Radiation imagery chemistry: process – composition – or product th – Luminescent imaging
Reexamination Certificate
2000-03-09
2002-03-12
Schilling, Richard L. (Department: 1752)
Radiation imagery chemistry: process, composition, or product th
Luminescent imaging
C430S236000, C430S220000, C430S363000, C355S032000, C355S037000, C355S070000
Reexamination Certificate
active
06355393
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to an image-forming method using a light-emitting element as a light source for exposure. More specifically, the present invention relates to a color image-forming method, in which images are obtained by digital exposure in accordance with image information using an organic light-emitting element, and carrying out development processing.
Further, the present invention relates to an organic light-emitting element for a light source for exposure. More specifically, the present invention relates to an organic light-emitting element for a light source for exposure for subjecting to digital exposure a silver halide light-sensitive material in accordance with image information.
Further, the present invention relates to an organic light-emitting element for use as a light source for exposure, which element is used in the color image-forming method.
BACKGROUND OF THE INVENTION
Heretofore, laser diodes (LD) and inorganic light-emitting emitting diodes (LED), known as light-emitting elements, have been utilized as light sources for exposure for writing on light-sensitive materials. However, the wavelengths of light to be emitted from LD or LED cannot be easily changed, and little latitude of choice of wavelength is left for blue-light-emitting elements in particular.
An organic light-emitting element is a self-light-emitting-type element that emits light according to the following mechanism. An organic compound layer, having a thickness of 1 &mgr;m or less, is held by being pinched between two electrodes, and a voltage is applied between the two electrodes. As a result, electrons are injected from one electrode (cathode), and holes are injected from another electrode (anode). Since the electrons and the holes are recombined in the organic compound layer, to excite the neighboring light-emitting material, light is emitted. In recent years, active research and development on organic light-emitting elements have been conducted.
Utilizing the advantage of being thin planar light-emitting elements, besides displays, conceivable uses of the organic light-emitting element include as a back light for an LCD, as a light source for illumination, as a light source for optical communication, as reading/writing heads for information files, and the like. The application of the organic light-emitting element to a light source for writing on a light-sensitive material is described in JP-A-7-22649 (“JP-A” means unexamined published Japanese patent application). In this official gazette, it has been proposed to expose generally commercialized photographic films, or films for instant cameras, by using an optical recording apparatus that has an optical writing unit, in a state of a dot array made up of organic light-emitting elements in a plurality of lines according to respective colors to be emitted. However, the light-emission spectra of elements are not specifically described in the official gazette. In a light-sensitive material, such as a silver halide color light-sensitive material having at least three spectral sensitivities in the visible light region, e.g., the three regions of red (R), green (G), and blue (B), the light-emission spectrum of a light source for exposure, particularly the light-emission spectrum of the light source in the central region (usually green (G)), is very important. This is because exposure using an ordinary organic light-emitting element having a broad half width leads to the problem that images having poor color reproduction are formed, due to the occurrence of color impurity (in the case of a negative light-sensitive material) and/or disappearing (or washing out) of color (in the case of a positive light-sensitive sensitive material). This phenomenon is likely to occur particularly in the exposed portion of the central region (generally green [G]); and particularly, if an ordinary green (G)-emitting organic light-emitting element, which has a broad half width, is used, part of the red (R) or blue (B) region is also exposed, and color impurity or disappearing of color as mentioned above is likely caused.
SUMMARY OF THE INVENTION
An object of the present invention is to solve the above-described problem. That is, an object of the present invention is to obtain color images exhibiting good color reproduction by exposing a light-sensitive material according to image information using a light-emitting element, in particular an organic light-emitting element, and carrying out development processing.
Another object of the present invention is to provide an organic light-emitting element for a light source for exposure in a green (G) region, with the said element exhibiting faithful color reproduction without causing color impurity or disappearing of color in the image to be obtained, when recording based on color image information is carried out in a light-sensitive material having at least three spectral sensitivities in the visible region.
Other and further objects, features, and advantages of the invention will appear more fully from the following description.
DETAILED DESCRIPTION OF THE INVENTION
The objects of the present invention have been attained by the following means.
(1) An image-forming method, which comprises:
subjecting a color light-sensitive material to exposure, by using, at least, a first light-emitting element whose peak wavelength of the light-emission spectrum is in a first wavelength region of 380 to 500 nm, a second light-emitting element whose peak wavelength of the light-emission spectrum is in a second wavelength region of 500 to 600 nm, and a third light-emitting element whose peak wavelength of the light-emission spectrum is in a third wavelength region of 600 to 740 nm, and
subjecting the exposed color light-sensitive material to development processing, wherein the color light-sensitive material has, at least, spectral sensitivities in the from first to third wavelength regions.
(2) The image-forming method as described in (1), wherein the peak wavelengths of the light-emission spectra of the first to third light-emitting elements are apart at least 50 nm from each other.
(3) The image-forming method as described in (1) or (2), wherein the half width of the light-emission spectrum of the second light-emitting element is 80 nm or less.
(4) The image-forming method as described in (3), wherein the half width of the light-emission spectrum of the second light-emitting element is 60 nm or less.
(5) The image-forming method as described in any one of (1) to (4), wherein the color light-sensitive material is a silver halide color light-sensitive material.
(6) The image-forming method as described in (5), wherein the silver halide color light-sensitive material is a diffusion transfer-type color light-sensitive material comprising:
a light-sensitive sheet, which comprises an image-receiving layer, a white reflecting layer, a light-shielding layer, and three light-sensitive silver halide emulsion layers that each are combined with a dye image-forming compound and each have a spectral sensitivity, at least, in the from first to third wavelength regions, provided on a transparent support,
a transparent cover sheet, which has at least a neutralizing layer and a neutralization-timing layer, provided on a transparent support, and
a light-shielding alkaline composition positioned in a developable way between the light-sensitive sheet and the transparent cover sheet.
(7) The image-forming method as described in any one of (1) to (6), wherein the exposure time per pixel is 1 to 10
−7
second.
(8) An organic light-emitting element for a light source for exposure, which has a transparent electrode and a back-side electrode on a substrate, and has at least one organic compound layer including a light-emitting layer, between the two electrodes, wherein the peak wavelength of the light-emission spectrum of the organic light-emitting element is 500 to 600 nm, and the half width of the light-emission spectrum of the organic light-emitting element is 80 nm or less.
(9) The organic light-emitting eleme
Araki Yasushi
Hirai Hiroyuki
Fuji Photo Film Co. , Ltd.
Schilling Richard L.
Sughrue & Mion, PLLC
LandOfFree
Image-forming method and organic light-emitting element for... does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Image-forming method and organic light-emitting element for..., we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Image-forming method and organic light-emitting element for... will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2873396