LCP extruded film and method for manufacturing the same, LCP extruded film for stretch treatment, LCP stretched film, heat-shrinkable LCP stretched film, insulating material for circuit substrate, and metal foil-clad laminate

Patent metadata

Field	Value
Publication number	US-12447661-B2
Application number	US-202118266228-A
Country	US
Kind code	B2
Filing date	Dec 7, 2021
Priority date	Dec 9, 2020
Publication date	Oct 21, 2025
Grant date	Oct 21, 2025

Abstract

The present invention provides an LCP extruded film comprising a thermoplastic liquid crystal polymer and having a thickness of 15 μm or more and 300 μm or less, wherein coefficients of linear thermal expansion in a MD direction and a TD direction at 23 to 200° C. as measured by a TMA method according to JIS K7197 are each within a range of −30 to 55 ppm/K, and the following conditions
(A) and/or (B) are satisfied, and a method for manufacturing the same, an LCP extruded film for stretch treatment, an LCP stretched film, a heat-shrinkable LCP stretched film, an insulating material for a circuit substrate, and a metal foil-clad laminate: (A) a degree of orientation α 1 (%) of a film surface S 1 exposed and a degree of orientation α 2 (%) of a film surface S 2 located at a depth of 5 μm from the film surface S 1 satisfy a relationship of −4.0≤[(α 2−α1 )/α 1 ]×100≤0.0; (B) a hardness H 1 at a point of a depth of 1 μm located at a position of 1 μm from a film surface in a thickness direction and a hardness H 2 at a thickness center point, as measured by subjecting a film cross section in parallel with a MD direction to a nanoindentation method, satisfy −10.0≤100×(H 2 −H 1 )/H 1 ≤0.0.

First claim

The invention claimed is:

1. An LCP extruded film comprising a thermoplastic liquid crystal polymer and having a thickness of 15 μm or more and 300 μm or less, wherein
the following conditions (A) and/or (B) are satisfied:
(A) a degree of orientation α1 (%) of a film surface S 1 exposed and a degree of orientation x2 (%) of a film surface S 2 exposed by etching treatment in a thickness direction of the film surface S 1 and located at a depth of 5 μm from the film surface S 1 satisfy a relationship of −4.0≤[(α 2 −α 1 )/α 1 ]×100≤0.0, and coefficients of linear thermal expansion in a MD direction and a TD direction at 23 to 200° C. as measured by a TMA method according to JIS K7197 are each within a range of −30 to 55 ppm/K;
(B) a hardness H 1 at a point of a depth of 1 μm located at a position of 1 μm from a film surface in a thickness direction and a hardness H 2 at a thickness center point, as measured by subjecting a film cross section in parallel with a MD direction to a nanoindentation method, satisfy −10.0≤100×(H2−H1)/H1≤0.0, and coefficients of linear thermal expansion in a MD direction and a TD direction at 23 to 200° C. as measured by a TMA method according to JIS K7197 are each within a range of −30 to 55 ppm/K.

2. The LCP extruded film according to claim 1 , wherein the coefficient of linear thermal expansion in the TD direction is 0 to 55 ppm/K.

3. The LCP extruded film according to claim 1 , wherein the film is an intermediate layer obtained by removing both outer layers from a laminated extruded film having the outer layer, the intermediate layer, and the outer layer.

4. The LCP extruded film according to claim 1 , wherein the film surface S 1 does not have any skin layer that is peelable by a tape in an adhesiveness test by a cross-cutting method according to JIS K5600-5-6.

5. The LCP extruded film according to claim 1 , wherein the degree of orientation α 2 of the surface S 2 in the conditions (A) is 37.7 (%) or less.

6. The LCP extruded film according to claim 1 , wherein the degree of orientation α 1 of the film surface S 1 in the conditions (A) is 39.0 (%) or less.

7. The LCP extruded film according to claim 1 , wherein the hardness H 2 at the thickness center point in the conditions (B) is 0.240 (GPa) or more.

8. The LCP extruded film according to claim 1 , wherein the hardness H 1 at the point of a depth of 1 μm in the conditions (B) is 0.250 (GPa) or more.

9. The LCP extruded film according to claim 1 , further containing an inorganic filler.

10. The LCP extruded film according to claim 1 , wherein the LCP extruded film is a T-die extruded film.

11. An insulating material for a circuit substrate, comprising a laminate having at least the LCP extruded film according to claim 1 and a woven fabric provided on at least one surface of the LCP extruded film.

12. A metal foil-clad laminate comprising the LCP extruded film according to claim 1 and metal foil provided on one surface and/or both surfaces of the LCP extruded film.

13. A metal foil-clad laminate comprising a laminate having at least the LCP extruded film according to claim 1 and a woven fabric, and metal foil provided on one surface and/or both surfaces of the laminate.

14. An LCP stretched film comprising a stretched product of the LCP extruded film according to claim 1 .

15. The LCP stretched film according to claim 14 , wherein the stretched product has a stretch ratio (MD direction×TD direction) of 1.3 to 2.5 times to the LCP extruded film.

16. An insulating material for a circuit substrate, comprising a laminate having at least the LCP stretched film according to claim 14 and a woven fabric provided on at least one surface of the LCP stretched film.

17. A metal foil-clad laminate comprising the LCP stretched film according to claim 14 and metal foil provided on one surface and/or both surfaces of the LCP stretched film.

18. A metal foil-clad laminate comprising a laminate having at least the LCP stretched film according to claim 14 and a woven fabric, and metal foil provided on one surface and/or both surfaces of the laminate.

Assignees

• Denka Company Ltd

Inventors

• Masuda Yusuke
• Ogawa Naoki

Classifications

• H05K2201/029

  Woven fibrous reinforcement or textile · CPC title

• C08J2367/04

  Polyesters derived from hydroxy carboxylic acids, e.g. lactones (C08J2367/06 takes precedence) · CPC title

• C08J5/18

  Manufacture of films or sheets · CPC title

• B32B2457/08

  PCBs, i.e. printed circuit boards · CPC title

• B32B2307/536

  Hardness · CPC title