the temperature becomes higher than 120 ° C., bubbles of the solvent are generated from the insulating ink, There is a tendency for the viscosity to decrease and the desired pattern shape to collapse, which is not preferred.
[0058]
The temperature in the heating and drying step is preferably from 120 to 180 ° C. As the temperature becomes lower than 120 ° C., it takes a long time to cure the insulating ink to form a solder resist layer, and as the temperature becomes higher than 180 ° C., the viscosity of the insulating ink decreases and the desired pattern shape is reduced. Tend to collapse, and both are not preferred.
[0059]
The method for manufacturing a flexible wiring board according to claim 4 includes: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on its surface to form a solder resist layer in a predetermined shape; b. Immediately after the coating step, in a heating and drying unit having a heating element and a heating medium in contact with the substrate, heat generated from the heating element is transmitted to the heating medium, and the substrate is brought into contact with the heating medium to form a solder resist layer. A heat drying step of drying the surface; c. On a reel having protective plates on both sides, a substrate holding the solder resist layer whose surface has been dried is wound up in a roll via a protective tape, and is buried inside the protective plate or at least one of the outer surfaces of the protective plate And a heat curing step of curing the solder resist layer by heating the protective plate with a heat curing unit having one or more heating elements arranged at intervals.
[0060]
With this configuration, the following operation is obtained.
[0061]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0062]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0063]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0064]
(4) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0065]
(5) Since the operations of winding and heat drying and curing can be performed at the same time, heat curing can be performed efficiently in a short time.
[0066]
The method for manufacturing a flexible wiring board according to claim 5 includes: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on its surface to form a solder resist layer in a predetermined shape; b. Immediately after the coating step, in a heating and drying unit having a heating element and a heating medium in contact with the substrate, the heat generated by the heating element is conducted to the heating medium, and the substrate is brought into contact with the heating medium, so that the surface of the solder resist layer is exposed. A heating and drying step for drying c. The substrate on which the solder resist layer is formed is wound into a roll via a protective tape on a reel having protective plates on both sides, and the reel is rotated by a rotating mechanism, and a gap is provided on at least one of the outer surfaces of the protective plate. And a heat curing step of curing the solder resist layer by inductively heating the protective plate with a heat curing unit having one or more magnetic field generating coils arranged apart.
[0067]
With this configuration, the following operation is obtained.
[0068]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0069]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0070]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0071]
(4) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat conduction from the protective plate, it is possible to efficiently heat and dry and cure.
[0072]
(5) Since the operations of winding and heat drying and curing can be performed at the same time, heat curing can be performed efficiently in a short time.
[0073]
(6) Heating can be performed at a low temperature because it is heated, dried and cured while being wound.
[0074]
(7) The magnetic field generated by applying a high-frequency current to the magnetic field generating coil generates an eddy current on the surface of the protective plate, and the protective plate is heated using the induction heating in which the Joule heat of the generated eddy current generates heat. The temperature can be raised in a short time.
[0075]
(8) Since the heat value is proportional to the current value, the heat value can be quickly controlled by controlling the current value.
[0076]
(9) Since the portion to be heated by rotating the reel by the rotation mechanism can be dispersed, the temperature distribution of the protective plate can be made uniform.
[0077]
The method of manufacturing a flexible wiring board according to claim 6 is the method of manufacturing a flexible wiring board according to any one of claims 3 to 5, wherein the surface temperature (Ts) ) Is 70 ° C. <Ts <120 ° C.
[0078]
With this configuration, the following operation is obtained in addition to the operation described in any one of the third to fifth aspects.
[0079]
(1) Since bubbles can be prevented from being generated due to vaporization of the solvent from the solder resist layer, and the surface drying of the solder resist layer can be improved, the circuit is excellent in reliability and insulation.
[0080]
Here, depending on the amount and viscosity of the solvent of the insulating ink, it is better to keep the substrate in a horizontal state and dry it before drying and curing while winding up, so that the shape of the solder resist layer can be maintained. This is remarkable when an ink having a solvent content of more than 50% or an insulating ink having an ink viscosity of 100 Pa · s or less at 20 ° C. is used.
[0081]
An apparatus for manufacturing a flexible wiring board according to claim 7 is an apparatus for realizing the method for manufacturing a flexible wiring board according to claim 1, comprising: a. A substrate supply reel for delivering a substrate having a circuit pattern formed on a surface thereof; b. A transport unit for transporting the substrate delivered from the substrate supply reel on the upper surface; c. An application unit that is provided downstream in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape; d. A protection tape supply reel that is provided downstream from the coating unit in the transport direction of the transport unit and that delivers a protective tape laminated on the upper surface of the substrate; e. A reel that is provided downstream from the protective tape supply reel in the transport direction of the transport unit and has a protective plate on both sides, and a substrate on which the solder resist layer is formed is wound into a roll via a protective tape, f. Heating that embeds inside the protective plate or has at least one heating element arranged at least on the outer surface side of the protective plate with a space between them, and heats the protective plate to dry and cure the solder resist layer. And a hardening part.
[0082]
With this configuration, the following operation is obtained.
[0083]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0084]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0085]
Here, a metal such as aluminum or iron is used for the substrate supply reel. In particular, aluminum is preferably used because of its light weight and excellent strength.
[0086]
For the transport unit, a belt conveyor, a group of rollers, and the like are used. In particular, a belt conveyor is suitably used because it can stably convey.
[0087]
As a coating method, a screen printing method, an electroforming method, a photolithography method, or the like is used. In particular, the screen printing method is preferably used because the same pattern can be repeatedly printed in a short time and accurately.
[0088]
For the protective tape supply reel, metal such as aluminum or iron, plastic, or the like is used. In particular, aluminum is preferably used because of its light weight and excellent workability during transportation.
[0089]
As the protective plate, a metal plate such as aluminum or stainless steel, or a non-ferrous metal such as plastic is used. Particularly, aluminum is preferably used because it is excellent in heat conductivity and heat radiation and inexpensive. In the case of non-ferrous metals, Joule heat was about one-twentieth of that of iron before, but it can be used by increasing the frequency of the heating current and making the coil diameter smaller. .
[0090]
Further, as the shape of the protection plate, a single plate shape, a shape having a plurality of openings in one plate, a punching metal shape, a spoke shape, and the like are used. The insulating ink having a small amount of solvent may have a single-plate shape, but the one having a large amount of evaporation may have a shape having an opening for discharging the solvent vapor, that is, a shape having a plurality of openings in a single plate, and punching. It is preferable to use different shapes depending on the composition of the insulating ink, such as using a metal shape and a spoke shape.
[0091]
For the reel, a metal such as aluminum or iron, or a non-ferrous metal such as plastic is used, and it is preferable to use the same material as the protective plate. The reel is used for supplying and winding the substrate.
[0092]
An apparatus for manufacturing a flexible wiring board according to claim 8 is an apparatus for realizing the method for manufacturing a flexible wiring board according to claim 2, comprising: a. A substrate supply reel for delivering a substrate having a circuit pattern formed on a surface thereof; b. A transport unit for transporting the substrate delivered from the substrate supply reel on the upper surface; c. An application unit that is provided downstream in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape; d. A protection tape supply reel that is provided downstream from the coating unit in the transport direction of the transport unit and that delivers a protective tape laminated on the upper surface of the substrate; e. A reel that is provided downstream from the protective tape supply reel in the transport direction of the transport unit and has a protective plate on both sides, and a substrate on which the solder resist layer is formed is wound into a roll via a protective tape, f. A rotating mechanism disposed at both ends of the reel for rotating the reel; g. A heat-curing section having at least one magnetic field generating coil disposed at least on one of the outer surface sides of the protective plate with a space therebetween and inductively heating the protective plate with a magnetic field generated by the magnetic field generating coil; have.
[0093]
With this configuration, the following operation is obtained.
