The present invention relates to a method for manufacturing a polyimide-based film and a polyimide-based film manufactured thereby and, particularly, to a method for manufacturing a polyimide-based film and a polyimide-based film manufactured thereby, wherein the polyimide-based film is useful as a cover substrate for a flexible electronic device since flexure characteristics thereof, represented by yield elongation, are excellent.

The invention relates to a method for producing a fibre composite body (2), in particular at least a part of a wheel, comprising the following steps: providing a mould (4) having at least one female mould part (6) and one male mould part, introducing a fibrous raw material (8) and a binder (10) into the female mould part (6), activating the binder (10) by an energy input (p, T) into the mould (4) to form a mould element (12) which is open to diffusion, joining together the mould element (12) which is open to diffusion and a preform structure (14), supplying a resin, so that the resin infiltrates at least partially into the mould element (12) which is open to diffusion and into the preform structure (14), and curing the resin, so that in this way the fibre composite body (2) is formed without a boundary layer.

A polyimide film contains fluorinated substituents and cardo structures. The polyimide film exhibits excellent heat-resistance, transparency and mechanical properties. The polyimide film has a glass-transition temperature (Tg) of at least 360° C., a coefficient of thermal expansion (CTE) of 50 ppm/° C. or lower, a modulus of at least 4.0 Gpa, a b* value of 5 or lower and yellowness index of 8 or less. The polyimide film can be used as a display substrate or an optical film in a liquid crystal display (LCD), an organic light-emitting diode (OLED) and in other fields where the characteristic features are required.

A resin composition containing a polyimide resin particle (A) and at least one selected from the group consisting of a thermoplastic resin (B) and a thermosetting resin (C), wherein the polyimide resin particle (A) contains a repeating structural unit represented by the following formula (1) and a repeating structural unit represented by the following formula (2), a content ratio of the repeating structural unit of the formula (1) with respect to the total of the repeating structural unit of the formula (1) and the repeating structural unit of the formula (2) is 20 to 70 mol %, and the polyimide resin particle (A) has a volume average particle size D50 of 5 to 200 μm.

(R.sub.1 represents a divalent group having from 6 to 22 carbon atoms containing at least one alicyclic hydrocarbon structure; R.sub.2 represents a divalent chain aliphatic group having from 5 to 16 carbon atoms; and X.sub.1 and X.sub.2 each independently represent a tetravalent group having from 6 to 22 carbon atoms containing at least one aromatic ring.)

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The method of the present invention for producing a shaped film includes a step of arranging a thermoplastic resin film to divide a space into a first space located on one surface side of the film, and a second space located on the other surface side, a step of heating the thermoplastic resin film, a step of curving the thermoplastic resin film in one space by using a difference in pressure between the first space and the second space, a step of stopping the curving step of the thermoplastic resin film in a state where at least a convex curved surface of both surfaces of the film is exposed into the space, and a step of cooling the curved film.

A portable welding device comprising: a base facing a work surface, designed to receive tapes in electrically conductive composite materials to be joined or defined by at least one already positioned tape; an operating head receiving one tape at a time and movable with respect to the base along at least a first movement line parallel to the work surface; a motorized arm connecting the operating head to the base and selectively activatable to impart movements to the operating head; and feeding means selectively activatable to feed one tape at a time to the operating head and connected to the operating head; the operating head comprises a positioning roller receiving a tape at a time; a pressure roller spaced from and aligned with the positioning roller along the first movement line; and an inductor interposed between the positioning roller and the pressure roller with reference to the first movement line.

A portable welding device comprising: a base facing a work surface, designed to receive tapes in electrically conductive composite materials to be joined or defined by at least one already positioned tape; an operating head receiving one tape at a time and movable with respect to the base along at least a first movement line parallel to the work surface; a motorized arm connecting the operating head to the base and selectively activatable to impart movements to the operating head; and feeding means selectively activatable to feed one tape at a time to the operating head and connected to the operating head; the operating head comprises a positioning roller receiving a tape at a time; a pressure roller spaced from and aligned with the positioning roller along the first movement line; and an inductor interposed between the positioning roller and the pressure roller with reference to the first movement line.

The invention generally relates to shape memory films that are tri-functionally crosslinked and that comprise multiple, non-terminal, phenylethynyl moieties. In addition, the present invention relates methods of fabricating such films. Due to the improved properties of such SMPs, the SMP designer can program in to the SMP thermomechanical property enhancements that make the SMP suitable, among other things, for advanced sensors, high temperature actuators, responder matrix materials and heat responsive packaging.

A method of filling a microcavity with layers of a polymer material includes the following steps: (A) estimating a current vertical position of a bottom of the microcavity (current bottom position); (B) lowering the capillary tube into the microcavity towards the current bottom position; (C) dispensing a polymer composition from a tube outlet of the capillary tube under a dispensing applied pressure until the polymer composition substantially fills the microcavity; (D) curing a work piece including the microcavity and the polymer composition in the microcavity to obtain a current layer of the polymer material; and (E) repeatedly executing steps (A), (B), (C), and (D), until the layers of the polymer material have substantially filled the microcavity.

The invention generally relates to shape memory films that are tri-functionally crosslinked and that comprise multiple, non-terminal, phenylethynyl moieties. In addition, the present invention relates methods of fabricating such films. Due to the improved properties of such SMPS, the SMP designer can program in to the SMP mechanical property enhancements that make the SMP suitable, among other things, for advanced sensors, high temperature actuators, responder matrix materials and heat responsive packaging.