JPS60192385A - Developing unit for printed circuit board - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

[Detailed Description of the Invention] [Field of Application of the Invention] The present invention provides a developing device in which an atmosphere tank is provided between a developing tank and a washing tank to prevent washing water from mixing with an organic solvent, which has an adverse effect on development. The present invention relates to a development apparatus particularly suitable for developing photoresists for high density and high precision printed circuit boards.

[Background of the invention]

Conventionally, unexposed photoresist on a printed circuit board is developed by spraying an organic solvent on both sides while the printed circuit board is being transported, and immediately washed with water after development.

Water was sprayed onto the circuit board to fix it.

If the time required for washing before development and pre-adhesion is long, the organic solvent on the printed circuit board evaporates and the photoresist dissolved in the organic solvent remains on the printed circuit board. In particular, if photoresist remains on copper that is to be removed by etching in the next step, the copper will remain in that area without being etched, resulting in a so-called short-circuit defect. Therefore, after development, it is necessary to wash the printed circuit board with water while the organic solvent remains on the surface without evaporating, and for this reason, the developing tank and the washing tank cannot be provided with a distance from each other due to the structure. Therefore, in order to immediately wash the circuit board with water after development, conventional developing devices use partition plates between the walls of the developer tank and the washing tank, and provide drain rollers at the outlet of the developer tank and the inlet of the washing tank. By providing a cover on the roller, the structure was such that washing water from the washing tank was prevented from entering the developing tank.

FIG. 1 is a side view of a conventional developing device. A spray developing tank 1 is a device for developing a printed circuit board by spraying an organic solvent onto both sides of a printed circuit board conveyed by a conveyor 5 from a sampler 6, a spray developing tank 2, and a spray rinsing tank 3.
Similar to the spray developing tank 1, the washing spray tank 4 is a device that sprays an organic solvent onto both sides of the printed circuit board 50 from the spray nozzle 6 to further advance development and finish the process. A liquid removal roller 7 is a device for removing and fixing organic solvents with water sprayed from a printed circuit board, and a cover 8 is a roller for removing and fixing organic solvents from a printed circuit board. This is a cover to prevent solvent or water from entering the adjacent tank.

In the developing device having the above structure, when the printed circuit board passes through the drain roller 7, the washing water in the washing spray tank 4 flows through the printed circuit board and into the adjacent spray rinse tank 3. In addition, it is possible to completely prevent the occurrence of a gap between the liquid draining rollers 7 and the splashing of the washing water sprayed from the washing spray tank 4 into the developing tank through the gap. I can't do it. Even if the material and shape of the drain roller 7 and the shape of the cover 8 of the drain roller were modified, this problem could not be solved. If washing water gets mixed into the organic solvent, when developing is performed while spraying the organic solvent in the developing tank, the mixed washing water will be sprayed onto the circuit board and temporarily fixed, causing a negative effect on the development. It has been found that the mixing of washing water into organic solvents must be avoided at all costs. However, if the operation is continued for more than a certain period of time, washing water gets mixed into the developer tank and affects the development, so it is necessary to temporarily stop the operation and remove the washing water mixed into the organic solvent. This has the disadvantage that it poses a problem for driving.

[Purpose of the invention]

An object of the present invention is to prevent washing water from mixing with the organic solvent in the developing tank, and to transport the printed circuit board from the developing tank to the washing tank while the organic solvent on the printed circuit board remains without being volatilized. An object of the present invention is to provide a developing device having a structure.

[Summary of the invention]

The organic solvent used to develop printed circuit boards cannot be mixed with washing water, which has a negative effect on development, so the developing device must have a structure that separates the developing tank from the washing tank.
The organic solvent on the printed circuit board evaporates at the portion where the printed circuit board is separated during transportation, resulting in a problem in which only the dissolved photoresist remains. Therefore, if you keep the organic solvent in a state where it does not volatilize, you can avoid problems like spray treatment.
We thought that this would prevent the organic solvent on the printed circuit board from volatilizing without the problem progressing. Further, by separating the developing section and the washing section, it is possible to prevent washing water from the washing section from entering the developing section.

