A light-sensitive heat-sensitive recording material is disclosed, which contains microcapsules resulting from a solution containing at least one component capable of undergoing color development or achromatization as a core material of the microcapsules and a volatile solvent which has a water solubility of 10% by volume or less and has a low boiling point such that it volatilizes during a process for preparing said light-sensitive heat-sensitive recording material leaving substantially no trace of the solvent in the resulting recording material. As the microcapsules, ones having a mean particle size of 2 .mu.m or less are preferred, and ones prepared using a modified gelatin as a protective colloid are also preferred. Further, as the support of the light-sensitive heat-sensitive recording material, a polyester support filled with a white pigment can preferably be used.

FIELD OF THE INVENTION 
This invention relates to a light-sensitive heat-sensitive recording 
material which can be used for a color or black-and-white proof, a slide, 
an overhead projector, a secondary drawing, a copying machine, facsimile 
and the like. 
BACKGROUND OF THE INVENTION 
Prior art recording materials are described below using a color proof as 
exemplary since almost the same description can be made with regard to 
other materials in the field except for their uses. 
An overlay system is a typical example of a color proof system. In this 
system, different monochrome films are laminated to produce a multi-color 
image which has a poor image quality because it must be seen through 
films. 
A surprint system is known as another type of color proof system in which a 
multi-color image is provided on a single sheet. In this system, a 
multicolor image is obtained by laminating images of different colors one 
by one on a single support. For example, Chromalin (Du Pont Co.), Match 
Print (3M), Color Art (Fuji Photo Film Co., Ltd.) and the like are known 
examples of this type of color proof system, but each of them requires 
four light-sensitive films for corresponding colors. This results in the 
generation of waste materials. 
In addition, a color paper system is known as a process for the formation 
of a color image on a single light-sensitive sheet. In this system, a film 
original is superposed closely on a sheet of color paper, exposure is 
effected using different color filters and then a color image is obtained 
by wet development. Fine Checker (Fuji Photo Film Co., Ltd.), Consensus 
(Konica Corp.) and the like are known as examples of this type of system. 
However, since the color paper is sensitive to visible light, this system 
requires a darkroom or an exposure apparatus equipped with a darkroom, as 
well as the necessity to maintain a developing solution. 
As a consequence, these prior art systems nave certain disadvantages such 
as the necessity of using a plurality of sheets, the generation of waste 
materials including transfer sheets and toners, difficulty in handing in 
daylight, necessity to establishing a developing system using developing 
solution and the like. 
A process has been proposed solving these prior art problems. According to 
this process, an absolute dry system which does not generate any waste 
material is achieved by using: (a) a light-sensitive heat-sensitive 
recording material of the type in which a latent image is formed upon 
exposure in a photo-hardenable composition and, when heated, a component 
capable of undergoing color development or achromatization moves inside 
the light-sensitive heat-sensitive material in response to the latent 
image to form an image; and (b) a process for the preparation of color 
images which compresses exposing the light-sensitive heat-sensitive 
recording material through an image original, forming a latent image on 
the exposed portion by light-sensitive hardening and thereafter forming a 
visible image by heating the recording material to disperse the component 
capable of undergoing color development or achromatization remaining the 
un-hardened portion. 
There are several illustrative examples of this type of recording material, 
and they are not only applicable to a recording system for a 
black-and-white image but also especially effective when used as a color 
recording material. 
An illustrative example of this type of recording material is disclosed in 
JP-A 52-89915 (the term "JP-A" as used herein means an "unexamined 
published Japanese patent application") in which two components of a two 
component type heat-sensitive recording material, for example, an electron 
accepting compound and an electron donating colorless dye, are separately 
arranged inside and outside or on both sides of microcapsules containing a 
photo-hardenable composition. In this recording material, however, the 
non-image portions are slightly colored thus showing a tendency for the 
contrast of the resulting image to be lowered, because development of 
color on the hardened portions cannot be prevented to a sufficient level 
even when the photo-hardenable composition in the microcapsules is 
hardened sufficiently. 
A more preferred recording material which does not develop color in the 
non-image portions is disclosed, for instance, in JP-A-61-123838 in which 
a layer containing a photopolymerizable composition comprising an acid 
group-containing vinyl monomer and a photopolymerization initiator, an 
insulating layer and a layer comprising an electron donating colorless dye 
are laminated. In this type of recording material, thermal dispersion of 
the acid group becomes negligible in the non-image portion, i.e., in the 
hardened portion of the photopolymerizable layer. Although a color is not 
developed in the non-image portion because of such an effect, this 
recording material has the disadvantage of a somewhat low color density. 
An example of a process for the formation of negative images in a similar 
manner is disclosed, for instance, in JP-A-60-119552 which comprises using 
a recording material in which a photopolymerizable composition comprising 
a monomer or a prepolymer capable of bleaching a dye and the dye to be 
bleached by the monomer or prepolymer are separately located. This 
recording material, however, has the same disadvantages as those of the 
above-described recording materials. 
