JP3341311B2 - Flexible wiring board and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flexible wiring board excellent in component mounting, impedance characteristics, flexibility and the like used for an operation panel and the like of electronic equipment, and a method of manufacturing the same.

[0002]

2. Description of the Related Art A conventional flexible wiring board is formed by attaching a copper foil on a flexible board, leaving a circuit portion by an etching method, and removing other portions to form a conductive circuit, or a silver powder or the like. In general, a conductive circuit is printed on a flexible substrate using a conductive paste obtained by dispersing a conductive powder in a resin varnish.

[0003]

However, in the above-mentioned conventional flexible wiring board, the former has a problem of high cost due to the treatment of waste liquid by etching, environmental problems and the like, and furthermore, bending resistance of the copper foil. There is also a problem that the properties are not sufficient. In the latter case, there is a problem that the bending resistance is sufficient but the wiring resistance is high and soldering is impossible.

The present invention solves such a conventional problem, and includes a flexible wiring board which is excellent in bending resistance including a bent portion of an insulating film, has low wiring resistance, and can be soldered at low cost. It is intended to provide a manufacturing method.

[0005]

SUMMARY OF THE INVENTION The present invention in order to solve the above problems, a printed conductive circuit layer formed by printing a conductive paste to the wiring pattern on the insulating film, the insulating
A metal layer formed by plating on the printed conductive circuit layer excluding the bent portion of the film;
Formed on a portion of the printed conductive circuit layer and the metal layer , excluding at least a soldering land and a connection portion.
And Ca is obtained by the bar coating formed of an insulating layer structure.

[0006]

According to the present invention, the metal layer can be easily soldered by, for example, applying a solder plating or a gold plating on a copper plating, and a waste liquid treatment such as a conventional copper foil etching method is not required. Since the process can be simplified, the flexible wiring board according to the present invention can be provided at a low cost, and the bending resistance is broken by 180 ° several times in the case of the conventional copper foil. Organization the main barrel layer also printed conductive circuit layer broken is not able to break, and metal layers in the bent portion according to the
Since it is not formed, the bending resistance including this portion is extremely good.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS FIGS.
Is a flexible wiring board. According to the figure, reference numeral 2 denotes a printed conductive circuit layer, which is formed on the insulating film 1 by pattern printing or the like. Reference numeral 3 denotes a bulk metal layer formed on the printed conductive circuit layer 2 by plating. Reference numeral 4 denotes an insulating layer, which is formed in a portion surrounding the periphery of the solder land 5a. Reference numeral 5 denotes a solder portion for soldering a chip component 6 and a lead component 7 to a solder land portion 5a formed of bulk metal.

The printed conductive circuit layer 2 is made of an insulating film 1
Polyester resin or epoxy resin with good adhesion to urethane resin or their modified resins, etc.
The bulk metal layer 3 is formed of a conductive paste in which a conductive powder of silver, copper, palladium, or the like is dispersed, and copper, solder, nickel, gold, or the like formed on the printed conductive circuit layer 2 by electroplating or electroless plating. It consists of.
The insulating layer 4 is made of a vinyl chloride resin, a urethane resin, an epoxy resin, or a modified resin thereof, which is flexible and has good adhesion to the insulating film 1. As the insulating film 1, polyimide, polyester, polyetherimide, polyetheretherketone, polysulfone, polyethersulfone, polyphenylenesulfide, or the like is used.

[0009] Then, FIG. 2 (a), (b), the precondition 2
In this figure, only the points different from the prerequisite example 1 in FIG. 1 will be described. The only difference is that the reinforcing plate 8 is formed on the back side of the insulating film 1 so as to be strong against bending of the soldered portion and the like. . As the reinforcing plate 8, a polyester film such as polyethylene terephthalate, an aluminum plate or the like is used.

Further , as shown in a premise example 3 in FIG. 3, a printed conductive circuit layer 9 for jumpers may be formed on the insulating layer 4 .
No. The printed conductive circuit layer 9 for jumpers is formed of the same conductive paste as in the prerequisite example 1 of FIG. 1 having good adhesion to the bulk metal of the lower layer circuit. Also, this jumper mark
Bulk metal layer formed by plating on printed conductive circuit layer 9
May be.

[0011] Then, FIG. 4 is off in accordance with the first aspect of the present invention
And shows a Rekishiburu wiring board, on the assumption Example 1 of FIG. 1
On the other hand, as shown in the figure, the difference is that the bulk metal layer 3 is formed without the bent portion C. With this configuration, it is possible to ensure a better bendability than the premise example 1 of FIG.

Although the insulating layer 4 according to the above description is formed by a printing method, it may be formed by a laminating method of an insulating film .

