JPH08148804A - Forming method of electric circuit - Google Patents

Abstract

PURPOSE: To provide a forming method of an electric circuit which forms precise electric continuity circuits on the surface and inside all kinds of structures. CONSTITUTION: Conducting metal particles 4a are mixed in mixing material 2 of abhesive agent, coating material or liquid resin, etc. The mixing material 2 is spread on base material 1 by printing, spraying, etc. After curing, the surface is irradiated with a laser beam. Thereby the conducting metal particles 4a are collected or fused, and an electric conductor circuit 3 is formed on the base material 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for producing an electric circuit for forming a precise electric conduction circuit on the surface and inside of any structure such as metal, resin, ceramics, wood, soil and paper.

[0002]

2. Description of the Related Art A technique for directly forming an electric circuit on the surface of a molded product regardless of the material of the base material, the shape of the molded product, the roughness of the surface of the molded product, etc. has not been proposed so far.

As a technique close to this, after flattening the surface of a molded product to some extent, an insulating film is attached by sputtering or vapor deposition, and a conductive metal such as copper is attached thereon by plating or the like, and then a resist is formed. There is a method of forming an electric circuit on the surface of a molded product by applying, and exposing and etching a pattern (this is referred to as Prior Art 1). In addition, at the time of molding, a method of forming a film having a circuit pattern by transfer or in-mold molding (this is referred to as prior art 2),
There is a method of forming a circuit pattern by two-color molding of a material with plating and a material without plating (this is referred to as prior art 3).

[0004]

However, in the above-mentioned prior art 1, the molding method itself is very expensive. It cannot be applied when the molded product has a complicated curved surface. Since it is necessary to use chemicals and clean,
There was a problem that the material of the base material was limited.

Further, the above-mentioned conventional technique 2 and conventional technique 3
However, the production method itself is very expensive and the cost is high. Further, as the products have become lighter, thinner, shorter and smaller, and the circuit line width has become as fine as several tens of μm or less, the conventional techniques 2 and 3 have a problem that such fine processing cannot be supported.

The present invention was devised to solve the above-mentioned problems, and an object thereof is a method for producing an electric circuit capable of finely processing a circuit line width while responding to lighter, thinner, shorter, smaller products and lower costs. To provide.

[0007]

In order to solve the above-mentioned problems, the method for producing an electric circuit according to claim 1 of the present invention comprises:
Mix conductive metal particles into adhesive, paint or liquid resin,
These adhesives, paints or liquid resins are applied onto the base material by printing or spraying, and by irradiation with a laser beam after curing, the conductive metal particles are aggregated or fused to electrically conduct onto the base material. It forms a circuit.

In the method for producing an electric circuit according to the second aspect of the present invention, after the adhesive material is applied on the base material by printing or spraying, the conductive metal particles are applied on the adhesive material. By applying and irradiating laser light after curing the adhesive,
The conductive metal particles are aggregated or fused to form an electric conduction circuit on the base material.

According to a third aspect of the present invention, there is provided a method for producing an electric circuit, wherein a capsule in which conductive metal particles are covered with a non-conductive thin film is mixed into a resin material, and the capsule is molded with the resin material. By irradiating the surface of the molded product with laser light, the non-conductive thin film of the capsule is peeled off and the conductive metal particles are collected or fused to form an electric conduction circuit.

According to a fourth aspect of the present invention, in a method for producing an electric circuit, a capsule in which conductive metal particles are covered with a non-conductive thin film is mixed into a resin material, and the capsule is molded with the resin material. By irradiating the molded product with laser light to form a through hole, the inner peripheral surface of this through hole is
The non-conductive thin film of the capsule is peeled off to collect or fuse the conductive metal particles to form an electric conduction path, and the electric conduction path connects the electric conduction circuits formed on the front surface and the back surface of the molded product. To do.

[0011]

The operation of the method for producing an electric circuit according to claim 1 will be described.

By mixing conductive metal particles in an adhesive, paint or liquid resin, applying the adhesive, paint or liquid resin on a base material by printing or spraying, and irradiating laser light after curing. The conductive metal particles in the irradiated portion are aggregated or fused to form an electric conduction circuit on the base material.