A recording material disclosed in Japanese Patent Application No. 1-224930 
(corresponding to U.S. patent application Ser. No. 07/567,040, which is 
now U.S. Pat. No. 5,091,280) may be regarded as a most preferred material 
in which these problems concerning coloring of a non-image portion and low 
color density were resolved. This recording material is a two component 
type heat-sensitive recording material in which one of the two components 
is included in microcapsules and the other component is arranged outside 
the microcapsules as a hardenable compound of a photo-hardenable 
composition or together with the photo-hardenable composition. 
Also, a recording material for negative image formation developed by 
employing a similar idea is disclosed in Japanese Patent Application No. 
2-19710 (corresponding to U.S. patent application Ser. No. 07/567,040, now 
U.S. Pat. No. 5,091,280) in which a photopolymerizable composition 
comprising an electron accepting compound, a polymerizable vinyl monomer 
and a photopolymerization initiator is arranged outside of microcapsules, 
and a Layer containing the photopolymerizable composition and the 
microcapsules, which include an electron donating colorless dye, is coated 
on a support. 
When color recording is attempted using one of these prior art recording 
materials, a recording material which comprises a plurality of 
light-sensitive layers each having different sensitive wave length and hue 
may basically be selected. More preferable multi-color recording materials 
are disclosed, for instance, in Japanese Patent Application Nos. 1-224930 
and 2-19710, such as a multi-color recording medium which comprises a 
plurality of light-sensitive layers each of them sensitive to different 
wave length of light and capable of developing different color wherein the 
color recording medium comprises a layer structure of at least two 
light-sensitive layers laminated on a support, the layer structure 
comprising a first light-sensitive layer which is sensitive to light of a 
central wave length of .lambda.1, an intermediate layer which absorbs 
light of a central wave length of .lambda.1, a second light-sensitive 
layer which is sensitive to light of a central wave length of .lambda.2 
and develops a different color from the first light-sensitive layer . . . 
, an intermediate layer which absorbs a light of central wave length of 
.lambda.i-1 and an i-th light-sensitive layer which is sensitive to a 
light of central wave length of .lambda.i and develops a different color 
from the first, second, . . . , and (i-1)-th light-sensitive layers, in 
that order starting from the side of exposure to light toward the support 
side of the recording material, the central wave lengths being in the 
order of .lambda.1&lt;.lambda.2&lt;. . .&lt;.lambda.i where i is an integer of 2 or 
more. 
These prior art light-sensitive heat-sensitive recording materials, 
however, have the disadvantage of poor resolution due, probably, to the 
restriction of the size of picture element by the limited particle size of 
microcapsules to be used, as well as another problem of poor image quality 
due to light scattering. These problems are important problems to be 
solved especially when high resolution is required such as in the case of 
proofs and slides. 
With such light-sensitive heat-sensitive recording materials, heat 
development is carried out at a temperature of from 100.degree. to 
200.degree. C. after light-sensitive recording. During the heat 
development process, a solvent present in microcapsules evaporates and 
condenses on the inner wall of a heat developing machine which 
subsequently causes not only staining of the recording material and the 
developing machine but also the generation of an offensive odor when 
volatilized into the air around the developing machine. In an extreme 
condition, the volatilized solvent will even damage the health of persons 
around the machine. 
In addition to these problems, these prior art light-sensitive 
heat-sensitive recording materials have a tendency to be cloudy or hazy, 
probably, due to the existence of particles such as microcapsules and 
emulsified components in their coat layers. Since this type of haze 
decreases the visibility of images, application of these sensitive 
materials especially to overhead projection (OHP), slides and the like, 
which require transmission images, results in a dark and unclear total 
image due to poor transmission of light due to the haze. 
These disadvantages of the prior art materials are fatal especially with a 
multilayer light-sensitive heat-sensitive color recording material, 
because the disadvantages in each layer of the recording material are 
compounded. 
As a result, resolution of these problems has been desired in the area 
especially of color recording materials, not to mention monochrome 
recording materials. 
On the other hand, although these recording materials can be used in many 
applications, they are generally applied to the formation of reflection 
images in which images are formed on a white paper support. Since these 
prior art light-sensitive heat-sensitive recording materials form images 
by--recording with light, formation of high resolution images could 
expected. However, a light-sensitive heat-sensitive recording material in 
which the above-described light-sensitive heat-sensitive layers are formed 
on a paper support as a typical white support produces uneven images with 
poor resolution, thus requiring further improvements. 
As a means to resolve such unevenness and poor resolution, use of a support 
laminated with a polyolefin such as polyethylene or polypropylene has been 
proposed. However, since light-sensitive heat-sensitive recording 
materials to which the present invention is related require a heat 
development step, for example, at 120.degree. C. for 5 seconds, the 
laminated polyethylene or polypropylene cannot tolerate the heat 
development temperature and therefore its shape begins to change thus 
resulting in wavy or distorted recording layers. 