As described above , the present invention shown in FIG.
Item 1. In the flexible wiring board according to item 1, a printed conductive circuit layer 2 having excellent adhesion and flexibility on the insulating film 1;
A metal layer 3 formed by plating on the printed conductive circuit layer 2 except for the bent portion of the insulating film 1, the insulating fill
The bent portion of the memory 1 on the printed conductive circuit layer 2 and the metal
By providing a flexible insulating layer 4 on the layer 3 at least at a portion other than the soldering land portion 5a, the bent portion
It has better flexibility than the conductive circuit layer formed by the etching method, including the components, and can be soldered by the metal layer 3, and has a low wiring resistance equivalent to that of the conductive circuit formed by the etching method. Thus, the present invention has the effects of simplifying the process compared to the etching method and realizing a low-cost excellent flexible wiring board capable of ascertaining the reasons for effective use of resources.

Next, FIGS. 5 (a) and 5 (b) illustrate a premise example 4. FIG.
Is a view for bright, according to the figure, 15 is patterned by screen printing or the like on and the insulating film 11 is printed conductive circuit layer. 19 is the printed conductive circuit layer 15
It is a bulk metal layer formed by plating. 1
Reference numeral 6 denotes an insulating layer, which is formed by printing on portions other than the connection portion. Connections made of bulk metal as described above
Are those that can be connected soldered to the copper conductor 12 which is covered with a cover coat insulating film 13 except for the solder portion 14 formed by etching.

The printed conductive circuit layer 15 is obtained by dispersing a conductive powder such as silver, copper, or palladium in a polyester resin, an epoxy resin, a urethane resin, or a modified resin thereof having good adhesion to the insulating film 11. The bulk metal layer 19 is formed of a conductive paste by electroplating or electroless plating.
It is a bulk metal such as copper, solder, nickel, and gold formed thereon. The insulating layer 16 is made of a vinyl chloride resin, a urethane resin, an epoxy resin, or a modified resin thereof, which is flexible and has good adhesion to the insulating film 1. Polyimide as the insulating film 11, a polyester, polyetherimide, polyether ether ketone, polysulfone, polyether sulfone, the polyphenylene sulfide or the like is used
Are the same as those in the premise example 1.

Further , as shown in a premise example 5 in FIG. 6 , the bulk metal layer 19a may be formed only on the connection portion where the solder portion 14 is formed .

[0017] Thus, a structure of connecting the those flexible <br/> reluctant wiring board polyimide copper clad laminate comprising a copper conductor 12 in the above precondition 4,5, polyimide copper clad laminate is heat resistant temperature Is high, so that solder connection with components is easy, and since the connection portions on both sides are made of metal, solder connection can be performed, so that connection reliability is excellent, and steps such as heat sealing can be omitted. Further, since the metal layer 9 is formed on the printed conductive circuit layer 15 by plating, the wiring resistance is low, and it is only necessary to partially use the polyimide copper clad board. Therefore, an excellent flexible wiring board at low cost can be realized. Things.

Next, referring to FIG. 7 , according to claim 4 of the present invention .
The flexible wiring board will be described. According to the figure,
21 is an insulating film, 22 is a printed conductive circuit layer formed on the insulating film 21, 23 is a cover coat insulating layer selectively formed on the printed conductive circuit layer 22, 24
Is a bulk metal layer formed on the printed conductive circuit layer 22; 25 is a cover coat insulating layer; 26 is another printed conductive circuit layer formed on the printed conductive circuit layer 22 and the bulk metal layer 24; Other cover coat insulating layer, 28
Is a reinforcing plate bonded to the insulating film 21.

In the flexible wiring board shown in FIG. 1 , the printed conductive circuit layer 22 is a conductive paste (D Toyobo D
X-121H) was screen-printed in a predetermined pattern and then dried at 150 ° C. for 30 minutes. The cover coat insulating layer 23 is made of an insulating resist paste (FC-
30G) was screen printed and dried under the same conditions as the printed conductive circuit layer 22. The bulk metal layer 24 was formed by electroplating copper 15 μm and then electroplating solder 5 μm. further
A cover coat insulating layer 25 is formed, and another printed conductive circuit layer 26 like the printed conductive circuit layer 22 and another cover coat insulating layer 27 like the cover coat insulating layer 23.
Was formed by screen printing to obtain a multilayer wiring. As the reinforcing plate 28, a 1 mm aluminum plate was used.