As a result, a precise electric conduction circuit can be quickly and inexpensively formed on the surface of any structure made of metal, resin, ceramic, wood, paper or the like. It is also possible that the surface of the structure is a complicated three-dimensional curved surface or rough surface.

The operation of the method for producing an electric circuit according to claim 2 will be described.

After the adhesive material is applied on the base material by printing or spraying, the conductive metal particles are applied on the adhesive material, and the adhesive metal is irradiated with laser light to cure the conductive metal particles. Are assembled or fused to form an electric conduction circuit on the base material.

As a result, a precise electric conduction circuit can be quickly and inexpensively formed on the surface of any structure made of metal, resin, ceramic, wood, paper or the like. It is also possible that the surface of the structure is a complicated three-dimensional curved surface or rough surface.

The operation of the method for producing an electric circuit according to claim 3 will be described.

A capsule in which conductive metal particles are covered with a non-conductive thin film is mixed in a resin material, and after molding with this resin material, the surface of the molded product is irradiated with laser light, whereby the non-conductor of the capsule is formed. The thin film is peeled off to collect or fuse the conductive metal particles to form an electric conduction circuit.

As a result, it is possible to easily and inexpensively form a direct and fine electric conduction circuit on a circuit board or a cabinet body having a complicated three-dimensional shape.

The operation of the method for producing an electric circuit according to claim 3 will be described.

By mixing a capsule in which conductive metal particles are covered with a non-conductive thin film into a resin material and molding the resin material, the molded product is irradiated with laser light to form a through hole. On the inner peripheral surface of the through hole, the non-conductive thin film of the capsule is peeled off to collect or fuse the conductive metal particles to form an electric conduction path, which is formed on the front and back surfaces of the molded product. Connect the electrical continuity circuit.

As a result, it becomes possible to connect the electric conduction circuits formed on the front surface and the back surface of the molded product by a simple method of forming a through hole. In addition, it is possible to easily and inexpensively create a direct and fine electric conduction circuit on a circuit board or a cabinet body having a complicated three-dimensional shape.

[0023]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1 is a perspective view of a molded product showing an embodiment corresponding to claims 1 and 2 of the present invention.
It shows an example of a case where a cabinet body, a chassis, a mechanical structure, etc. are formed.

In the figure, reference numeral 1 is a base material (molded product) for forming an electric circuit, and any material such as a metal plate, a resin plate, glass, ceramics, wood and paper can be used. Further, the shape is not limited to the flat plate shape, and the surface may be a complicated three-dimensional shape such as an uneven curved surface.
Reference numeral 2 is an admixture applied on the base material 1 by printing or spraying, a mixed material made of a paint or a liquid resin having adhesiveness, and a capsule member 4 made of conductive metal particles 4a (described later). ) Is mixed. Also, reference numeral 3
Is an electric conduction circuit formed in an arbitrary shape by irradiation with laser light.

As shown in FIG. 2, the capsule member 4 contains conductive metal particles 4a such as gold, aluminum, copper, solder, tin, lead, nickel and carbon, and a non-conductive thin film 4b.
The structure is covered with. Conductive metal particles 4a are several tens of μ
The non-conductive thin film 4b, which is fine particles of m or less, is a thin film of several μm or less.

Next, a method (corresponding to claim 1) for producing an electric circuit having the above structure will be described.

First, the conductive metal particles 4a are replaced with the non-conductive thin film 4b.
The capsule member 4 coated with is mixed with the admixture 2 made of an adhesive, paint or liquid resin. Next, this mixed material 2
Is applied or adhered onto the base material 1 by printing, spraying, injection molding, compression molding or the like to adhere and cure.
After that, an excimer laser (excime laser) is applied to the surface of the applied mixed material 2 through a pattern mask matching the circuit pattern.
r laser).

By this ablation process of the excimer laser, the organic substance of the mixed material 2, that is, the adhesive or the like and the non-conductive thin film 4b of the capsule member 4 are scattered to expose the conductive metal particles 4a. Then, the exposed conductive metal particles 4a are brought into close contact (that is, aggregated or fused), so that the surface of the base material 1 (specifically, the surface to which the mixing material 2 is applied).
The electric conduction circuit 3 having an arbitrary shape is formed in the.

