CN-121985481-A - Pressing method of vehicle-mounted thick copper FPC

Abstract

The invention provides a pressing method of a vehicle-mounted thick copper FPC, which realizes that a FCCL layer with a large thickness can be matched with an adhesive with a small thickness for use through the matching of a TPX adhesive-resisting film and vacuum false pressing, so that bubbles are discharged while the limit of the total thickness is met, the layering of a base material is avoided, the ratio of the thickness of the adhesive to the thickness of the FCCL layer of an adhesive contact bonding surface reaches 1:1.6, and the matching capability of the thicker FCCL layer and the thinner adhesive is effectively provided.

Inventors

• Yan Huihe

Assignees

• 安捷利（番禺）电子实业有限公司

Dates

Publication Date

20260505

Application Date

20260130

Claims (7)

1. 1. A pressing method of a vehicle-mounted thick copper FPC is characterized by comprising the following steps: S1, attaching an adhesive layer on one surface of a double-sided substrate; S2, setting a TPX (thermoplastic polyurethane) adhesive-resisting film on the surface of the adhesive layer and the other surface of the double-sided substrate, and performing vacuum false pressing; S3, removing the TPX adhesive-resisting film; and S4, attaching a single-sided substrate to the surface of the adhesive layer after vacuum false pressing, and pressing the single-sided substrate, the adhesive layer and the double-sided substrate to form the FPC.
2. 2. The method for bonding a thick copper FPC on a vehicle according to claim 1, wherein the single-sided substrate, the adhesive layer and the double-sided substrate are bonded by using a transfer press in S4.
3. 3. The method for laminating the vehicle-mounted thick copper FPC according to claim 2, wherein the pressure of the pressure transmitter is controlled in a sectional manner, the pressure of the pressure transmitter is increased and then kept for a period of time, and then gradually decreased, and the temperature of the pressure transmitter is increased and then kept for a period of time, and then gradually decreased.
4. 4. The method of claim 3, wherein the sectional control comprises a first lamination stage, a second lamination stage, a third lamination stage and a fourth lamination stage; The temperature is gradually increased to the temperature set value required by the second pressing stage in the first pressing stage, then the constant temperature is maintained, the temperature is gradually reduced to the temperature set value required by the third pressing stage in the second pressing stage, then the constant temperature is maintained, the temperature is gradually reduced to the temperature set value required by the fourth pressing stage in the third pressing stage, then the constant temperature is maintained, and the pressing is completed.
5. 5. The method for pressing the vehicle-mounted thick copper FPC according to claim 4, wherein the pressure is gradually increased to a pressure set value required by a second pressing stage in the first pressing stage, then the current pressure value is maintained in the second pressing stage to a fourth pressing stage, the pressure is gradually decreased to a pressure set value required by a fifth pressing stage in the fourth pressing stage, and the pressing is completed.
6. 6. The pressing method of the vehicle-mounted thick copper FPC according to claim 1, wherein the thickness of the TPX (thermoplastic polyurethane) adhesive-resistant film is more than or equal to 120 mu m.
7. 7. The pressing method of the vehicle-mounted thick copper FPC according to claim 1, wherein in S2, vacuum false pressing is carried out by utilizing a vacuum press, the temperature range of the vacuum press is 110+/-5 ℃, the pre-pressing time is 10-15S, the molding time is 10-15S, and the pressure is 15+/-2 Kgf/cm 2 .

Description

Pressing method of vehicle-mounted thick copper FPC Technical Field The invention relates to the technical field of FPC (flexible printed circuit), in particular to a pressing method of a vehicle-mounted thick copper FPC. Background The thick copper FPC is a flexible printed circuit board (Flexible Printed Circuit) with the copper foil thickness of 35-40 mu m, and has the core characteristics of high current carrying capacity, excellent heat dissipation, improved mechanical strength and high temperature resistance compared with the common FPC (copper is usually 12-35 mu m). The ratio of the thickness of the FCCL layer of the thick copper FPC to the thickness of the adhesive is generally 1:1, and the FCCL layer with larger thickness is limited by the total thickness of the FPC, for example, the FCCL layer with the thickness of 35-40 μm can only be matched with the adhesive with the thickness of 25 μm, so that the adhesive-copper ratio is obviously lower than 1:1 (the adhesive-copper ratio refers to the ratio of the thickness of the adhesive to the thickness of the copper layer), and bubbles can be generated between the FCCL layer and the adhesive due to insufficient filling of the adhesive in the laminating process, and further, the base material layering can be caused. For example, in chinese application No. 202411908338.7, patent document with publication date 2025.11.18 discloses a method for manufacturing a wireless FPC, which discloses vacuum dummy pressing a protective film to overcome the defect of air bubbles. However, the method comprises the steps of firstly carrying out vacuum false pressing on the protective film, then carrying out lamination on the protective film after the vacuum false pressing is finished with the FPC, and not carrying out vacuum false pressing on the protective film and the FPC in a lamination state, so that bubbles between lamination substrates and bubbles between lines are difficult to remove. Disclosure of Invention In view of the above, the invention aims to provide a pressing method of a vehicle-mounted thick copper FPC, which solves the problems of air bubbles and layering by matching a TPX (thermoplastic polyurethane) adhesive-resistant film with vacuum false pressing, realizes that a FCCL (flexible printed circuit) layer with a large thickness can be matched with an adhesive with a small thickness for use, and effectively improves the adhesive-copper ratio of the adhesive. In order to solve the technical problems, the technical scheme adopted by the invention is that the pressing method of the vehicle-mounted thick copper FPC comprises the following steps: s1, attaching an adhesive layer on one surface of a double-sided substrate. S2, setting a TPX (thermoplastic polyurethane) adhesive-resisting film on the surface of the adhesive layer and the other surface of the double-sided base material, and performing vacuum false pressing. S3, removing the TPX adhesive-resisting film. And S4, attaching a single-sided substrate on the surface of the adhesive layer after vacuum false pressing, and pressing to form the FPC. Preferably, in S4, the single-sided substrate, the adhesive layer and the double-sided substrate are laminated by using a transfer press. Preferably, the pressure of the pressure transmission machine is controlled in a sectional mode, the pressure of the pressure transmission machine is increased and then kept for a period of time, and then gradually reduced, and the temperature of the pressure transmission machine is increased and then kept for a period of time, and finally gradually reduced. Preferably, the sectional control includes a first lamination stage, a second lamination stage, a third lamination stage and a fourth lamination stage. The temperature is gradually increased to the temperature set value required by the second pressing stage in the first pressing stage, then the constant temperature is maintained, the temperature is gradually reduced to the temperature set value required by the third pressing stage in the second pressing stage, then the constant temperature is maintained, the temperature is gradually reduced to the temperature set value required by the fourth pressing stage in the third pressing stage, then the constant temperature is maintained, and the pressing is completed. Preferably, the pressure is gradually increased to the pressure set value required by the second pressing stage in the first pressing stage, then the current pressure value is kept in the second pressing stage to the fourth pressing stage, the pressure is gradually reduced to the pressure set value required by the fifth pressing stage in the fourth pressing stage, and the pressing is completed. Preferably, the thickness of the TPX adhesive-resistant film is more than or equal to 120 mu m. Preferably, in S2, vacuum false pressing is carried out by using a vacuum press, wherein the temperature range of the vacuum press is 110+/-5 ℃, the pre-pressing time is 10-15S, the