[0094]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0095]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0096]
(3) Heating can be performed at a low temperature because it is heated, dried and cured while being wound.
[0097]
(4) The magnetic field generated by applying a high-frequency current to the magnetic field generating coil generates an eddy current on the surface of the protection plate, and the protection plate is heated using the induction heating in which the Joule heat of the generated eddy current generates heat. The temperature can be raised in a short time.
[0098]
(5) Since the heat value is proportional to the current value, the heat value can be quickly controlled by controlling the current value.
[0099]
(6) Since the portion to be heated by rotating the reel by the rotating mechanism can be dispersed, the temperature distribution of the protective plate can be made uniform.
[0100]
Here, as the rotating mechanism, one capable of controlling the speed by changing the speed based on the amounts of the substrate and the protective tape wound on the reel is suitably used.
[0101]
An apparatus for manufacturing a flexible wiring board according to claim 9 is a manufacturing apparatus for realizing the method for manufacturing a flexible wiring board according to claim 3, comprising: a. A substrate supply reel for delivering a substrate having a circuit pattern formed on a surface thereof; b. A transport unit for transporting the substrate delivered from the substrate supply reel on the upper surface; c. An application unit that is provided downstream in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape; d. A heating element and a heat medium that comes into contact with the substrate are provided downstream from the coating section in the conveyance direction of the conveyance section, and have a heat medium that contacts the substrate. A heating and drying unit for drying the surface of the solder resist layer by contacting the same; e. A protection tape supply reel that is provided downstream from the heating and drying unit in the transport direction of the transport unit and that sends out a protective tape laminated on the upper surface of the substrate; f. A reel that is provided downstream from the protective tape supply reel in the transport direction of the transport unit and has a protective plate on both sides, and a substrate on which a solder resist layer is formed in a roll shape via the protective tape; , G. The reel having the substrate and the protective tape wound thereon is configured to include a heat curing unit that performs high-temperature heating to cure the solder resist layer.
[0102]
With this configuration, the following operation is obtained.
[0103]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0104]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0105]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0106]
An apparatus for manufacturing a flexible wiring board according to a tenth aspect is a manufacturing apparatus for realizing the method for manufacturing a flexible wiring board according to the fifth aspect, comprising: a. A substrate supply reel for delivering a substrate having a circuit pattern formed on a surface thereof; b. A transport unit for transporting the substrate delivered from the substrate supply reel on the upper surface; c. An application unit that is provided downstream in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape; d. A heating element and a heat medium that comes into contact with the substrate are provided downstream from the coating section in the conveyance direction of the conveyance section, and have a heat medium that contacts the substrate. A heating and drying unit for drying the surface of the solder resist layer by contacting the same; e. A protection tape supply reel that is provided downstream from the heating and drying unit in the transport direction of the transport unit and that sends out a protective tape laminated on the upper surface of the substrate; f. A reel that is provided downstream from the protective tape supply reel in the transport direction of the transport unit and has a protective plate on both sides, and a substrate on which the solder resist layer is formed is wound into a roll via a protective tape, g. A rotation mechanism disposed at both ends of the reel for rotating the reel; h. A heat-curing section having at least one magnetic field generating coil disposed at least on one of the outer surface sides of the protective plate with a space therebetween and inductively heating the protective plate with a magnetic field generated by the magnetic field generating coil; have.
[0107]
With this configuration, the following operation is obtained.
[0108]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0109]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0110]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0111]
(4) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0112]
(5) Since the operations of winding and heat drying and curing can be performed at the same time, heat curing can be performed efficiently in a short time.
[0113]
(6) Heating can be performed at a low temperature because it is heated, dried and cured while being wound.
[0114]
(7) The magnetic field generated by applying a high-frequency current to the magnetic field generating coil generates an eddy current on the surface of the protective plate, and the protective plate is heated using the induction heating in which the Joule heat of the generated eddy current generates heat. The temperature can be raised in a short time.
[0115]
(8) Since the heat value is proportional to the current value, the heat value can be quickly controlled by controlling the current value.
[0116]
(9) Since the portion to be heated by rotating the reel by the rotation mechanism can be dispersed, the temperature distribution of the protective plate can be made uniform.
[0117]
An apparatus for manufacturing a flexible wiring board according to claim 11 is the apparatus for manufacturing a flexible wiring board according to claim 9 or 10, wherein the heating medium is disposed at both ends in the lateral direction of the upper surface of the heat medium and the both ends of the substrate are heated medium. And an L-shaped rail portion to be conveyed while being sandwiched between the gaps.
[0118]
According to this configuration, the following operation is obtained in addition to the operation obtained in claim 9 or 10.
[0119]
(1) Since the substrate is transported by scissors by the rail portion, it is possible to prevent the substrate from deflecting into an arc due to thermal contraction generated when drying the surface of the insulating ink.
[0120]
(2) Since the substrate can be prevented from being curved in an arc, uneven heating can be eliminated and uniform drying can be performed in a short time.
[0121]
As the heating element, a heat exchanger such as a nichrome wire or hot water is used. Particularly, a nichrome wire is preferably used because it generates a large amount of heat.
[0122]
As the shape of the heating element, a rod shape, a U shape, an M shape, an S shape which is bent at least twice or the like is used. In particular, an S-shape curved at least twice is preferably used because there is no unevenness in the temperature distribution.
[0123]
The length of the heat medium needs to be long enough to dry the surface, but a length of 50 to 500 mm is preferably used. When the length is shorter than 50 mm, the time for drying the solder resist layer surface tends to be insufficient, and when the length is longer than 500 mm, the frictional force between the heat medium or the rail portion and the substrate increases, thereby damaging the substrate. Since there is a tendency, none of them is preferable.
[0124]
For the rail portion, for example, aluminum, copper, stainless steel or the like is used similarly to the heat medium. In particular, aluminum is preferably used because it has excellent heat dissipation characteristics.
[0125]
The gap between the rail portion and the heat medium is preferably 0.1 to 1.0 mm. When the thickness is smaller than 0.1 mm, the frictional force between the heat medium or the rail portion and the substrate tends to increase, and the substrate tends to be damaged. When the thickness is larger than 1 mm, the substrate is warped or the temperature distribution is uneven. All of these are not preferred because of the tendency to occur.
[0126]
According to a twelfth aspect of the present invention, there is provided the flexible wiring board manufacturing apparatus according to any one of the ninth to eleventh aspects, wherein the flexible wiring board manufacturing apparatus is disposed above the heating and drying unit and exhausted to the outside. And a configuration provided with an external exhaust air intake hole for performing the following.
[0127]
With this configuration, the following operation is obtained in addition to the operation obtained in any one of the ninth to eleventh aspects.
[0128]
(1) The lead surface can be prevented from being contaminated by the vapor of the solvent by discharging the solvent of the vaporized solder resist layer to the outside.
[0129]
Here, as for the location of the external exhaust air intake holes, a method of arranging them on the upper surface of the substrate and a method of arranging them on the side surfaces of the substrate are used. In particular, the method of disposing on the upper surface of the substrate is preferably used because the generated solvent vapor can be efficiently discharged.
[0130]
According to a thirteenth aspect of the present invention, at least an application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on a surface to form a solder resist layer in a predetermined shape, and the solder resist layer is formed. A heating and curing step of drying and curing the solder resist layer while winding the substrate into a roll via a protective tape.Since the work of winding and heating and drying and curing can be performed simultaneously, Heat curing can be performed efficiently in a short time.
[0131]
According to a fourteenth aspect of the present invention, in the thirteenth aspect, a heating and drying step for drying the surface of the solder resist layer is provided between the coating step and the heat curing step. Only the components are vaporized to increase the viscosity of the solder resist layer, so that only the surface can be dried in a short time. By drying the surface, the pattern shape of the solder resist layer can be maintained.
[0132]
Hereinafter, embodiments of the present invention will be described with reference to FIGS. 1 to 16.
