阅读说明：本技术 一种改善印制电路板背钻孔阻焊冒油的方法 (Method for improving solder resist bleeding of back drilling hole of printed circuit board ) 是由 刘光丽 洪翠荣 于 2021-06-02 设计创作，主要内容包括：本发明提供一种改善印制电路板背钻孔阻焊冒油的方法,通过选择塞孔油墨从背钻对应的背面进行塞孔作业,控制塞孔后到印面油停留时间,印刷面油先印背钻对应的背面,再印刷背钻面,在工程处理资料时,将背钻面对应的位置在资料上掏一个比背钻直径单边小的开窗点,通过曝光、背钻面朝下显影、显影时关闭强风吹干,并进行光固化,能够解决印制电路板背钻孔阻焊冒油,使其保持印制电路板良好的外观及可焊性,提升了印制电路板的良率,降低了印制电路板的制造成本。(The invention provides a method for improving solder mask bleeding of a back drilling hole of a printed circuit board, which comprises the steps of selecting plug hole ink to carry out plug hole operation from the back side corresponding to a back drill, controlling the retention time of the plug hole ink to a printing surface ink, printing the printing surface ink on the back side corresponding to the back drill, then printing a back drilling surface, digging a windowing point with the diameter smaller than the single side of the back drill on the data at the position corresponding to the back drilling surface when processing the data in engineering, developing the back drilling surface downwards through exposure, closing strong wind during development, drying by blowing, and carrying out photocuring.)

1. A method for improving solder resist bleeding of a back drilling hole of a printed circuit board is characterized by comprising the following steps:

s1, preparing hole plugging ink: mixing the curing agent and the main agent, and stirring for 15-30 min;

s2, preparing the face oil: mixing a curing agent and a main agent, adding 10-30ml of a diluent, stirring for 15-30min, measuring the viscosity of the uniformly stirred surface oil, and controlling the viscosity to be 140 dpa.s;

s3, plate preparation: passing the printed circuit board to be processed through a board grinding machine, wherein the board grinding speed is 2.5-3m/min, and the board grinding drying temperature is 85-95 ℃;

s4, solder mask plug hole: carrying out hole plugging operation on the hole plugging ink from the back side corresponding to the back drill, and just enabling the ink to just emerge from the back drill corresponding side after hole plugging;

s5, printing face oil: printing surface oil on the plate with qualified plug hole within 15min, printing the back surface corresponding to the back drill on the printing surface oil, printing the back drill surface, and standing the inserting frame for 15-30min after printing;

s6, pre-baking: pre-baking at 72-75 deg.C for 40-45min

S7, data optimization: when the engineering data is manufactured, a windowing point which is 4-8mil smaller than the single side of the back drill diameter is dug on the data at the position corresponding to the back drill surface;

s8, exposure: taking data through a DI machine, positioning and exposing, and exposing 10-13 grids of a ruler;

s9, developing: developing the unexposed position of the plate by sodium carbonate liquid with the concentration of 0.8-1.2%, wherein the developing speed is 3-3.5m/min, and blowing and drying by strong wind during developing;

s10, QC test: inspecting the appearance of the plate;

s11, photocuring: directly carrying out full-plate photocuring on the qualified plate, wherein an exposure ruler has 10-13 grids during photocuring;

s12, thermal curing: the curing parameters were as specified at 80 ℃ 60min +110 ℃ 30min +150 ℃ 60 min.

2. The method for improving solder mask bleeding of the back drilling hole of the printed circuit board as claimed in claim 1, wherein: the proportion of the pore-plugging ink curing agent to the main agent is 25%: 75 percent.

3. The method for improving solder mask bleeding of the back drilling hole of the printed circuit board as claimed in claim 1, wherein: the viscosity of the surface oil is controlled at 120 dpa.s.

4. The method for improving solder mask bleeding of the back drilling hole of the printed circuit board as claimed in claim 1, wherein: the printed circuit board is designed with a back drill, the back drill position needs to be welded and plugged, the back drill surface of the printed circuit board passes through a volcanic ash plate grinding machine downwards, the plate grinding speed is 2.8m/min, and the plate grinding drying temperature is 90 ℃.

5. The method for improving solder mask bleeding of the back drilling hole of the printed circuit board as claimed in claim 1, wherein: and (3) plugging holes of the solder mask from the back side corresponding to the back drill, printing surface oil on the qualified board of the plugged holes within 15min, printing the back side corresponding to the back drill by the printing surface oil, and then printing the back drill side.

6. The method for improving solder mask bleeding of the back drilling hole of the printed circuit board as claimed in claim 1, wherein: when the engineering data is manufactured, a windowing point which is 6mil smaller than the single side of the back drill diameter is dug on the data at the position corresponding to the back drill surface.

7. The method for improving solder mask bleeding of the back drilling hole of the printed circuit board as claimed in claim 1, wherein: the exposure ruler has 12 grids during exposure.

8. The method for improving solder mask bleeding of the back drilling hole of the printed circuit board as claimed in claim 1, wherein: the back drilling surface of the printed circuit board is downward during development, the concentration of the sodium carbonate liquid medicine is 1%, the development speed is 3.2m/min, and strong wind is turned off during development for drying.