In order to secure the conductivity of the electric conduction circuit 3 (that is, in order to reduce the conduction resistance), the surface of the electric conduction circuit 3 may be coated with solder. In addition to the excimer laser, a YAG laser, a carbon dioxide gas laser, and other heat rays can be used to create a circuit pattern in a single writing with the beam.

According to this production method, a precise electric conduction circuit can be produced on the surface of any structure made of metal, resin, ceramic, wood, paper or the like. Further, even if the surface of the structure is a complicated three-dimensional curved surface or a rough surface, it is possible to create an electric conduction circuit. Furthermore, without being affected by thermal contraction or thermal expansion, it is simple, reliable and inexpensive,
Moreover, the circuit pattern can be created with high accuracy.

Next, another method (corresponding to claim 2) for producing an electric circuit having the structure shown in FIG. 1 will be described.

First, an adhesive layer (corresponding to the mixed material 2) made of an adhesive, a paint or a liquid resin in which the capsule member 4 is not mixed is applied onto the base material 1 by printing, spraying, etc., and before being hardened. The capsule member 4 is applied to and cured. After that, the surface of the adhesive layer coated with the capsule member 4 is irradiated with an excimer laser through a pattern mask matched to the circuit pattern.

By the excimer laser ablation process, the organic material of the adhesive layer and the non-conductive thin film 4b of the capsule member 4 are scattered to expose the conductive metal particles 4a.
Then, the exposed conductive metal particles 4a are brought into close contact (that is, aggregated or fused), so that the surface of the base material 1 (specifically, the surface coated with the adhesive layer) has an electrically conductive circuit of an arbitrary shape. 3 is formed.

The electric conduction circuit 3 may also be coated with solder on its surface in order to ensure the conductivity (that is, to reduce the conductive resistance). In addition to the excimer laser, a YAG laser, a carbon dioxide gas laser, and other heat rays can be used to create a circuit pattern in a single writing with the beam.

According to this production method, a precise electric conduction circuit can be produced on the surface of any structure made of metal, resin, ceramic, wood, paper or the like. Further, even if the surface of the structure is a complicated three-dimensional curved surface or a rough surface, it is possible to create an electric conduction circuit. Furthermore, without being affected by thermal contraction or thermal expansion, it is simple, reliable and inexpensive,
Moreover, the circuit pattern can be created with high accuracy.

Further, in each of the above-mentioned manufacturing methods, the encapsulating member 4 in which the conductive metal particles 4a are covered with the non-conductive thin film 4b is used, but this is a conductive metal that is easily oxidized, such as iron or copper. This is to prevent the oxidation of aluminum, silver, etc., and since there is no fear of oxidation with solder, Pb-Sn, gold, etc., this non-conductive thin film 4b is unnecessary. That is, it is possible to directly mix the conductive metal particles 4a with the mixing material 2 or apply it to the adhesive layer.

FIG. 3 is a perspective view including a partial cross section of a molded product showing an embodiment corresponding to claim 3 of the present invention, and in the case of molding a case body, a cabinet body, a chassis, a mechanical structure and the like. Shows an example.

In the figure, reference numeral 11 is a base material (molded product) for forming an electric circuit, and its shape is not limited to a flat plate shape, and its surface is a complicated three-dimensional shape such as an uneven curved surface. Good. Further, reference numeral 4 is a capsule member 4 made of conductive metal particles 4a and the like mixed in the molded product 11.
Further, reference numeral 13 is an electric conduction circuit formed in an arbitrary shape by irradiation with laser light.

As shown in FIG. 2, the capsule member 4 contains conductive metal particles 4a such as gold, aluminum, copper, solder, tin, lead, nickel and carbon, and a non-conductive thin film 4b.
The structure is covered with. Conductive metal particles 4a are several tens of μ
The non-conductive thin film 4b, which is fine particles of m or less, is a thin film of several μm or less.