Another measure to resolve such poor resolution and unevenness involved use 
of a synthetic paper which is well known in this field. Thus, however, 
still results in deformation at the time of heat development to such a 
degree that the recording material cannot be used. 
In addition, there is still another problem to be solved in use of a paper 
support or a laminated paper, that is, formation of fog which occurs when 
heat development is carried out an extended period of time after the 
formation of the latent image by exposure. 
On the other hand, although these recording materials can be used in many 
applications, they are generally used in the form of a multi-layer 
structure involving an overcoat layer, an undercoat layer, an intermediate 
layer and the like. In this case, layers should be coated onto a support 
in a multi-layer structure. However, if each of the layers is separately 
coated one after another, there is disadvantageous in terms of cost and 
yield. 
In the field of silver halide photographic materials, all of coating 
solutions for layers to be provided are formulated in a gelatin system and 
they are simultaneously coated onto a support by multi-coating technique 
utilizing a low-temperature setting property of gelatin. Accordingly, if 
this technique is employed, simultaneous multi-layer-coating can be 
conducted in the preparation of the above-mentioned recording materials. 
However, if gelatin itself is used as a protective colloid for emulsifying 
and dispersing a component capable of undergoing color development or 
achromatization to be microencapsulated, a reactant existing as a capsule 
wall-forming material (e.g., an isocyanate) rapidly reacts with gelatin at 
the beginning of the emulsification, whereby flocculation of components 
occurs and microencapsulation is hardly conducted. 
Accordingly, there have been required to attain a microencapsulation 
technique using gelatin protective colloid. 
SUMMARY OF THE INVENTION 
In view of the above, it therefore an object of the present invention is to 
provide a light-sensitive heat-sensitive black-and-white or color 
recording material of dry treatment type which neither generates waste 
materials nor requires a developing solution and the like and which forms 
a clear image with high resolution and less light scattering. 
Another object of the present invention is to provide a light-sensitive 
heat-sensitive black-and-white or color recording material of the dry 
treatment type which neither generates waste materials nor requires a 
developing solution and the like in which environmental pollution is taken 
into consideration. Also provided are a light-sensitive heat-sensitive 
recording material which can be used to form an image with low haze and 
high visibility and a light-sensitive heat-sensitive recording material 
that can be applied to projection type purposes such as OHP's, slides and 
the like. 
Still another object of the present invention is to provide a 
light-sensitive heat-sensitive black-and-white or color recording material 
of the dry treatment type which neither generates waste materials nor 
requires a developing solution and the like and which provides a high 
resolution image. Also provided is a light-sensitive heat-sensitive 
recording material which provides a clear image with no unevenness, a 
recording material which does not deform at the time of heat development 
and a light-sensitive heat-sensitive recording material which can provide 
a clear image with no fog formation even when a prolonged period of time 
exists between exposure and heat development. 
A still further object of the present invention is to provide a process for 
preparing microcapsules using a gelatin protective colloid which does not 
cause aggregation or troubles such as unevenness and repellence of coating 
solution. Also provided are a light-sensitive heat-sensitive 
black-and-white or color recording material of the dry treatment type 
which neither generates waste materials nor requires a developing solution 
and the like and which employs microcapsules prepared by the process. 
The objects of the present invention is accomplished by (1) a 
light-sensitive heat-sensitive recording material of the type in which a 
latent image is formed upon exposure in a photo-hardenable composition 
and, when heated, a component capable of undergoing color development or 
achromatization moves inside the light-sensitive heat-sensitive recording 
material in response to the latent image to form an image, wherein the 
light-sensitive heat-sensitive recording material comprises a support 
having on at least one side thereof a light-sensitive heat-sensitive layer 
comprising microcapsules containing at least one component capable of 
undergoing color development or achromatization, the microcapsules 
resulting from a solution containing at least one component capable of 
undergoing color development or achromatization as a core material of the 
microcapsules and a volatile solvent which has a water solubility of 10% 
by volume or less and has such a low boiling point that it volatilizes 
during the process for preparing the light-sensitive heat-sensitive 
recording material leaving substantially no trace of the solvent in the 
resulting recording material, or (2) a light-sensitive heat-sensitive 
recording material of the type in which a latent image is formed upon 
exposure in a photo-hardenable composition contained outside of the 
microcapsules and, when heated, an electron accepting compound moves 
inside the light-sensitive heat-sensitive recording material in response 
to the latent image to form an image by developing color of an electron 
donating colorless dye present in the microcapsules, wherein the 
light-sensitive heat-sensitive recording material comprises a support 
having on at least one side thereof a light-sensitive heat-sensitive layer 
comprising microcapsules resulting from a solution containing at least one 
electron donating colorless dye as a core material of the microcapsules 
and a volatile solvent which has a water solubility of 10% by volume or 
less and has such a low boiling point that it volatilizes during the 
process for preparing the light-sensitive heat-sensitive recording 
material leaving substantially no trace of the solvent in the resulting 
recording material. 
