JP3168739B2 - Transfer method and transfer device for printed wiring board - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method and an apparatus for transporting printed wiring boards used in various electronic devices such as personal computers and word processors.

[0002]

2. Description of the Related Art In recent years, printed wiring boards, which are widely used in various electronic devices and the like, have become increasingly dense and densely wired and surface-mounted on electronic components as electronic devices have become lighter, thinner, shorter and more multifunctional. The lands on which conductive patterns and electronic components are to be formed on insulating substrates are becoming increasingly narrower in pitch, thinner and smaller in diameter, preventing solder from adhering to unnecessary parts, protecting the conductive patterns from oxidation, maintaining insulation, Solder resists and roadmaps formed on printed wiring boards for the purpose of improving solderability, etc., also require high resolution and high positional accuracy. It is replacing the law.

[0003] However, the photographic development method is generally more complicated than the screen printing method and the productivity is low, so that the cost tends to be high. In order to solve this problem, spray coating, electrostatic coating, roll coater, and curtain coater have been studied as methods for applying solder resist ink for photo development, especially in order to improve productivity in the solder resist process. A roll coater method and a curtain coater method, which have high application efficiency of a solder resist ink for photographic development, have attracted attention.

[0004] A method of transporting a printed wiring board in the formation of a solder resist for photo development in the manufacture of a conventional printed wiring board will be described below.

FIG. 3A is a conceptual view of a conventional solder resist ink coating apparatus for developing a photo on a printed wiring board.
FIG. 3B is a perspective view showing a transport state of a conventional printed wiring board before application of a solder resist ink for photo development, and FIG.
(C) is a perspective view showing a state of conveyance of a conventional printed wiring board after application of a solder resist ink for photo development.

In FIG. 3, 11 is a heating section, 12a is a section for applying a solder resist ink for photo development, 12b is a solder resist ink for photo development, 13 is a printed wiring board,
14a is a conveying section of a heating section, 14b is a conveying section before application of the solder resist ink for photo development, 14c is a conveying section after application of the solder resist ink for photo development, 14d is a conveying section of a touch drying section, and 15 is a finger. It is a touch drying part.

The operation of the method for forming a solder resist on a printed wiring board configured as described above will be described below.

First, an etching resist is formed on a copper-clad laminate (not shown) cut to a predetermined size by a photo-developing method or a screen printing method, and then etched using a solution such as cupric chloride. Is performed to form a conductor pattern on the insulating substrate, and the etching resist is peeled off.

Next, the printed wiring board 13 having the conductor pattern formed on the insulating substrate is transported to a solder resist ink coating device for photographic development as shown in FIG. 3A, and is shown in FIG. 3B. The heating unit 11 heats the printed wiring board surface temperature to about 60 ° C. (hereinafter, referred to as preheating), and the conveying unit 14a causes the V-shape of the front conveying unit 14b of the photographic developing solder resist coating device. It is transported to the mold conveyor. The printed wiring board 13 conveyed to the application part 12a of the solder resist ink 12b for photo development is printed on the printed wiring board 1 by the film-shaped solder resist ink 12b falling vertically above the printed wiring board 13.
3 progresses, the solder resist ink 12b for photo development is applied with a predetermined thickness, and as shown in FIG.
4c, it is conveyed to the touch drying unit 15 by the conveying unit 14d.

[0010] After the solder resist ink 12b for photo-development applied by hot air or the like is touch-dried, a mask film for forming a solder resist is brought into close contact and exposed to ultraviolet light, and the unexposed portions of the solder-resist ink 12b for photo-development are removed. It is developed and removed with a predetermined developing solution, and cured again with hot air or the like to form a solder resist having a predetermined shape on the printed wiring board 13.

