Abstract: A DVD recorder is provided in which access control is effected by a driver layer (41), a UDF file system layer (42,) that reads and writes data from and to a DVD-RW with reference to a file system, and a data base layer (43) that accesses the UDF file system layer (42) with reference to content management information for management of contents stored in the DVD-RW. The data base layer (43) reads TMP_VMGI which is intermediate-state management information for the DVD-RW, and provisionally registers a file system into the UDF file system layer (42) with reference to information included in the TMP_VMGI. Thus, a file system is provisionally formed even if the DVD-RW loaded in the DVD recorder is in the intermediate state having no file system recorded therein.

Abstract: The object of the invention is to prevent interference fringes of images and allow precise measurement of the thickness of a layer by the optical interferometry by limiting the surface roughness of a conductive substrate. The surface roughness of the conductive substrate provided in an electrophotographic photoreceptor is such that the maximum peak-to-valley roughness height (Ry)=0.8 to 1.4 ?m, the centerline average roughness (Ra)=0.10 to 0.15 ?m, the ten-point average roughness (Rz)=0.7 to 1.3 ?m, the average peak-to-peak distance (Sm)=5 to 30 ?m, and the peak count Pc=60 to 100. In such an electrophotographic photoreceptor, light for exposure can be scattered to an appropriate extent, so that interference fringes can be prevented, and an interference pattern is formed during measurement of the thickness of the photosensitive layer by the optical interferometry so that the thickness of the layer can be measured with a high precision.

Abstract: A multiple number of image forming stations are provided for multiple development colors including black. Each station having a photoreceptor. Each one of the photoreceptors has a charge transport layer including a binder resin that is a blend of at least two kinds of resins. The blended ration of at least two kinds of binder resins for the photoreceptor for black is made different from that of the binder resins for the photoreceptors for the other development colors. The photoreceptor for black presents a greater abrasion resistance than the photoreceptors for the other development colors. This structure makes it possible to use all the photoreceptors for back and colors, for and within, a concurrent period.

Abstract: A supervisory control system including a control unit to which an object load is connected and an operation unit, both being connected to each other via a communication line. The object loads can be controlled according to desired various patterning control by sending out a control request signal to the communication line by the operation of the operation unit, a supervisory unit and an operation display unit, which have been developed for use in the supervisory control system. The operation unit, the supervisory unit and the operation display unit are so constructed as to constitute multi stage connection, thus in an application of these units in the manner of multi stage connection, they are easily available for a large scale supervisory control system with many object loads.

Abstract: An electrophotographic photoreceptor, in which the increase of VL is controlled below 15 V by controlling the content ratio M (ppm) of a charge transporting material CTM2 to a charge transporting material CTM1 within a specific range, wherein the ionization potential Ip(2) of the CTM2 is smaller than the ionization potential Ip(1) of the CTM1 in the constituent of the photosensitive layer, and thereby the electrophotographic photoreceptor has only a little reduction of image concentration. A method for producing an electrophotographic photoreceptor having ?VL which is controlled below 15 V, wherein, in a case where the ionization potential of the charge transporting material used in the previous run of production is small, ?VL can be set below 15 V by using, in the next production, a dip coating liquid, which comprises, as a constitutive material, a charge transporting material in which the difference between the ionization potential of the current material and that of the previous material is set below 0.

Abstract: An electrophotographic color image forming apparatus including a multiple number of photoreceptors for multiple development colors including black, is constructed such that the photoreceptors satisfy the following relation: 0.5<(X/Y)<0.8, where X represents the reduction in film thickness (?) per 1×107 mm of the traveling distance of the photoreceptor for black development and Y represents the reduction in film thickness (?) per 1×107 mm of the traveling distance of the photoreceptors for the other development colors. This limitation is aimed at differentiating the abrasion resistance of the photoreceptors between that for black and that for colors and designating the reduced amounts of the film thickness per unit traveling distance to fall within the predetermined ranges, whereby it is possible to prevent the drum for black development, which is used most frequently, alone, from being worn away at an earlier time.

