Soft or hard double-sided circuit board manufacturing method
Technical field
This invention relates to a kind of preparation method of double-sided PCB, and particularly a kind of soft or hard double-sided circuit board manufacturing method, belongs to circuit board print field.
Background technology
The product substrate composite structure of traditional double face rigid-flexible circuit board is that one side hardboard adds one deck one side soft board and combines by sticker.
Main production: 1, one side PCB substrate is first slotted in specific region; (object of fluting is in order to be convenient to herein PCB be taken off lid in the final stage of product in advance); 2, AD glue is first removed part glue with cutting mode in specific region; 3, PI stiffening plate is sticked in the specific region on one side FPC substrate; 4, with AD glue as sticker in intermediate layer, one side FPC substrate and one side PCB substrate are combined into one with pressing mode, now PI stiffening plate be also contained in the inside. Substrate after pressing has formed the structure of two-sided soft or hard combination.
Existing product structure &processes shortcoming: 1, electroplate or have liquid medicine to penetrate into substrate internal layer from PCB fluting while crossing the horizontal line of wet process, cause liquid medicine to pollute substrate internal layer, in the production process of postorder, also have liquid medicine and flow backwards out from internal layer, thereby cause substrate to occur that quality problems cause product rejection simultaneously; 2, because PCB slots in advance, in the time of pressing and forming, FPC substrate has been slotted without supporting because of the back side, will cause FPC substrate to have depressed phenomenon, occurs obvious difference of height, and circuit is made and welding resistance when making will cause many quality problem because of the problem of difference of height; 3, because part above FPC needs reinforcing, with existing product structure pressing, internal layer, because FPC substrate after having reinforcement will cause pressing has obvious protruding phenomenon, because of the out-of-flatness of FPC substrate surface, has protruding phenomenon will cause many quality problem while causing circuit making and welding resistance to make.
Summary of the invention
Goal of the invention: the object of this invention is to provide a kind of substrate PCB fluting place back substrate generation depression, inner part of FPC in synthetic pressing process can avoided has the local substrate of reinforcement to produce protruding soft or hard double-sided circuit board manufacturing method.
Technical scheme: a kind of soft or hard double-sided circuit board manufacturing method, comprises the following steps:
A) select a PCB one side substrate to add one according to the thickness of product and replace an original one side substrate without copper FR4, for example: the thickness of former one side substrate is 1.0MM, present add a 0.2MM with a 0.8MM one side substrate and synthesize replacement without the FR4 of copper, concrete material is selected to carry out free collocation according to the thickness of product;
B) carry out in advance water-proofing treatment in PCB one side substrate slot area;
C) in synthetic material, go out in advance a gap without the specific slot area of copper FR4, be beneficial to substrate after synthetic and in the time forming the final stage of product, take off lid and use;
D) have the specific region of reinforcement at FPC, first to carrying out hollow out processing without the equitant position of copper FR4, exempting from substrate FPC real estate after pressing is synthetic has protruding phenomenon;
What e) use that hollow out processed is used as jig plate without copper FR4 and uses, and AD glue, with hole contraposition, is distributed in to plate face, through colding pressing, makes AD glue and combines in advance without copper FR4;
F) and then by stiffening plate by clogging laminating without the position of copper FR4 hollow out processing, post rear false fixing with flatiron, then through too fast press hot pressing compacting.
For the ease of product in the end the stage take off lid, the gap of going out in described step c overlaps with PCB slot area.
Describedly need to arrange in pairs or groups according to the thickness of PI stiffening plate without copper FR4 material thickness, within the be controlled at ± 0.05MM of thickness difference of the thickness of described FR4 material and PI stiffening plate, otherwise the phenomenon of substrate surface projection cannot solve.
Beneficial effect: 1, can effectively solve substrate PCB fluting place back substrate in synthetic pressing process and produce the bad phenomenon caving in, improve the quality that product circuit and welding resistance are made; 2, can effectively solve substrate inner part of FPC in synthetic pressing process has the local substrate of reinforcement to produce protruding bad phenomenon, has improved the quality that product circuit and welding resistance are made; 3, use two-layer FR4 composite structure, can substrate produce the bad phenomenon of depression, while avoiding electroplating in process of production or crossing the horizontal line of wet process, have liquid medicine to penetrate into substrate internal layer from PCB fluting.
Brief description of the drawings
Fig. 1 is product structure schematic diagram of the present invention;
Fig. 2 is the synthetic pressing structure schematic diagram of substrate of the present invention;
Fig. 3 is the parameter list of the synthetic pressing of the present invention.
Detailed description of the invention
Below in conjunction with accompanying drawing, the invention will be further described.
As shown in Figure 1, a kind of soft or hard double-sided circuit board manufacturing method, comprises the following steps:
A) select a PCB one side substrate to add one according to the thickness of product and replace an original one side substrate without copper FR4, for example: the thickness of former one side substrate is 1.0MM, present add a 0.2MM with a 0.8MM one side substrate and synthesize replacement without the FR4 of copper, concrete material is selected to carry out free collocation according to the thickness of product; Describedly need to arrange in pairs or groups according to the thickness of PI stiffening plate without copper FR4 material thickness, within the be controlled at ± 0.05MM of thickness difference of the thickness of described FR4 material and PI stiffening plate, otherwise the phenomenon of substrate surface projection cannot solve.
B) carry out in advance water-proofing treatment in PCB one side substrate slot area;
C) in synthetic material, go out in advance a gap without the specific slot area of copper FR4, gap overlaps with PCB slot area, is beneficial to substrate after synthetic and in the time forming the final stage of product, takes off lid and use;
D) there is the specific region of reinforcement at FPC, first to carrying out hollow out processing without the equitant position of copper FR4, size is monolateral than the large 0.2MM of stiffening plate, to the reinforcement processing of stepping down, avoid synthesizing pressing process MR medium reinforcing by substrate jack-up at substrate, avoid substrate FPC real estate after pressing is synthetic to have protruding phenomenon;
What e) use that hollow out processed is used as jig plate without copper FR4 and uses, and AD glue, with hole contraposition, is distributed in to plate face, through colding pressing, makes AD glue and combines in advance without copper FR4;
F) and then by stiffening plate by clogging laminating without the position of copper FR4 hollow out processing, post rear false fixing with flatiron, then through too fast press hot pressing compacting.
The present invention, in the case of the structure and original design that do not affect final finished, by change product substrate composite structure in process of production and local design, has reached the feasibility that can produce in batches, has improved the quality of product.
Must select the material of high TG value without the material of copper FR4, the synthetic pressing maximum temperature of substrate can not exceed the TG value without copper FR4. See Fig. 3.
Pressing maximum temperature is set and can not be exceeded TG value without copper FR4 (for example: TG Zhi Wei≤170 DEG C of FR4, the setting of pressing maximum temperature can not exceed 170 DEG C).
As shown in Figure 2, pressing auxiliary material are selected KY3001 mould release membrance, KY3002 filling film.