[0133]
(Embodiment 1)
FIG. 1 is a perspective view showing a method for manufacturing a flexible wiring board and a manufacturing apparatus for realizing the manufacturing method in the first embodiment, FIG. 6 is an enlarged view of A in FIG. 1, and FIG. FIG. 8 is a sectional view taken along the arrow B, and FIG. 8 is an enlarged view of FIG.
[0134]
1, 6 or 8, 1 is a substrate supply reel made of aluminum or the like, 2 is a substrate made of polyimide-based insulating resin or the like sent from the substrate supply reel 1, and 3 is an upper surface of the substrate 2. After bonding a metal foil such as copper, a circuit is formed by arranging an etching resist layer on the required part by photolithography or printing and removing unnecessary parts with an etching solution such as an aqueous solution of ferric chloride. Reference numeral 4 denotes a transport unit composed of a belt conveyor or the like that transports the substrate 2 on which the circuit pattern 3 is formed. Reference numeral 5 denotes an insulating ink, which will be described later, applied to the upper surface of the substrate 2 on which the circuit pattern 3 is formed. A coating part 6 for forming a solder resist layer is made of an epoxy resin as a curing agent for a polyimide resin using γ-butyrolactone or triethylene glycol dimethyl ether as a solvent. , A solder resist layer formed on the upper surface of the substrate 2 by the coating unit 5, a protective tape supply reel 8 for supplying a protective tape, which will be described later, and made of plastic or the like, and 9 for a polyimide. A protective tape 10 made of an embossed tape or the like using a system material, a reel 2 made of aluminum or the like, which winds the protective tape 9 and a substrate 2 having a protective plate to be described later on both sides and on which a solder resist layer 7 is formed; Reference numeral 11 denotes a disk-shaped protective plate made of aluminum or the like, 12 denotes a heat-curing unit that includes a heating body described below and heat-cures the solder resist layer 7 formed on the upper surface of the substrate 2, and 13 controls the temperature of the heating body described below. A temperature control device for a heating element, 14 is a power supply, 15 is a heating element buried in the protection plate 11 and configured to heat the protection plate 11 and made of a sheath heater, etc. A coating step 17 of forming the solder resist layer 7 by applying the rim ink 6, a step 17, which is wound around a reel 10 via a protective tape 9 on the upper surface of the substrate 2 on which the solder resist layer 7 is formed, A heating and curing step of heating and curing the resist layer 7; a screen 29 for coating the substrate 2 on which the solder resist layer 7 is formed and applying the insulating ink 6 to the upper surface of the substrate 2 by passing through a pattern portion of a screen plate to be described later. Reference numeral 30 denotes a pattern portion for screen plate making, and 31 denotes a squeegee for uniformly applying the insulating ink 6.
[0135]
A method for manufacturing a flexible wiring board configured as described above and a manufacturing apparatus for realizing the manufacturing method will be described with reference to FIGS.
[0136]
In the coating step 16, first, the circuit pattern 3 on the upper surface of the substrate 2 is formed by attaching a metal foil such as copper to the surface of the substrate 2 and then arranging an etching resist layer on a necessary portion by photolithography or printing to form a chloride. It is formed by removing unnecessary portions with an etching solution such as an aqueous solution of diiron. As shown in FIG. 1, a substrate 2 on which a circuit pattern 3 is formed is supplied from a substrate supply reel 1, and is transported horizontally on the upper surface of a transport unit 4. Next, as shown in FIG. 6, after the screen plate 29 is coated on the upper surface of the substrate 2 on which the circuit pattern 3 is formed in the coating section 5, the insulating ink 6 is injected from above the screen plate 29, and the squeegee 31 is formed. The solder resist layer 7 is formed by uniformly applying the insulating ink 6 to the upper surface of the substrate 2 from the pattern portion 30 of the screen plate making.
[0137]
Next, in the heat curing step, as shown in FIG. 1, the substrate 2 on which the solder resist layer 7 is formed is transported on the upper surface of the transport unit 4 and the protective tape 9 supplied from the protective tape supply reel 8 is removed. 2 on the upper surface. Next, the substrate 2 and the protective tape 9 are wound around a reel 10 having protective plates 11 on both sides. Next, in the heat curing section 12, the heating element 15 is controlled by the heating element temperature controller 13 to heat the protection plate 11, and the solder resist layer on the surface of the substrate 2 is generated by heat conduction and heat radiation from the protection plate 11. 7 is cured by heating.
[0138]
Since the apparatus for manufacturing a flexible wiring board according to Embodiment 1 is configured as described above, it has the following operation.
[0139]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0140]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0141]
(Embodiment 2)
FIG. 2 is a perspective view showing a method for manufacturing a flexible wiring board according to Embodiment 2 and a manufacturing apparatus for realizing the manufacturing method. FIG. 9 is an enlarged view of C in FIG. 2, and FIG. FIG. 11 is a cross-sectional view as viewed from an arrow E. FIG. 11 is a perspective view illustrating the principle of induction heating.
[0142]
2 to 9 to 11, reference numeral 18 denotes a rotating mechanism for rotating the reel 10, reference numeral 19 denotes a magnetic field generating coil made of copper or the like and arranged on both sides on the outer surface side of the protection plate, and reference numeral 20 denotes a temperature of the protection plate 11. A temperature control device for a magnetic field generating coil that measures and controls the current flowing to the magnetic field generating coil 19. When the temperature is set to the same condition as the drying and curing temperature of the insulating ink 6, the solvent is vaporized from the surface of the solder resist layer described later. This is preferable since the surface viscosity can be increased and the surface can be cured. 21 is a high frequency inverter, 32 is a magnetic field generated by the magnetic field generating coil 19, and 33 is an eddy current generated on the surface of the protection plate 11 by the magnetic field 32.
[0143]
A method for manufacturing a flexible wiring board configured as described above and a manufacturing apparatus for realizing the manufacturing method will be described with reference to FIGS. 2, 6, 9, and 11. FIG.
[0144]
The application step 16 is the same as in the first embodiment, and a description thereof will be omitted.
[0145]
Next, in the heat curing step, as shown in FIG. 2, the substrate 2 on which the solder resist layer 7 is formed is transported on the upper surface of the transport unit 4 and the protective tape 9 supplied from the protective tape supply reel 8 is attached to the substrate. 2 on the upper surface. Next, the substrate 2 and the protective tape 9 are wound around a reel 10 having protective plates 11 on both sides. Next, in the heat-curing unit 12, a high-frequency current generated by the high-frequency inverter 21 is controlled by the magnetic-field-generating-coil temperature control device 20, and a magnetic field is generated from the magnetic-field-generating coils 19 arranged on both sides of the protection plate 11, for example, in a square shape. Then, the surface of the protection plate 11 is induction-heated while rotating the reel 10 by the rotation mechanism 18, and the solder resist layer 7 on the surface of the substrate 2 is heated and cured by heat conduction and heat radiation from the protection plate 11.
[0146]
Since the apparatus for manufacturing a flexible wiring board according to the second embodiment is configured as described above, it has the following operation.
[0147]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0148]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0149]
(3) Heating can be performed at a low temperature because it is heated, dried and cured while being wound.
[0150]
(4) The magnetic field generated by applying a high-frequency current to the magnetic field generating coil generates an eddy current on the surface of the protection plate, and the protection plate is heated using the induction heating in which the Joule heat of the generated eddy current generates heat. The temperature can be raised in a short time.
[0151]
(5) Since the heat value is proportional to the current value, the heat value can be quickly controlled by controlling the current value.
[0152]
(6) Since the portion to be heated by rotating the reel by the rotating mechanism can be dispersed, the temperature distribution of the protective plate can be made uniform.
[0153]
(Embodiment 3)
FIG. 3 is a perspective view showing a method for manufacturing a flexible wiring board according to Embodiment 3 and a manufacturing apparatus for realizing the manufacturing method. FIG. 12 is a plan view of a heating and drying unit excluding a rail portion. FIG. 14 is a cross-sectional view taken along the line GG of FIG. 12, and FIG.
