Abstract: A polyamide resin pellet for a miniature part, comprising a polyamide resin (A) whose melting point as measured by DSC is in the range of 280 to below 330° C., which has an average volume of 0.001 to 21 mm3, the average volume determined by randomly sampling 50 pellets, measuring the weight and specific gravity of each of the pellets and dividing the weight by the specific gravity. The polyamide resin pellet exhibits low water absorption and is excellent in moldability, mechanical strength characteristics and heat resistance. Further, it has specified average volume, configuration, average diameter and average length, so that, in an injection molding, plasticization is smoothly effected to thereby enable obtaining a molded item or article which exhibits low dispersion of weight and strength and has excellent hue. The polyamide resin pellet is especially suitable for use in a molding material for forming miniature parts for motor vehicles and electrical or electronic equipments.

Abstract: A polyamide resin pellet for a miniature part, comprising a polyamide resin (A) whose melting point as measured by DSC is in the range of 280 to below 330° C., which has an average volume of 0.001 to 21 mm3, the average volume determined by randomly sampling 50 pellets, measuring the weight and specific gravity of each of the pellets and dividing the weight by the specific gravity. The polyamide resin pellet exhibits low water absorption and is excellent in moldability, mechanical strength characteristics and heat resistance. Further, it has specified average volume, configuration, average diameter and average length, so that, in an injection molding, plasticization is smoothly effected to thereby enable obtaining a molded item or article which exhibits low dispersion of weight and strength and has excellent hue. The polyamide resin pellet is especially suitable for use in a molding material for forming miniature parts for motor vehicles and electrical or electronic equipments.

Abstract: A semiaromatic polyamide resin composition comprising: (A) a polyamide copolymer in which a main constituent component unit is a polyamide formed of a recurring unit of a dicarboxylic acid component unit and a diamine component unit, at least not less than 45 mol % of said dicarboxylic acid component unit being a terephthalic acid component unit, and said diamine component unit comprising a straight-chain alkylenediamine component unit and/or an alkylenediamine component unit having a side-chain alkyl group; (B) an aliphatic polyamide containing, a unit derived from a lactam having 12 carbon atoms, a unit derived from an aminocarboxylic acid having 12 carbon atoms or a unit derived from a dodecanoic diacid and a diamine; and (C) a graft-modified product of a graft-modified ethylene/&agr;-olefin copolymer, a graft-modified product of an aromatic vinyl compound/conjugated diene copolymer, or a graft-modified product of a hydrogenated product of the aromatic vinyl compound/conjugated diene copolymer.

Abstract: A semiaromatic polyamide resin composition of the present invention contains a polyamide (A) in which a dicarboxylic acid component unit comprises a terephthalic acid component unit and a diamine component unit comprises a straight-chain alkylenediamine component unit and an alkylenediamine component unit having a side-chain alkyl group; and a modified ethylene/.alpha.-olefin copolymer (B) obtained by graft-modifying an ethylene/.alpha.-olefin copolymer having particular properties with an unsaturated carboxylic acid or a derivative thereof. A molded article obtained by using this composition exhibits excellent anti-creeping property under high-temperature and high-humidity conditions, and causes the metal mold to be little fouled during the molding operation.

Abstract: The semiaromatic polyamide of the invention comprises 40 to 90% by mol of (A) recurring units derived from terephthalic acid and an aliphatic diamine of 4 to 12 carbon atoms, 0 to 50% by mol of (B) recurring units derived from isophthalic acid and an aliphatic diamine of 4 to 12 carbon atoms, 0 to 60% by mol of (C) recurring units derived from an aliphatic dicarboxylic acid of 4 to 18 carbon atoms and an aliphatic diamine of 4 to 12 carbon atoms and 0 to 50% by mol of (D) recurring units derived from a lactam or an aminocarboxylic acid of 6 to 20 carbon atoms, and has a content of boiling water-soluble components (MO components) of not more than 0.25% by weight. The semiaromatic polyamide has a low content of the MO components, so that mold contamination hardly brought about in the molding process, and also molded articles of good heat resistance can be produced.

Abstract: An X-ray film holding apparatus includes front and rear plates through which X-rays transmit. The front and rear plates respectively have opposite surfaces. The front plate is flexible, and the opposite surface of the front plate has a partial spherical portion extending toward the rear plate. The spherical surface is curved along a first direction and a second direction perpendicular to the first direction. The front plate is rectangular, and its three sides are supported by a holding frame. An elastic cushion member is adhered to the opposite surface of the rear plate. The cushion member has a surface opposite to the front plate. The opposite surface of the cushion member has a partial cylindrical surface extending toward the front plate. The cylindrical surface is curved along the first direction and parallel to the second direction. Intensifying screen sheets are respectively adhered to the opposite surfaces of the front plate and the cushion member.

Abstract: An X-ray film holder for holding an X-ray film includes at least one pair of support and intensifying plates each defining mutually opposed inner surfaces. A cushion member is adhesively sandwiched between the opposed inner surfaces of the support plate and intensifying screen. To facilitate removal and/or replacement of the intensifying screen, the cushion member includes protective layers interposed between the cushioned member on the one hand and the support plate and intensifying screen on the other hand. The protective layers thus serve to protect the cushioned member from damage by the adhesive bond while yet permitting bonding release of the cushioned member from the support plate and/or intensifying screen to facilitate removal thereof.

Abstract: Swingable front and back plates are supported by a hinge. Cushion members are pasted individually on the inner surfaces of the front and back plates. The cushion members individually have two-dimensional curved surfaces with the same radius of curvature, and are arranged so that the directions of curvature of their curved surfaces cross substantially at right angles. Intensifying screens curved to match the surfaces of the cushion members are pasted thereon. An X-ray film is sandwiched between the intensifying screens, and the front and back plates are joined together. Thereupon, the region of each cushion member, pressing the X-ray film through its corresponding intensifying screens, extends gradually, moving its center from the hinge side to the free-end side. When the front and back plates are joined together, the X-ray film receives a maximum pressing force from the center of each cushion member. The pressing force decreases with radial distance from the center.

Abstract: In a spot film device, a cassette assembly for a film cassette is mounted for reciprocating in a tunnel between an X-ray exposure position and a position in which the cassette is automatically unloaded or loaded with film. Field defining masks are also mounted for translating selectively with the carriage. The masks are formed of the synthetic materials having minimal X-ray absorption and high rigidity, without an aperture, to define a sharp X-ray field.