Radiation imagery chemistry: process – composition – or product th – Radiation sensitive product – Identified backing or protective layer containing
Reexamination Certificate
2001-07-18
2002-10-22
Schilling, Richard L. (Department: 1752)
Radiation imagery chemistry: process, composition, or product th
Radiation sensitive product
Identified backing or protective layer containing
C430S619000
Reexamination Certificate
active
06468726
ABSTRACT:
FIELD OF THE INVENTION
The present invention relates to a photothermographic image-recording material and more particularly to a photothermographic material.
BACKGROUND OF THE INVENTION
In recent years, it has been keenly desired in the art of film for medical diagnosis or photomechanical process film to reduce the amount of waste liquid to be disposed from the standpoint of environmental protection and reduction of space. Thus, a technique has been required concerning a photothermographic material as film for medical diagnosis or photomechanical process film which can be efficiently exposed to light by a laser image setter or laser imager to form a clear black image having a high resolution and sharpness. Such a photothermographic material requires no solution type processing chemicals and thus can provide customers with a simpler heat development system which is harmless to environment.
The art of general image-forming material, too, has the same requirements. In particular, an image for medical diagnosis is required to give a fine drawing and hence a high quality having excellent sharpness and graininess. Further, a blue black image is desired from the standpoint of ease of diagnosis. At present, various hard copy systems using pigment and dye such as ink jet printer and electrophotography are circulated as general imaging system. However, none of these systems are satisfactory as medical image outputting system.
On the other hand, heat imaging systems using an organic silver salt are disclosed in U.S. Pat. Nos. 3,152,904 and 3,457,075, D. Klosterboer, “Thermally Processed Silver Systems”, Imaging Processes and Materials, Neblette, 8th ed., compiled by J. Sturge, V. Walworth, A. Shepp, Chapter 9, page 279, 1989. In particular, a photothermographic material normally comprises a photosensitive layer having a catalytically active amount of a photocatalyst (e.g., silver halide), a reducing agent, a reducible silver salt (e.g., organic silver salt), and optionally a color toner for controlling the tone of silver dispersed in a binder matrix. A photothermographic material which has been imagewise exposed to light is heated to a high temperature (e.g., not lower than 80° C.) to undergo redox reaction of the reducible silver salt (which acts as an oxidizing agent) with the reducing agent, forming a black silver image. The redox reaction is accelerated by the catalytic action of latent image of silver halide produced by exposure. Thus, the black silver image is formed in the exposed area. This photothermographic material is disclosed in many references, including U.S. Pat. No. 2,910,377 and JP-B-43-4924 (The term “JP-B” as used herein means an “examined Japanese patent publication”).
In general, a silver halide photographic material comprises the foregoing photosensitive layer provided on a support. However, the adhesion between the support and the photosensitive layer is insufficient. Thus, it is practiced to provide a subbing layer on the support on the photosensitive layer side thereof for the purpose of improving the adhesion between the support and the photosensitive layer. Such a subbing layer is formed by applying a coating solution containing a styrene-butadiene copolymer or polyvinylidene chloride to the support. Similarly, JP-A-56-95959 (The term “JP-A” as used herein means an “unexamined published Japanese patent application”) proposes a technique involving the provision of a subbing layer containing polyesters on the support on the photosensitive layer side thereof for the purpose of improving the adhesion between the support and the photosensitive layer. Further, JP-A-11-84574 proposes a technique involving the provision of a subbing layer containing a polyester on the support of a photothermographic material on the photosensitive layer side thereof for the purpose of improving the adhesion between the support and the photosensitive layer. However, even when the subbing layer containing a specific aqueous polyester described in JP-A-56-95959 is applied to a photothermographic material, the resulting adhesion between the support and the subbing layer is insufficient. Further, the subbing layer disclosed in JP-A-11-84574, too, gives an insufficient adhesion between the support and the subbing layer, causing insufficiency in the shearing stability of the subbing layer coating solution upon the application of subbing layer and hence causing coating streaks or poor surface conditions.
SUMMARY OF THE INVENTION
An object of the present invention is to solve the foregoing problems with the prior art. In other words, an object of the invention is to solve is to provide a photothermographic image-recording material having a good adhesion between the subbing layer and the support or the image-forming layer.
Another object of the invention is to provide a subbing layer having a good adhesion to the support and image-forming layer, good surface conditions and a good mechanical stability. A further object of the invention is to provide a subbing layer having good surface conditions, i.e., no unevenness, and no streak due to good shearing stability of coating solution thereof for the purpose of obtaining a photothermographic image-recording material having good surface conditions and producibility.
The inventors made extensive studies of solution to the foregoing problems. As a result, it was found that an excellent photothermographic image-recording material having desired effects can be provided by providing at least one subbing layer comprising a polyester on at least one side of a support for photothermographic image-recording material, wherein the polyester is a polyester having a glass transition temperature of from 40° C. to 100° C. comprising an acid component and an alcohol component, the acid component comprises terephthalic acid and/or isophthalic acid in a total amount of from 40 to 90 mol % and isophthalic acid having a sulfonyloxy group represented by a specific structural formula in an amount of from 10 to 60 mol %, and the alcohol component comprises diethylene glycol in an amount of from 40 to 90 mol % and cyclohexane dimethanol in an amount of from 10 to 60 mol %. The present invention has thus been worked out.
The present invention provides a photothermographic image-recording material comprising a support, at least one subbing layer comprising a polyester provided on at least one side of the support and an image-forming layer provided on the subbing layer, wherein the polyester is a polyester having a glass transition temperature of from 40° C. to 100° C. comprising an acid component and an alcohol component, the acid component comprises at least one of terephthalic acid and isophthalic acid in a total amount of from 40 to 90 mol % based on the amount of the acid component and isophthalic acid having a sulfonyloxy group represented by the following formula (1) in an amount of from 10 to 60 mol % based on the amount of the acid component, and the alcohol component comprises diethylene glycol in an amount of from 40 to 90 mol % based on the amount of the alcohol component and cyclohexane dimethanol in an amount of from 10 to 60 mol % based on the amount of the alcohol component:
-(SO
3
)
n
M (1)
wherein M represents a hydrogen atom, alkaline or alkaline earth metal or quaternary ammonium residue, and n represents the same number as a valence number of M.
The image-forming layer preferably comprises a photosensitive silver halide, a photoinsensitive organic silver salt, a reducing agent for silver ion and a binder.
DETAILED DESCRIPTION OF THE INVENTION
Methods and embodiments of implication of the present invention will be described in detail hereinafter. The term “from (x) to (y)” as used herein is meant to indicate that x is the lower limit of the range and y is the upper limit of the range, and the lower limit and the upper limit are fallen within the range. That is, the term means “from (x) to (y) both inclusive”.
The photothermographic image-recording material according to the invention comprises a support, at least one subbing layer comprising a po
Fujikura Sadao
Haraoka Hiroshi
LandOfFree
Photothermographic image-recording material with polyester sub does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Photothermographic image-recording material with polyester sub, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Photothermographic image-recording material with polyester sub will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-2956647