[0154]
3 and 12 to 14, reference numeral 22 denotes a heat medium which is made of aluminum or the like and which is in contact with the substrate 2 and which is disposed on the upper surface of a heat dispersing plate, which will be described later. A heating and drying unit for drying the surface of the formed solder resist layer 7; 24, a temperature control device for a heating medium; 25, an external exhaust air inlet for discharging solvent vapor generated when the surface of the solder resist layer 7 is dried; , 26 is a hot air blower for hardening the surface-dried solder resist layer 7 with high-temperature hot air, 27 is hot air generated from a hot air blower 27, and 28 is heating for drying the surface of the solder resist layer 7 on the upper surface of the substrate 2. This is a drying step. Reference numeral 34 denotes a heating element buried in an insulator to be described later and made of a nichrome wire or the like; 35, an insulator buried and holding the heating element 34; 36, a heating element 34 disposed on the upper surface of the insulator 35; A heat dispersing plate made of a mica plate or the like for uniformly dispersing the heat generated from the heating medium 22 to the heat medium 22; a heat dispersing plate 37 disposed on the upper surface of the heat medium 22 and having the solder resist layer 7 formed thereon; It is a rail part to fit.
[0155]
Here, as the heating element 34, a heat exchanger such as a nichrome wire or hot water is used. Particularly, a nichrome wire is preferably used because it generates a large amount of heat. Further, as the shape of the heating element 34, a bar shape, a U shape, an M shape, an S shape which is curved at least twice or more, and the like are used. In particular, an S-shape curved at least twice is preferably used because there is no unevenness in the temperature distribution.
[0156]
As the heat dispersion plate 36, a mica plate, an acrylic plate, a polycarbonate plate, or the like is used. In particular, a mica plate made of mica is preferably used because it is excellent in heat resistance and electrical insulation and can be easily thinned to about 0.2 to 1 mm.
[0157]
Further, the length of the heat medium 22 needs to be long enough to dry the surface, but a length of 50 to 500 mm is preferably used. As the length is shorter than 50 mm, the time for drying the surface of the solder resist layer tends to be insufficient, and when the length is longer than 500 mm, the frictional force between the heat medium 22 or the rail portion 37 and the substrate 2 increases, and All of these are not preferred because there is a tendency to damage them. For the rail portion 37, for example, aluminum, copper, stainless steel, or the like is used similarly to the heat medium. In particular, aluminum is preferably used because it has excellent heat dissipation characteristics.
[0158]
The gap between the rail 37 and the heat medium 22 is preferably 0.1 to 1.0 mm. As the thickness is smaller than 0.1 mm, the frictional force between the heat medium 22 or the rail portion 37 and the substrate 2 increases, and the substrate tends to be damaged. Both tend to cause unevenness in the distribution, which is not preferable.
[0159]
In the third embodiment, the shape of the heating element 34 is S-shaped, and the length of the heating medium 22 is 300 mm, and the heating medium 34 is controlled at a speed of contacting the substrate 2 for 20 seconds to 1 minute. The temperature of the heat medium 22 was 70 to 120 ° C., the thickness of the heat dispersion plate 36 was 0.2 to 1 mm, and the gap between the rail 37 and the heat medium 22 was 0.5 mm.
[0160]
A method for manufacturing the flexible wiring board configured as described above and a manufacturing apparatus for realizing the manufacturing method will be described with reference to FIGS. 3, 6, 12, and 14.
[0161]
The application step 16 is the same as in the first embodiment, and a description thereof will be omitted.
[0162]
Next, in the heating and drying step, the substrate 2 on which the solder resist layer is formed is transported by the transport unit 4 as shown in FIG. Next, as shown in FIGS. 3 and 14, in the heating / drying unit 23, the heat generated from the heating element 34 controlled by the temperature control device 24 for the heat medium is evenly dispersed by the heat dispersion plate 36 without temperature unevenness. . Next, heat is conducted from the heat dispersion plate 36 to the heat medium 22 by heat conduction, and further from the heat medium 22 to the back surface of the substrate 2 to dry the surface of the solder resist layer 7. At this time, the warpage caused by the difference in internal stress between the portion having the solder resist layer 7 and the portion not having the solder resist layer 7 is prevented by being pressed by the rail portion 37. In addition, the vapor of the solvent generated when the surface is dried is discharged to the outside through the exhaust hole 25 for external exhaust. Next, the substrate 2 having the solder resist layer 7 whose surface has been dried is transported by the transport unit 4, and hot air 27 is generated from a hot air blower 26 to cure the solder resist layer.
[0163]
Since the apparatus for manufacturing a flexible wiring board according to the third embodiment is configured as described above, it has the following operation.
[0164]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0165]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0166]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0167]
(4) Since the substrate is conveyed by scissors by the rails, the substrate can be prevented from being curved in an arc due to thermal shrinkage generated when drying the surface of the insulating ink.
[0168]
(5) Since the substrate can be prevented from skewing in an arc, uneven heating can be eliminated and uniform drying can be performed in a short time.
[0169]
(6) Since heat from the heating element can be uniformly dispersed by the heat dispersion plate, uniform drying can be performed.
[0170]
(7) By discharging the solvent of the vaporized solder resist layer to the outside, contamination of the lead surface by the vapor of the solvent can be prevented.
[0171]
(Embodiment 4)
FIG. 4 is a perspective view showing a method for manufacturing a flexible wiring board according to Embodiment 4 and a manufacturing apparatus for realizing the manufacturing method. A method for manufacturing a flexible wiring board and a manufacturing apparatus for realizing the manufacturing method according to the fourth embodiment will be described with reference to FIGS.
[0172]
The application step 16 is the same as in the first embodiment, and a description thereof will be omitted.
[0173]
Next, in the heating and drying step 28, as in the third embodiment, the substrate 2 on which the solder resist layer is formed is transported by the transport unit 4. Next, as shown in FIGS. 4 and 14, in the heating and drying unit 23, the heat generated from the heating element 34 controlled by the temperature control device 24 for the heat medium is evenly dispersed by the heat distribution plate 36 without temperature unevenness. . Next, heat is conducted from the heat dispersing plate 36 to the heat medium 22 by heat conduction, and further from the heat medium 22 to the back surface of the substrate 2, and the surface of the solder resist layer 7 is dried while maintaining a temperature of 70 to 120 ° C. At this time, warping caused by a difference in internal stress between a portion having the solder resist layer 7 and a portion not having the solder resist layer 7 is prevented by being pressed by the rail portion 37. In addition, the vapor of the solvent generated when the surface is dried is discharged to the outside through the exhaust hole 25 for external exhaust.
[0174]
Next, in the heat curing step 17, the substrate 2 on which the solder resist layer 7 is formed is transported on the upper surface of the transport unit 4 and the protective tape 9 supplied from the protective tape supply reel 8 is removed, as in the first embodiment. It is laminated on the upper surface of the substrate 2. Next, the substrate 2 and the protective tape 9 are wound around a reel 10 having protective plates 11 on both sides. Next, in the heat curing section 12, the heating body 15 is controlled by the heating body temperature controller 13 to heat the protection plate 11, and a temperature of 120 to 180 ° C. is maintained by heat conduction and heat radiation from the protection plate 11, The solder resist layer 7 on the surface of the substrate 2 is cured by heating.
[0175]
Since the apparatus for manufacturing a flexible wiring board according to the fourth embodiment is configured as described above, it has the following operation.
[0176]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0177]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0178]
(3) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0179]
(4) By drying the surface, the solder resist layer can be cured while maintaining the pattern shape thereof, so that the circuit is excellent in reliability and insulation.
[0180]
(5) Since the surface can be set to a high temperature in the heat curing step by drying the surface, the drying time can be shortened.