Next, a method (corresponding to claim 3) for producing an electric circuit having the above structure will be described.

First, the conductive metal particles 4a are replaced with the non-conductive thin film 4b.
The capsule member 4 coated with is mixed with the resin material 11a, and this is injected into the mold by a molding machine to mold the molded product 11 having the shape shown in FIG. 3, for example. Next, this molded product 11
In order to form the electric conduction circuit 13 on the front surface (or the back surface) of the above, the circuit forming portion is subjected to surface irradiation or scan irradiation with an excimer laser, a YAG laser, or another laser for peeling the resin.

As a result, in the case of an excimer laser, for example, the resin material 11a and the nonconductive thin film 4b of the capsule member 4 in the irradiated portion are scattered by ablation processing, and the conductive metal particles 4a are exposed. Then, the exposed conductive metal particles 4a are brought into close contact (that is, aggregated or fused), so that the electrical conduction circuit 13 having an arbitrary shape is formed on the front surface (or the back surface) of the molded product 11.

When the conductive metal particles 4a are solder, they are melt-bonded by laser heat to form a good conductor circuit. Also,
Even in the case of copper particles or the like, when a higher-quality good conductor is required, the entire molded product 11 is dip-dipped and the electric conduction circuit 13 is covered with solder to obtain a high-quality good conductor. be able to.

Further, when the electric conduction circuits 13 are formed on both the front and back surfaces of the molded product 11 by such a manufacturing method, both electric conduction circuits 13 are formed by through holes which will be described later.
Can be connected (corresponding to claim 4).

That is, after the electric conduction circuits 13 are formed on both the front and back surfaces of the molded product 11 by the above-described manufacturing method, spots of excimer laser or the like are again applied to the circuit forming portion from the front surface or the back surface of the molded product 11 to pass through. Open hole 15. Also at this time, as in the case described above, the resin material 1 of the irradiated portion (that is, the inner peripheral surface of the through hole 15)
1a and the non-conductive thin film 4b of the capsule member 4 are scattered by the ablation process, and the conductive metal particles 4a are exposed. Then, the exposed conductive metal particles 4a are closely attached (that is, aggregated or fused), so that the through hole 15 is formed.
An electric conduction circuit 13a is formed on the inner peripheral surface of the electric conduction circuit 13a, and the electric conduction circuit 13a connects the electric conduction circuits 13 on both front and back surfaces.

According to such a manufacturing method, the circuit of various three-dimensional and complicated patterns can be surely and inexpensively manufactured with high precision by only applying the laser beam, and the molded product 11 can be manufactured. Electric conduction circuit 13 on both front and back sides
Can be electrically connected.

FIG. 4 shows an application example of the method for producing the electric circuit shown in FIG.

That is, the method for producing an electric circuit according to the present invention is applied to electrically connect an electronic component insert-molded in a molded product.

In portable OA equipment, communication equipment, electronic toys, electronic teaching materials, etc., from the viewpoints of lightness, thinness, shortness, low cost, waterproofing and safety of electronic parts, molding of electronic parts such as a case body and a cabinet body is performed. It is required to be embedded in the product as a unit. As a method of embedding an electronic component in a molded product, an integral molding method or a method of inserting the circuit board itself has been attempted, but in any case, a fine movement is caused by a difference in expansion coefficient or a fine movement of the electronic component due to resin pressure. The connection part is broken. In addition, it has not been put to practical use at present because it cannot be applied when the molded product has a complicated three-dimensional curved surface. By applying the method for producing an electric circuit according to the present invention, all such problems can be solved.

An application example of the method for producing an electric circuit according to the present invention will be described below.

In the figure, reference numeral 21 is a base material (molded product) for forming an electric circuit, and its shape is not limited to a flat plate shape, and its surface is a complicated three-dimensional shape such as an uneven curved surface. Good. Further, reference numerals 26 and 27 denote electronic parts (for example, IC chips and resistors, etc.) inserted inside the molded product 21.
Capacitors etc.). Further, reference numeral 4 is a capsule member 4 made of conductive metal particles 4a and the like mixed in the molded product 21.
Is. Further, reference numeral 23 is an electric conduction circuit formed on the surface of the molded product 21 by surface irradiation or scan irradiation of laser light, and reference numeral 23a is an electric conduction circuit reaching the electronic parts 26, 27 formed by spot irradiation of laser light. Is.