[0011]

However, in the above-mentioned conventional configuration, the V-shaped conveyor of the pre-transport portion 14b for applying the solder resist ink for photographic development has a thin print, particularly corresponding to a reduction in the size and weight of electronic equipment. Wiring board 13
In FIG. 3, the printed wiring board 13 softened by heating as shown in FIG. 3 (b) is significantly bent, and it becomes difficult to apply the solder resist ink 12b for photo development in a horizontal state. However, it is not possible to ensure a predetermined uniform thickness of the solder resist ink 12b.

Further, the solder resist ink 12b for photographic development is applied in a state where the printed wiring board 13 is significantly bent, and after the solder resist ink 12b for photographic development is applied, the solder is transferred to the V-shaped conveyor of the transfer section 14c, and then flattened. When the printed wiring board 13 is transported to the transport section 14d of the soft touch drying section, the front end of the printed circuit board 13 in the bent state is
There is a problem that the process yield and productivity of the printed wiring board manufacturing process are reduced, for example, the contact / collision with the flat conveyer d and the derailment / stagnation from the conveyer.

In some cases, both sides of the photo-resist solder resist ink 12b are simultaneously exposed as a means of improving productivity. However, the application of the photo-resist solder resist ink 12b to the second surface of the printed wiring board 13 may be performed. Front transport unit 1
In the V-shaped conveyor 4b, the solder resist ink 12 for photographic development is applied to the first surface by preheating similarly to the first surface.
As shown in FIG. 3B, the printed wiring board 13 coated with b is remarkably bent and comes into contact with the solder resist ink 12b for photographic development on the first surface softened by preheating.
The printed wiring board 1 causes defects such as damage and peeling.
(3) There is also a problem in that the appearance of defects is induced, and there is a danger of generating a solder ball in the electronic component mounting process in the production of electronic equipment, or causing a defect in an electronic circuit such as a solder show. Had.

The present invention solves the above-mentioned conventional problems, and in particular, makes uniform the thickness of the solder resist on a printed wiring board having a relatively small thickness, and significantly improves the production yield and productivity in the solder resist forming step. It is another object of the present invention to provide a method and a device for transporting a printed wiring board, which can improve the reliability of an electronic device.

[0015]

In order to achieve the above object, a method for transporting a printed wiring board according to the present invention is directed to a method for transporting a printed wiring board on which a conductor pattern is formed by heated air blown from a lower portion of the printed wiring board. The printed wiring board is inclined and floated in a direction perpendicular to the transport direction, and the printed wiring board is moved by an inclined rotating body that comes into contact with the end of the printed wiring board on the inclined side.

[0016]

According to this configuration, the solder resist forming area of the printed wiring board can be kept in a non-contact state during the preheating, the application of the solder resist ink for photo development, and the transport to the touch drying section.

[0017]

(Embodiment 1) An embodiment of the present invention will be described below with reference to the drawings.

FIG. 1A is a conceptual view of a printed wiring board conveying device according to a first embodiment of the present invention, and FIG.
1 shows a front conveyance section and a rear conveyance section for application of a solder resist ink for photo development in an embodiment of the present invention.

In FIG. 1, reference numeral 21 denotes a heating section; 22a, an application section of a solder resist ink for photo development; 22b, a solder resist ink for photo development; 23, a printed wiring board;
24a is a conveying section before applying the solder resist ink for photo development, 24b is a conveying section after applying the solder resist ink for photo developing, 25 is a nozzle for ejecting gas, 26 is a rotating body such as a belt roller for conveying, and 27 is Heated air.

The operation of the method of transporting a printed wiring board configured as described above will be described with reference to FIG.

First, a copper-clad laminate (not shown) cut to a predetermined size is subjected to through-hole processing and copper plating, and then an etching resist is formed by a photo-developing method or a screen printing method. Etching is performed using a solution such as cupric chloride to form a conductor pattern on the insulating substrate, and the etching resist is peeled off to form a conductor pattern on the insulating substrate. Thus, the printed wiring board 23 is obtained.

