Abstract: A laser-marking composition characterized by containing a non-black inorganic lead compound and a resin and a laser-marking method characterized by marking the surface of an object comprising said composition by exposure to laser beams having wavelengths falling in the far infrared regions.

Abstract: A semiconductor wafer 11 is mounted on an elongated member 18, one end of which is rotatable about a transverse axis (14), thereby to distribute a liquid on the upper surface of the wafer more evenly. In order to stabilize the rotation of the elongated member, a second elongated member is preferably attached end-to-end to the elongated member (18) and rotates with it. A counterweight (26) in the second elongated member moves during the rotation such that the distance between the wafer and the central axis and the distance between the center of the counterweight and the axis are substantially equal. The weight distribution is approximately symmetrical about the axis and the structure is dynamically stabilized. The counterweight and the wafer assembly may be moved during rotation by applying air pressure from the source (23) to pistons (13,26) in the two elongated members.

Abstract: A photoresist is coated on a substrate to form a planar surface, thus to form a recessed portions corresponding to a mask of a pattern to be formed in the photoresist layer having planar surface. SiO.sub.2 etc. are deposited into the recessed portions to prepare a mask, thus to form a fine pattern by anisotropic etching. As a result, by films remaining below the recessed portions formed in the photoresist layer having planar surface, a fine pattern is formed.

Abstract: A method of laser marking ceramic materials, glazes, glass ceramics and glasses of any desired form, which comprises applying to the material to be marked a 100 to 10,000 .ANG. thick transparent layer of titanium dioxide, then irradiating said oxide layer with a pulsed laser such that the radiation is directed onto said layer in accordance with the form of the marking to be applied, and using laser light of a wavelength which is sufficiently absorbed by the oxide layer, so that a discolouration of said oxide layer is produced at the irradiated areas.

Abstract: Disclosed are a method for converting radiographic image which comprises the steps of:(a) storing radiation energy-corresponding to a radiographic image in a stimulable phosphor of a panel comprising a stimulable phosphor-containing layer,(b) scanning the layer with a stimulating ray to release the stored energy as a fluorescence, and(c) detecting the fluorescence to form an image, wherein the stimulable phosphor is represented by the following formula:(M.sub.1-x.M.sup.I.sub.x)X.aM.sup.II X'.sub.2.bM.sup.III X".sub.3 :dBwherein M represents either Cs or Rb; M.sup.I represents at least one of alkaline metals selected from the group consisting of Li, Na, K, Rb and Cs; M.sup.II represents at least one divalent meal selected from the group consisting of Be, Mg, Ca, Sr, Ba, Zn, Cd, Cu and Ni; M.sup.

Abstract: The present invention provide a process for producing printed circuit boards which comprises the steps of(a) roughening a surface of a copper layer formed on an insulating board.(b) coating the roughened surface of copper layer with a photo-resist layer containing a sublimable copper-corrosion inhibitor, exposing the resist layer selectively to actinic rays according to a circuit pattern to form, and developing the resulting resist layer, thereby forming plating-resist coats on circuit-negative pattern portions of the copper layer,(c) heat-treating the plating-resist coats,(d) plating chemically the circuit-corresponding portion with copper,(e) removing the plating-resist coats, and(f) removing the copper layer except the circuit-corresponding portion thereof.

Abstract: Near-infrared absorbers which contain phthalocyanine derivatives in which the four benzene rings contained in the molecule independently have 1 to 4 substituents are light and thermal resistant and possess high molar extinction coefficients. Such near-infrared absorbers are useful in optical recording media, near-infrared absorption filters, and liquid crystal display devices.

Abstract: An information recording medium comprising a substrate, and a recording layer formed thereon which comprises (a) a carbon-based material and (b) an optically reversible material whose optical characteristics can be reversibly changed, with the thermal decomposition temperature of the carbon-based material being higher than the melting point of the optically reversible material.

Abstract: The present invention provides an IR-ray absorptive compound having a specific structural formula and an optical recording medium. The IR-ray absorptive compound has excellent characteristics that absorption in the infrared region is large and improved in solvent solubility.In corporation of the IR-ray absorptive compound into a thin film containing an organic coloring matter of an optical recording medium has remarkably improved the storage stability and the light resistance of the medium. Further the high solubility in solvents prevents formation of a solid in the recording layer, whereby the optical recording medium having a low noise level can be obtained.

Abstract: This invention provides an optical information recording medium whose recording thin film is made of three components of GeTe, Sb.sub.2 Te.sub.3 and Sb derived from a GeTe alloy, an Sb.sub.2 Te.sub.3 alloy and excess Sb and which is capable of recording, reproduction and erasure. By this, optical disk files which have a stable cycle characteristic and are practically useful can be realized.

