CN102223762B - High-precision jacquard glass fiber fabric - Google Patents

Abstract

The invention provides a method for manufacturing a high-precision printed circuit board. The known jacquard weaves a high-precision jacquard glass fiber cloth base material, pre-cuts the base material, impregnates the adhesive and dries it, and performs precise cutting according to the actual circuit after cooling. And it is subjected to surface treatment, electroplating and etching to obtain the high-precision printed circuit board of the present invention. The high-precision printed circuit board of the invention can meet the requirements of miniaturization, high precision, large batch and high efficiency production, and has very broad market prospects.

Description

High precision jacquard glass fiber cloth

technical field

The present invention relates to a method for manufacturing a printed circuit board, and more particularly relates to a method for manufacturing a printed circuit board with jacquard glass fiber cloth as a base material, which can be applied to high-density, high-precision electronic component installation.

Background technique

In recent years, with the continuous development of electronic products towards miniaturization, thinning, light weight, and high performance, the printed circuit boards need to be installed with more electronic components in a smaller area while the size is getting smaller. , and in the current large-scale production methods, for the sake of production efficiency, the method of automatically inserting electronic components on the assembly line is generally used. For such automatic insertion technology, it is required that the electronic components inserted each time can be accurately positioned on the printed circuit board.

Printed circuit boards in the prior art usually use glass fiber cloth made of glass fiber as the base material. In the prior art, a large number of plain glass fiber cloth woven by air-jet looms are used. Because the warp and weft yarns will form on the surface Protruding tissue points, so its surface flatness is poor and usually cannot meet the production requirements of high-precision and high-density circuit boards. At the same time, due to the expansion and/or Shrinkage, and the interweaving structure of the warp and weft yarns in plain weave fabrics can manifest this slight expansion and/or shrinkage as warping of the diagonal edges of the substrate, which is especially unsuitable for high-precision, high-density circuit boards.

Also use the glass fiber mat made by non-woven process in the prior art, but for this non-woven glass fiber mat, although its surface flatness can be ensured to a certain extent by lamination process, but due to process requirements, this The thickness of the fiber mat is usually thick, which obviously does not meet the requirements of miniaturization, high precision, and high density circuit boards. At the same time, the fiber mat will also warp to a certain extent after subsequent processing, which also cannot meet the requirements of high precision, high precision, and high density circuit boards. Demand for high-density plug-in electronic components.

Therefore, with the continuous development of miniaturization of circuits and densification of circuit board components, the demand for high-precision insertion of electronic components on printed circuit boards has become more urgent.

Contents of the invention

Aiming at the defects of the printed circuit board in the prior art, the technical problem to be solved by the present invention is the problem that the surface of the glass fiber cloth base material in the prior art is uneven and easy to warp, and a kind of electronic component insertion surface is flat and not easy to be warped. Warped printed circuit board fabrication method.

In order to solve this technical problem, the present invention realizes through following technical scheme:

A method for manufacturing a high-precision printed circuit board, comprising the following steps: weaving a high-precision jacquard glass fiber cloth base material by a jacquard process: selecting a single glass fiber or a low-twist glass fiber with a twist of 1.4 to 2.0 turns/50 mm as the warp yarn Jacquard weaving with weft yarns, wherein the warp yarns and weft yarns form a roughly circuit-shaped jacquard pattern; pre-cutting: cutting according to a preset jacquard pattern; impregnating adhesive: impregnating the cut glass fiber cloth substrate with adhesive , the adhesive includes the following raw materials in parts by weight: 45 to 55 parts of phenolic resin, 35 to 45 parts of epoxy resin, 20 to 40 parts of solvent, and 5 to 35 parts of auxiliary agent, and the solvent is selected from two One or more of methyl formamide, ethylene glycol monomethyl ether, butanone, acetone, cyclohexanone, propylene glycol monomethyl ether, propylene glycol monomethyl ether acetate and toluene, and the additives include epoxy diluent , silicon dioxide, flame retardant, curing initiator and cross-linking aid; in addition, particulate fillers are added to the adhesive, and the particulate fillers include inorganic fillers and/or organic fillers, and the inorganic fillers are selected from SiC, SiO ₂ , TiO _2. One or more of Al ₂ O ₃ , MgO and AlN, and the organic filler is selected from one of benzodiaminotriazine, polyamide, polyimide, melamine resin, and epoxy resin or more; drying: drying at 180-250°C for 0.5-1.5 hours; after cooling, it can be precisely cut according to the size of the actual circuit board, and after surface treatment, electroplating and etching, the circuit board described in the present invention can be obtained. high-precision printed circuit boards.

By forming a jacquard pattern in the area corresponding to the circuit on the surface of the glass fiber cloth, and weaving the warp and weft yarns into a rough circuit shape, it is possible to ensure that the relative position of the entire circuit is maintained even if the glass fiber slightly expands and/or shrinks. basically stable, so as to ensure that the relative positions between the insertion positions will not change unpredictablely; the combination of adhesive and filler as described in the present invention can ensure that the dielectric constant of the printed circuit board is low, The dielectric loss is small.

According to the manufacturing method of the high-precision printed circuit board as described in the present invention, it is possible to obtain a printed circuit board with high surface flatness, high working temperature tolerance, high frequency, low dielectric constant and small dielectric loss , well meet the needs of the industry.

