Patent ID: 6274242
Filing Date: 2001-08-14
Classification: B32B,C08J,H05K,Y10T

Abstract:
A method of making a liquid crystal polymer film in which a film comprising a polymer capable of forming an optically anisotropic melt phase (which polymer is hereinafter referred to as a liquid crystal polymer) is, after having been laminated on a base material capable of supporting a shape of the film during heat treatment, heat-treated a number of times in the following manner and the base material is subsequently removed to provide the liquid crystal polymer film:First Heat Treatment:This first heat treatment is carried out at a temperature range of from the thermal deformation temperature Tdef of the polymer film to a temperature lower by .alpha..degree. C. than the melting point Tm of the polymer film before the heat treatment (i.e., Tdef.about.(Tm-.alpha..degree. C.)), until the fusion peak temperature TA of the polymer film being heat-treated, which temperature TA is measured by the use of a differential scanning calorimeter under the atmosphere of nitrogen with temperature increased at a speed of 5.degree. C. per minute, attains a temperature TA.sub.1 which is higher by .beta..degree. C. than the melting point Tm of the polymer film before the heat treatment, wherein .alpha. represents 10 to 35.degree. C. and .beta. represents 5 to 30.degree. C.Second Heat Treatment:This second heat treatment is carried out at a temperature range of from a temperature not lower than the melting point Tm of the polymer film before the heat-treatment to a temperature lower than the fusion peak temperature TA.sub.1 until the fusion peak temperature TA.sub.1 attains a temperature TA.sub.2 that is increased .gamma..degree. C. from the fusion peak temperature TA.sub.1, wherein .gamma. represents 5to 20.degree. C.n-th Heat Treatment:This n-th heat treatment is carried out at a temperature range of from the fission peak temperature TA.sub.n-2 to a temperature lower than the fission peak temperature TA.sub.n-1 until the fusion peak temperature TA.sub.n-1 attains a temperature TA.sub.n that is increased .gamma..degree. C. from the fuision peak temperature TA.sub.n-1, wherein n represents an integer equal to or larger than 3 and .gamma. represents 5 to 20.degree. C.