Abstract: The invention provides a water-soluble prefluxe that can solve problems with a soldering land array having a narrow spacing in that fused solder is likely to cause soldering bridges with defective soldering, a printed circuit board with its film formed thereon, and a surface treatment process for a metal in that circuit. The water-soluble preflus comprises given two different benzimidazoles compound and an iodine-based compound optionally with an amino acid, etc. The invention provides a printed circuit board with a film of that preflux formed thereon, and a surface treatment process for the metal in that circuit.

Abstract: A speaker edge is made of a thermosetting composition consisting of a polyurethane prepolymer and an inactivated solid polyamine as a latent hardener. A gas is dispersed in the thermosetting composition, prior to feed into a mold, so that it can foam and solidify to give the speaker edge. In a method of making the speaker edge, the composition will be injected into a female mold segment heated below the critical thermosetting temperature, foaming the composition. Then placed in the female segment is a male segment heated above the critical temperature, causing the ingredients to react with each other to solidify in the mold.

Abstract: The present invention relates to an epoxy resin composition a cure article thereof, a novel epoxy resin used therein, a polyhydric phenol compound suited for used as an intermediate thereof, and a process for preparing the same. One of the objects to be achieved by the present invention is to exert the heat resistance, the moisture resistance, the dielectric performances and the flame-resistant effect required of electric or electronic materials such as semiconductor encapsulating materials and varnishes for circuit boards in the epoxy resin composition.

Abstract: There is provided an in-oil atomization method wherein a solder is fused and dispersed in a heated particle dispersion medium, the method being featured in that even if the quantity of the particle dispersion medium to be employed is relatively small, fine solder particles can be effectively obtained. Namely, this invention provides a method of manufacturing fine particles, wherein solder is fused in the heated particle dispersion medium to obtain a molten solder, which is then dispersed by means of an agitator to obtain molten solder particles which are subsequently cooled and solidify, the method being characterized in that the above dispersing step is performed in the presence of a particle coalescence-preventing agent. This invention also provides a fine metal particles-containing substance and a paste solder composition.

Abstract: Disclosed is a thermosensitive recording material comprising a sheet-shaped support and a thermosensitive recording layer which is formed on at least one surface of the support and comprises a colorless or light-colored dye precursor and a color developer capable of reacting with the dye precursor and inducing color formation therein upon application of heat thereto, the color developer comprising a compound represented by the following formula (I) or analog thereof: 1

Abstract: There is provided a solder work material for forming solder-coated circuit boards, which is capable of preventing the malfunction of circuit that may be caused to generate by voltage noises that tend to be generated by the volumetrical expansion of the flux residue in a soldered laminated ceramic capacitor, etc. even under the environments where temperatures fluctuate widely (for example, −40° C. to +85° C.), or that may be caused to generate by voltage noises to be generated by the fluctuation of parasitic capacity between circuits which may be caused to generate due to a flux residue. There is also provided a circuit board having a residual film of flux left thereon after the deposition of the solder work material. This solder work material is formed of a solder paste composition or a resin flux-cored solder, both comprising a flux containing, as a resin component, acrylic resin for preventing the generation of voltage noises in electronic devices.

Abstract: A thermosensitive recording material having high whiteness and resistance to color formation under high temperature, high humidity conditions has a thermosensitive colored image-forming layer formed on a substrate sheet and includes a dye precursor, a binder and a color developing agent including a compound of the formula (I) and optionally a compound of the formula (V). R1, R3=unsubstituted or methyl or chlorine-substituted aryl group, R2=at least C3 divalent organic group, R4=at least C3 alkyl, aralkyl or aryloxyalkyl group.

Abstract: An epoxy resin composition comprising: (i) an epoxy resin having a melt viscosity of from 0.1 dPa to 5 dPa at 150 ° C. and having two or more repeating units each comprising: a methylene bond substituted by at least an aromatic ring; and a benzene ring substituted by at least a glycidyloxy group, wherein said aromatic ring is at least one member selected from the group consisting of (a) condensed aromatic rings and (b) combinations of aromatic rings in which two or more aromatic monocycles or condensed aromatic rings are connected directly to each other via a single bond; and (ii) a curing agent.

Abstract: In order to make possible to observe light rays in a wide energy band by reflecting the respective light rays therein, for example those in a region extending from soft X-ray to visible light at high reflection factors, a wide band normal incident telescope comprises a reflecting mirror involving a surface part wherein different types of multilayer films have been formed, respectively, in every regions of predetermined shapes, and reflecting light rays, which were input, by the surface part; and a detector to which the light rays reflected by the surface part are input, and which detects spectrally the light rays thus input.

Abstract: A thermosensitive recording material having high whiteness and resistance to color formation under high temperature, high humidity conditions has a thermosensitive colored image-forming layer formed on a substrate sheet and includes a dye precursor, a binder and a color developing agent including a compound of the formula (I) and optionally a compound of the formula (V).

Abstract: A diaphragm is gained by the co-molded of a dome part, a voice coil junction part, a cone part and a peripheral part through the injection mold of thermoplastic resin. The thickness of the central part of the dome is made great so that the resonance amplitude in this part becomes small. In addition, an annular rib is integrally provided to the voice coil junction part so as to increase the junction strength between the diaphragm and the voice coil bobbin. Thus, the electromagnetic driving force of the voice coil can be effectively transmitted to the diaphragm so that a loud speaker with excellent characteristics can be gained.