Description of drawings

Fig. 1 is a partial schematic view of the first embodiment of the high-precision glass fiber cloth of the present invention;

Fig. 2 is a partial schematic diagram of the second embodiment of the high-precision glass fiber cloth of the present invention;

specific implementation plan

Describe the concrete technical scheme of the present invention in detail below by several preferred embodiments

Example 1

Jacquard weaving: select glass fiber with a diameter of 0.009-0.05mm, and weave the circuit area shown in Figure 1 through the jacquard weaving process. Since the width of the jacquard machine is usually about 190-350 cm, the width of the entire glass fiber cloth Multiple identical circuit areas as shown in Figure 1 can be formed as required to meet the needs of modern mass production. The central circuit area in Figure 1 is the preset area that needs to form a circuit. In this embodiment, the front side of the fabric Only warp 1 can be seen, that is, only warp 1 or weft 2 is on the side carrying electronic components when the printed circuit board is finally formed. The rest of the area other than the central area is the surrounding transition area, where the warp 1 and weft 2 are normally interwoven to form a plain weave, thereby forming a firm weave structure.

Pre-cutting: Cut according to the jacquard shape forming the central circuit area, and retain some of the surrounding transition areas to ensure that the cut glass fiber cloth substrate can maintain the basic shape.

Adhesive impregnation: The high-precision glass fiber cloth base material obtained by cutting is impregnated in the adhesive. The adhesive includes the following raw materials in parts by weight: 45-55 parts of phenolic resin, 35-45 parts of epoxy Resin, 20-40 parts of solvent, and 5-35 parts of auxiliary agent, the solvent is selected from dimethylformamide, ethylene glycol monomethyl ether, butanone, acetone, cyclohexanone, propylene glycol monomethyl ether, One or more of propylene glycol methyl ether acetate and toluene, and the auxiliary agent includes epoxy diluent, silicon dioxide, flame retardant, curing initiator and crosslinking auxiliary agent. Adding particulate fillers to the binder, the particulate fillers include inorganic fillers and/or organic fillers, and the inorganic fillers are selected from one or more of SiC, SiO ₂ , TiO ₂ , Al ₂ O ₃ , MgO and AlN, The organic filler is selected from one or more of benzodiaminotriazine, polyamide, polyimide, melamine resin and epoxy resin.

As a preferred embodiment of the present invention, the solvent in the adhesive used for the printed circuit board is preferably dimethylformamide and methyl ethyl ketone, and may also include one or more mixed solvents in any proportion.

Drying: Take out the glass fiber cloth substrate impregnated with the adhesive, and dry it at a temperature of 180-250°C for 1 hour.

After cooling, it is precisely cut according to the size of the actual circuit board, and after surface treatment, electroplating and etching, the high-precision printed circuit board of the present invention can be obtained.

In addition, depending on the application of the printed circuit board, multiple high-precision glass fiber cloths impregnated with adhesives can be layered and then impregnated to obtain a multi-layer high-precision printed circuit board substrate that meets the needs of thickness and hardness.

Example 2

Compared with Example 1, the difference is that the central circuit area has several interweaving areas of warp yarn 1 and weft yarn 2 when the jacquard machine is weaving. The structure of the circuit area in the material is stable, and it can also be used for drilling holes in the final circuit board.

Other steps are with embodiment 1.

In addition, this embodiment 2 only shows the case where the central region has several dot-shaped interleaving regions. In fact, continuous interweaving regions can be designed according to the needs of circuit wiring, so that the shape of the non-interleaving region is consistent with the final circuit shape to be formed. Correspondingly, by designing the high-precision glass fiber cloth base material in this way, even if the glass fiber shrinks or stretches during processing, the amount of shrinkage or stretching in the entire circuit area is basically the same, and its deformation direction is also completely Similarly, even if the entire circuit board is warped to a certain extent, the relative positional relationship of the entire circuit will not change unpredictablely, which is also very beneficial for the design and insertion of high-precision circuits.

Example 3

Compared with Examples 1 and 2, the difference is that the surface of the Jacquard woven base fabric has multiple different circuit areas, that is, different circuit shapes can be designed on the continuously woven glass fiber cloth according to the different quantities required by customers.

Other steps are with embodiment 1 and 2.

By arranging different circuit areas in the width direction, some requirements for permitting small batches can be met, and at the same time, the overall weaving cost can be reduced.

Claims (1)

1. the manufacture method of a high accuracy printed circuit board (PCB) comprises the steps:

Jacquard process is weaved high accuracy jacquard weave glass fabric base material: choose the low twist glass fiber of individual glass fibers or the twist 1.4～2.0 between changeing/50 millimeters and carry out jacquard weaving as warp thread and weft yarn, wherein said warp thread and weft yarn form the roughly figured pattern of circuitry shapes;

Pre-cut: the figured pattern according to preset carries out cutting;

Dip bonding agent: with the glass fabric base material dip bonding agent after the cutting; Adhesive comprises the raw material of following weight portion: 45～55 parts phenolic resins; 35～45 parts epoxy resin; 20～40 parts solvent; And 5～35 parts auxiliary agent, said solvent is selected from one or more in dimethyl formamide, glycol monoethyl ether, butanone, acetone, cyclohexanone, propylene glycol monomethyl ether, 1-Methoxy-2-propyl acetate and the toluene, and said auxiliary agent comprises epoxide diluent, silicon dioxide, fire retardant, curing initiator and crosslinking coagent; Add particulate filler in the adhesive in addition, said particulate filler comprises inorganic filler and/or organic filler, and inorganic filler is selected from SiC, SiO ₂, TiO ₂, Al ₂O ₃, among MgO and the AlN one or more, organic filler is selected from one or more in benzo diaminourea triazine, polyamide, polyimides, melamine resin, the epoxy resin;

Oven dry: dried 0.5～1.5 hour for 180～250 ℃;

Carry out accurate cutting based on side circuit plate size more after cooling, and after it is carried out surface treatment, plating and etching, promptly obtain the high accuracy printed circuit board (PCB).

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