The printed conductive circuit layer 22 is made of an insulating film.
21 can be selected from a conductive paste in which conductive powders such as silver, copper, and palladium are dispersed in a polyester resin, an epoxy resin, a urethane resin, or a modified resin thereof having good adhesion to the bulk metal layer 24. Is a printed conductive circuit layer 2 formed by electroplating or electroless plating.
2, bulk metal such as copper, solder, nickel, and gold can be selected. The cover coat insulating layers 23, 25 and 27 are made of a rubber-based resin, a vinyl-based resin, a urethane-based resin or an epoxy-based resin, or a modified or mixed resin thereof, which is flexible and has good adhesion to the insulating film 21. It can be selected from those that are the main components. As the insulating film 21, polyimide, polyester, polyetherimide, polyetheretherketone, polysulfone, polyethersulfone, polyphenylenesulfide, or the like can be used.

The above-described structure is the same as that of the insulating film 2.
1, a printed conductive circuit layer 22 having excellent adhesion and flexibility;
A flexible cover coat insulating layers 23 and 25 are formed on the printed conductive circuit layer 22 at a portion (part B) where bending is required without providing a bulk metal layer 24.
Therefore, a part (part B) that requires bendability is included.
It has better flexibility than the conductive circuit layer formed by the etching method, can be soldered on the bulk metal layer 24, and has a low wiring resistance equivalent to that of the conductive circuit formed by the etching method. It is possible to realize a low-cost excellent flexible wiring board that can realize simpler processes and more efficient use of resources than the etching method ,
In addition, the configuration of the multilayer wiring can be easily made .

Next, referring to FIG. 8 , claim 2 of the present invention will be described .
Will be described. According to the drawing, 33 is an insulating film, 34 is a printed conductive circuit on the insulating film 33, 32 is a bulk metal layer formed on the printed conductive circuit 34, 35 is a cover coat insulating layer,
Reference numeral 7 denotes a reinforcing plate sandwiched between insulating films 33. The printed conductive circuit layer 34 is patterned on the insulating film 33 by screen printing or the like.
Is formed by plating on the printed conductive circuit layer 34,
The cover coat insulating layer 35 is formed in a portion other than the connection terminal portion C. The reinforcing plate 37 is formed while bending the insulating film 33 to reinforce the connection terminal portion C.

The printed conductive circuit layer 34 is obtained by dispersing a conductive powder such as silver, copper, or palladium in a polyester resin, an epoxy resin, a urethane resin, or a modified resin thereof having good adhesion to the insulating film 33. The bulk metal layer 32 is formed of a conductive paste by electroplating or electroless plating.
It is a bulk metal such as copper, solder, nickel, and gold formed thereon. The cover coat insulating layer 35 is made of a vinyl chloride resin, a urethane resin, an epoxy resin, or a modified resin thereof having flexibility and good adhesion to the insulating film 33. Insulating film 33
Examples thereof include polyimide, polyester, polyetherimide, polyetheretherketone, polysulfone, polyethersulfone, and polyphenylenesulfide. As the reinforcing plate 37, a polyester film, a phenol laminate, a glass epoxy laminate, an aluminum metal plate, or the like is used.

FIG. 9 shows a specific example in which the ends of the flexible wiring board shown in FIG. 8 are used as connectors, and the ends of the flexible wiring board are soldered to the lands 39 of the printed circuit board 38 with solder 40. is there.

It should be noted, as shown in FIG. 10 (a), (b)
To, a reinforcing plate 37a is formed with solderable metal of aluminum metal plate or the like, Tsu der that the reinforcing plate 37a is also to improve the connection strength with soldering by solder 40 to the land portion 39 of the printed circuit board 38 You may .

As described above, since the flexible wiring board according to the second aspect of the present invention is formed by bending the connection portion C with the reinforcing plate 37 interposed therebetween, the flexible wiring board can be easily mounted on a printed circuit board. Can be provided.

Next, a flexiv according to claim 3 of the present invention.
The wiring board will be described with reference to FIG. According to the drawing, reference numeral 41 denotes an insulating film.
On the printed conductive layer 47 for shielding by screen printing or the like
Is formed, and the printed conductive circuit layer 42 is patterned thereon by screen printing or the like via the insulating layer 44. 43
Is a bulk metal layer formed by plating on the printed conductive circuit layer 42, and furthermore, an insulating layer 44 is formed in a portion surrounding the periphery of the soldering land. Reference numeral 45 denotes a solder portion, and a component 4 is connected to a land portion formed of bulk metal.
6 is to be soldered.