Next, as shown in FIG.
The printed wiring board 23 conveyed to the printed wiring board 23 is inclined and floated by the pressure-controlled and heated air 27 ejected from a plurality of nozzles 25 arranged at the lower part of the conveying section, and the printed wiring board 23 is simultaneously inclined. The inclined lower end contacts a rotating body 26 such as an inclined / rotating belt roller, and the surface temperature of the printed wiring board 23 is reduced to 40 to 6 while being inclined / floating.
The temperature is raised to 0 ° C., preheated, and transported sequentially. By this preheating, the insulating substrate and the conductor pattern constituting the printed wiring board 23 are heated, the compatibility with the solder resist ink 22b for photographic development to be applied is improved, and the generation of pinholes and bubbles is suppressed.

Next, the printed wiring board 23 is accelerated while maintaining the inclined and floating state in the pre-transport portion 24b before the application of the solder resist ink 22b for photo development, and the solder resist ink 22b for photo development drops in a film form. After passing through the application section 22a at a speed of about 70 to 90 m / min, the solder resist ink 22b for photographic development is applied on the printed wiring board 23 to a predetermined thickness.

Thereafter, the printed wiring board 23 is conveyed to the rear conveying portion 24b of the solder resist ink 22b for photographic development and is decelerated at the same time as the front conveying portion 22a. 27, the solvent contained in the solder resist ink for photo development 22b is volatilized, and the solder resist ink for photo development 22
The touch drying of b starts. Conventionally, touch drying has been performed at a temperature of 60 to 80 ° C. for about 15 to 30 minutes in a hot air circulation tank or the like, but the touch drying time is 5 to 10 minutes due to transportation by the heated gas 27. It became possible to shorten.

The printed wiring board 23 having the photo-resisting solder resist ink 22b film formed on the first surface is coated on the second surface of the printed wiring board 23 in the same manner as the first surface. A film is formed.

Next, a mask film for forming a solder resist is adhered and vacuum-adsorbed to the film surface of the solder resist ink for photo-development 22b which has been applied to the printed wiring board 23 and dried by touch. Approximately 500-70 light by ultraviolet light having a wavelength suitable for polymerization
Exposure is performed at a value of 0 mJ / cm ² , and the unexposed portion is developed and removed with a developing solution containing sodium carbonate as a main component. The soldering resist is formed on the printed wiring board 23 by strengthening the adhesive force under the condition (1).

In the printed wiring board 23 according to the embodiment of the present invention, no coating unevenness and poor conveyance are not observed, and the solder resist on the first surface of the printed wiring board 23 on which the solder resist is formed is scratched or peeled off. Could not be admitted.

(Embodiment 2) Hereinafter, a second embodiment of the present invention will be described with reference to the drawings.

FIG. 2A is a conceptual diagram of a printed wiring board transport device according to a second embodiment of the present invention, and FIG.
FIG. 2 is a cross-sectional view showing the concept of the state of the printed wiring board immediately before and at the time of applying the solder resist ink for photo development in an embodiment of the present invention. FIG. It is sectional drawing which shows the concept of the state of a wiring board.

In FIG. 2, 21 is a heating section, 22a is a section for applying a solder resist ink for photo development, 22b is a solder resist ink for photo development, 23 is a printed wiring board,
24a is a conveying section before applying the solder resist ink for photo development, 24b is a conveying section after applying the solder resist ink for photo developing, 25 is a nozzle for ejecting gas, 26 is a rotating body such as a belt roller for conveying, and 27 is The heated air is the same as the configuration shown in FIG.

The difference from the configuration shown in FIG.
And a heating element 2 above the plane parallel to the transport direction of the rear transport section 24b.
8 and the point that inclined rotating bodies 26 and 26a are provided on both sides in the transport direction of the last part of the front transport section 24a.

The operation of the method of transporting a printed wiring board configured as described above will be described below.

First, a conductive pattern is formed on an insulating substrate by a method similar to the conventional method, and a printed wiring board 23 is obtained.