The objects of the present invention are also accomplished by the 
above-mentioned light-sensitive heat-sensitive recording materials in 
which the microcapsules have a mean particle size of 2 .mu.m or less. 
The objects of the present invention are further accomplished by the 
above-mentioned light-sensitive heat-sensitive recording material in which 
the support is a polyester support filled with a white pigment. 
The objects of the present invention are furthermore accomplished by the 
above-mentioned light-sensitive heat-sensitive recording material in which 
a support is provided with a flatting surface layer. 
The objects of the present invention are still furthermore accomplished by 
a method for preparing microcapsules using a modified gelatin as a 
protective colloid in the emulsification and dispersion step and by the 
light-sensitive heat-sensitive recording material comprising microcapsules 
prepared using a modified gelatin as a protective colloid in the 
emulsification and dispersion step. 
DETAILED DESCRIPTION OF THE INVENTION 
By the use of the light-sensitive heat-sensitive recording material of the 
present invention, haze can be reduced to such a level that the material 
can be applied to projection use such as OHP's, slides and the like. In 
other words, prior art problems with respect to solvent vaporization and 
haze formation are simultaneously resolved by the use of the recording 
material of the present invention. 
An illustrative example in relation to the recording material of the 
present invention is disclosed, for instance, in Japanese Patent 
Application No. 1-224930 (corresponding to U.S. patent application Ser. 
No. 07/567,040, now U.S. Pat. No. 5,091,280) in which a layer is laminated 
on a support wherein the layer comprises microcapsules containing an 
electron donating colorless dye and a light-hardenable composition 
arranged outside of the microcapsules, the light-hardenable composition 
comprising a compound having an electron accepting moiety and a 
polymerizable vinyl monomer moiety both in the molecule thereof and a 
photopolymerization initiator. When this recording material is exposed to 
light, the exposed portion of the light-hardenable composition arranged 
outside of the microcapsules is polymerized to form a latent image and, 
when the thus exposed material is heated, the compound having an electron 
accepting moiety moves inside the light-sensitive heat-sensitive recording 
material in response to the latent image to form a positive image with 
excellent contrast by developing the color of an electron donating 
colorless dye present in the microcapsules. 
In addition, a negative image can be formed making use of a similar process 
using the recording material of the present invention. An illustrative 
example of such a process is disclosed, for instance, in Japanese Patent 
Application No. 2-19710 (corresponding to U.S. patent application Ser. No. 
07/567,040, now U.S. Pat. No. 5,091,280) in which a recording material is 
prepared by coating a support with a layer which comprises microcapsules 
containing an electron donating colorless dye and a light-hardenable 
composition arranged outside of the microcapsules, the light-hardenable 
composition comprising an electron accepting compound, a polymerizable 
vinyl monomer and a photopolymerization initiator. When this recording 
material is exposed to light, the exposed portion of the light-hardenable 
composition arranged outside of the microcapsules is polymerized to form a 
latent image and, when the thus exposed material is heated, an electron 
accepting compound in the polymerization portion moves inside the 
light-sensitive heat-sensitive material in response to the latent image to 
form a negative image with excellent contrast by developing the color of 
an electron donating colorless dye present in the microcapsules. 
As has been described above, various processes can be employed in the 
production of the recording material of the present invention, that is, "a 
light-sensitive heat-sensitive recording material of the type in which a 
latent image is formed upon exposure in a photo-hardenable composition 
and, when heated, a component capable of undergoing color development or 
achromatization moves inside the light-sensitive heat-sensitive material 
in response to the latent image to form an image". 
The light-sensitive heat-sensitive layer used in the recording material of 
the present invention is not strictly limited to the above described 
construction and various constructions, may arise depending on each 
object. 
The recording material for use in the present invention may be either a 
monochrome, the so-called B/W, recording material or a multicolor 
recording material. In the case of a multicolor recording material, it 
may, for example, comprise multilayers in which each layer comprises 
microcapsules containing an electron donating colorless dye which develops 
a different color from the other layers and a photo-hardenable composition 
that responds to different wave lengths of light. Examples of such 
constructions include: a construction in which a first light-sensitive 
heat-sensitive layer comprising microcapsules containing a cyan-developing 
electron donating colorless dye and a photo-hardenable composition which 
responds to light of a central wave length .lambda.1 is coated on a 
support, a second light-sensitive heat-sensitive layer comprising 
microcapsules containing a magenta-developing electron donating colorless 
dye and a photo-hardenable composition which responds to light of a 
central wave length .lambda.2 is coated on the first light-sensitive 
heat-sensitive layer and a third light-sensitive heat-sensitive layer 
comprising microcapsules containing a yellow-developing electron donating 
colorless dye and a photo-hardenable composition which responds to light 
of a central wave length .lambda.3 is further coated on the second 
light-sensitive heat-sensitive layer; a construction in which intermediate 
layers are interposed between these light-sensitive heat-sensitive layers; 
and a construction in which a UV-absorbing agent is present in the 
intermediate layers. 