As shown in FIG. 2, the capsule member 4 contains conductive metal particles 4a such as gold, aluminum, copper, solder, tin, lead, nickel and carbon, and a non-conductive thin film 4b.
The structure is covered with. Conductive metal particles 4a are several tens of μ
The non-conductive thin film 4b, which is fine particles of m or less, is a thin film of several μm or less. The melting point of the non-conductive thin film 4b is set higher than the melting point of the base material that is the molded product 21.

Next, a method for producing an electric circuit having the above structure will be described.

First, the conductive metal particles 4a are replaced with the non-conductive thin film 4b.
The capsule member 4 coated with is mixed in the resin material 21a. On the other hand, an electronic component such as an IC chip 26 and a resistor 27 are supported at a predetermined position in a mold, and the resin material 21a is injected and injected into the mold. However, in addition to injection molding, RIM molding and cast molding are also possible.

Next, when the resin hardens and cools, the molded product 21 is taken out of the mold and the process of molding the circuit pattern is started.

In the circuit pattern molding step, first, the circuit forming portion of the molded product 21 is irradiated with an excimer laser or a yag laser according to the line width.

In the case of an excimer laser, when a necessary portion is collectively surface-irradiated, the resin material 21a in the irradiated portion is
Only the thickness corresponding to the irradiation time (for example, surface resin of 1 to 2 μm by irradiation for about 5 seconds) is scattered by the ablation process. At this time, at the same time, the non-conductive thin film 4b of the capsule member 4 is also scattered by the ablation process,
The conductive metal particles 4a are exposed. Then, the exposed conductive metal particles 4a are brought into close contact (that is, aggregated or fused), so that an electrically conductive circuit 23 having an arbitrary shape is formed on the surface of the molded product 21.

After this, the electronic parts 26 inside the molded product 21,
Move to 27 connection process.

Since the electronic components 26 and 27 are set at the predetermined positions of the mold, the positions of the connecting portions 26a and 27a are clear in advance.

Therefore, in the wiring process of electronic parts, an excimer laser (or a yag laser) is placed at a position to be connected.
The holes 25 are formed by spot irradiation for a period of time for reaching the depth of the connection portions 26a, 27a. Also at this time, as in the case described above, the resin material 21a in the irradiated portion (that is, the inner peripheral surface of the hole 25) and the non-conductive thin film 4b of the capsule member 4 in this portion are scattered by the ablation process, and the conductivity is reduced. The metal particles 4a are exposed. Then, the exposed conductive metal particles 4a are brought into close contact (that is, gathered or fused) to form an electric conduction circuit 23a on the inner peripheral surface of the hole 25, and the electric conduction circuit 23a forms an electric conduction circuit on the surface. 23 and the electronic components 26 and 27 are connected.

In order to improve the conduction, solder is used for the conductive metal particles 4a, or the molded product 2 after processing is used.
1 by soldering the whole, electrical conduction circuit 23,
23a is covered with solder and can be a good conductor.

According to such a manufacturing method, the molded product 21
Since it is possible to perform microfabrication by laser irradiation in a completely stable state, the circuit of various three-dimensional and complicated patterns can be reliably, inexpensively, and highly enhanced without being affected by pressure, temperature, expansion, etc. during molding. It can be created with precision.

[0064]

The method for producing an electric circuit according to claim 1 of the present invention comprises mixing conductive metal particles in an adhesive, a paint or a liquid resin, and applying the adhesive, paint or liquid resin on a base material. By applying by printing or spraying, and irradiating with laser light after curing, the conductive metal particles in the irradiated portion are aggregated or fused to form an electric conduction circuit on the base material. A precise electric conduction circuit can be quickly and inexpensively formed on the surface of any structure made of metal, resin, ceramic, wood, paper or the like. Further, even if the surface of the structure is a complicated three-dimensional curved surface or rough surface, a precise electric conduction circuit can be created.