[0181]
(6) Since the substrate is conveyed by scissors by the rails, it is possible to prevent the substrate from deflecting into an arc due to thermal shrinkage generated when drying the surface of the insulating ink.
[0182]
(7) Since the substrate can be prevented from skewing in an arc, uneven heating can be eliminated and uniform drying can be performed in a short time.
[0183]
(8) Since heat from the heating element can be uniformly dispersed by the heat dispersion plate, uniform drying can be performed.
[0184]
(9) By discharging the solvent of the vaporized solder resist layer to the outside, contamination of the lead surface due to the vapor of the solvent can be prevented.
[0185]
(Embodiment 5)
FIG. 5 is a perspective view showing a method for manufacturing a flexible wiring board according to Embodiment 5 and a manufacturing apparatus for realizing the manufacturing method. Fifth Embodiment A method for manufacturing a flexible wiring board and a manufacturing apparatus for realizing the manufacturing method according to the fifth embodiment will be described with reference to FIGS. 5, 6, 9 and 14.
[0186]
The application step 16 is the same as in the first embodiment, and a description thereof will be omitted.
[0187]
Next, in the heating and drying step 28, as in the third embodiment, the substrate 2 on which the solder resist layer is formed is transported by the transport unit 4. Next, as shown in FIGS. 5 and 14, in the heating and drying unit 23, the heat generated from the heating element 34 controlled by the temperature control device 24 for the heat medium is evenly dispersed by the heat distribution plate 36 without temperature unevenness. . Next, heat is conducted from the heat dispersing plate 36 to the heat medium 22 by heat conduction, and further from the heat medium 22 to the back surface of the substrate 2, and the surface of the solder resist layer 7 is dried while maintaining a temperature of 70 to 120 ° C. At this time, warping caused by a difference in internal stress between a portion having the solder resist layer 7 and a portion not having the solder resist layer 7 is prevented by being pressed by the rail portion 37. In addition, the vapor of the solvent generated when the surface is dried is discharged to the outside through the exhaust hole 25 for external exhaust.
[0188]
Next, in the heating and curing step 17, similarly to the second embodiment, the substrate 2 on which the solder resist layer 7 is formed is transported on the upper surface of the transport unit 4 and the protective tape 9 supplied from the protective tape supply reel 8 is removed. It is laminated on the upper surface of the substrate 2. Next, the substrate 2 and the protective tape 9 are wound around a reel 10 having protective plates 11 on both sides. Next, in the heat-curing unit 12, a high-frequency current generated by the high-frequency inverter 21 is controlled by the magnetic-field-generating-coil temperature control device 20, and a magnetic field is generated from the magnetic-field-generating coils 19 arranged on both sides of the protection plate 11, for example, in a square shape. The surface of the protection plate 11 is induction-heated while rotating the reel 10 by the rotation mechanism 18, and the temperature of 120 to 180 ° C. is maintained by heat conduction and heat radiation from the protection plate 11, and the solder resist layer 7 on the surface of the substrate 2 is heated. Is cured by heating.
[0189]
Since the manufacturing apparatus of the flexible wiring board according to the fifth embodiment is configured as described above, it has the following operation.
[0190]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0191]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0192]
(3) Heating can be performed at a low temperature because it is heated, dried and cured while being wound.
[0193]
(4) The magnetic field generated by applying a high-frequency current to the magnetic field generating coil generates an eddy current on the surface of the protection plate, and the protection plate is heated using the induction heating in which the Joule heat of the generated eddy current generates heat. The temperature can be raised in a short time.
[0194]
(5) Since the heat value is proportional to the current value, the heat value can be quickly controlled by controlling the current value.
[0195]
(6) Since the portion to be heated by rotating the reel by the rotating mechanism can be dispersed, the temperature distribution of the protective plate can be made uniform.
[0196]
(7) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0197]
(8) Since the pattern can be maintained and cured by drying the surface to maintain the solder resist layer pattern, the circuit is excellent in reliability and insulation.
[0198]
(9) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0199]
(10) Since the substrate is transported by scissors by the rails, it is possible to prevent the substrate from deflecting into an arc due to thermal contraction generated when drying the surface of the insulating ink.
[0200]
(11) Since the substrate can be prevented from skewing in an arc shape, uneven heating is eliminated, and uniform drying can be performed in a short time.
[0201]
(12) Since heat from the heating element can be uniformly dispersed by the heat dispersion plate, uniform drying can be performed.
[0202]
(13) By discharging the solvent of the vaporized solder resist layer to the outside, contamination of the lead surface due to the vapor of the solvent can be prevented.
[0203]
As described above, according to the first to fifth embodiments, a flexible wiring board having an excellent end portion shape can be obtained as shown in FIGS. 15 and 16, and the protective plate according to the first to fifth embodiments can be obtained. However, by providing a cushioning covering material made of rubber or the like on the outside, the cushioning covering material mitigates an external impact, and the buffer covering material blocks heat released from the outer surface of the protective plate. It is conceivable to make it excellent in resource saving.
[0204]
【The invention's effect】
As described above, the method for manufacturing a flexible wiring board according to claim 1 of the present invention includes:
a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
b. On a reel having protective plates on both sides, the substrate on which the solder resist layer is formed is wound into a roll via a protective tape, and is embedded inside the protective plate or on the outer surface side of the protective plate. A heat-curing step of drying and curing the solder resist layer by heating the protective plate with a heat-curing unit having at least one heating element disposed at intervals on at least one side;
Is provided.
[0205]
With this configuration, the following effects can be obtained.
[0206]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0207]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0208]
The method for manufacturing a flexible wiring board according to claim 2 of the present invention includes:
a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
b. On a reel having a protective plate on both sides, the substrate on which the solder resist layer is formed is wound up in a roll form via a protective tape, and at least the outer surface side of the protective plate is rotated while rotating the reel by a rotating mechanism. A heat-curing step of drying and curing the solder resist layer by inductively heating the protective plate by a heat-curing unit having one or more magnetic field generating coils arranged at intervals on one side;
Is provided.
[0209]
With this configuration, the following effects can be obtained.
[0210]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0211]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0212]
(3) Heating can be performed at a low temperature because it is heated, dried and cured while being wound.
[0213]
(4) The magnetic field generated by applying a high-frequency current to the magnetic field generating coil generates an eddy current on the surface of the protection plate, and the protection plate is heated using the induction heating in which the Joule heat of the generated eddy current generates heat. The temperature can be raised in a short time.
[0214]
(5) Since the heat value is proportional to the current value, the heat value can be quickly controlled by controlling the current value.
[0215]
(6) Since the portion to be heated by rotating the reel by the rotating mechanism can be dispersed, the temperature distribution of the protective plate can be made uniform.
[0216]
The method for producing a flexible wiring board according to claim 3 of the present invention comprises the steps of: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
b. Immediately after the coating step, in a heating and drying unit having a heating element and a heating medium in contact with the substrate, heat generated from the heating element is conducted to the heating medium to bring the substrate into contact with the heating medium. A heating and drying step for drying the surface of the solder resist layer,
c. A heat-curing step of heating the substrate holding the surface-dried solder resist layer at a high temperature by a heat-curing unit to cure the solder resist layer,
Is provided.
[0219]
With this configuration, the following effects can be obtained.
[0218]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0219]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0220]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0221]
The method for manufacturing a flexible wiring board according to claim 4 of the present invention comprises:
a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
b. Immediately after the coating step, in a heating and drying unit having a heating element and a heating medium in contact with the substrate, heat generated from the heating element is conducted to the heating medium to bring the substrate into contact with the heating medium. A heating and drying step for drying the surface of the solder resist layer,
c. On a reel having protective plates on both sides, the substrate holding the solder resist layer whose surface has been dried is wound into a roll via a protective tape, and is buried inside the protective plate or the outer surface of the protective plate. A heat-curing step of curing the solder resist layer by heating the protective plate with a heat-curing unit having at least one heating element disposed at an interval on at least one of the sides;
Is provided.