Abstract: A DVD recorder is provided in which access control is effected by a driver layer (41), a UDF file system layer (42) that reads and writes data from and to a DVD−RW with reference to a file system, and a data base layer (43) that accesses the UDF file system layer (42) with reference to content management information for management of contents stored in the DVD−RW. The data base layer (43) reads TMP_VMGI which is intermediate-state management information for the DVD−RW, and provisionally registers a file system into the UDF file system layer (42) with reference to information included in the TMP_VMGI. Thus, a file system is provisionally formed even if the DVD−RW loaded in the DVD recorder is in the intermediate state having no file system recorded therein.

Abstract: The object of the invention is to prevent interference fringes of images and allow precise measurement of the thickness of a layer by the optical interferometry by limiting the surface roughness of a conductive substrate. The surface roughness of the conductive substrate provided in an electrophotographic photoreceptor is such that the maximum peak-to-valley roughness height (Ry)=0.8 to 1.4 &mgr;m, the centerline average roughness (Ra)=0.10 to 0.15 &mgr;m, the ten-point average roughness (Rz)=0.7 to 1.3 &mgr;m, the average peak-to-peak distance (Sm)=5 to 30 &mgr;m, and the peak count Pc=60 to 100. In such an electrophotographic photoreceptor, light for exposure can be scattered to an appropriate extent, so that interference fringes can be prevented, and an interference pattern is formed during measurement of the thickness of the photosensitive layer by the optical interferometry so that the thickness of the layer can be measured with a high precision.

Abstract: An electrophotographic image forming apparatus according to the present invention includes: a multiple number of image forming stations for multiple development colors including black, each station having a photoreceptor, an exposure device, a developing device for developing each static latent image with the toner of each development color; a recording media conveyer belt conveying, along the photoreceptors, a recording medium on which a monochrome toner image is formed or a color image is formed by overlapping multiple colors of toner images, wherein each of the photoreceptors has a charge transport layer composed of a binder resin that is a blend of at least two kinds of resins, the blended ratio of at least two kinds of binder resins for the photoreceptor for black is made different from that of the binder resins for the photoreceptors for the other development colors so that the photoreceptor for black presents a greater abrasion resistance than the photoreceptors for other development colors.

Abstract: An electrophotographic color image forming apparatus including a multiple number of photoreceptors for multiple development colors including black, is constructed such that the photoreceptors satisfy the following relation:—

Abstract: An electrophotographic photoreceptor, in which the increase of VL is controlled below 15 V by controlling the content ratio M (ppm) of a charge transporting material CTM2 to a charge transporting material CTM1 within a specific range, wherein the ionization potential Ip(2) of the CTM2 is smaller than the ionization potential Ip(1) of the CTM1 in the constituent of the photosensitive layer, and thereby the electrophotographic photoreceptor has only a little reduction of image concentration.

Abstract: To determine whether a record medium loaded on a drive has character information in a management area of the record medium corresponding to data received from the drive and to obtain the character information when the record medium has the character information as the determined result. A system includes an optical disc drive and a host computer 53 connected through an interface 42, wherein the drive has a servo and signal processing portion 30, a system controller 41, and a CD-ROM signal processing portion 50. The servo and signal processing portion 30 reproduces data from a disc 21. The system controller 41 controls the entire operation of the drive. Return data is sent from the drive to the host computer 53 corresponding to a read table of contents (TOC) command received from the host computer 53. A code that represents the data length is contained in a header of the return data. With the code, it is determined whether or not the disc 21 is a CD-TEXT disc.

Abstract: A supervisory control system including a control unit to which an object load is connected and an operation unit, both being connected each other via a communication line, in which object load can be controlled according to desired various patterning control by sending out a control request signal to the communication line by the operation of the operation unit, an operation unit, a supervisory unit and an operation display unit, those have been developed for use in the supervisory control system. The operation unit, the supervisory unit and the operation display unit are so constructed as to constitute multi stage connection, thus in an application of these units in a manner of multi stage connection, they are easily available for a large scale supervisory control system with large many object loads.

Abstract: An electrophotographic photosensitive element is provided with a photosensitive layer containing a charge generating substance and a charge transport substance on a conductive support. X-type metal-free phthalocyanine and a disazo compound are contained as a charge generating substance. With the photosensitive element, sufficient sensitivity is achieved so as to cause virtually no problem, and it is possible to reduce possibility of causing an instable electrostatic property such as a reduction in a charge potential and an increase in a remained potential, even in the case of frequent reuse.

