KR20020085183A - Attatchment method of flexible printed circuit board using adhesive - Google Patents

Abstract

PURPOSE: An attatchment method of a flexible printed circuit board using an adhesive is provided to reduce effectively generation of wrinkles and cracks on the flexible PCB by using the adhesive. CONSTITUTION: A circuit formation process(10) is to form a circuit in a raw material. The circuit formation process(10) includes a raw material cutting process(11), a dry film adhesion process(12), an exposing and developing process(13), a corrosion and detachment process(14), and a dry process(15). A selection process for connecting a through-hole can be selectively performed between the raw material cutting process(11) and the dry film adhesion process(12). A protection process(20) is performed after the circuit formation process(10) is finished. The protection process(20) includes a plating process(21) and a cutting process(22). A post process(30) is performed after the protection process(20) is finished. The post process(30) includes a printing process(31), an infrared heating process(32), a painting process(33), an adhering process(34), and a hot press process(35). An applicable technique process(40) is to apply a wire bonding method and a surface mounting method on a soft PCB. The applicable technique process(40) includes a surface mounting and wire bonding process(41) and a detachment process(42).

Description

Bonding method of flexible printed circuit board using adhesive paint {Attatchment method of flexible printed circuit board using adhesive}

The present invention is wire bonding of surface mounts and chips of components using an adhesive coating that is optimally blended with a curing agent of various polymer components such as epoxy, phenol, and imidazole, and infrared exposure or heat drying ink. And a method for bonding a flexible printed circuit board using adhesive paints having a soft and strong adhesiveness for use in tab bonding and bonding of a flexible printed circuit board and a reinforcement plate for package purposes.

Generally, conventional adhesives include solvent-based adhesives, latex adhesives, pressure-sensitive adhesives, hot-melt adhesives, and reactive adhesives. Adhesives using various polymers such as adhesives or combinations thereof are used. Especially in the case of flexible printed circuit boards, double pressure-sensitive, thermoset and thermoplastic adhesives are mainly used. Common characteristics of all are due to strong adhesion and resin flow, chemical resistance

(Chemical resistance), thermal resistance, etc. were the main factors.

However, in the above-described adhesives, in the process, after heating the reinforcing plate, the adhesive is applied to the reinforcing plate, and then bonded to the flexible printed circuit board, and then wire bonding of the surface mounts and chips of the parts. And since the adhesiveness is very strong when the tab bonding, and then peeled off after the package is completed, there is a problem that the flexible printed circuit board is wrinkled, cracking, residue or the like.

Accordingly, the present invention has been made in order to solve the above problems, a reinforcing plate of a pressure-sensitive adhesive compounded with a curing agent such as imidazole-based, acrylic, phenol-based, epoxy-based in an appropriate ratio for the infrared exposure or thermal drying ink The purpose of the present invention is to provide a method for bonding a flexible printed circuit board using an adhesive paint to effectively reduce the occurrence of wrinkles, cracks, residues, etc. of the flexible printed circuit board by applying it to the bonding process of the flexible printed circuit board.

Bonding method of a flexible printed circuit board using the adhesive paint according to the present invention for achieving the above object, by applying a protective shield material and a surface treatment agent to the substrate subjected to the circuit forming process of forming a circuit on the raw material, After the protective treatment process to plate the parts and cut the appearance, and then to the flexible printed circuit board and the reinforcement plate after the close processing by heat, pressure and time factors, the surface mounting of the components, wire bonding and tap bonding of chips And, In the method of manufacturing a flexible printed circuit board comprising a packaged application technology process, the post-treatment step is a reinforcing plate printing step of printing a reinforcing plate to be bonded to the flexible printed circuit board and the printing step At least one or more of the paint input step of applying a pressure-sensitive adhesive paint with a curing agent added to the reinforcing plate, infrared radiation or heat drying However, an infrared heating step for curing the adhesive paint by heating the reinforcement plate, a temporary adhesive step of bonding the reinforcement plate and the flexible printed circuit board by the injected adhesive paint, and the bonded reinforcement plate and the flexible printed circuit. After the hot press step for crimping the substrate, the surface mounting / chip bonding of the component for placing the component on the flexible printed circuit board after the hot press step, and the wire bonding step for the surface mounting / chip of the component Characterized in that the peeling step of separating the flexible printed circuit board and the reinforcement plate.

1 is a process chart showing the process of the bonding method of the flexible printed circuit board using the adhesive paint according to the present invention.

Explanation of symbols on the main parts of the drawing

10: circuit forming process 20: protective treatment process

30: post-processing step 31: reinforcement plate printing step

32: infrared heating step 33: adhesive coating step

34: temporary adhesion step 35: hot press step

40: Applied Technology Process 41: Surface Mount / Wire Bonding Step

42: adhesive paint peeling step 43: inspection and shipping step

Hereinafter, with reference to the accompanying drawings, the present invention will be described in detail.

As shown in FIG. 1, the process of manufacturing a flexible printed circuit board includes a circuit forming step 10 of forming a circuit on a raw material, and applying a protective shield material and a surface treatment agent to the circuit board having undergone the circuit forming process. The surface treatment of chips and chips is carried out through a protective treatment process (20) of plating the site and cutting the appearance, and a post-treatment process (30) of bringing the flexible printed circuit board and the reinforcement plate into close contact with heat, pressure and time factors. It consists largely of wire bonding and tap bonding, and an application process 40 for package purposes.