Next, as shown in FIG.
The printed wiring board 23 conveyed to the printer is inclined and floated by pressure-controlled and heated air 27 ejected from a plurality of nozzles 25 disposed at the lower part of the conveying section, and the inclined printed wiring board 23 is inclined. The lower end portion contacts a rotating body 26 such as an inclined / rotating belt roller, and the printed wiring board 23 is conveyed while being inclined / floating.

At the same time, the surface temperature of the printed wiring board 23 is instantaneously raised and preheated to 40 to 60 ° C. by the heating element 28 installed above the plane parallel to the conveying direction, and the printed wiring board 23 is printed. The plate 23 is sequentially conveyed. By this preheating, the insulating substrate and the conductor pattern constituting the printed wiring board 23 are heated, the compatibility with the solder resist ink 22b for photographic development to be applied is improved, and the generation of pinholes and bubbles is suppressed.

Next, the printed wiring board 23 is formed by a plurality of independent inclined rotating bodies 26 and 26a linearly arranged on both sides in the transport direction of the last portion of the transport section 24b before application of the solder resist ink 22b for photo development. As shown in FIG. 2B, the solder resist ink 2 for photographic development is curved and accelerated in a convex shape while maintaining a floating state from the plane in the transport direction.
2b is applied at a speed of about 70 to 90
After passing through the printed wiring board 23 at a predetermined thickness, the solder resist ink 22b for photo-development is applied on the printed wiring board 23 at m / min.

Thereafter, the printed wiring board 23 is conveyed to the rear conveying portion 24b of the solder resist ink 22b for photographic development and is decelerated at the same time as shown in FIG. 2 (c). While floating, the solvent contained in the solder resist ink 22b for photographic development is volatilized by the heated air 27, and at the same time, a heating element such as a high-pressure mercury lamp and an infrared or far-infrared heater provided above the plane parallel to the transport direction. Exposure to the atmosphere in a heated state by 28 causes the touch-drying of the solder resist ink for photo development 22b to start in the transport state. Conventionally, a temperature of 60-
Touch drying was performed at 80 ° C. for a time period of about 15 to 30 minutes. However, touch drying became almost feasible within the transport time due to the heated gas 27 and the heating element 28.

The printed wiring board 23 having the first surface coated with the photo-resist solder resist ink 22b is coated on the second surface of the printed wiring board 23 in the same manner as the first surface. A film is formed.

Next, a mask film for forming a solder resist is adhered and vacuum-adsorbed to the film surface of the solder resist ink 22b for photo-development applied to the printed wiring board 23 and dried by touching to form a solder resist ink 22b for photo-development. Approximately 500-70 light by ultraviolet light having a wavelength suitable for polymerization
Exposure is performed at a value of 0 mJ / cm ² , and the unexposed portion is developed and removed with a developing solution containing sodium carbonate as a main component. If necessary, a temperature of 130 to 160 ° C. and a time of about 30 to 60 minutes are used in a hot air circulation tank or the like. The soldering resist is formed on the printed wiring board 23 by strengthening the adhesive force under the condition (1).

As described above, the heating element 28 is provided above the plane parallel to the transport direction of the front transport section 24a and the rear transport section 24b.
The inclined rotating body 2 is provided on both sides in the transport direction
6 and 26a, the printed wiring board 23 that is curved and accelerated in a convex shape becomes almost horizontal at the application part 22a of the solder resist ink 22b for photo development, and the coating unevenness is remarkably improved, No occurrence of transport failure was observed even in the thin printed wiring board 23, and no scratches or peeling of the solder resist on the first surface of the printed wiring board 23 on which the solder resist was formed could be recognized.

In the first and second embodiments of the present invention, the printed wiring board 23 is a double-sided printed wiring board. However, the printed wiring board 23 may be a single-sided printed wiring board, a multilayer printed wiring board, or a photo-developing solder. Resist ink 2
2b is an alkali developing type, but may be a solvent developing type. In the first and second embodiments of the present invention, the solder resist forming process using the solder resist ink 22b for photo development is used as the manufacturing process of the printed wiring board. However, the process may be a pattern forming process or a road map forming process. Needless to say.