[0222]
With this configuration, the following effects can be obtained.
[0223]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0224]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0225]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0226]
(4) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat conduction from the protective plate, it is possible to efficiently heat and dry and cure.
[0227]
(5) Since the operations of winding and heat drying and curing can be performed at the same time, heat curing can be performed efficiently in a short time.
[0228]
The method for manufacturing a flexible wiring board according to claim 5 of the present invention comprises:
a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
b. Immediately after the coating step, in a heating and drying unit having a heating element and a heating medium in contact with the substrate, heat generated from the heating element is conducted to the heating medium to bring the substrate into contact with the heating medium. A heating and drying step for drying the surface of the solder resist layer,
c. On a reel having a protective plate on both sides, the substrate on which the solder resist layer is formed is wound up in a roll form via a protective tape, and at least the outer surface side of the protective plate is rotated while rotating the reel by a rotating mechanism. A heat-curing step of curing the solder resist layer by inductively heating the protective plate by a heat-curing unit having one or more magnetic field generating coils arranged at intervals on one side;
Is provided.
[0229]
With this configuration, the following effects can be obtained.
[0230]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0231]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0232]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0233]
(4) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat conduction from the protective plate, it is possible to efficiently heat and dry and cure.
[0234]
(5) Since the operations of winding and heat drying and curing can be performed at the same time, heat curing can be performed efficiently in a short time.
[0235]
(6) Heating can be performed at a low temperature because it is heated, dried and cured while being wound.
[0236]
(7) The magnetic field generated by applying a high-frequency current to the magnetic field generating coil generates an eddy current on the surface of the protective plate, and the protective plate is heated using the induction heating in which the Joule heat of the generated eddy current generates heat. The temperature can be raised in a short time.
[0237]
(8) Since the heat value is proportional to the current value, the heat value can be quickly controlled by controlling the current value.
[0238]
(9) Since the portion to be heated by rotating the reel by the rotation mechanism can be dispersed, the temperature distribution of the protective plate can be made uniform.
[0239]
The method of manufacturing a flexible wiring board according to claim 6 of the present invention is the method of manufacturing a flexible wiring board according to any one of claims 3 to 5, wherein the heat medium that contacts the substrate is provided. Have a surface temperature (Ts) of 70 ° C. <Ts <120 ° C.
[0240]
With this configuration, the following effect can be obtained in addition to the effect described in any one of the third to fifth aspects.
[0241]
(1) Since bubbles can be prevented from being generated due to vaporization of the solvent from the solder resist layer, and the surface drying of the solder resist layer can be improved, the circuit is excellent in reliability and insulation.
[0242]
An apparatus for manufacturing a flexible wiring board according to claim 7 of the present invention is a manufacturing apparatus for realizing the method for manufacturing a flexible wiring board according to claim 1,
a. A substrate supply reel for sending out a substrate on which a circuit pattern is formed,
b. A transport unit that transports the substrate placed on the upper surface and transported from the substrate supply reel,
c. An application unit that is provided on the downstream side in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape,
d. A protection tape supply reel that is disposed downstream from the coating unit in the transport direction of the transport unit and that sends out a protective tape stacked on the upper surface of the substrate;
e. The protection tape supply reel is provided on the downstream side in the transport direction of the transport unit with a protection plate on both sides, and the substrate on which the solder resist layer is formed is formed into a roll via the protection tape. Reel to wind,
f. Having at least one heating element buried inside the protection plate or disposed at least on the outer surface side of the protection plate at an interval, heating the protection plate to form the solder resist layer A heat curing unit for drying and curing,
Is provided.
[0243]
With this configuration, the following effects can be obtained.
[0244]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0245]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0246]
An apparatus for manufacturing a flexible wiring board according to claim 8 of the present invention is a manufacturing apparatus for realizing the method for manufacturing a flexible wiring board according to claim 2,
a. A substrate supply reel for sending out a substrate on which a circuit pattern is formed,
b. A transport unit that transports the substrate placed on the upper surface and transported from the substrate supply reel,
c. An application unit that is provided on the downstream side in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape,
d. A protection tape supply reel that is disposed downstream from the coating unit in the transport direction of the transport unit and that sends out a protective tape stacked on the upper surface of the substrate;
e. The protection tape supply reel is provided on the downstream side in the transport direction of the transport unit with a protection plate on both sides, and the substrate on which the solder resist layer is formed is formed into a roll via the protection tape. Reel to wind,
f. A rotation mechanism disposed at both ends of the reel to rotate the reel;
g. A heat-curing unit having one or more magnetic field generating coils arranged at intervals on at least one of the outer surface sides of the protective plate, and inductively heating the protective plate with a magnetic field generated by the magnetic field generating coil,
Is provided.
[0247]
With this configuration, the following effects can be obtained.
[0248]
(1) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat from the protective plate, it is possible to efficiently heat and dry and cure.
[0249]
(2) Since the operations of winding and heat-drying and curing can be performed simultaneously, heat-curing can be efficiently performed in a short time.
[0250]
(3) Heating can be performed at a low temperature because it is heated, dried and cured while being wound.
[0251]
(4) The magnetic field generated by applying a high-frequency current to the magnetic field generating coil generates an eddy current on the surface of the protection plate, and the protection plate is heated using the induction heating in which the Joule heat of the generated eddy current generates heat. The temperature can be raised in a short time.
[0252]
(5) Since the heat value is proportional to the current value, the heat value can be quickly controlled by controlling the current value.
[0253]
(6) Since the portion to be heated by rotating the reel by the rotating mechanism can be dispersed, the temperature distribution of the protective plate can be made uniform.
[0254]
An apparatus for manufacturing a flexible wiring board according to claim 9 of the present invention is a manufacturing apparatus for realizing the method for manufacturing a flexible wiring board according to claim 3,
a. A substrate supply reel for sending out a substrate on which a circuit pattern is formed,
b. A transport unit that transports the substrate placed on the upper surface and transported from the substrate supply reel,
c. An application unit that is provided on the downstream side in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape,
d. The heating unit, which is provided downstream from the coating unit in the transport direction of the transport unit and has a heating medium in contact with the substrate, conducts heat generated by the heating unit to the heating medium. A heating and drying unit for drying the surface of the solder resist layer by contacting the substrate with the heating medium,
e. A protection tape supply reel that is provided downstream from the heating and drying unit in the transport direction of the transport unit and that sends out a protective tape to be stacked on the upper surface of the substrate;
f. The protection tape supply reel is provided on the downstream side in the transport direction of the transport unit with a protection plate on both sides, and the substrate on which the solder resist layer is formed is formed into a roll via the protection tape. Reel to wind,
g. The substrate and the reel around which the protective tape has been wound, a heat-curing unit that performs high-temperature heating to cure the solder resist layer,
Is provided.
[0255]
With this configuration, the following effects can be obtained.
[0256]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0257]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0258]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0259]
An apparatus for manufacturing a flexible wiring board according to claim 10 of the present invention is a manufacturing apparatus for realizing the method for manufacturing a flexible wiring board according to claim 5,
a. A substrate supply reel for sending out a substrate on which a circuit pattern is formed,
b. A transport unit that transports the substrate placed on the upper surface and transported from the substrate supply reel,
c. An application unit that is provided on the downstream side in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape,
d. The heating unit, which is provided downstream from the coating unit in the transport direction of the transport unit and has a heating medium in contact with the substrate, conducts heat generated by the heating unit to the heating medium. A heating and drying unit for drying the surface of the solder resist layer by contacting the substrate with the heating medium,
e. A protection tape supply reel that is provided downstream from the heating and drying unit in the transport direction of the transport unit and that sends out a protective tape to be stacked on the upper surface of the substrate;
f. The protection tape supply reel is provided on the downstream side in the transport direction of the transport unit with a protection plate on both sides, and the substrate on which the solder resist layer is formed is formed into a roll via the protection tape. Reel to wind,
g. A rotation mechanism disposed at both ends of the reel to rotate the reel;
h. A heat-curing unit having one or more magnetic field generating coils arranged at intervals on at least one of the outer surface sides of the protective plate, and inductively heating the protective plate with a magnetic field generated by the magnetic field generating coil,
Is provided.