That is, the present invention is characterized by a printed circuit board developing device in which an atmospheric tank filled with fine particles of an organic solvent for development is provided between a developing tank and a washing tank.

[Embodiments of the invention]

An embodiment of the present invention will be described below with reference to FIG. The developing device of this embodiment is composed of a spray developing tank 1, a spray developing iron tank 2, a spray rinsing tank 3, an organic solvent atmosphere tank 9, a washing spray tank 4, and a conveyor 5. Spray developing tank 1, spray developing tank 2, and spray rinsing tank 3 are each supplied with an organic solvent to a spray nozzle 6 by a pump (not shown), and is sprayed toward a conveyor 5. Further, in the washing spray tank 4, washing water is supplied to a spray nozzle 6 by a pump (not shown), and is sprayed toward the conveyor 5. The organic solvent atmosphere tank 9 is added according to the present invention, and is provided between the spray rinse tank 3 and the washing spray tank 4.
An organic solvent is supplied to the nozzle nozzle 10 by a pump (not shown), and the inside of the organic solvent atmosphere tank 9 is filled with two particles of organic solvent.

Current status of this example @! In the 'Jj' position, while the printed circuit board is being conveyed by the conveyor 5, the spray developing tank 1 and the spray developer tank 1 are loaded.

Spray an organic solvent on both sides of the printed circuit board in the spray rinse tank 3 and perform development I. The printed circuit board is then transported to an organic solvent enclosure 9. The organic solvent atmosphere tank 9 is injected with organic solvent fine particles from the spray nozzle 10, so the tank is filled with organic solvent fine particles. While the organic solvent is passing through the printed circuit board, the organic solvent remains without being volatilized. Because droplets of organic solvent are not forcibly sprayed onto the printed circuit board, development hardly progresses. Therefore, when the printed circuit board leaves the organic solvent atmosphere bath 9, it is left in the same state as when it entered. Then, the printed circuit board is transferred to the washing spray tank 4 and washed with water, so that the organic solvent on the printed circuit board can be washed away while the resist remains dissolved.

Since the organic solvent atmosphere tank 9 is provided, the washing water in the washing spray tank 4 enters the organic solvent atmosphere tank 9, but does not enter the spray rinse tank 3. Organic solvent atmosphere in organic solvent tank 9.

The circulation system is separate from the circulation systems for spray developing tank 1, spray developing tank 2, and spray rinsing tank 3, in order to prevent the washing water mixed into the organic solvent atmosphere tank 9 from being mixed into the organic solvent used for development. Therefore, stable development is possible.

In conventional developing devices, the washing water from the washing tank becomes water droplets and collects in the organic solvent in the developing tank adjacent to the washing tank, and the water content in the organic solvent in the developing tank is also saturated. In the developing device of the invention, water droplets were found in the organic solvent in the developing tank, and the water content was also significantly reduced.

〔Effect of the invention〕

According to the present invention, it is possible to prevent the washing water in the washing tank from mixing with the organic solvent in the developing tank, and to print from the developing tank to the washing tank while the organic solvent on the printed circuit board remains unvolatilized. Since the structure is such that the circuit board can be transported, development can always be carried out under stable development conditions, and defects caused by development can be prevented from occurring.

[Brief explanation of the drawing]

FIG. 1 is a side view showing the structure of a conventional developing device, and FIG. 2 is a side view showing the structure of a securing device which is an embodiment of the present invention. 1... Spray developer tank 2... Spray developer tank 3.
...Spray rinse tank 4...Wash spray tank 5...
Conveyor 6...Spray nozzle 7...Draining roller 8...Cover 9...Atmosphere tank 10...Nod Spray Nozzle Representative Patent Attorney Akio Takahashi No. 2 Z

Claims (1)

[Claims] In a developing device having a developing tank for dissolving and removing unexposed photoresist on a printed circuit board with an organic bath agent and a washing tank for fixing after development, the organic solvent is present between the developing tank and the washing tank. A developing device for a printed circuit board, characterized by being provided with an atmosphere tank filled with fine particles.