In the method for producing an electric circuit according to the second aspect of the present invention, after the adhesive material is applied on the base material by printing or spraying, the conductive metal particles are applied on the adhesive material. Then, by irradiating a laser beam after the adhesive is cured, the conductive metal particles are aggregated or fused to form an electric conduction circuit on the base material, so that metal, resin, ceramic, wood, paper, etc. On the surface of any structure formed by
Precise electrical conduction circuits can be created quickly and at low cost. Also,
Even if the surface of the structure is a complicated three-dimensional curved surface or a rough surface, a precise electric conduction circuit can be created.

According to a third aspect of the present invention, in the method for producing an electric circuit, a capsule in which conductive metal particles are covered with a non-conductive thin film is mixed into a resin material, the resin material is molded, and then the molding is performed. By irradiating the surface of the product with a laser beam, the non-conductive thin film of the capsule is peeled off and the conductive metal particles are aggregated or fused to form an electric conduction circuit, so that a complicated three-dimensional shape is formed. It is possible to easily and inexpensively create a direct and fine electric conduction circuit on the circuit board, the cabinet body, or the like.

According to a fourth aspect of the present invention, in a method for producing an electric circuit, a capsule in which conductive metal particles are covered with a non-conductive thin film is mixed into a resin material, and the resin material is molded. By forming a through hole by irradiating light, the non-conductive thin film of the capsule is peeled off on the inner peripheral surface of the through hole to collect or fuse the conductive metal particles to form an electrical conduction path. Since the electric conduction paths are formed to connect the electric conduction circuits formed on the front and back surfaces of the molded product, the electric conduction circuits formed on the front and back surfaces of the molded product can be simply formed by forming through holes. Can be connected in any way. In addition, a direct and fine electric conduction circuit can be easily and inexpensively formed on a circuit board or a cabinet body having a complicated three-dimensional shape.

[Brief description of drawings]

FIG. 1 is a perspective view showing an example of a molded product having an electric circuit formed on its surface by a method for forming an electric circuit according to the present invention.

FIG. 2 is a cross-sectional view showing the structure of a capsule member mixed with an adhesive or resin.

FIG. 3 is a perspective view including a partial cross section showing an example of a molded product having an electric circuit formed on its surface by the electric circuit forming method according to the present invention.

FIG. 4 is a perspective view including a partial cross section showing an example of a molded product having an electric circuit formed on its surface by the method for forming an electric circuit according to the present invention.

[Explanation of symbols]

 1,11,21 Molded product (base material) 2 Mixed material 3,13,13a, 23,23a Electric conduction circuit 4 Capsule member 4a Conductive metal particles 4b Non-conductive thin film 15 Through hole

Claims (4)

[Claims] 1. A conductive metal particle is mixed in an adhesive, paint or liquid resin, and the adhesive, paint or liquid resin is applied onto a base material by printing or spraying, and after curing, laser light is irradiated. By so doing, the conductive metal particles are aggregated or fused to each other to form an electrical conduction circuit on the base material. 2. A conductive material is applied onto a base material by printing or spraying, conductive metal particles are applied onto the adhesive material, and a laser beam is irradiated after the adhesive is hardened to obtain the conductive material. A method for producing an electric circuit, characterized in that an electrically conductive circuit is formed on the base material by concentrating or fusing the conductive metal particles. 3. A capsule in which conductive metal particles are covered with a non-conductive thin film is mixed in a resin material, the resin material is molded, and then the surface of the molded product is irradiated with laser light, whereby A method for producing an electric circuit, characterized in that an electrically conductive circuit is formed by peeling off a non-conductive thin film and concentrating or fusing the conductive metal particles. 4. By mixing a capsule in which conductive metal particles are covered with a non-conductive thin film into a resin material, molding the resin material, and irradiating the molded product with a laser beam to form a through hole. , An electrically conductive path is formed on the inner peripheral surface of the through hole by peeling off the non-conductive thin film of the capsule to collect or fuse the conductive metal particles, and the electrically conductive path forms a surface of the molded article, and A method for producing an electric circuit, comprising connecting an electric conduction circuit formed on a back surface.