Flexible laminated board and multilayer circuit board

A method for manufacturing a flexible laminated sheet consisting of an insulation film formed of a liquid crystal polymer and a metal foil provided on one or both sides of the insulation film, the method comprising steps of:

• continuously feeding the insulation film and the metal foil between a pair of two endless belts;
• and
• thermocompression-bonding the insulation film onto the metal foil by applying heat and pressure to the insulation film and the metal foil between the endless belts to form a flexible laminated sheet, wherein
• the step of thermocompression bonding comprises:
• heating the flexible laminated sheet so that a maximum temperature of the flexible laminated sheet is in a range from a temperature that is 45° C. lower than a melting point of the liquid crystal polymer of the insulation film to a temperature that is 5° C. lower than the melting point, and
• cooling the flexible laminated sheet under the pressure between the endless belts so that an exit temperature, which is a temperature of the flexible laminated sheet when transferred out of the endless belts, is in a range from a temperature that is 235° C. lower than the melting point of the liquid crystal polymer of the insulation film to a temperature that is 100° C. lower than the melting point.