Abstract: The object of the invention is to provide a highly characteristic and lesser defective image using an electrophotographic photoreceptor which can be produced with a better coating property and which is highly sensitive and hardly loses the electrostatic stability during repeated use. A water-soluble or water/alcohol-soluble polyvinyl acetal and an inorganic pigment are involved in an underlayer provided between a conductive support and a photoconductive layer. Particularly, it is favorable to use titanium oxide as the inorganic pigment, make the ratio of polyvinyl acetal/titanium oxide 1/9-9/1 by weight, make the underlayer 0.5-5 .mu.

Abstract: Highly sensitive and highly durable electrophotographic photoreceptors which generate faultless images can be produced by forming the under-coating layer on the conductive support and forming the photoreceptive layer on the layer. The under-coating layer contains dendritic titanium oxide. The under-coating layer contains the dendritic titanium oxide of which the surface is coated with (a) metal oxide(s) and/or (an) organic compound(s). The photoreceptive layer contains a phthalocyanine pigment, and the under-coating layer contains dendritic or needle-like titanium oxide of which the surface is coated with (a) metal oxide(s) and/or (an) organic compound(s). The photoreceptive layer contains a phthalocyanine pigment, and the under-coating layer contains dendritic or needle-like titanium oxide, of which the surface is coated with (a) metal oxide(s) and/or (an) organic compound(s), and an alcohol soluble polyamide resin.

Abstract: An object of the invention is to provide a highly characteristic image using an electrophotographic photoreceptor of which a charge-generating layer can be produced with a better coating property and which is highly sensitive and electrostatically highly stable in repeated use. The charge-generating layer of a function-separated type photoreceptor contains a n-type non-metallic phthalocyanine and a copolymer of vinyl chloride-vinyl acetate type. Particularly, the ratio of the .tau.-type non-metallic phthalocyanine to the copolymer of vinyl chloride-vinyl acetate type is fixed at 1/3-3/1 by weight. The thickness of the charge-generating layer is fixed at 0.1-0.6 .mu.m. As the copolymer of vinyl chloride-vinyl acetate type, copolymers of vinyl chloride-vinyl acetate, vinyl chloride-vinyl acetate-maleic acid, or vinyl chloride-vinyl acetate-vinyl alcohol are selected. Particularly, it is favorable to select those containing at least 10% by weight of the vinyl alcohol component.

Abstract: An object of the present invention is to improve the storage stability of a coating liquid for forming a photosensitive layer of a photosensitive member for electrophotography as well as to improve the electrophotography properties of a photosensitive member produced by applying the coating liquid. A photosensitive member for electrophotography is produced by applying a coating liquid composition for a photosensitive member for electrophotography prepared by dissolving or dispersing an organic photoconductive compound and a binder resin in a solvent, and further containing an aliphatic unsaturated hydrocarbon on an electroconductive substrate, and drying for forming a photosensitive layer on the electroconductive substrate.

Abstract: Disclosed is an electrophotographic photoreceptor which gives a very low residual potential and scarcely accumulates the residual potential even by repeated use and which varies very slightly in a charging property and sensitivity and has a very excellent stability. The electrophotographic photoreceptor has a conductive support and a photoconductive layer provided on the conductive support. The photoconductive layer contains a charge-generating material, a charge-transporting material, a binder resin and a fatty acid ester compound represented by the following Formula (1): ##STR1## wherein R.sub.1, R.sub.2 and R.sub.3 each represent hydrogen or a saturated or unsaturated aliphatic hydrocarbon group which may have substituents, and n and m each represent an integer of 1 to 10.

Abstract: The present invention is directed to an electrophotographic photoreceptor which is smooth without orange peel, inhibits the rise of a residual potential and the drop of a charged potential, and is excellent in stability even when it is repeatedly used.The photoreceptor comprises a charge generation material, a charge transport material, a polyarylate having a polymerization degree of 10 to 5,000, a polycarbonate having a polymerization degree of 10 to 5,000, and a polydimethylsiloxane having a polymerization degree of 0 to 2,000.