Here, the circuit forming process (10) is a raw material input / cutting step (11) for cutting the desired size or area by inputting a raw material using a material such as polyimide again, and the circuit is designed by the artwork process (artwork) process Dry film adhesion step (12) for adhering the film to the raw material, exposure / development step (13) to peel off the dry film of the remaining part leaving the hardened part by the light by infrared or heat exposure, and the dry film is peeled off Corrosion / peeling step (14) and the drying (15) step of removing the dry film after the corrosion of the unnecessary copper foil with chemicals.

At this time, between the raw material input / cutting step (11) and the dry film bonding step (12) is a through-hole formed by the drilling by any one method of electroless copper plating or electrolytic copper plating by drilling during the manufacture of double-sided or multilayer printed circuit board The selection process 100 for electrically connecting the may be further included.

In addition, the protective treatment process 20 is plated so that the copper foil is exposed to the connector or part when the flexible printed circuit board is assembled into a set of the cover shield-bonded protective cover material. And cutting out the appearance.

In addition, the post-processing step 30 is a reinforcing plate printing step 31 for printing a reinforcing plate to be bonded to the flexible printed circuit board, and infrared heating for heating the reinforcing plate by at least one means of infrared or thermal radiation. Step 32, a paint input step 33 for applying a pressure-sensitive adhesive paint with a curing agent added to the reinforcing plate through the infrared heating step 32, and the reinforcement plate and the flexible printed circuit board by the injected adhesive paint And a hot pressing step 35 for pressing the temporary bonding step 34 to bond the reinforcing plate and the flexible printed circuit board bonded to the temporary bonding step 34.

Here, the reinforcement plate printing step 31 is a previous step for applying a soft adhesive paint on the rigid reinforcement plate using a material such as epoxy, phenol, or acrylic, and the like due to the ductility and fineness of the pattern of the flexible printed circuit board itself. Due to the surface mounting of the components, the wire bonding and tap bonding of the chips, and the step of printing the reinforcement plate to combine with the flexible printed circuit board in order to eliminate the difficulty of mounting the component in the correct position.

Here, the adhesive paint is blended at least one of the imidazole-based, phenol-based, acryl-based materials in the basic ratio of 6% with respect to the ink for infrared exposure or heat drying, and also the ratio of the curing agent to facilitate adhesion and peeling It is desirable to be able to adjust the 2 to 100%.

On the other hand, the post-treatment process 30 is a pre-stage preparation process for the application technology process 40 is a wide selection process. After coating or sputtering on the reinforcing plate, apply soft desorption and adhesive material, and then temporarily harden it by infrared or heat method. Then, after the protective treatment process (20) has been temporarily bonded, the product is temporarily bonded. Keep it tight.

In addition, the application technology process 40 shows the application of the wire bonding and surface mounting technology to a flexible printed circuit board among the processes and products in the case where soft detachment | bonding and adhesion are needed as an Example.

The ductility itself and the fineness of the pattern sometimes make it difficult to mount the parts at the correct position when performing surface mount technology or wire bonding (41), and various kinds of jigs (JIG) such as SUS / AL / phenol / epoxy However, since they do not have adhesive strength by themselves, they have no choice but to use adhesives separately or use down and up layers.

In addition, in the case of using the existing adhesives, the adhesive strength is good, but it is difficult to peel off, leaving stress and residue on the flexible substrate.In the case of using the up / down layer, the up layer is used after applying the cream solder in the surface mounting technology. It is preferable to use the pressure-sensitive adhesives as described above because the product must be fixed separately.

As described above, the application process of the adhesive coating according to the present invention can solve the disadvantage that the flexible printed circuit board itself can not be a surface mount, wire bonding and tap bonding of chips, and package configuration, as an adhesive It is effective in minimizing the influence on the flexible printed circuit board of existing adhesives such as wrinkles, cracks, and residues while having a sufficient role.

Claims (1)

After applying the protective shielding material and surface treatment agent to the substrate that has undergone the circuit forming process (10) of forming the circuit in the raw material, and after the protective treatment process (20) to cut the appearance by plating the exposed part and the flexible printed circuit board and Flexible printed circuit consisting of surface mounting of parts, wire bonding and tap bonding of chips, and application technology process 40 for packaging through a post-treatment step 30 that closely adheres the reinforcement plate to heat, pressure and time factors. In the manufacturing method of the substrate, The post-processing step 30 includes a reinforcing plate printing step 31 of printing a reinforcing plate to be bonded to the flexible printed circuit board; A paint input step 33 of applying an adhesive paint to which the curing agent is added to the reinforcing plate subjected to the printing step; An infrared heating step (32) for curing the adhesive paint by heating the reinforcing plate by at least one means of infrared radiation or heat drying; A temporary adhesion step 34 of adhering the reinforcement plate and the flexible printed circuit board by the injected adhesive paint; A hot press step 35 for pressing the bonded reinforcement plate and the flexible printed circuit board; A wire bonding step (41) of surface mounting / chips of a component for placing the component on the flexible printed circuit board subjected to the hot press step; And a peeling step (42) of separating the flexible printed circuit board and the reinforcing plate after the wire mounting step of the surface mounting / chips of the component.