COMPOSITE FILMS FOR MOBILE ELECTRONIC DEVICE COMPONENTS

1 . A composite film (CF) having a thickness (T) of less than 0.20 mm, and comprising:

a fiber fabric (FF) selected from the group of glass or quartz fiber fabric; and

a composition (C) comprising at least one fluoropolymer (FP) coated on a surface of the fiber fabric (FF);

wherein the fiber fabric (FF) is woven and wherein the fluoropolymer (FP) comprises:

recurring units derived from tetrafluoroethylene (R TFE );

recurring units (R F ) derived from a fluoromonomer (F) selected from the group of perfluoro(alkyl vinyl ether)s (PAVE), hexafluoropropylene (HFP) and combination of two or more of said fluoromonomers; and

recurring units (R M ) derived from at least one monomer (M) selected from the group consisting of (i) monomers comprising a functional group (FG) selected from the group consisting of an hydroxy group, an isocyanate group, a carboxylic acid group and an anhydride group, (ii) chlorotrifluoroethylene (CTFE) and (iii) dichlorodifluoroethylene (R1112); and

with the following proportions expressed in mol %:

(R TFE ): at least 75.0 mol %;

(R F ): between 0 and 20.0 mol %; and

(R M ): between 0.01 to 5.0 mol %;

these proportions in mol % being based on a total amount of moles of recurring units of the fluoropolymer (FP).

2 . A composite film (CF) having a thickness (T) of less than 0.20 mm, and comprising or consisting of, in that order:

a layer (L1) of a composition (C);

a fiber fabric (FF) selected from the group of glass fiber fabric or quartz fiber fabric; and

a layer (L2) of composition (C);

wherein composition (C) comprises at least one fluoropolymer (FP) in contact with at least one surface of the fiber fabric (FF); and

wherein the fiber fabric (FF) is woven and wherein the fluoropolymer (FP) comprises:

recurring units derived from tetrafluoroethylene (R TFE );

recurring units (R F ) derived from a fluoromonomer (F) selected from the group of perfluoro(alkyl vinyl ether)s (PAVE), hexafluoropropylene (HFP) and combination of two or more of said fluoromonomers; and

recurring units (R M ) derived from at least one monomer (M) selected from the group consisting of (i) monomers comprising a functional group (FG) selected from the group consisting of an hydroxy group, an isocyanate group, a carboxylic acid group and an anhydride group, (ii) chlorotrifluoroethylene (CTFE) and (iii) dichlorodifluoroethylene (R1112); and

with the following proportions expressed in mol %:

(R TFE ): at least 75.0 mol %;

(R F ): between 0 and 20.0 mol %; and

(R M ): between 0.01 and 5.0 mol %;

these proportions in mol % being based on a total amount of moles of recurring units of the fluoropolymer (FP).

3 . (canceled)

4 . The composite film (CF) according to claim 1 , wherein the proportion of recurring units (R M ) in the fluoropolymer (FP) is:

between 0.05 and 5.0 mol % or between 0.05 and 3.0 mol %; and/or

at most 1.5 mol % or at most 1.0 mol %.

5 - 7 . (canceled)

8 . The composite film (CF) according to claim 1 , wherein the fluoromonomer (F) is selected from the group of perfluoro(alkyl vinyl ether)s (PAVE) of generic formula CF 2 ═CFOR f (I) wherein R f is a C 1 -C 8 perfluoroalkyl group.

9 . The composite film (CF) according to claim 1 , wherein monomer (M) is selected from the group consisting of CTFE, R1112, itaconic anhydride, citraconic anhydride and 5-norbornene-2,3-dicarboxylic anhydride (NAH).

10 . The composite film (CF) according to claim 1 , wherein the fluoropolymer (FP) is a copolymer comprising recurring units from TFE, at least one perfluoro (alkyl vinyl ether) (PAVE) and at least one monomer (M) comprising an anhydride group, with the following proportions:

(R TFE ): at least 95.5 mol %;

(R PAVE ): between 1.0 and 3.0 mol %;

(R M ): between 0.08 and 1.5 mol %.

11 . The composite film (CF) according to claim 1 , wherein a melting temperature (Tm) of the fluoropolymer (FP) is at least 280° C.