[0042]

As described above, according to the present invention, a printed wiring board on which a conductor pattern is formed is inclined / floated in a direction perpendicular to the conveying direction by gas ejected from a lower part of the printed wiring board, and the end of the printed wiring board on the inclined side is provided. By moving the printed wiring board with the inclined rotating body that comes in contact with the device, the yield of the printed wiring board manufacturing process can be significantly increased, such as simplification of the preheating device and touch drying device and prevention of conveyance failure, and the reliability of electronic equipment can be improved. Thus, it is possible to realize a printed wiring board that improves the performance.

[Brief description of the drawings]

FIG. 1A is a conceptual diagram of a printed wiring board transfer apparatus according to a first embodiment of the present invention; FIG. 1B is a front transfer section and a rear transfer section for applying a solder resist ink for photo development in the first embodiment; Perspective view showing the part

FIG. 2 (a) is a conceptual view of a printed wiring board transport device according to a second embodiment of the present invention. FIG. 2 (b) is a print just before and at the time of applying a solder resist ink for photo development in the second embodiment. Schematic diagram showing the concept of the state of the wiring board (c) is a schematic diagram similarly showing the concept of the state of the printed wiring board after the application of a solder resist ink for photo development.

3A is a conceptual diagram of a conventional solder resist ink coating device for photo-developing a printed wiring board of a conventional example. FIG. 3B shows a transport state of the conventional printed wiring board before coating the solder resist ink for photo-development. Perspective view (c) is a perspective view showing a transport state of a conventional printed wiring board after application of a solder resist ink for photo development.

[Explanation of symbols]

21 Heating Section 22a Solder Resist Ink for Photo Development 22b Solder Resist Ink for Photo Development 23 Printed Wiring Board 24a Pre-Transport Section for Solder Resist Ink Application 24b Photo Conveyance Section for Solder Resist Ink for Photo Development 25 Nozzle 26 Rotating body 27 Heated air

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-63-74816 (JP, A) JP-A-62-140955 (JP, A) JP-A-4-280748 (JP, A) JP-A 54-1979 25546 (JP, A) JP-A-64-36041 (JP, A) JP-A-2-8121 (JP, A) JP-A-57-47032 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) H05K 13/02

Claims (8)

(57) [Claims] 1. A printed wiring board on which a conductive pattern is formed is tilted and floated in a direction perpendicular to a conveying direction by heated air ejected from a lower portion of the printed wiring board, and the printed wiring board comes into contact with an end of the printed wiring board on an inclined side. A method of transporting a printed wiring board that moves the printed wiring board with a rotating body. 2. The method according to claim 1 , wherein the heating is performed from an upper portion in the transport direction.
The method of transporting the printed wiring board. 3. A sandwiching the printed wiring board side end portion in the conveyance end portion in an inclined rotary body, transporting the printed wiring board according to the printed wiring board in claim 1 to float and movement in the convex state with respect to the conveying surface Method. 4. A printed wiring board comprising: a plurality of independent nozzle groups for ejecting heated air from a lower direction in a transport direction; and a plurality of independent inclined rotating bodies linearly arranged at least on one side in a transport direction. Transport device. 5. The printed wiring board transfer device according to claim 4 , further comprising a heating element provided above the plane parallel to the transfer direction. 6. The method of claim 4 comprising a plurality of independent inclined rotating body arranged in a straight line in the conveying direction on both sides of the conveying end portion
The printed wiring board conveying device as described in the above. 7. The printed wiring board conveying device according to claim 4, wherein the plurality of independent inclined rotating bodies are belt rollers. 8. The printed wiring board conveying device according to claim 4, wherein the plurality of independent inclined rotating bodies are metal rollers.