CN-121991507-A - Flexible metal sheathing panel and method of making same

Abstract

The invention relates to the application of TPI with different components to the bonding surface and non-bonding surface areas of metal foil respectively, so as to minimize the bonding force between the non-bonding surface areas TPI and polyimide protective film during the lamination process, thereby avoiding the curling phenomenon of the single-sided flexible copper-clad plate during the lamination process manufacture.

Inventors

• Yin Xianyou
• Pu Shijuan
• WU SHIXUN
• HAN YANDONG
• JIN HUA

Assignees

• 宜兴创聚电子材料有限公司

Dates

Publication Date

20260508

Application Date

20260204

Claims (20)

1. 1. A composition for forming a thermoplastic polyimide comprising a polyamic acid, characterized in that the polyamic acid comprises structural units derived from a dianhydride selected from one or more of PMDA, BPDA, BTDA, ODPA and TMEG and a diamine selected from one or more of p-PDA, m-PDA, ODA, BAPP, TPE-R, TPE-Q, m-Tolidine, o-Tolidine and DABA.
2. 2. The composition of claim 1 wherein said dianhydride comprises PMDA and/or said diamine comprises one or more of TPE-R, ODA and BAPP, said PMDA comprising 70 mole% or more, or 80% or more of said dianhydride and/or one or more of TPE-R, ODA and BAPP comprising 70 mole% or more, or 80% or more, or 90% or more of said diamine.
3. 3. The composition according to claim 1, further comprising an aprotic polar solvent selected from DMAc, DMF, DMSO, DEAc, DEF, DMPA and NMP.
4. 4. A composition according to claim 3 wherein the diamine and dianhydride comprise 5 to 30wt% of the composition on a solids basis.
5. 5. The composition according to claim 1, further comprising a filler comprising one or more of silica, calcium phosphate, alumina, boron nitride and aluminum nitride, the filler being dispersed in the aprotic polar solvent at a content of 0.1 to 0.6wt% based on the solid content in the composition.
6. 6. Thermoplastic polyimide comprising structural units obtained by polymerization of a dianhydride selected from one or more of PMDA, BPDA, BTDA, ODPA and TMEG and a diamine selected from one or more of p-PDA, m-PDA, ODA, BAPP, TPE-R, TPE-Q, m-Tolidine, o-Tolidine and DABA.
7. 7. The thermoplastic polyimide according to claim 6, wherein the dianhydride comprises PMDA and/or the diamine comprises one or more of TPE-R, ODA and BAPP, the PMDA comprises 70mol% or more, or 80 mol% or more, of the dianhydride and/or the one or more of TPE-R, ODA and BAPP comprises 70mol% or more, or 80 mol% or more, or 90 mol% or more, of the diamine.
8. 8. The thermoplastic polyimide according to claim 7, further comprising a filler comprising one or more of silica, calcium phosphate, alumina, boron nitride and aluminum nitride, the filler comprising 0.1 to 0.6wt% based on the weight of the thermoplastic polyimide.
9. 9. The thermoplastic polyimide according to claim 6, which is a crystalline polymer or a near crystalline polymer.
10. 10. Thermoplastic polyimide obtained from the composition of any of claims 1 to 5.
11. 11. A layered structure comprising: The insulation substrate layer is a polyimide layer, the insulation bonding layer is a thermoplastic polyimide layer, and the insulation isolation layer is a thermoplastic polyimide layer.
12. 12. The layered structure according to claim 11, said insulating barrier layer being obtained from the composition according to any one of claims 1 to 5 or the thermoplastic polyimide according to any one of claims 6 to 10.
13. 13. The layered structure according to claim 11, wherein the thickness of the insulating base material layer is 8 to 100 μm, and the thickness of the insulating adhesive layer and the insulating spacer layer is 1 to 15 μm, respectively.
14. 14. The layered structure according to claim 11, wherein the insulating substrate layer is between the insulating adhesive layer and the insulating barrier layer.
15. 15. The layered structure according to claim 11, further comprising a conductive layer, the conductive layer being bonded to the insulating adhesive layer, and the conductive layer being at least one of copper foil, aluminum foil, gold foil, silver foil, or nickel foil.
16. 16. The layered structure according to claim 11, further comprising two protective films, the insulating spacer layer being between one of the protective films and the insulating base material layer, and the conductive layer being between the insulating adhesive layer and the other protective film.
17. 17. The layered structure according to claim 11, which is a layered structure and includes, at a time, a protective film, an insulating separator, an insulating base material layer, an insulating adhesive layer, a conductive layer, and a protective film.
18. 18. The method for producing a layered structure according to any one of claims 11 to 17, characterized by comprising coating the composition according to any one of claims 1 to 5 on one side of an insulating base layer which is not bonded to a conductive layer for forming an insulating barrier layer, and coating a polyamic acid or a composition comprising a polyamic acid for forming the insulating adhesive layer on the other side of the insulating base layer.
19. 19. The method of claim 18, further comprising heat treating the two-sided coated insulating substrate layer.
20. 20. The production method according to claim 19, wherein the heat treatment is to raise the temperature stepwise from 60 to 130 ℃ to 250 to 350 ℃ and the treatment time per temperature interval is 1 to 10 minutes.