Abstract: The present invention relates to a thermosensitive recording material of heat fixing type. The thermosensitive recording material comprises, on a sheet substrate, a subbing layer and a thermosensitive color image-forming layer in this order, the thermosensitive color image-forming layer comprising a colorless or light-colored dye precursor and a color-developer which reacts with the dye precursor to color the precursor when the color-developer is heated, the color-developer being selected such that the color image formed has a high solvent resistance after the coloring, and the subbing layer comprising a color developability reducing substance capable of reducing the color-developing function of the color-developer and having a melting point of 40° C. or higher. According to the present invention, a thermosensitive recording material is provided, which has a good fixing property and particularly an excellent legibility of colored images even after accidental heating.

Abstract: A position sensor comprises a housing (10), a rotor (16) having brushes (36, 36) thereon rotatably mounted in the housing, a base plate (20) mounted to the housing, conductive members (48, 50, 52) on the base plate in electrical connection with the brushes, the base plate (20) forming a cover member for the housing so that an outer surface (47) thereof is exposed to the outside. Such an arrangement results in a position sensor with a reduced number of components having improved heat dissipation characteristics and better reliable electrical connections.

Abstract: A multilayer printed circuit board is obtained by impregnating a base material with a thermosetting resin in to form a prepreg; applying an undercoating agent comprising a terminal-bifunctional linear epoxy resin having an average epoxy equivalent of 450 to 6,000, together with at least one of 2-undecylimidazole, 1-cyanoethy1-2-undecylimidazole or 2,4-diamino-6{2'-undecyl-imidazole(1')}ethyl-s-triazine, or the aforementioned components together with an aromatic polyamine, to at least one circuit side of an interlayer circuit board on at least one side of which a circuit has been formed; and laying the prepreg on at least one side of the undercoating agent-applied interlayer circuit board and subjecting them to laminating.

Abstract: The present invention provides: a solid catalyst which enables a person to simply and efficiently carry out an etherification reaction; and a process by which an ether compound is simply and efficiently produced using the solid catalyst. The solid catalyst is a first solid catalyst comprising at least one rare earth element, or is a second solid catalyst comprising a metallic compound which includes a metal atom and a nonmetal atom bonded to the metal atom, wherein the metallic compound has molecular orbitals including: at least one orbital (L) having an energy of E.sub.L (eV) which satisfies E.sub.LUMO .ltoreq.E.sub.L .ltoreq.(E.sub.LUMO +0.05) wherein E.sub.LUMO is an energy (eV) of the lowest unoccupied molecular orbital around the metal atom; and at least one orbital (H) having an energy of E.sub.H (eV) which satisfies (E.sub.HOMO -0.02).ltoreq.E.sub.H .ltoreq.E.sub.HOMO wherein E.sub.

Abstract: A thermosensitive reversible color-developing and disappearing agent includes an aromatic compound having at least one group of the formula, --SO.sub.2 NHCXNH--, wherein X.dbd.O or S atom, and at least one straight chain alkyl group with 11 or more carbon atoms, and is reactive with a dye precursor in a thermosensitive recording material to thereby record colored images on the recording material upon heating imagewise, and make the colored images disappear upon heating to a temperature lower than the colored image-forming temperature.

Abstract: A thermosensitive recording material having a high whiteness and capable of forming clear colored images with an excellent resistance to oil and plasticizers is provided with a thermosensitive colored image-forming layer formed on a substrate sheet and comprising a substantially colorless dye precursor, a binder and a color-developing agent comprising at least one aromatic compound among the formulae (II), (III) and (IV): ##STR1## wherein X is an oxygen or sulfur atom, A represents a multivalent group, E represents a multivalent group having at least one aromatic cyclic group, and n represents an integer of 2 or more.

Abstract: A thermosensitive recording material having an enhanced color-developing property and a high persistency of the resultant colored images formed thereon, is provided with a thermosensitive colored image-forming layer formed on a substrate sheet and comprising a substantially colorless dye precursor and a color developing agent comprising at least one aromatic compound of the formulae (I) and (II): ##STR1## wherein X and Y are an oxygen or sulfur atom, R.sup.1 is an alkyl, cycloalkyl, alkenyl or alkynyl group or a hetero atom-containing alkyl, cycloalkyl or alkenyl group having at least one hetero atom included in a backbone group thereof, R.sup.2 is an aryl or aralkyl group or a substituted aralkyl group having at least one hetero atom substituent, R.sup.3 is an unsubstituted aralkyl group or substituted aralkyl group having at least one hetero atom substituted in an aliphatic hydrocarbon group thereof, and R.sup.

Abstract: A thermosensitive recording material capable of recording thereon clear colored images having high resistances to oily substances, plasticizers, moisture, and heat and an excellent storage persistency over a long time, comprises a thermosensitive colored image-forming layer formed on a sheet substrate and comprising a colorless dye precursor, a color developing agent, and a binder, the color developing agent comprising at least one compound of the formula (I): ##STR1## and the colored image-forming layer further comprising an additive comprising at least one selected from: (1) aromatic epoxy compounds, (2) aromatic aziridine compounds, (3) aromatic compounds of the formulae (II), (III) and (IV): ##STR2##

Abstract: A thermosensitive recording material, capable of providing colored images having a high resistance to oily substances and plasticizers and an excellent storage persistency for a long time, comprises a thermosensitive colored image-forming layer formed on a sheet substrate and comprising a colorless dye precursor, a color developing agent, a colored image-stabilizing agent comprising an aziridinyl compound and/or an epoxy compound, and an additional colored image-stabilizing agent comprising a primary or secondary amine compound and/or a carboxylic compound having a carboxyl group or --CO--O--CO-- group; the color developing agent preferably comprising a compound of the formula (I): ##STR1## wherein X is an O or S atom, R.sub.1 is an unsubstituted aromatic group, or a substituted phenyl group having a lower alkyl or a halogen atom, and R.sub.2 and R.sub.