In the case of a multicolor recording material, the just described 
construction in which a UV-absorbing agent is present in intermediate 
layers is most preferable, such as a construction in which a first 
light-sensitive heat-sensitive layer comprising microcapsules containing a 
cyan-developing electron donating colorless dye and a photo-hardenable 
composition which responds to light of a central wave length .lambda.1 is 
coated on a support, a first intermediate layer containing a UV-absorbing 
agent which absorbs light of shorter range of wave length than .lambda.1 
is coated on the first light-sensitive heat-sensitive layer, a second 
light-sensitive heat-sensitive layer comprising microcapsules containing a 
magenta-developing electron donating colorless dye and a photo-hardenable 
composition which responds to light of a central wave length .lambda.2 is 
coated on the first intermediate layer, a second intermediate layer 
containing a UV-absorbing agent which absorbs shorter range of light of 
wave length than .lambda.2 is coated on the second light-sensitive 
heat-sensitive layer, a third light-sensitive heat-sensitive layer 
comprising of microcapsules containing a yellow-developing electron 
donating colorless dye and a photo-hardenable composition which responds 
to light of a central wave length .lambda.3 is coated on the second 
intermediate layer, and then a protective layer is coated on the third 
light-sensitive heat-sensitive layer. Preferably, all of the central 
wavelengths .lambda.1, .lambda.2 and .lambda.3 of the light-sensitive 
heat-sensitive recording material of the present invention are 320 nm or 
more, both of .lambda.1 and .lambda.2 are less than 400 nm and .lambda.3 
is 400 nm or more. 
One particular embodiment of the present invention is a light-sensitive 
heat-sensitive recording material which comprises a layer structure of at 
least two light-sensitive heat-sensitive layers laminated on a support, 
the layer structure comprising a first light-sensitive heat-sensitive 
layer which is sensitive to light of a central wave length of .lambda.1, 
an intermediate layer which absorbs light of a central wave length of 
.lambda.1, a second light-sensitive heat-sensitive layer which is 
sensitive to light of a central wave length of .lambda.2 and develops a 
different color from the first light-sensitive heat-sensitive layer, an 
intermediate layer which absorbs light of a central wave length of 
.lambda.i-1 and an i-th light-sensitive heat-sensitive layer which is 
sensitive to light of a central wave length of .lambda.i and develops a 
different color from the first, second and (i-1)-th light-sensitive 
heat-sensitive layers, in that order from the side of exposure light 
toward the support side of the recording material, the central wave 
lengths being in the order of .lambda.1&lt;.lambda.2&lt;. . .&lt;i where i is an 
integer of 2 or more. Where i is 3, all of the central wave lengths 
.lambda.1, .lambda.2 and .lambda.3 of the light-sensitive heat-sensitive 
layers can be 320 nm or more, wherein both .lambda.1 and .lambda.2 are 
less than 400 nm and .lambda.3 is 400 nm or more. 
An electron accepting and polymerizable vinyl monomer used mainly in a 
positive type recording material of the present invention may be selected 
from those compounds in which an electron accepting group and a vinyl 
group are present in the same molecule. Illustrative examples of such 
compounds include, for instance, a methacryloxyethyl ester of benzoic acid 
having a hydroxy group as disclosed in JP-A-63-173682 or an acryloxyethyl 
ester which can be synthesized using same method disclosed in 
JP-A-63-173682, an ester of benzoic acid having a hydroxy group and 
hydroxymethylstyrene as disclosed in JP-A-59-83693, JP-A-60-141587 and 
JP-A-62-99190, a hydroxystyrene as disclosed in European Patent 29323, an 
N-vinylimidazole complex of a zinc halide as disclosed in JP-A-62-167077 
and JP-A-62-16708, a developer monomer as disclosed in JP-A-63-317558, and 
various other compounds synthesized based on these prior art compounds. 