The printed conductive circuit layer 42 and the shielded printed conductive layer 47 are made of an insulating film 41 and an insulating layer 44.
Polyester resin or epoxy resin with good adhesion to urethane resin or their modified resins, etc.
The bulk metal layer 43 is formed of a conductive paste in which a conductive powder of silver, copper, palladium, or the like is dispersed. The bulk metal layer 43 is formed of copper, solder, nickel, gold, or the like formed on the printed conductive circuit layer 42 by electroplating or electroless plating. Is a bulk metal. The insulating layer 44 is made of a vinyl chloride resin, a urethane resin, an epoxy resin, or a modified resin thereof having flexibility and good adhesion to the insulating film 41. As the insulating film 41, polyimide, polyester, polyetherimide, polyetheretherketone, polysulfone, polyethersulfone, polyphenylenesulfide, or the like is used.

As shown in FIG. 12, a reinforcing plate 48 may be formed on the back side of the insulating film 41 so as to be strong against bending at a soldered portion or the like . The reinforcing plate 48 may be made of polyethylene terephthalate or the like. A polyester film, an aluminum plate or the like can be used .

As shown in FIG. 13, a printed conductive circuit layer 49 for a jumper bridging between the bulk metal layers 43 may be formed on the insulating layer 44 .

Further, as shown in FIG. 14 , the bulk metal layer 43 is formed by partial plating except for the bent portion D.
And excellent bendability similar to that shown in FIG. 4 described above.
There be something that can be secured.

As shown in FIG. 15, a shielded printed conductive layer 47a is formed on the insulating film 41 on the opposite side of the insulating film 41 on which the printed conductive circuit layer 42 is formed. It is formed 44
No. Further , a bulk metal layer may be formed on the printed conductive layer for shielding 47 by plating.

As described above, according to the third aspect of the present invention.
Can provide a low-cost flexible wiring board having an excellent shielding function by providing the shielded printed conductive layer 47 or 47a.

Subsequently, a flexi according to claim 5 of the present invention.
The flexible wiring board will be described with reference to FIG. According to FIG.
Reference numeral 1 denotes an insulating film. A printed conductive circuit layer 52 is formed on the insulating film 51, and a cover coat insulating layer 53 is provided on the printed film. 54 is an insulating film 51
Is a printing adhesive material layer formed on the back side of the printing adhesive material layer 55, a printing release material layer formed on the printing adhesive material layer 54,
Reference numeral 56 is a reinforcing plate similarly bonded to the printing adhesive layer 54.

[0035] For the above-described structure, In more detail, the conductive circuit layer 52 work size 500 × 30
A polyester film having a thickness of 0 mm and a thickness of 75 μm (product number: 30) was used as the insulating film 51, and a conductive paste (DX-121H manufactured by Toyobo) was screen-printed in a predetermined pattern, and then dried at 150 ° C. for 30 minutes.
The cover coat insulating layer 53 was screen-printed with an insulating resist paste (XB-803A manufactured by Fujikura Kasei) and dried under the same conditions as the printed conductive circuit layer 52. Next, an adhesive paste (UPA-046 manufactured by Fujikura Kasei) is screen-printed and ultraviolet-cured on the back surface of the film to form an adhesive layer 54, and a release masking paste (TB-3044 manufactured by Three Bond) is screen-printed and ultraviolet-cured. A release material layer 55 was formed. The reinforcing plate 56 is a 1 mm aluminum plate obtained by peeling off the release material layer 55 after processing the outer shape of the flexible wiring board.

The adhesive used for the adhesive layer 54 is a vinyl resin such as vinyl chloride or vinyl acetate, a rubber resin such as chloroprene rubber, nitrile rubber or natural rubber, an acrylic resin or a polyolefin resin. , Urethane-based, polyester-based, epoxy-based, and silicone-based resins, or their copolymerized resins and blended resins, depending on the required adhesive strength. Solvent drying, thermosetting, ultraviolet curing, etc. Select the drying equipment according to the type of drying. The release material of the release material layer 55 is not necessary for the product performance as a flexible wiring board and is a sub-material, so that any material can be used as long as it can provide an appropriate peeling force.

The reinforcing plate 56 includes a soft plate such as polyester and a hard plate such as glass epoxy or aluminum plate.
Generally, in the case of a flexible board, a reinforcing board coated with an adhesive in advance may be attached before the external processing of the flexible wiring board, and the external processing of the flexible wiring board and the reinforcing board may be performed collectively. The post-release material may be attached instead of printing.

Although the above description has been made with reference to the flexible wiring board using the printed conductive circuit layer 52, even if the conductive circuit layer is the most commonly used copper foil etched circuit wiring , or the double-sided wiring It may be a board or a multilayer wiring board .

As described above, the structure according to claim 5 of the present invention.
In this case, the adhesive material layer and the release material layer can be collectively printed on the front or back surface of the flexible wiring board with the print work size, so not only the workability is extremely good but also the adhesive material and the release material are in a paste state. There is no wrinkle problem because the material is not pasted almost completely because the material is lost because it is screen printed. Furthermore, although a printing mask is required, preliminary external processing of the double-sided pressure-sensitive adhesive sheet and a mold for it are not required. It has an effect that it does not adhere to the mold, and therefore frequent mold cleaning is not required.