9. The method for improving solder mask bleeding of the back drilling hole of the printed circuit board as claimed in claim 1, wherein: the photocuring exposure ruler has 12 grids.

Technical Field

The invention relates to the field of printed circuit board production, in particular to a method for improving solder resist bleeding of a back drilling hole of a printed circuit board.

Background

With the high-speed development of the electronic industry, higher requirements are put forward for printed circuit boards called electronic aircraft carriers, particularly for some boards with special requirements on signal transmission, back drilling design modes are generally adopted for via holes, and simultaneously via holes corresponding to back drilling of the boards require hole plugging treatment, in the manufacturing process of the prior art, because the hole after back drilling is larger than the aperture of the via hole at the remaining position, a step is formed at the intersection position of the back drilling and the via hole, a step is formed in the hole plugging process, a cavity is formed at the intersection position of the back drilling and the via hole when hole plugging gas residue back drilling and the via hole, air hidden at the intersection position of the back drilling and the via hole in the hole expands due to heat when ink is cured by baking the board, so that oil bleeding is reduced, generally, but the method still cannot completely solve the problem, and still easily causes oil bleeding, so that the yield of the printed circuit boards is seriously influenced, the number of defective products is increased, and the manufacturing cost of the printed circuit board is seriously influenced.

Disclosure of Invention

The present invention is directed to solving at least one of the problems of the prior art. Therefore, the method for improving the solder resist bleeding of the back drilling hole of the printed circuit board can solve the problem of solder resist bleeding of the back drilling hole of the printed circuit board, keep the good appearance and solderability of the printed circuit board, improve the yield of the printed circuit board and reduce the manufacturing cost of the printed circuit board.

The method for manufacturing the printed circuit sheet through the solder mask comprises the following steps of:

s1, preparing hole plugging ink: mixing the curing agent and the main agent, and stirring for 15-30 min;

s2, preparing the face oil: mixing a curing agent and a main agent, adding 10-30ml of a diluent, stirring for 15-30min, measuring the viscosity of the uniformly stirred surface oil, and controlling the viscosity to be 140 dpa.s;

s3, plate preparation: passing the printed circuit board to be processed through a volcanic ash plate grinding machine, wherein the plate grinding speed is 2.5-3m/min, and the plate grinding drying temperature is 85-95 ℃;

s4, solder mask plug hole: carrying out hole plugging operation on the hole plugging ink from the back side corresponding to the back drill, and just enabling the ink to just emerge from the back drill corresponding side after hole plugging;

s5, printing face oil: printing surface oil on the plate with qualified plug hole within 15min, printing the back surface corresponding to the back drill on the printing surface oil, printing the back drill surface, and standing the inserting frame for 15-30min after printing;

s6, pre-baking: pre-baking at 72-75 deg.C for 40-45 min;

s7, data optimization: when the engineering data is manufactured, a windowing point which is 4-8mil smaller than the single side of the back drill diameter is dug on the data at the position corresponding to the back drill surface;

s8, exposure: taking data through a DI machine, positioning and exposing, and exposing 10-13 grids of a ruler;

s9, developing: developing the unexposed position of the plate by sodium carbonate liquid with the concentration of 0.8-1.2%, wherein the developing speed is 3-3.5m/min, and blowing and drying by strong wind during developing;

s10, QC test: inspecting the appearance of the plate;

s11, photocuring: directly carrying out full-plate photocuring on the qualified plate, wherein an exposure ruler has 10-13 grids during photocuring;

s12, thermal curing: curing parameters were as 80 ℃ 60min +110 ℃ 30min +150 ℃ 60 min;

preferably, the ratio of the pore-filling ink curing agent to the main agent is 25%: 75 percent;

preferably, the viscosity of the surface oil is controlled at 100-140dpa.s, preferably at 120 dpa.s;

preferably, the printed circuit board is designed to be back-drilled, the back-drilled position needs to be subjected to solder mask hole plugging, the back-drilled surface of the printed circuit board downwards passes through a volcanic ash plate grinding machine, the plate grinding speed is 2.5-3m/min, preferably 2.8m/min, and the plate grinding drying temperature is 85-95 ℃, preferably 90 ℃;

preferably, the solder mask plug holes are plugged from the back face corresponding to the back drill, the ink just emerges from the back drill corresponding face after the plug holes are plugged, the printing face oil is finished on the board qualified in the plug holes within 15min, the printing face oil is printed on the back face corresponding to the back drill firstly, and then the back drill face is printed;

preferably, when the engineering data is manufactured, a back drill is drilled on the data at a position corresponding to the back drill surface;

the window opening point with the diameter of one side being 4-8mil smaller, preferably 6 mil;

preferably, the ruler is exposed 10-13, preferably 12, squares;

preferably, the back drilling surface of the printed circuit board is downward during development, the printed circuit board is developed through sodium carbonate liquid medicine with the concentration of 0.8-1.2%, preferably 1%, the developing speed is 3-3.5m/min, preferably 3.2m/min, and strong wind is shut off for drying during development;

preferably, the photocuring exposure ruler has 10-13 lattices, preferably 12 lattices.