Abstract: Provided is an optical information card having a particular structure. The card is comprised of four different layers, i.e., a card substrate, a recording layer which is formed on one side of the card substrate and which comprises a naphthalocyanine compound, a polyvinyl alcohol coating directly over the information layer, and a transparent protective layer over the polyvinyl alcohol layer. This structure offers a very sensitive and useful optical information card which can be easily manufactured while maintaining the integrity of the information layer, and which permits one to realize the advantage of using a naphthalocyanine information layer in a card format.

Abstract: Provided is a method for preparing polysiloxy containing naphthalocyanine compounds. The method comprises reacting a cyclosiloxane with a nucleophile to open the ring of the cyclosiloxane. The ring opened cyclosiloxane is then reacted with a naphthalocyanine precursor and a capping group compound. The nucleophile can perform the dual role of the nucleophile and the capping group compound. The method permits the preparation of siloxane containing naphthalocyanine compounds in a more proficient manner through the use of cyclosiloxanes as reactants.

Abstract: An optical recording medium such as an optical disk, which is capable of reversibly repeating a recording/erasing cycle. This optical recording medium comprises a transparent substrate and recording layer formed on the substrate. This recording layer comprise a liquid crystalline high polymer having side chains and a dyestuff having a recording-light absorbing property. The side chain may preferably comprises mesogen group, a monocyclic or polycyclic compound such as phenyl, benzyl, naphthyl or anthryl group, and alkyl or aryl group having 1 to 18 carbon atoms.

Abstract: An optical recording element comprising a thin film optical recording layer of an alloy is disclosed. The alloy is represented by the formula Sb.sub.x Te.sub.1-x, wherein x is between about 0.58 and 0.75. The alloys have short erasure times (amorphous to crystalline transition) and excellent environmental stability.

Abstract: An information storage medium consists of a polycarbonate substrate and a recording layer formed on the substrate and containing an AgTe eutectic alloy, carbon, and hydrogen. Information is recorded on the medium by forming pits in the recording layer upon radiation of a laser beam, and is reproduced by radiating a reproducing laser beam onto the recording layer in which the pits are formed and detecting reflectances.

Abstract: An optical information recording medium is disclosed, which comprises a substrate and an organic recording layer formed thereon comprising a polymethine dye and a dithiolate transition metal complex compound having formula (I): ##STR1## wherein R.sup.1, R.sup.2 and R.sup.3 each independently represent hydrogen, a halogen, an alkyl group having 1 to 6 carbon atoms, or a perfluoroalkyl group having 1 to 6 carbon atoms; R.sup.4 and R.sup.5 each independently represent hydrogen, an alkyl group having 1 to 6 carbon atoms, an aryl group or a cyano group, which may form a heterocyclic ring; X represents a cation; M represents a transition metal; n is an integer of 0 to 2, which represents the valence number of the transition metal; and m represents the number of cations, which is an integer of 0 to 2, corresponding to the valence number of the transition metal. Furthermore, novel dithiolate nickel complex compounds for use in the optical information recording medium are disclosed.

Abstract: Provided is an optical information medium which permits the reading and writing of optical information by actively using polarized light. The optical information medium comprises an information layer containing a compound which undergoes a change upon irradiation with circularly polarized light to provide a new product which is optically active, and which is distinguishable from the original compound in its interaction with polarized light. In a preferred embodiment, the optical medium comprises optical isomers which can be selectively photolyzed by circularly polarized light. While writing must be done using a circularly polarized light source, reading of the recorded information can be accomplished using either circularly polarized light or linearly polarized light.

Abstract: A process for making metallized holes in a dielectric substrate which, after galvanic growth of the conductive paths delimited by photoresist on the substrate, includes a drilling step of the substrate and electrogalvanic creation of rivets protruding beyond the edges of the holes on the front of the substrate. The steps of completion of the conductive and resistive paths on the front, deposition of metals on the back, reinforcement of the rivets and galvanic growth of the back and of the metals deposited inside the hole then follow.

Abstract: The present invention relates to an optical recording medium comprising at least one of the following IR-ray absorptive compounds: ##STR1## Incorporation of the IR-ray absorptive compound of the present invention into an optical recording medium noticeably improves the durability of the medium measured by repeated reproduction and light resistance.

Abstract: Printed circuit patterns are photolithographically defined on a three dimensional "projection" surface (204) of a printed circuit substrate (202) using a projection image aligner and a photomask (210) having a planar image (210A). The geometry of the projection is restricted such that the slope of the projection surface, as measured at any point on the projection surface and relative to a reference plane which is parallel to the focal plane of the projection image aligner, is less than 90 degrees. A solution of photoresist includes a photoresist solvent, a fluorosurfactant and an aromatic hydrocarbon solvent, and is preferably sprayed over the projection surface. In one method of manufacture, the printed circuit substrate is moved from one position to another during the exposure of the photoresist layer (206). In another method, after a first portion of the projection surface is exposed by a first photomask (502), a second photomask (504) is substituted and the remainder of the projection surface exposed.