The printing of the adhesive and the release material should be performed by continuously connecting the respective printing machines for the adhesive and the release material, regardless of whether the insulating film is in the form of a roll or a sheet. Thus, it is possible to improve productivity and prevent troubles due to the adhesiveness of the adhesive.

Next, according to claims 6 and 7 of the present invention,
A flexible wiring board according to the present invention will be described with reference to FIG. According to the drawing, reference numeral 61 denotes an insulating film, and a printed conductive circuit layer 62 is formed on the insulating film 61;
Reference numeral 3 denotes a cover coat insulating layer formed so that an end of the printed conductive circuit layer 62 is exposed.

Incidentally, a bulk metal layer may be formed on the exposed portion of the printed conductive circuit layer 62 by plating. Reference numeral 64a denotes a soft reinforcing material layer formed at the end on the back surface side of the insulating film 61, and 64b denotes a soft reinforcing material layer 6
This is a hard reinforcing material layer formed on 4a, which is provided with a connector portion by forming the end of the flexible wiring board as described above.

[0043] For the above-described structure, In more detail, printed conductive circuit layer 62 work size 500 ×
A conductive paste (DX-121H manufactured by Toyobo Co., Ltd.) was screen-printed in a predetermined pattern using a 300 mm thick 75 μm polyester film (30 products) as an insulating film 61 and then dried at 150 ° C. for 30 minutes. The cover coat insulating layer 63 was screen-printed with an insulating resist paste (XB-803A manufactured by Fujikura Kasei) and dried under the same conditions as the printed conductive circuit layer 62. Next, a soft reinforcing material paste (EP-1 manufactured by Cemedine) is applied to the end of the back surface of the film.
70 / diluted solvent isophorone 5% by weight) is screen printed and cured at 150 ° C. for 30 minutes to form a soft reinforcing material layer 64a. The soft reinforcing material layer 64a is superimposed on the hard reinforcing material layer (EP-170, 47 manufactured by Cemedine). 0.5% by weight / E
P-171, 47.5% by weight / dilute solvent isophorone 5% by weight) is screen-printed and cured at 150 ° C. for 30 minutes to form a hard reinforcing material layer 64b, and the total material thickness of the soft reinforcing material layer 64a and the hard reinforcing material layer 64b Was set to 200 μm.

[0044] Then, as a result of connector insertion tested for flexible wiring board was attached adhesive 20μm with polyethylene terephthalate film 180μm used conventional flexible wiring board having the above structure as a reinforcing plate, a flexible wiring board according to the prior art Is 20
The printed conductive circuit layer 62 was shaved 50 times, whereas the printed wiring circuit layer 62 provided with the reinforcing material layers 64a and 64b according to the present invention was shaved 50 times.

The reinforcing material is a vinyl resin such as vinyl chloride, a rubber resin such as chloroprene rubber, nitrile rubber, or natural rubber, an acrylic resin, a polyolefin resin, a urethane resin, a polyester resin, an epoxy resin, or a silicone resin. What is necessary is just to select from resin, their copolymer system resin, and blend resin according to required intensity | strength.

[0046] Further, in the above has been described a flexible wiring board using the printed conductive circuit layer 62, the conductive circuit layer is also the most commonly used are copper etched circuit wiring, also double-sided wiring board Alternatively, it may be a multilayer wiring board .

As described above, claims 6 and 7 of the present invention
According to the configuration described in Item 7 , since the reinforcing material layers 64a and 64b can be collectively printed and formed in a predetermined place on the flexible wiring board in a print work size, not only the workability is extremely good, but also the reinforcing material is Since the paste state is screen-printed, there is no material loss, and there is no wrinkle problem because the paste is not attached. Furthermore, adhesive coating of the reinforcing sheet of printing masks necessary things, a preliminary outline processing and molds therefor required, without adhesive glue when flexible wiring board outline processing adheres to the mold, thus <br / > Frequent mold cleaning is not necessary.

Further, when the printing is made twice and the first printing is made of a soft material and the second printing is made of a hard material, the insertion / extraction of the connector at the end is greatly improved.

