Kuraray Co., Ltd.

Tadao Yoshikawa

Minoru Onodera

Tatsuya Sunamoto

Takahiro Miyata

Katsunori Hatashi

Toshiaki Sato

Shiro Nagata

Takeichi Tsudaka

Tokuo Ikari

Toshinori Tsugaru

Kyoko Okamoto

Tatyuya Sunamoto

A metal-clad laminate excellent in isotropy, appearance, bondability between a TLC polymer film and a metallic sheet, and dimensional stability is provided less costly with a first step of thermally compressing the film with the metallic sheet by passing them through a nipping region between heating rolls, and a second step of heat-treating the resultant metal-clad laminate at a temperature not higher than the melting point of the film, wherein the film has thermal expansion coefficient &#x3b1;satisfying &#x3b1;=&#x3b2;T+&#x3b3; with thickness T, thickness coefficient &#x3b2; and anisotropy coefficient &#x3b3; of the film; wherein the coefficient &#x3b2; is within the range of &#x2212;0.08 to &#x2212;0.01; the coefficient &#x3b3; is within the range of &#x3b1;+6&#x2266;&#x3b3;&#x2266;&#x3b1;+10 with thermal expansion coefficient &#x3b1;of the metallic sheet; and thermal expansion coefficient &#x3b1;of the film is within &#x3b1;&#x2212;2&#x2266;&#x3b1;&#x2266;&#x3b1;+3 with the coefficient &#x3b1;.

Metal-clad laminate and method for production thereof

The object of the invention is to provide a wiring board having the uniform quality at a high yield which is produced by hot-pressing and laminating on a wiring board base material a thermotropic liquid crystal polymer which is excellent as a wiring board covering material. The present invention provides a method of making a wiring board comprising: hot-pressing and laminating a thermotropic liquid crystal polymer film on a wiring board base material on the surface of which at least one layer containing a electro-conductive circuit is exposed, characterized by that a viscoelastic characteristic of the thermotropic liquid crystal polymer film is measured at a low frequency within a laminating temperature region and the hot-pressing is carried out at a temperature selected so that the viscoelastic characteristic falls within a predetermined range.

Method of making wiring boards covered by thermotropic liquid crystal polymer film

A method of making a multi-layer circuit board that has a first film and at least two more films, second and third films, each being made of a thermoplastic polymer capable of forming an optically anisotropic melt phase, the first film having a low melting point, the second and third films having respective melting points higher than the melting point of the first film and at least one of the second and the third films having a circuit pattern thereon, and the first to third films are thermo compressed together with the first film interposed between the second and third films. This method entails causing at least one of the circuit patterns on one of the second and third films to contact an opposing surface of the other of the second and third films through the first film during the thermo compression bonding of the first to third films.

Multi-layer circuit board and method of making the same

The method of manufacturing a film of thermotropic liquid crystal polymer includes extruding a thermotropic liquid crystal polymer of a kind in which any one of activation energies Ea1 and Ea2 of a melt viscosity is within the range of 30 to 90 kcal/mol, with the ratio (Ea1/Ea2) of the activation energy Ea1 relative to the activation energy Ea2 being within the range of 1 to 1.7. The activation energies Ea1 and Ea2 are measured by means of a capillary rheometer, including a nozzle of 1 mm in inner diameter and 10 mm in length disposed at an angle of introduction of 90&#xb0; and a barrel of 9.55 mm in inner diameter, at respective shear rates of 243 secondsand 2432 secondsunder a temperature ranging from the temperature [(Tm&#x2212;10)&#xb0; C.], which is lower by 10&#xb0; C. than the melting point [(Tm)&#xb0; C.] of the thermotropic liquid crystal polymer, to the temperature [(Tm+20)&#xb0; C.], which is higher by 20&#xb0; C. than the melting point [(Tm)&#xb0; C.] of the thermotropic liquid crystal polymer. The thermotropic liquid crystal polymer also has a melt viscosity of not lower than 400 poises measured under predetermined conditions, and is extruded from a die that is heated to a temperature of predetermined range.

Film forming method

An apparatus for making an inflation film formed by extruding a raw resin in a molten state through a circular die to form a tubular film, and expanding the tubular film by the pressure of a gaseous medium introduced into an inner space thereof, while the tubular film is being cooled. The apparatus includes a cooling ring, at least one air ring coaxial with the circular die, and an adjusting device for adjusting the temperature of a gaseous medium, blown from the air ring, to a range effective to retain the tubular film, then still in a molten phase, in a condition in which the tubular film is inflated. A method for making an inflation film is also disclosed.

Apparatus for and method of making inflation films

An inflation film is formed by extruding a raw resin in a molten state through a circular die to form a tubular film, expanding the tubular film by the pressure of a gaseous medium introduced into an inner space of the tubular film, while the tubular film is being cooled to be solidified by blowing a cooling gas to the outer surface of the tubular film, and drawing the film while being progressively flattened by guide members. During the manufacture, the temperature Tf (&#xb0; C.) of the solidified tubular film at the time it contacts the guide member for the first time is so adjusted as not to be higher than Tr (5) [&#xb0; C.]; wherein Tr (5) represents the temperature at which the thermal deformation ratio of the solidified tubular film becomes 5% when it is measured, being loaded with a stress of a value equal to the frictional force received from the guide members under the conditions of manufacture of the film.

Method for making inflation films

To continuously produce a metal laminate having excellent dimensional stability and flatness, there is provided with a method of producing a metal laminate in which a thermoplastic liquid crystal polymer film (') capable of forming an optically anisotropic melt phase is heat-treated on a heat treatment roll having unevenness () on its surface and subsequently a metal sheet () is bonded to at least one side of the film (&#x2032;).

Method for producing metal laminate

A method of producing a metal laminate for a circuit board includes a first step of press-bonding a thermotropic liquid crystal polymer film having a segment orientation ratio SOR within a range not smaller than 0.90 and smaller than 1.15 along the longitudinal direction of the film, to a metal sheet between hot rolls while the thermotropic liquid crystal polymer film is in a tense or non-tense state; and a second step of heating the laminate obtained in the first step to a temperature not lower than the melting point of the thermotropic liquid crystal polymer film.

Metal laminate for a circuit board

Optical information recording medium that has resistance to scratching, resistance to friction static electricity, rapid discharging, resistance to dust adhesion on surface, thus having high reliability. The optical information recording medium has one or more substrates and one or more recording layers, and, respectively, one or more hardening coats and one or more antistatic coats provided on one or two sides of the optical information recording medium.

Optical information recording medium

An optical information recording medium, comprising a substrate and a recording layer, the recording layer containing a metal complex of a monoazo compound of the formula: ##STR1## wherein X is a residue which, taken together with the adjacent nitrogen atom and carbon atom, forms a heterocyclic ring; Y is a residue which, taken together with the two adjacent carbon atoms, forms an aromatic ring; and Z is hydroxy or carboxy.

Growing community of inventors

Kurashiki, Japan

Tadao Yoshikawa