Has the advantages that:

compared with the prior art, the invention has the beneficial effects that: the invention provides a method for improving solder mask bleeding of a back drilling hole of a printed circuit board, which comprises the steps of selecting plug hole ink to carry out plug hole operation from the back side corresponding to a back drill, controlling the retention time of the plug hole ink to a printing surface ink, printing the printing surface ink on the back side corresponding to the back drill, then printing a back drilling surface, digging a windowing point with the diameter smaller than the single side of the back drill on the data at the position corresponding to the back drilling surface when processing the data in engineering, developing the back drilling surface downwards through exposure, closing strong wind during development, drying by blowing, and carrying out photocuring.

Detailed Description

It will be understood that when an element is referred to as being "secured to" another element, it can be directly on the other element or intervening elements may also be present. When an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements may also be present. As used herein, the terms "fixed," "integrally formed," "left," "right," and the like are used for descriptive purposes only and elements of similar structure are identified by the same reference numerals.

Unless defined otherwise, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this invention belongs. The terminology used in the description of the invention herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the invention.

The method for improving the solder mask bleeding of the back drilling hole of the printed circuit board comprises the following steps:

s1, preparing hole plugging ink: mixing the curing agent and the main agent, and stirring for 15-30 min;

s2, preparing the face oil: mixing a curing agent and a main agent, adding 10-30ml of a diluent, stirring for 15-30min, measuring the viscosity of the uniformly stirred surface oil, and controlling the viscosity to be 140 dpa.s;

s3, plate preparation: passing the printed circuit board to be processed through a volcanic ash plate grinding machine, wherein the plate grinding speed is 2.5-3m/min, and the plate grinding drying temperature is 85-95 ℃;

s4, solder mask plug hole: carrying out hole plugging operation on the hole plugging ink from the back side corresponding to the back drill, and just enabling the ink to just emerge from the back drill corresponding side after hole plugging;

s5, printing face oil: printing surface oil on the plate with qualified plug hole within 15min, printing the back surface corresponding to the back drill on the printing surface oil, printing the back drill surface, and standing the inserting frame for 15-30min after printing;

s6, pre-baking: pre-baking at 72-75 deg.C for 40-45 min;

s7, data optimization: when the engineering data is manufactured, a windowing point which is 4-8mil smaller than the single side of the back drill diameter is dug on the data at the position corresponding to the back drill surface;

s8, exposure: taking data through a DI machine, positioning and exposing, and exposing 10-13 grids of a ruler;

s9, developing: developing the unexposed position of the plate by sodium carbonate liquid with the concentration of 0.8-1.2%, wherein the developing speed is 3-3.5m/min, and blowing and drying by strong wind during developing;

s10, QC test: inspecting the appearance of the plate;

s11, photocuring: directly carrying out full-plate photocuring on the qualified plate, wherein an exposure ruler has 10-13 grids during photocuring;

s12, thermal curing: curing parameters were as 80 ℃ 60min +110 ℃ 30min +150 ℃ 60 min;

in some embodiments of the present invention, the via-filling ink is a dedicated via-filling ink, and the ratio of the via-filling ink curing agent to the main agent is 25%: 75 percent;

in some embodiments of the invention, the viscosity of the finish is controlled at 120 dpa.s;

in some embodiments of the invention, the printed circuit board has a back drill design, the back drill position needs to be welded and plugged with a hole, the back drill surface of the printed circuit board passes through a volcanic ash plate grinding machine downwards, the plate grinding speed is 2.8m/min, and the plate grinding drying temperature is 90 ℃;

in some embodiments of the invention, the solder resist plug holes are plugged from the back side corresponding to the back drill, the printing surface oil is finished on the board with qualified plug holes within 15min, the printing surface oil is printed on the back side corresponding to the back drill firstly, and then the back drill side is printed;

in some embodiments of the invention, during the engineering data production, the data is located at the corresponding position of the back drilling surface;

digging a windowing point which is 6 mils smaller than the single side of the diameter of the back drill;

in some embodiments of the invention, the exposure ruler is 12 grids during exposure;

in some embodiments of the invention, the back drilling surface of the printed circuit board is downward during development, the concentration of the sodium carbonate liquid medicine is 1% for development, the development speed is 3.2m/min, and strong wind is turned off for drying during development;

in some embodiments of the invention, the photocuring exposure ruler has 12 grids;

the above description is only for the preferred embodiment of the present invention and not for the limitation of the concept and scope of the present invention, and various modifications and improvements made to the technical solution of the present invention by those skilled in the art without departing from the design concept of the present invention shall fall into the protection scope of the present invention, and the technical content of the present invention which is claimed is fully described in the claims.

The technical features mentioned above are combined with each other to form various embodiments which are not listed above, and all of them are regarded as the scope of the present invention described in the specification; also, modifications and variations may be suggested to those skilled in the art in light of the above teachings, and it is intended to cover all such modifications and variations as fall within the true spirit and scope of the invention as defined by the appended claims.