Illustrative examples of these compounds include 
styrenesulfonylaminosalicylic acid, vinylbenzyloxyphthalic acid, zinc 
.beta.-methacryloxyethoxysalicylate, zinc .beta.-acryloxyethoxysalicylate, 
vinyloxyethyloxybenzoate, .beta.-methacryloxyethylorsellinate, 
.beta.-acryloxyethylorsellinate, .beta.-methacryloxyethoxyphenol, 
.beta.-acryloxyethoxyphenol, .beta.-methacryloxyethyl-.beta.resolcinate, 
.beta.-acryloxyethyl-.beta.-resolcinate, hydroxystyrenesulfonic 
acid-N-ethylamide, .beta.-methacryloxypropyl-p-hydroxybenzoate, 
.beta.-acryloxypropyl-p-hydroxybenzoate, methacryloxymethylphenol, 
acryloxymethylphenol, methacrylamidopropanesulfonate, 
acrylamidopropanesulfonate, .beta.-methacryloxyethoxydihydroxybenzene, 
.beta.-acryloxyethoxydihydroxybenzene, 
.gamma.-styrenesulfonyloxy-.beta.-methacryloxypropanecarbonate, 
.gamma.-acryloxypropyl-.alpha.-hydroxyethyloxysalicylate, 
.beta.-hydroxyethoxycarbonylphenol, 
.beta.-methacryloxyethyl-p-hydroxycinnamate, 
.beta.-acryloxyethyl-p-hydroxycinnamate, 3,5-distyrenesulfonic acid 
amidophenol, methacryloxyethoxyphthalic acid, acryloxyethoxyphthalic acid, 
methacrylic acid, acrylic acid, methacryloxyethoxyhydroxynaphthoic acid, 
acryloxyethoxyhydroxynaphthoic acid, 3-.beta.-hydroxyethoxyphenol, 
.beta.-methacryloxyethyl-p-hydroxybenzoate, 
.beta.-acryloxyethyl-p-hydroxybenzoate, 
.beta.'-methacryloxyethyl-.beta.resorcinate, 
.beta.-methacryloxyethyloxycarbonylhydroxybenzoic acid, 
.beta.-acryloxyethyloxycarbonylhydroxybenzoic acid, 
N,N'-di-.beta.-methacryloxyethylaminosalicylic acid, 
N,N'-di-.beta.-acryloxyethylaminosalicylic acid, 
N,N'-di-.beta.-methacryloxyethylaminosulfonylsalicylic acid, 
N,N'-di-.beta.-acryloxyethylaminosulfonylsalicylic acid, and metal salts 
thereof, preferably zinc salts. 
Photopolymerization initiators suitable for use in the recording material 
of the present invention may be selected from the compounds which can 
initiate photopolymerization of the aforementioned vinyl monomers. These 
compounds may be used alone or as a mixture of two or more thereof. 
Illustrative examples of preferred photo-polymerization initiators include: 
aromatic ketones such as benzophenone, 
4,4'-bis(dimethylamino)benzophenone, 4-methoxy-4'-dimethylaminobenzophenon 
e, 4,4'-dimethoxybenzophenone, 4-dimethylaminobenzophenone, 
4-dimethylaminoacetophenone, benzyl, anthraquinone, 
2-tert-butylanthraquinone, 2-methylanthraquinone, xanthone, thioxanthone, 
2-chlorothioxanthone, 2,4-diethylthioxanthone, fluorenone, acridone and 
the like; benzoin and benzoin ethers such as benzoin methyl ether, benzoin 
ethyl ether, benzoin isopropyl ether, benzoin phenyl ether and the like; 
2,4,5-triarylimidazol dimers such as 
2-(o-chlorophenyl)-4,5-diphenylimidazol dimer, 
2-(o-chlorophenyl)-4,5-di(m-methoxyphenyl)imidazol dimer, 
2-(o-fluorophenyl)-4,5-diphenylimidazol dimer, 
2-(o-methoxyphenyl)-4,5-diphenylimidazol dimer, 
2-(p-methoxyphenyl)-4,5-diphenylimidazol dimer and the like; 
polyhalogenides such as carbon tetrabromide, phenyltribromomethyl sulfone, 
phenyltrichloromethyl ketone and the like, and compounds disclosed in the 
specifications of JP-A-53-133428, JP-B-57-1819, JP-B-57-6096 and U.S. Pat. 
3,615,455; and S-triazine derivatives having trihalogen-substituted methyl 
groups disclosed in JP-A-58-29803 such as 
2,4,6-tris(trichloromethyl)-S-triazine,2-methoxy-4,6-bis(trichloromethyl)- 
S-triazine, 2-amino-4,6-bis(trichloromethyl)-S-triazine, 
2-(p-methoxystyryl)-4,6-bis(trichloromethyl)-S-triazine and the like. Also 
included are organic peroxides disclosed, for example, in JP-A-59-189340 
such as methyl ethyl ketone peroxide, cyclohexanone peroxide, 
3,3,5-trimethylcyclohexanone peroxide, benzoyl peroxide, 
di-tert-butyl-di-peroxyisophthalate, 
2,5-dimethyl-2,5-di(benzoylperoxy)hexane, tert-butylperoxybenzoate, 
.alpha.,.alpha.'-bis(tert-peroxybutylisopropyl)benzene, dicumyl peroxide, 
3,3',4,4'-tetra-(tert-butylperoxycarbonyl)benzophenone and the like. Also 
included are azinium compounds disclosed, for example, in U.S. Pat. No. 
4,743,530, and organic boron compounds disclosed, for example, in European 
Patent 0,223,587 such as tetramethylammonium salts of 
triphenylbutylborate, tetrabutylammonium salts of triphenylbutylborate, 
tetramethylammonium salts of tri(p-methoxyphenyl)butylborate and the like. 
Other well known prior art photo polymerization initiators such as 
diaryliodonium salts and iron-allene complexes are also useful for the 
purposes of the present invention. (The term "JP-B" as used herein means 
an "examined Japanese patent publication".) 