Next, a flexiv according to claim 8 of the present invention.
The wiring board will be described with reference to FIG. According to the drawing, reference numeral 71 denotes an insulating film.
A printed conductive circuit layer 72 on which a wiring pattern is formed by screen printing using a conductive paste, and a bulk metal layer 73 formed on the printed conductive circuit layer 72 by a plating method,
At least a portion of the bulk metal layer 73 other than the through hole land portion E and the external connection portion F is provided with a cover coat insulating layer 74.
Is formed by screen printing with a flexible insulating paste, and a printed conductive circuit layer 75 for connecting the through hole land portion is further formed by screen printing with a conductive paste,
A bulk metal layer 76 is formed on the printed conductive circuit layer 75 by a plating method, and a cover coat insulating layer 77 is formed by screen printing on at least a portion of the bulk metal layer 76 excluding the external connection portion F. A reinforcing plate 78 is mounted on the back surface.

The above structure will be described in more detail. The printed conductive circuit layers 72 and 75 are screen printed with silver paste (DX-121H manufactured by Toyobo Co., Ltd.).
C. and dried for 30 minutes. The printed conductive circuit layers 72 and 75 are made of polyester resin, epoxy resin, urethane resin, a modified resin thereof, or the like having good adhesion to the insulating film 71 or the cover coat insulating layer 74 .
A conductive paste in which a conductive powder such as copper or palladium is dispersed can be used. Bulk metal layer 73 and 76 printed conductive circuit layer by electroplating or electroless plating 72 and
75 , which is a bulk metal such as copper, solder, nickel, and gold.

In the above configuration, the bulk metal layer 73
Is 15 μm electrolytic copper plating, and the bulk metal layer 76 is 1 μm.
After plating with 0 μm electrolytic copper, 5 μm solder plating was performed. The cover coat insulating layers 74 and 77 are made by screen-printing a flexible insulating ink (Shikoku Chemicals FC-30G) and drying at 150 ° C. for 30 minutes, and have flexibility and an insulating film 71 and bulk metal layers 73 and 76. It is mainly composed of a rubber-based resin, a vinyl-based resin, a urethane-based resin or an epoxy-based resin, or a modified or mixed resin thereof, having good adhesion to the resin. The insulating film 71 is a polyester film, polyimide,
It is also possible to use polyetherimide, polyetheretherketone, polysulfone, polyethersulfone, polyphenylenesulfide and the like.

According to the above configuration , the conductive circuit layer has more flexibility than the conductive circuit layer formed by the etching method, can be soldered on the bulk metal layer 73, and is further formed by the etching method. It is possible to provide a flexible wiring board having an excellent through- hole land portion at a low cost, which can realize a low wiring resistance equivalent to that of a conductive circuit, can further simplify the process as compared with the etching method, and can effectively use resources. .

Subsequently, a flexi according to claim 9 of the present invention.
The method of manufacturing the bull wiring board will be described with reference to FIGS.

According to the figure, 81 is an insulating film, 82
Is a printed conductive circuit layer, 83 is a bulk metal layer, 84 is an insulating layer, and 85 is a through-hole. Each manufacturing process will be described below in order.

FIG. 19A shows a step of forming a pattern of a printed conductive circuit layer 82 on the insulating film 81 by screen printing, and FIG. 19B shows a printing step of performing printing. FIG. 19C shows a step of pattern-forming the printed conductive circuit layer 82a on the back surface of the insulating film 81 by screen printing, and FIG. 19D shows a printing step of performing printing. FIG. 19E shows a step of forming a through hole 85 at a predetermined position, and FIG. 19F shows a step of applying a conductive paste to the through hole 85 to form a printed conductive circuit layer 82b. FIG. 19 (g) shows a step of forming the bulk metal layer 83 by plating, and FIG. 19 (h) shows a step of forming a cover coat insulating layer at least at a portion excluding a soldering land / connection portion.

The printed conductive circuit layers 82 to 82b are made of a polyester resin, an epoxy resin, a urethane resin, a modified resin thereof, or the like having good adhesion to the insulating film 81, and a conductive powder such as silver, copper, or palladium. The bulk metal layer 83 is formed of a dispersed conductive paste, and is a bulk metal such as copper, solder, nickel, or gold formed on the printed conductive circuit layer 82 by electroplating or electroless plating. The insulating layer 84 is made of a vinyl chloride resin, a urethane resin, an epoxy resin, or a modified resin thereof having flexibility and good adhesion to the insulating film 81. As the insulating film 81, polyimide, polyester, polyetherimide, polyetheretherketone, polysulfone, polyethersulfone, polyphenylenesulfide, or the like is used.

Next, a flexi according to claim 10 of the present invention.
The method of manufacturing the bull wiring board will be described with reference to FIGS. Note that the same parts as those in the configuration shown in FIG.

