Multilayer board

Patent metadata

Field	Value
Publication number	US-9485860-B2
Application number	US-201514859625-A
Country	US
Kind code	B2
Filing date	Sep 21, 2015
Priority date	Jul 30, 2013
Publication date	Nov 1, 2016
Grant date	Nov 1, 2016

Abstract

In a flexible board including laminated resin layers containing the same thermoplastic resin as a principal material, a rigid portion includes a region in which a first resin layer is disposed between a second resin layer defining an upper principal surface and a third resin layer defining a lower principal surface so that the rigid portion has a large thickness, and a flexible portion includes a region in which the first resin layer is not disposed between the second and third resin layers so that the flexible portion has flexibility, a step portion at which a thickness changes is between the rigid and flexible portions, and the second and third resin layers extend in a region from the rigid portion beyond the step portion to the flexible portion.

First claim

What is claimed is:

1. A multilayer board comprising:
a first resin base material portion;
a second resin base material portion; and
a third resin base material portion; wherein
the first, second and third resin base material portions include a same thermoplastic resin as a principal material and are laminated on each other; wherein
the first resin base material portion defines a first principal surface of the multilayer board;
the second resin base material portion defines a second principal surface of the multilayer board;
the third resin base material portion is provided between the first resin base material portion and the second resin base material portion in a lamination direction of the multilayer board;
a step portion at which a thickness of the multilayer board changes is provided between a flexible portion which has flexibility and in which the third resin base material portion is not disposed and a thick portion in which the third resin base material portion is disposed so that the thick portion has a thickness larger than that of the flexible portion;
the first resin base material portion and the second resin base material portion extend in a region from the thick portion beyond the step portion to the flexible portion;
the first resin base material portion and the second resin base material portion cover both ends of the third resin base material portion in a first direction in which the first resin base material portion and the second resin base material portion extend in a region from the thick portion beyond the step portion to the flexible portion; and
the first resin base material portion and the second resin base material portion are joined directly to one another at outermost ends of the multilayer board in the first direction.

2. The multilayer board according to claim 1 , wherein the first resin base material portion and the second resin base material portion extend over an entire or substantially an entire area of the flexible portion.

3. The multilayer board according to claim 1 , wherein the third resin base material portion includes a plurality of layers which include a plurality of resin base materials.

4. The multilayer board according to claim 3 , wherein the first resin base material portion and the second resin base material portion cover an entirety of an edge portion of the third resin base material portion which includes the plurality of layers which are the plurality of resin base materials.

5. The multilayer board according to claim 1 , wherein
the thick portion is provided at two locations; and
the flexible portion is provided between the thick portions at the two locations.

6. The multilayer board according to claim 5 , wherein the first resin base material portion and the second resin base material portion extend in the first direction of the flexible portion from the thick portion at one side beyond the step portion at the one side, the flexible portion, and the step portion at the other side to the thick portion at the other side.

7. The multilayer board according to claim 1 , wherein the flexible portion has a band shape extending in a lengthwise direction.

8. The multilayer board according to claim 1 , wherein the rigid portion is wider than the flexible portion.

9. The multilayer board according to claim 1 , wherein the rigid portion is thicker than the flexible portion in the lamination direction.

10. The multilayer board according to claim 1 , wherein the first, second and third resin base material portions include one of a liquid crystal polymer resin, a polyether ether ketone resin, a polyether imider resin, a polyphenylene sulfide resin, and a polyimide resin as the principal material.

11. The multilayer board according to claim 1 , further comprising a conductor pattern having a linear shape provided at the flexible portion so as to extend from the thick portion to another thick portion.

12. The multilayer board according to claim 1 , wherein the first, second and third resin base material portions are fused to each other and integral with each other.

13. The multilayer board according to claim 1 , further comprising interlayer connection conductors extending through the first, second and third resin base material portions.

14. The multilayer board according to claim 1 , further comprising planar or substantially planar conductors extending along a surface of each of the first, second and third resin base material portions.

15. The multilayer board according to claim 1 , wherein more resin layers are provided at the thick portion than at the flexible portion.

16. The multilayer board according to claim 1 , wherein at least one of the first, second and third resin base material portions defines an entirety of an upper principal surface of the multilayer board.

17. The multilayer board according to claim 1 , wherein at least one of the first, second and third resin base material portions defines an entirety of a lower principal surface of the multilayer board.

18. The multilayer board according to claim 1 , wherein the flexible portion has an elongated cable shape.

Assignees

• Murata Manufacturing Co

Inventors

• Yosui Kuniaki

Classifications

• H05K2201/0129

  Thermoplastic polymer, e.g. auto-adhesive layer; Shaping of thermoplastic polymer · CPC title

• H05K1/0333

  containing S · CPC title

• H05K3/4691 Primary

  Rigid-flexible multilayer circuits comprising rigid and flexible layers, e.g. having in the bending regions only flexible layers · CPC title

• H05K3/4632

  laminating thermoplastic or uncured resin sheets comprising printed circuits without added adhesive materials between the sheets · CPC title

• H05K1/028

  Bending or folding regions of flexible printed circuits (H05K1/0283 takes precedence) · CPC title