12 . The composite film (CF) according to claim 1 , wherein melt flow rate (MFR) of the fluoropolymer (FP) measured according to ASTM D1238 (372° C.; 5 kg) is at least 1.0 g/10 min.

13 - 16 . (canceled)

17 . The composite film (CF) according to claim 1 , wherein the fiber fabric (FF) has an average area weight (in grams per square meter or g/m 2 ) comprised between 10 g/m 2 and 100 g/m 2 .

18 . The composite film (CF) according to claim 1 , exhibiting at least one of the following dielectric constant Dk at 5 GHz as measured by Split Post Dielectric Resonator (SPDR), IEC 61189-2-721:2015:

after drying 1 h at 100° C.

equal to or less than 3.0

and/or

after immersion in water for

equal to or less than 3.0

24 hours

and/or

after leaving the film 1 day at

equal to or less than 3.0

room temperature in an

atmosphere with 50%

relative humidity

19 . The composite film (CF) according to claim 1 , exhibiting at least one of the dissipation factors Df at 5 GHz as measured by Split Post Dielectric Resonator (SPDR), IEC 61189-2-721:2015:

after drying 1 h at 100° C.

equal to or less than 0.0020

and/or

after immersion in water for

equal to or less than 0.0020

24 hours

and/or

after leaving the film 1 day at

equal to or less than 0.0020

room temperature in an

atmosphere with 50%

relative humidity

20 . The composite film (CF) according to claim 1 , exhibiting at least one of the following dielectric constants Dk at 20 GHz as measured by Split Cylinder Resonator, IPC TM-650 2.5.5.13:

after drying 1 h at 100° C.

equal to or less than 3.0

and/or

after immersion in water for

equal to or less than 3.0

24 hours

and/or

after leaving the film 1 day at

equal to or less than 3.0

room temperature in an

atmosphere with 50%

relative humidity

21 . The composite film (CF) according to claim 1 , exhibiting at least one of the following dissipation factors Df at 20 GHz as measured by Split Cylinder Resonator, IPC TM-650 2.5.5.13:

after drying 1 h at 100° C.

equal to or less than 0.0030

and/or

after immersion in water for

equal to or less than 0.0028

24 hours

and/or

after leaving the film 1 day at

equal to or less than 0.0028

room temperature in an

atmosphere with 50%

relative humidity

22 . (canceled)

23 . The composite film according to claim 1 , exhibiting a folding endurance equal to or greater than 40,000 cycles, measured according to ASTM D2176-16 at 90 cycles/min under a 0.9072 Kg load, 135° angle and a temperature of at 23±2° C.

24 . The composite film according to claim 1 , exhibiting a coefficient of thermal expansion (CTE), in MD or in TD, lower than or equal to 80 ppm/° C. (1 ppm=μm/(m.° C.)).

25 . The composite film according to claim 1 , where warp (f1) or weft fibers (f2) of the fiber fabric (FF) are oriented at an angle α relative to the longitudinal axis of the composite film (CF), α being between 20° and 80°.

26 . The composite film according to claim 1 , wherein the composite film (CF) is according to (i) configuration (composition (C))/fiber fabric (FF)) or (ii) configuration (composition (C))/fiber fabric (FF))/(composition (C)).

27 - 28 . (canceled)

29 . The composite film according to claim 1 , wherein the composite film (CF) is prepared by a method which comprises a) putting into contact the composition (C) on the surface(s) of the fiber fabric (FF) and b) applying pressure and heat to a composite structure obtained after step a).

30 . The composite film according to claim 1 , wherein the composite film (CF) is prepared by a method which comprises the steps of a) putting into contact the composition (C) comprising the fluoropolymer (FP) on the fiber fabric (FF) and b) applying pressure P of at least 0.3 MPa and heating at a temperature T process such that the composition (C) is in a molten form.

31 . (canceled)

32 . Copper-clad laminate (CCL) comprising at least one copper foil and the composite film (CF) according to claim 1 .

33 . Copper-clad laminate (CCL) according to claim 32 , having a configuration (in that order): copper foil/composite film (CF) or a configuration: copper foil/composite film (CF)/copper foil.

34 - 35 . (canceled)