In addition, a combination of two or more compounds as a 
photopolymerization initiator system can be employed in the present 
invention. Examples of such a system include a combination of 
2,4,5-triarylimidazole dimer and mercaptobenzoxazole or the like, a 
combination of 4,4'-bis(dimethylamino)benzophenone and benzophenone or 
benzoin methyl ether as disclosed in U.S. Pat. No. 3,427,161, a 
combination of benzoyl-N-methylnaphthothiazoline and 
2,4-bis(trichloromethyl)-6-(4'-methoxyphenyl)triazol as disclosed in U.S. 
Pat. No. 4,239,850, a combination of dialkylaminobenzoic ester and 
dimethylthioxanthone as disclosed in JP-A-57-23602 and a triple 
combination of 4,4'-bis(dimethylamino)benzophenone, benzophenone and a 
polyhalogenated methyl compound as disclosed in JP-A-59-78339. A 
combination of 4,4'-bis(diethylamino)benzophenone and benzophenone, a 
combination of 2,4-diethylthioxanthone and 4-dimethylaminoethylbenzoate 
and a combination of 4,4'-bis(diethylamino)benzophenone and 
2,4,5-triarylimidazole dimer are purticularly preferable. 
Most preferred compounds of these photo-polymerization initiators are 
benzoin ethers, S-triazine derivatives having a trihalo-substituted methyl 
group, organic peroxides, azinium salt compounds and organic boron 
compounds. 
The photopolymerization initiator is preferably used in an amount of from 
0.01 to 20% by weight on the basis of the total weight of the 
photopolymerizable composition, more preferably from 0.2 to 15% by weight, 
most preferably from 5 to 10% by weight. Use of an amount less than 0.01% 
by weight causes insufficient sensitivity and use of an amount more than 
20% by weight provide no proportionally increased sensitivity. 
In addition to the polymerizable vinyl monomer and photopolymerization 
initiator, a spectral sensitization dye is also used in the 
photo-hardenable composition of the recording material of the present 
invention for the purpose of controlling the sensitive wave length. Such a 
spectral sensitization dye may be selected from various compounds known in 
art, by consulting, for example, the aforementioned patents cited in 
relation to photopolymerization initiators, Research Disclosure, vol. 200, 
Item 20036 (December, 1980) and Zokanzai (Sensitizer) (pages 160 to 163; 
edited by K. Tokumaru and S. Ohgawara, published by Kodansha in 1987; in 
Japanese). 
Illustrative examples of spectral sensitization dyes include, for example, 
3-keto-coumarin compounds disclosed in JP-A-58-15503, thiopyrylium salts 
disclosed JP-A-58-40302, naphthothiazole merocyanine compounds disclosed 
in JP-B-59-28328 and JP-B-60-53300 and merocyanine compounds disclosed in 
JP-B-61-9621, JP-B-62-3842, JP-A-59-89303 and JP-A-60-60104. By the use of 
these spectral sensitization dyes, the spectral sensitivity of a 
photopolymerization initiator can be extended to the visible wave length. 
Though trihalomethyl-S-triazine compounds are exemplified as 
photopolymerization initiators in the foregoing prior arts, these spectral 
sensitization dyes can also be used in combination with other 
photopolymerization initiators. Illustrative examples of spectral 
sensitization dyes include: keto dyes such as a coumarin dye (including 
ketocoumarin or sulfonocoumarin), a merostyryl dye, an oxonol dye and a 
hemioxonol dye; non-keto dyes such as a non-keto polymethine dye, an 
anthracene dye, a rhodamine dye, an acridine dye, an aniline dye and an 
azo dye; non-ketopolymethine dyes such as cyanine, hemicyanine and a 
styryl dye; and other dyes. 
In addition, the photopolymerizable composition of the present invention 
may be used in combination with polymerization enhancing auxiliary agents 
such as reducing agents like an oxygen scavenger and chain transfer agents 
of an active hydrogen donor type, as well as other compounds which enhance 
the polymerization by chain transfer. Useful oxygen scavengers include 
phosphines, phosphonates, phosphites and stannous salts, as well as other 
compounds which can be oxidized easily by oxygen such as N-phenylglycine, 
trimethylbarbiturate, N,N-dimethyl-2,6-diisopropylaniline, 
N,N,N-2,4,6-pentamethylaniline and the like. Also useful polymerization 
enhancers are thiols, thioketones, trihalomethyl compounds, lophine dimer 
compounds, iodonium salts, sulfonium salts, azinium salts, organic 
peroxides and the like. 
