Record receiver having plural interactive leaves or a colorless – Having a colorless color-former – developer therefor – or... – Method of use – kit – or combined with marking instrument or...
Patent
1995-03-28
1996-07-16
Hess, S. Hamilton
Record receiver having plural interactive leaves or a colorless
Having a colorless color-former, developer therefor, or...
Method of use, kit, or combined with marking instrument or...
430338, 430567, 430608, 430619, 503200, 503207, 503210, 503226, B41M 528
Patent
active
055366961
DESCRIPTION:
BRIEF SUMMARY
FIELD OF THE INVENTION
The present invention relates to a recording material suited for use in direct thermal imaging. More in particular the present invention relates to a recording material based on a heat induced reaction between a substantially light insensitive organic silver salt and a reducing agent.
BACKGROUND OF THE INVENTION
In thermography two approaches are known:
1. Direct thermal formation of a visible image pattern by imagewise heating of a recording material containing matter that by chemical or physical process changes colour or optical density.
2. Thermal dye transfer printing wherein a visible image pattern is formed by transfer of a coloured species from an imagewise heated donor element onto a receptor element.
Thermal dye transfer printing is a recording method wherein a dye-donor element is used that is provided with a dye layer wherefrom dyed portions of incorporated dye is transferred onto a contacting receiver element by the application of heat in a pattern normally controlled by electronic information signals.
The optical density of transparencies produced by the thermal transfer procedure is rather low and in most of the commercial systems--in spite of the use of donor elements specially designed for printing transparencies--only reaches 1 to 1.2 (as measured by a Macbeth Quantalog Densitometer Type TD 102). However, for many application fields a considerably higher transmission density is asked for. For instance in the medical diagnostical field a maximal transmission density of at least 2.5 is desired.
High optical densities can be obtained using a recording material comprising on a support a heat sensitive layer comprising a substantially light insensitive organic silver salt and a reducing agent. Such material can be image-wise heated using a thermal head causing a reaction between the reducing agent and the substantially light insensitive organic silver salt leading to the formation of metallic silver. To obtain a good thermosensitivity heating is carried by contacting the thermal head with the heat sensitive layer. The density level may be controlled by varying the amount of heat applied to the recording material. This is generally accomplished by controlling the number of heat pulses generated by the thermal head. An image having a grey scale is thus obtained.
Because of its high density the image is in principal suitable for use as a medical diagnostic image. However the following problems have been encounterred. Uneveness of density occurs with the number of images that have been printed and damaging of the heat sensitive layer occurs. These problems can be overcome by making use of a protective layer. Although this brings a substantial improvement so that the image may be suitable for some applications, the images show scratches that are prohibitive for the use of the image in medical diagnostics.
SUMMARY OF THE INVENTION
It is an object of the present invention to improve the quality of images obtained by direct thermal imaging of a recording material comprising on a support (i) a heat sensitive layer comprising a substantially light insensitive organic silver salt and (ii) a reducing agent being present in the heat sensitive layer or another layer on the same side of the support carrying the heat sensitive layer.
Further objects of the present invention will become clear from the description hereinafter.
According to the present invention there is provided a recording material comprising on a support (i) a heat sensitive layer comprising a substantially light insensitive organic silver salt, (ii) a protective layer containing a matting agent dispersed in a binder and (iii) a reducing agent being present in the heat sensitive layer and/or another layer on the same side of the support carrying the heat sensitive layer.
According to the present invention there is provided a method for making an image comprising image-wise heating by means of a thermal head a recording material as defined above said thermal head contacting the protective layer of said recording ma
REFERENCES:
patent: 3031329 (1962-04-01), Wingert
patent: 3107174 (1963-10-01), Wartman
patent: 4421560 (1983-12-01), Kito et al.
patent: 4904572 (1990-02-01), Dombrowski et al.
patent: 5198406 (1993-03-01), Mack et al.
patent: 5278127 (1994-01-01), Dombrowski et al.
Horsten Bartholomeus C.
Jansen Guy D. A.
Schuerwegen Ronald
Uyttendaele Carlo A.
AGFA-GEVAERT N.V.
Hess S. Hamilton
LandOfFree
Direct thermal imaging material does not yet have a rating. At this time, there are no reviews or comments for this patent.
If you have personal experience with Direct thermal imaging material, we encourage you to share that experience with our LandOfFree.com community. Your opinion is very important and Direct thermal imaging material will most certainly appreciate the feedback.
Profile ID: LFUS-PAI-O-1784197