[0058] FIG. (A) is a step of drilling a through-hole bore 85 at a predetermined position of the insulating film 81, FIG. 20
(B) is Ru step der patterning a printed conductive circuit layer 82 by screen printing on the insulating film 81. this
A conductive paste for forming the printed conductive circuit layer 82
Enters into the through-hole 85 as shown in FIG.
Embed. FIG. 20C shows a printing step for performing printing. FIG. 20D shows a step of patterning the printed conductive circuit layer 82 a by screen printing on the back surface of the insulating film 81.
Then, the inside of the through hole 85 is connected. And FIG.
0 (e) is a step of performing printing, and is a step of forming a bulk metal layer 83 by plating in FIG.
FIG. 20 (g) shows a step of forming a cover coat insulating layer 84 at least in a portion excluding a soldering land / connection portion.

In addition to the above, it is also possible to form a reinforcing plate such as a polyester film, a phenol laminate, a glass epoxy laminate, a metal plate or the like in a portion requiring reinforcement, and furthermore, a printed conductive circuit on the insulating layer. By forming the layers, double-sided flexible wiring boards having multilayer wiring can be manufactured.

The ninth and the first aspects of the present invention described above.
According to the method for manufacturing a flexible printed circuit board according to the first embodiment, a printed conductive circuit layer 82 having excellent adhesion and flexibility by a screen printing method excellent in mass productivity on the insulating film 81;
By forming a bulk metal layer 83 formed by plating on the printed conductive circuit layer and a flexible insulating layer 84 at least in a portion excluding a soldering land and a connection portion, the insulating layer 84 is formed by a conventional etching method. It has better flexibility than the conductive circuit layer, allows soldering on the bulk metal layer 83, and can realize a low wiring resistance equivalent to a conductive circuit formed by an etching method ,
Also, an excellent low-cost flexible wiring board which can simplify the process and effectively use resources as compared with the conventional etching method and drawing method can be realized.

[0061]

As described above, the present invention provides a printed conductive circuit layer in which a wiring pattern is formed by printing a conductive paste on an insulating film, and a printed conductive circuit layer excluding a bent portion of the insulating film. A metal layer formed by plating on the printed conductive circuit layer and a bent portion of the insulating film.
Preliminary on said metal layer, at least the soldering consist land connection cover coating insulating layer formed on the portion except for the portion, excellent bending resistance, the wiring resistance is low, solderable low cost flexible wiring board Is made possible.

[Brief description of the drawings]

FIG. 1 (a) shows a flexible wiring board as a premise example 1 ;
Oblique plan view (b) the A2 part sectional side view of an essential portion shown in FIG. 1 A1 part sectional side view of an essential portion shown in (a) (c) the FIGS. 1 (a)

FIG. 2A is a cross-sectional side view of a main part of a flexible wiring board as a prerequisite example 2; FIG. 2b is a flexible wiring of another configuration as the prerequisite example 2;
Side sectional view of main part of plate

FIG. 3 is a side sectional view of a flexible wiring board as a premise example 3;

FIG. 4 is a side sectional view of the flexible wiring board according to claim 1 of the present invention .

5A is a top view of a flexible wiring board as a premise example 4, and FIG.

FIG. 6 is a side sectional view of a flexible wiring board as a premise example 5;

FIG. 7 is a side sectional view of a flexible wiring board according to claim 4 of the present invention .

FIG. 8 is a perspective view of a flexible wiring board according to claim 2 of the present invention .

FIG. 9 is a sectional side view of a main part of a specific example in which the end of the flexible wiring board shown in FIG. 8 is used as a connector;

FIG. 10 (a) Flexib according to claim 2 of the present invention
Side cross-sectional view showing another embodiment of the Le wiring board (b) the top view

FIG. 11 is a side sectional view of a flexible wiring board according to claim 3 of the present invention .

FIG. 12 is a side sectional view when the reinforcing plate is formed .

FIG. 13 is a side sectional view of the case where the printed conductive circuit layer for the jumper is provided .

FIG. 14 is a side cross-sectional view having the bent portion .

FIG. 15 is a flexible wiring according to claim 3 of the present invention .
Side sectional view showing another form of the plate

FIG. 16 is a side sectional view of a flexible wiring board according to claim 5 of the present invention .

FIG. 17 shows a frame according to claims 6 and 7 of the present invention .
Cross-sectional side view of the kibble wiring board

FIG. 18 is a side sectional view of a flexible wiring board according to claim 8 of the present invention .

