Method for producing laminate

Abstract

A method for producing a laminate, wherein a film comprised of a liquid-crystalline polymer film forming an optically anisotropic molten phase and a metal foil are piled and are passed between pressing rolls, to adhere said film to said metal foil by pressing with heating, which comprises using, as at least one roll of said pressing rolls, a coated roll having a metal roll and, provided on the surface thereof, a coating layer of a resin such as a fluororubber or a polyimide having a thickness of 0.02 to 5 mm, or comprises passing the above polymer film and metal foil between metal pressing rolls together with a heat-resistant film piled on the surface contacting with the metal roll of the polymer film or the metal foil. The method allows the production of a laminate of a liquid-crystalline film and a metal foil exhibiting satisfactory adhesion between them and being excellent in heat resistance, with good productivity.

Description

technical field [0001] The present invention relates to a method for producing a laminate using a film made of a liquid crystal polymer capable of forming an optically anisotropic melt phase (hereinafter referred to as a liquid crystal polymer film). Background technique [0002] Liquid crystal polymer films are known to be excellent materials such as high heat resistance, moisture absorption dimensional stability, and high frequency characteristics. Focusing on the characteristics of liquid crystal polymer films, we are studying the use of such films as insulating materials for circuit boards. When used for circuit boards, a laminate of a liquid crystal polymer film and a metal foil represented by copper foil is suitable as a laminate for wiring boards. [0003] As a technique for producing such a laminate composed of a liquid crystal polymer film and a metal foil, it is possible to enumerate the use of a hot press device in which a liquid crystal pol...

AI Technical Summary

Problems solved by technology

[0006] When only the metal roll of the above 1) is used, since there is no coating layer, uniform pressure cannot be applied, and it is difficult to produce a laminate with good appearance and interlayer peel strength.

On the other hand, when only the rubber roller of the above 2) is used, there is a problem that the means for heating the film as the pressurized body is limited.

That is, in the case of using a rubber roller, although the temperature of the ambient atmosphere is used to adjust the heating of the film or roller, this method is difficult to operate stably because the film is easily broken in the ambient atmosphere.

The combination of rubber rollers and metal rollers is also considered, but in this case, a pair of metal rollers are used to heat the film. When the heat resistance of the rubber is low, the temperature of the film cannot be raised sufficiently, and it is difficult to control the temperature of the rubber roller. As a result, it is difficult to produce a laminate with a sufficiently high adhesive force between the film and the metal foil, which will affect the use of the rubber roll laminate as a printed circuit board that requires the adhesive force of the film and the metal foil, etc. use

In addition, in the above 3) resin-coated metal roller, since the thickness of the coating layer is usually about 10 mm, there is a problem that the temperature difference between the metal roller inside the resin coating layer and the surface of the coating layer increases, or the temperature of the roller surface cannot be raised sufficiently.

[0007] In addition, the method of using double-layer belts for pressurization has the disadvantage that the equipment such as belts is difficult to maintain due to the expensive and large-scale equipment.

Images