[0260]
With this configuration, the following operation is obtained.
[0261]
(1) Since the thickness of the substrate is small, it is easy to conduct heat by contacting with the heat medium, and the temperature of the insulating ink can be uniformly increased by heat conduction from the substrate. The viscosity of the solder resist layer is increased by vaporization, so that only the surface can be dried in a short time.
[0262]
(2) Since the pattern shape of the solder resist layer can be maintained and cured by drying the surface, the circuit is excellent in reliability and insulation.
[0263]
(3) Since the surface can be set to a high temperature in the heat curing step by drying, the drying time can be shortened.
[0264]
(4) Since the entire temperature is made uniform by heating the protective plate and conducting radiant heat and heat conduction from the protective plate, it is possible to efficiently heat and dry and cure.
[0265]
(5) Since the operations of winding and heat drying and curing can be performed at the same time, heat curing can be performed efficiently in a short time.
[0266]
(6) Heating can be performed at a low temperature because it is heated, dried and cured while being wound.
[0267]
(7) The magnetic field generated by applying a high-frequency current to the magnetic field generating coil generates an eddy current on the surface of the protective plate, and the protective plate is heated using the induction heating in which the Joule heat of the generated eddy current generates heat. The temperature can be raised in a short time.
[0268]
(8) Since the heat value is proportional to the current value, the heat value can be quickly controlled by controlling the current value.
[0269]
(9) Since the portion to be heated by rotating the reel by the rotation mechanism can be dispersed, the temperature distribution of the protective plate can be made uniform.
[0270]
An apparatus for manufacturing a flexible wiring board according to claim 11 of the present invention is the apparatus for manufacturing a flexible wiring board according to claim 9 or 10, wherein the flexible wiring board is provided at both ends in the lateral direction of the upper surface of the heat medium. It has a configuration provided with an L-shaped rail portion for transporting both ends sandwiched in the gap with the heat medium.
[0271]
With this configuration, the following effects can be obtained in addition to the effects obtained in claim 9 or 10.
[0272]
(1) Since the substrate is transported by scissors by the rail portion, it is possible to prevent the substrate from deflecting into an arc due to thermal contraction generated when drying the surface of the insulating ink.
[0273]
(2) Since the substrate can be prevented from being curved in an arc, uneven heating can be eliminated and uniform drying can be performed in a short time.
[0274]
An apparatus for manufacturing a flexible wiring board according to claim 12 of the present invention is the apparatus for manufacturing a flexible wiring board according to any one of claims 9 to 11, and is disposed above the heating and drying unit. It has a configuration provided with an external exhaust intake hole for exhausting to the outside.
[0275]
With this configuration, the following effect is obtained in addition to the effect obtained in any one of the ninth to eleventh aspects.
[0276]
(1) The lead surface can be prevented from being contaminated by the vapor of the solvent by discharging the solvent of the vaporized solder resist layer to the outside.
[0277]
According to a thirteenth aspect of the present invention, at least an application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on a surface to form a solder resist layer in a predetermined shape, and the solder resist layer is formed. A heat curing step of drying and curing the solder resist layer while winding the substrate into a roll via a protective tape.
[0278]
With this configuration, the following effects can be obtained.
[0279]
(1) Since the operations of winding and heat drying and curing can be performed at the same time, heat curing can be performed efficiently in a short time.
[0280]
According to a fourteenth aspect of the present invention, in the thirteenth aspect, a heating and drying step for drying the surface of the solder resist layer is provided between the coating step and the heat curing step.
[0281]
With this configuration, the following effect can be obtained in addition to the effect obtained by the thirteenth aspect.
[0282]
(1) Only the solvent component of the insulating ink is vaporized to increase the viscosity of the solder resist layer, so that only the surface can be dried in a short time. By drying the surface, the pattern shape of the solder resist layer is maintained. Can be.
[0283]
Therefore, according to the present invention, the solder resist layer can be heat-dried and cured at a uniform temperature efficiently in a short time without disturbing the pattern shape, and the insulation and reliability of the circuit are excellent, and the control during heating can be performed. It is possible to provide a method for manufacturing a flexible wiring board which is excellent in workability, workability, and resource saving and does not generate warpage, and it is possible to provide a manufacturing apparatus for a flexible wiring board which realizes the manufacturing method.
[Brief description of the drawings]
FIG. 1 is a perspective view showing a method for manufacturing a flexible wiring board and a manufacturing apparatus for realizing the method according to the first embodiment.
FIG. 2 is a perspective view showing a method of manufacturing a flexible wiring board according to a second embodiment and a manufacturing apparatus for realizing the manufacturing method;
FIG. 3 is a perspective view showing a method for manufacturing a flexible wiring board according to a third embodiment and a manufacturing apparatus for realizing the manufacturing method;
FIG. 4 is a perspective view showing a method for manufacturing a flexible wiring board and a manufacturing apparatus for realizing the manufacturing method according to the fourth embodiment.
FIG. 5 is a perspective view showing a method for manufacturing a flexible wiring board in Embodiment 5 and a manufacturing apparatus for realizing the manufacturing method.
FIG. 6 is an enlarged view of A in FIG. 1;
FIG. 7 is a sectional view taken along the line BB of FIG. 1;
8 is an enlarged view of D in FIG. 7;
FIG. 9 is an enlarged view of C in FIG. 2;
10 is a sectional view taken along the line EE in FIG. 9;
FIG. 11 is a perspective view showing the principle of induction heating.
FIG. 12 is a plan view of a heating and drying unit excluding a rail unit.
FIG. 13 is a sectional view taken along the line GG of FIG. 12;
FIG. 14 is a cross-sectional view of a heating and drying unit including a rail unit.
FIG. 15 is a perspective view of a completed flexible wiring board.
FIG. 16 is a sectional view taken along the line HH of FIG. 15;
FIG. 17 is an essential part cross-sectional view of the step of forming the circuit pattern on the substrate;
FIG. 18 is a sectional view of a main part of a substrate on which a circuit pattern is formed.
FIG. 19 is a sectional view of a principal part of a substrate covered with a screen plate.
FIG. 20 is a sectional view of a principal part of a substrate on which a solder resist layer is formed.
FIG. 21 is a perspective view of a step of winding a substrate on which a solder resist layer is formed.
FIG. 22 is a perspective view of a step of heating and curing in a hot air drying furnace.