19 (a) to 19 (h) show a frame according to claim 9 of the present invention.
Figure it illustrates the preparation of Kishiburu wiring board

20 (a) to 20 (g) are drawings according to claim 10 of the present invention.
The figure explaining the manufacturing method of a flexible wiring board

[Explanation of symbols]

1,11,21,41,51,61,71,81 Insulating film 2,15,22,42,52,62,72,82 Printed conductive circuit layer 3,19,24,43,73,83 Bulk metal layer 4, 16, 25, 44, 84 Insulating layer 12 Copper conductor 23, 53, 63, 74 Cover coat insulating layer 28, 37 Reinforcement plate 47 Printing conductive layer for shielding 54 Printing adhesive layer 55 Printing release material layer 64a Soft reinforcing material Layer 64b Hard reinforcement layer 85 Through hole

────────────────────────────────────────────────── ─── Continuation of the front page (72) Inventor Futa Matsui 1006 Kazuma Kadoma, Kadoma, Osaka Prefecture Matsushita Electric Industrial Co., Ltd. (56) References JP-A-3-34493 (JP, A) JP-A-56- 142698 (JP, A) JP-A-56-90590 (JP, A) JP-A-61-179593 (JP, A) JP-A-4-145690 (JP, A) JP-A-3-141683 (JP, A) JP-A-64-90587 (JP, A) JP-A-2-54274 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05K 3/24 H05K 1/02 H05K 3/12 H05K 3/28 H05K 3/40

Claims (10)

(57) [Claims] 1. A print conductive circuit layer formed on the insulating film, and a metal layer formed by plating the printed conductive circuit layer excluding the bent portion of the insulating film, before
Above and before the printed conductive circuit layer at the bent portion of the insulating film
Serial on the metal layer, a flexible wiring board comprising a cover coating insulating layer formed in a portion except at least soldering land-connection. 2. A printed conductive circuit layer formed on an insulating film, a metal layer formed by plating on the printed conductive circuit layer, and a cover formed on at least a portion of the metal layer excluding connection terminal portions. The coat consisting of a coat insulating layer
A flexible wiring board, wherein the connection terminal portion is formed to be bent with a reinforcing plate interposed therebetween. 3. A printed conductive circuit layer formed on an insulating film, a bulk metal layer formed by plating on the printed conductive circuit layer, and a film or an insulating layer on the side opposite to the printed conductive circuit layer. It said printing conductive circuitry layer lower or shield for printing conductive layer formed on either the top of the flexible wiring board comprising at least covercoat insulating layer formed on the part excluding the soldering rad connecting portion via. 4. A printed conductive circuit formed on an insulating film.
Road layer, and formed by plating on the printed conductive circuit layer
Metal layer and at least the connection terminals of this metal layer.
Excluding the cover coat insulating layer
A flexible wiring board, further comprising a printed conductive circuit layer formed on the cover coat insulating layer.
Board. 5. A dielectric film conductive circuit layer formed on at least the soldering land portion of the conductive circuit layer, the flexible wiring board to form a cover coating insulating layer in a portion except for the connecting portions, the front surface or the back surface of A flexible wiring board comprising a pressure-sensitive adhesive layer or a release material layer formed by superposing the pressure-sensitive adhesive layer on a pressure-sensitive adhesive layer at a desired place. 6. A conductive circuit layer formed on an insulating film.
And at least a soldering land portion of the conductive circuit layer ,
Flexible with a cover coat insulating layer formed on the part except the connecting part
In the case of shivable wiring boards, a reinforcing plate
Off Rekishiburu wiring board you wherein the printed forming the reinforcing material layer by screen printing as. 7. A flexible wiring board according to claim 6 wherein configured in a reinforcing material layer and the soft stiffener layer and the hard stiffener layer. 8. A printed conductive circuit layer formed on an insulating film, and a metal layer formed on the printed conductive circuit layer by a plating method, and at least a portion of the metal layer excluding a through hole land portion and an external connection portion. A flexible wiring board comprising: a cover coat insulating layer; a printed conductive circuit layer for connecting throughhole lands; and another metal layer formed on the printed conductive circuit layer by plating. 9. A printed conductive circuit layer is formed by printing a predetermined pattern of a conductive paste on both sides of an insulating film by a screen printing method and printing the conductive paste.
A hole is formed in a predetermined position to form a through-hole layer made of a conductive paste, then a bulk metal layer is formed by plating on the printed conductive circuit layer, and a cover coat is formed on at least a portion excluding a solder land and a connection portion. A method for manufacturing a flexible wiring board, comprising forming an insulating layer. 10. A hole is formed at a predetermined position of a through hole layer on an insulating film, and a predetermined pattern including the through hole is printed on both surfaces of the insulating film by a screen printing method and printed. To form a printed conductive circuit layer, a bulk metal layer is formed by plating on the printed conductive circuit layer, and a cover coat insulating layer is formed at least in a portion excluding a solder land and a connection portion. A method for producing a flexible wiring board, which is a feature of the present invention.