Description

Flexible metal sheathing panel and method of making same Technical Field The invention belongs to the technical field of printed circuit boards, in particular to a flexible metal cladding plate and preparation thereof. Background The flexible metal sheathing refers to a laminate composite material formed by bonding a metal foil together on the surface of a polymer insulation film through a certain process. Flexible metal sheathing, such as flexible copper sheathing (FCCL), is a substrate material for printed circuit boards (FPCs), and is widely used in the fields of cellular phones, flat panels, liquid crystal displays, etc. as a base material for manufacturing printed circuit boards by electronic industry processing due to good heat resistance. The flexible metal sheathing board is usually a single-sided flexible metal sheathing board or a double-sided flexible metal sheathing board, which is obtained by coating a thin metal foil conductor satisfying the requirement of flexibility on the surface of an insulating material such as a PI film or a polyester film as a base material. Lamination is one of the most common methods in flexible metal sheathing, such as FCCL manufacturing processes. The process bonds the copper foil to the insulating film by means of an adhesive. When the copper foil and the adhesive (adhesive-coated insulating film) simultaneously pass through the high-temperature and high-pressure environment of the two laminating rolls, the adhesion reaction occurs therebetween, thereby producing the FCCL film. At this time, in order to protect the surface of the flexible copper sheathing panel, a protective film (polyimide film) may be used for protection (a structure of forming the flexible copper sheathing panel/protective film/copper foil/adhesive sheet/copper foil/protective film/flexible copper sheathing panel). The single-sided FCCL is a structure in which copper foil is laminated on one side of a polyimide film, and the double-sided FCCL is a structure in which copper foil is laminated on both sides of a polyimide film. In order to manufacture a single-sided flexible copper clad laminate by using a lamination method, if a conventional protective film with Thermoplastic Polyimide (TPI) coated on both sides is used for lamination operation, the surface of the TPI coating on the single-sided part of the protective film, to which the copper foil is not bonded, may adhere to the surface of the polyimide protective film, which is a material used in the lamination process, so that the single-sided flexible copper clad laminate is difficult to manufacture. To ameliorate these problems, applying a TPI coating with an adhesive on only one side using a single-sided FCCL can result in severe curling (Curl) and thus affect production. Therefore, there is a need for a single-sided flexible copper clad laminate that improves curling during lamination manufacturing. Disclosure of Invention The invention adopts TPI with different components to be respectively applied to the bonding surface and the non-bonding surface area of the metal foil, so as to furthest reduce the bonding force between the non-bonding surface area TPI and the polyimide protective film in the lamination process, thereby avoiding the curling phenomenon of the single-sided flexible copper-clad plate in the lamination method manufacture. In a first aspect, the present invention provides a composition for forming a thermoplastic polyimide comprising a pre-polymerized polyamic acid comprising structural units derived from a dianhydride and a diamine, the thermoplastic polyimide having reduced adhesion. In some embodiments, the thermoplastic polyimide has an adhesion force of <0.3kgf/5 cm. Preferably, the thermoplastic polyimide has an adhesion force of <0.2kgf/5 cm. More preferably, the thermoplastic polyimide has an adhesion force of <0.1kgf/5 cm. In some embodiments, the dianhydride is selected from one or more of PMDA, BPDA, BTDA, ODPA and TMEG and the diamine is selected from one or more of p-PDA, m-PDA, ODA, BAPP, TPE-R, TPE-Q, m-Tolidine, o-Tolidine and DABA. In some embodiments, the thermoplastic polyimide has reduced adhesion to the protective film. In some embodiments, the thermoplastic polyimide has minimal adhesion to the protective film. In some embodiments, the protective film is a polyimide film. In some embodiments, the dianhydride comprises PMDA. In some embodiments, the PMDA comprises 70mol% or more of the dianhydride. Preferably, the PMDA comprises 80mol% or more of the dianhydride. More preferably, the PMDA comprises greater than 90mol% of the dianhydride. In some embodiments, the PMDA comprises 100mol% of the dianhydride. In some embodiments, the diamine comprises one or more of TPE-R, ODA and BAPP. In some embodiments, one or more of the TPE-R, ODA and BAPP comprise greater than 90 mole percent of the diamine. In some embodiments, one or more of the TPE-R, ODA and BAPP comprises 100 mole% of the diamine. In some embodime