FIG. 23 is an enlarged view of a portion I in FIG. 20;
[Explanation of symbols]
1 Board supply reel
2 substrate
3 Circuit pattern
4 Transport unit
5 Coating section
6 Insulating ink
7 Solder resist layer
8 Protective tape supply reel
9 Protection tape
10 reel
11 Protection plate
12 Heat curing section
13 Temperature control device for heating element
14 Power supply
15 Heating body
16 Coating process
17 Heat curing process
18 Rotation mechanism
19 Magnetic field generating coil
20 Temperature control device for magnetic field generating coil
21 High frequency inverter
22 Heat medium
23 Heat drying section
24 Temperature control device for heat medium
25 Inlet for external exhaust
26 hot air heater
27 Warm air
28 Heat drying process
29 screen plate making
30 Screen pattern making
31 Squeegee
32 magnetic field
33 Eddy current
34 Heating element
35 Insulator
36 Heat dispersion plate
37 Rail
38 substrate
39 metal foil
40 Etching resist layer
41 Circuit pattern
42 screen plate making
43 Solder resist layer
44 Flexible wiring board
45 Protective tape
46 reel
47 Hot air drying oven
48 hot air heater

Claims (14)

a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
b. On a reel having protective plates on both sides, the substrate on which the solder resist layer is formed is wound into a roll via a protective tape, and is embedded inside the protective plate or on the outer surface side of the protective plate. A heat-curing step of drying and curing the solder resist layer by heating the protective plate with a heat-curing unit having at least one heating element disposed at intervals on at least one side;
A method for manufacturing a flexible wiring board comprising: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
b. On a reel having a protective plate on both sides, the substrate on which the solder resist layer is formed is wound up in a roll form via a protective tape, and at least the outer surface side of the protective plate is rotated while rotating the reel by a rotating mechanism. A heat-curing step of drying and curing the solder resist layer by inductively heating the protective plate by a heat-curing unit having one or more magnetic field generating coils arranged at intervals on one side;
A method for manufacturing a flexible wiring board comprising: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
b. Immediately after the coating step, in a heating and drying unit having a heating element and a heating medium in contact with the substrate, heat generated from the heating element is conducted to the heating medium to bring the substrate into contact with the heating medium. A heating and drying step for drying the surface of the solder resist layer,
c. A heat-curing step of heating the substrate holding the surface-dried solder resist layer at a high temperature by a heat-curing unit to cure the solder resist layer,
A method for manufacturing a flexible wiring board comprising: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
b. Immediately after the coating step, in a heating and drying unit having a heating element and a heating medium in contact with the substrate, heat generated from the heating element is conducted to the heating medium to bring the substrate into contact with the heating medium. A heating and drying step for drying the surface of the solder resist layer,
c. On a reel having protective plates on both sides, the substrate holding the solder resist layer whose surface has been dried is wound into a roll via a protective tape, and is buried inside the protective plate or the outer surface of the protective plate. A heat-curing step of curing the solder resist layer by heating the protective plate with a heat-curing unit having at least one heating element disposed at an interval on at least one of the sides;
A method for manufacturing a flexible wiring board comprising: a. An application step of applying an insulating ink to an upper surface of a substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
b. Immediately after the coating step, in a heating and drying unit having a heating element and a heating medium in contact with the substrate, heat generated from the heating element is conducted to the heating medium to bring the substrate into contact with the heating medium. A heating and drying step for drying the surface of the solder resist layer,
c. On a reel having a protective plate on both sides, the substrate on which the solder resist layer is formed is wound up in a roll form via a protective tape, and at least the outer surface side of the protective plate is rotated while rotating the reel by a rotating mechanism. A heat-curing step of curing the solder resist layer by inductively heating the protective plate by a heat-curing unit having one or more magnetic field generating coils arranged at intervals on one side;
A method for manufacturing a flexible wiring board comprising: The flexible wiring board according to any one of claims 3 to 5, wherein a surface temperature (Ts) of the heat medium in contact with the substrate is 70 ° C <Ts <120 ° C. Method. a. A substrate supply reel for sending out a substrate on which a circuit pattern is formed,
b. A transport unit that transports the substrate placed on the upper surface and transported from the substrate supply reel,
c. An application unit that is provided on the downstream side in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape,
d. A protection tape supply reel that is disposed downstream from the coating unit in the transport direction of the transport unit and that sends out a protective tape stacked on the upper surface of the substrate;
e. The protection tape supply reel is provided on the downstream side in the transport direction of the transport unit with a protection plate on both sides, and the substrate on which the solder resist layer is formed is formed into a roll via the protection tape. Reel to wind,
f. Having at least one heating element buried inside the protection plate or disposed at least on the outer surface side of the protection plate at an interval, heating the protection plate to form the solder resist layer A heat curing unit for drying and curing,
A flexible wiring board manufacturing apparatus comprising: a. A substrate supply reel for sending out a substrate on which a circuit pattern is formed,
b. A transport unit that transports the substrate placed on the upper surface and transported from the substrate supply reel,
c. An application unit that is provided on the downstream side in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape,
d. A protection tape supply reel that is disposed downstream from the coating unit in the transport direction of the transport unit and that sends out a protective tape stacked on the upper surface of the substrate;
e. The protection tape supply reel is provided on the downstream side in the transport direction of the transport unit with a protection plate on both sides, and the substrate on which the solder resist layer is formed is formed into a roll via the protection tape. Reel to wind,
f. A rotation mechanism disposed at both ends of the reel to rotate the reel;
g. A heat-curing unit having one or more magnetic field generating coils arranged at intervals on at least one of the outer surface sides of the protective plate, and inductively heating the protective plate with a magnetic field generated by the magnetic field generating coil,
A flexible wiring board manufacturing apparatus comprising: a. A substrate supply reel for sending out a substrate on which a circuit pattern is formed,
b. A transport unit that transports the substrate placed on the upper surface and transported from the substrate supply reel,
c. An application unit that is provided on the downstream side in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape,
d. The heating unit, which is provided downstream from the coating unit in the transport direction of the transport unit and has a heating medium in contact with the substrate, conducts heat generated by the heating unit to the heating medium. A heating and drying unit for drying the surface of the solder resist layer by contacting the substrate with the heating medium,
e. A protection tape supply reel that is provided downstream from the heating and drying unit in the transport direction of the transport unit and that sends out a protective tape to be stacked on the upper surface of the substrate;
f. The protection tape supply reel is provided on the downstream side in the transport direction of the transport unit with a protection plate on both sides, and the substrate on which the solder resist layer is formed is formed into a roll via the protection tape. Reel to wind,
g. The substrate and the reel around which the protective tape has been wound, a heat-curing unit that performs high-temperature heating to cure the solder resist layer,
A flexible wiring board manufacturing apparatus comprising: a. A substrate supply reel for sending out a substrate on which a circuit pattern is formed,
b. A transport unit that transports the substrate placed on the upper surface and transported from the substrate supply reel,
c. An application unit that is provided on the downstream side in the conveyance direction of the conveyance unit and applies an insulating ink to the upper surface of the substrate to form a solder resist layer in a predetermined shape,
d. The heating unit, which is provided downstream from the coating unit in the transport direction of the transport unit and has a heating medium in contact with the substrate, conducts heat generated by the heating unit to the heating medium. A heating and drying unit for drying the surface of the solder resist layer by contacting the substrate with the heating medium,
e. A protection tape supply reel that is provided downstream from the heating and drying unit in the transport direction of the transport unit and that sends out a protective tape to be stacked on the upper surface of the substrate;
f. The protection tape supply reel is provided on the downstream side in the transport direction of the transport unit with a protection plate on both sides, and the substrate on which the solder resist layer is formed is formed into a roll via the protection tape. Reel to wind,
g. A rotation mechanism disposed at both ends of the reel to rotate the reel;
h. A heat-curing unit having one or more magnetic field generating coils arranged at intervals on at least one of the outer surface sides of the protective plate, and inductively heating the protective plate with a magnetic field generated by the magnetic field generating coil,
A flexible wiring board manufacturing apparatus comprising: 11. An L-shaped rail portion which is provided at both ends in the lateral direction of the upper surface of the heat medium and conveys both ends of the substrate by sandwiching both ends of the substrate in a gap with the heat medium. Flexible wiring board manufacturing equipment. The flexible heating device according to any one of claims 9 to 11, wherein the heating and drying unit includes an external exhaust air intake hole that is disposed above the heating and drying unit and that exhausts air to the outside. Wiring board manufacturing equipment. At least, an application step of applying an insulating ink to the upper surface of the substrate having a circuit pattern formed on the surface to form a solder resist layer in a predetermined shape,
A heat curing step of drying and curing the solder resist layer while winding the substrate on which the solder resist layer is formed into a roll via a protective tape,
A method for manufacturing a flexible wiring board, comprising: The method for manufacturing a flexible wiring board according to claim 13, further comprising a heating and drying step of drying a surface of the solder resist layer between the applying step and the heating and curing step.

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