| Patent application number | Description | Published |
|---|
| 20080287642 | Process for Production of Polyimide Film Having High Adhesiveness - A process for the production of non-thermoplastic polyimide film whose precursor solution has high storage stability and which exhibits high adhesiveness even without expensive surface treatment, more specifically, a process fro the production of non-thermoplastic polyimide film made of a non-thermoplastic polyimide containing a block resulting from a thermoplastic polyimide which comprises (A) the step of forming a prepolymer having amino or an acid anhydride group at the end in an organic polar solvent (B) the step of synthesizing a polyimide precursor solution by using the obtained prepolymer, an acid anhydride, and a diamine in such a way as to become substantially equimolar over the whole step, and (C) the step of casting a film-forming dope containing the polyimide precursor solution and subjecting the resultant dope to chemical and/or thermal imidization, wherein the diamine and acid anhydride used in the step (A) are selected so that the reaction of both with each other in equimolar amounts can give a thermoplastic polyimide, and the polyimide precursor obtained in the step (B) is a precursor of a non-thermoplastic polyimide. | 11-20-2008 |
| 20080305316 | Novel Polyimide Film and Use Thereof - The present invention provides a polyimide film and its usage. The polyimide film according to the present invention does not cause dimensional change due to thermal stress. The present invention particularly relates to a polyimide film and its usage, which polyimide film has a characteristic of suppressing thermal deformation of the material in lamination of a polyimide film and a metal layer by a laminate method. The polyimide film according to the present invention has the following characteristics:
| 12-11-2008 |
| 20080305346 | Adhesive Film and Use Thereof - Disclosed in an adhesive film which enables to obtain a flexible metal clad laminate which is suppressed in dimensional change when produced by heat roll lamination. Such an adhesive film comprises a heat-resistant layer containing a highly heat resistant polyimide and an adhesive layer which is formed on at least one surface of the heat-resistant layer and contains a thermoplastic polyimide. In this adhesive film, the thermal shrinkage ratio in the TD direction is not less than +0.01%, and the thermal shrinkage ratio in the MD direction is not more than −0.02%. Consequently, when a metal layer and the adhesive film are bonded together by heat roll lamination and the resulting laminate is subjected to a treatment with heating, occurrence of dimensional changes can be sufficiently suppressed. | 12-11-2008 |
| 20090011223 | Polyimide Film and Method for Production Thereof - Disclosed is a polyimide film which is free from coarse particles caused by aggregation of a filler, therefore, can avoid abnormal electrical discharge during a discharge treatment, repelling during application of an adhesive, and the like. Also disclosed is a method for production of the polyimide film. The method for production of the polyimide film is characterized by using an organic solvent solution containing an inorganic filling material and a first polyamic acid, wherein the organic solvent solution containing the first polyamic acid is prepared by a process comprising the steps of: 1) preparing a dispersion solution which contains the inorganic filling material and a second polyamic acid and has a viscosity of 50 to 500 poises; 2) filtering the dispersion solution; 3) mixing a prepolymer solution containing the first polyamic acid in the process of being polymerized and having a viscosity of 100 poises or lower with the filtered dispersion solution; and 4) increasing the viscosity of the mixed solution to a level ranging from 1000 to 6000 poises. | 01-08-2009 |
| 20090011231 | Adhesive Sheet and Copper-Clad Laminate - Disclosed is an adhesive film having high dimensional stability which can be suitably used for two layer FPCs. Specifically, disclosed is an adhesive sheet composed of an insulting layer and an adhesive layer arranged on one side or both sides of the insulating layer. This adhesive sheet is characterized in that the insulating layer has a ratio E′2/E′1 between the storage elasticity modulus E′1 at 25° C. and the storage elasticity modulus E′2 at 380° C. of not more than 0.2 and a coefficient of thermal expansion in the MD direction of 5-15 ppm at 100-200° C. It is further characterized in that the change in the coefficient of thermal expansion of the adhesive sheet at 100-250° C. after heat treatment at 380° C. for 30 second under tension of 20 kg/m is not more than 2.5 ppm in the tension direction and not more than 10 ppm in the direction perpendicular to the tension direction. | 01-08-2009 |
| 20090069531 | Polyimide Film - A polyimide film which, when used in FPC production, is reduced in dimensional change during the production steps. In particular, a metal-clad laminate apt to have abnormal parts such as rumples is produced from the film, and an FPC reduced in dimensional change is obtained in high yield. The polyimide film has a tan δ peak temperature within a range of 320° C. or more and lower than 380° C. in measuring a dynamic viscoelasticity, and is characterized by having a maximum sag of 13 mm or less. | 03-12-2009 |
| 20090155610 | Heat-resistant adhesive sheet - It is an object of the present invention to provide a heat-resistant adhesive sheet for suppressing fluctuation in dimensional stability of a flexible printed board or, in particular, of a two-layer flexible printed board which has recently been increasingly demanded and which is required to be more highly heat-resistant and reliable. The foregoing problems can be solved by a heat-resistant adhesive sheet having a heat-resistant adhesive layer, containing a thermoplastic polyimide, which is provided on at least one surface of an insulating layer containing a non-thermoplastic polyimide, the heat-resistant adhesive sheet having a stretching of not more than 10 mm at one side thereof. | 06-18-2009 |
| 20090197110 | Novel polyimide film and adhesive film and flexible metal-clad laminate both contained with the same - A polyimide film which, especially when superposed on a metal layer by the laminating method, has the function of diminishing the thermal distortion to be imposed on the material; an adhesive film and a flexible metal-clad laminate each comprising or obtained with the polyimide film. the polyimide film is obtained by reacting an aromatic diamine with an aromatic acid dianhydride and imidiating the polyamic acid obtained, and has a storage elastic modulus in a specific range. | 08-06-2009 |
| 20110033682 | MULTILAYER POLYIMIDE FILM, LAMINATE, AND METAL-CLAD LAMINATE - An object of this invention is to provide a polyimide film suitable for use in flexible printed circuit boards and the like which have high flexibility and dimensional stability, and to provide a laminate and metal-clad laminate which uses such a polyimide film. This invention relates to a multilayer polyimide film being a polyimide film having a multilayer structure, including: a core layer; and clad layers provided on each side of the film, which clad layers are exposed, the core layer being a non-thermoplastic polyimide having an average coefficient of linear expansion at a temperature from 100° C. to 200° C. in a range of 5 ppm/° C. to 20 ppm/° C., each of the clad layers being a polyimide having a peeling strength of 3 N/cm or less, the film as a whole having an average coefficient of linear expansion at a temperature range of 100° C. to 200° C. in a range of 9 ppm/° C. to 30 ppm/° C., and (a)>(b), where (a) is an average modulus of elasticity of the core layer and (b) is an average modulus of elasticity of the clad layers. | 02-10-2011 |