An electron accepting compound is preferably used in a negative type 
recording material of the present invention. Also, when required, such an 
electron accepting compound may be added to the photo-hardenable 
composition in a positive type recording material in order to increase the 
color density. Such electron accepting compounds include phenol 
derivatives, derivatives of salicylic acid, metal salts of aromatic 
carboxylic acids, acid clay, bentonite, novolak resins, metal-treated 
novolak resins, metal complexes and the like. Illustrative examples of 
these compounds are disclosed, for instance, in JP-B-40-9309, 
JP-B-45-14039, JP-A-52-140483, JP-A-48-51510, JP-A-57-210886, 
JP-A-58-87089, JP-A-59-11286, JP-A-60-176795 and JP-A-61-95988. 
Illustrative examples of such phenolic compounds include 
2,2'-bis(4-hydroxyphenyl)propane, 4-t-butylphenol, 4-phenylphenol, 
4-hydroxydiphenoxide, 1,1'-bis(3-chloro-4-hydroxyphenyl)cyclohexane, 
1,1'-bis(4-hydroxyphenyl)cyclohexane,1,1'-bis(3-chloro-4-hydroxyphenyl)-2- 
ethylbutane, 4,4'-sec-isooctylidene diphenol, 4,4'-sec-butylidene diphenol, 
4-tert-octyl phenol, 4-p-methylphenyl phenol, 4,4'-methylcyclohexylidene 
phenol, 4,4'-isopentylidene phenol, benzyl p-hydroxybenzoate and the like. 
Illustrative examples of the salicylic acid derivatives include 
4-pentadecylsalicylic acid, 3,5-di(.alpha.-methylbenzyl)-salicylic acid, 
3,5-di(ter-octyl)salicylic acid, 5-octadecylsalicylic acid, 
5-.alpha.-(p-.alpha.-methylbenzylphenyl)-ethylsalicylic acid, 
3-.alpha.-methylbenzyl-5-ter-octyl-salicylic acid, 5-tetradecylsalicylic 
acid, 4-hexyloxysalicylic acid, 4-cyclohexyloxysalicylic acid, 
4-decyloxysalicylic acid, 4-dodecyloxysalicylic acid, 
4-pentadecyloxysalicylic acid, 4-octadecyloxysalicylic acid and the like, 
and zinc, aluminum, calcium, copper and lead salts of these salicylic acid 
compounds. These electron accepting compounds are preferably used in an 
amount of from 5 to 1000% by weight on the basis of the electron donating 
colorless dye. 
The photo-hardenable composition of a negative recording material of the 
present invention may contain a monomer which has at least one vinyl group 
in the molecule. Such a monomer may be selected, for example, from acrylic 
acid and its salts, acrylic esters, acrylamides, methacrylic acid and its 
salts, methacrylic esters, methacrylamides, maleic anhydride, maleic 
esters, itaconic acid, itaconic esters, styrenes, vinyl ethers, vinyl 
esters, heterocyclic N-vinyl compounds, aryl ethers, allyl esters and the 
like. 
Of these, a monomer having a plurality of vinyl groups in the molecule is 
preferably used. Such a compound is selected, for example, from acrylic 
esters and methacrylic esters of polyhydric alcohols such as 
trimethylolpropane and pentaerythritol; epoxy resins with acrylate or 
methacrylate terminals; polyesters with acrylate or methacrylate terminals 
and the like, with most preferable compounds including ethylene glycol 
diacrylate, ethylene glycol dimethacrylate, trimethylolpropane 
triacrylate, pentaerythritol tetraacrylate, dipentaerythritol 
hydroxypentaacrylate, hexanediol-1,6-dimethacrylate, diethylene glycol 
dimethacrylate and the like. 
The molecular weight of the multifunctional monomer is preferably in the 
range of from about 100 to about 5,000, more preferably from about 300 to 
about 2,000. 
In addition to these compounds, polyvinyl cinnamate, polyvinyl 
cinnamylideneacetate, a photo-hardenable composition with an 
.alpha.-phenylmaleimide group or the like may be used as a photo 
cross-linkable composition. The a photo cross-linkable composition may 
also be used as a photo-hardenable composition. 
In addition to the above components, if desired, a heat polymerization 
inhibitor may also be added to the photo-hardenable composition. Such an 
inhibitor improves the chemical stability of the photo-hardenable 
composition during its preparation and storage because of the effect of 
the inhibitor to prevent thermal or time-dependent polymerization of the 
photo-hardenable composition. Illustrative examples of heat polymerization 
inhibitors include p-methoxyphenol, hydroquinone, t-butyl catechol, 
pyrogallol, 2-hydroxybenzophenone, 4-methoxy-2-hydroxybenzophenone, 
cuprous chloride, phenothiazine, chloranil, naphthylamine, 
.beta.-naphthol, 2,6-di-t-butyl-p-cresol, nitrobenzene, dinitrobenzene, 
picric acid, p-toluidine and the like. 
The heat polymerization inhibitor is preferably used in an amount of from 
0.001 to 5% by weight, more preferably from 0.01 to 1% by weight, based on 
the total weight of the photo-hardenable composition. If the amount of the 
inhibitor is smaller than 0.001% by weight, this results in inferior heat 
stability and if the amount is larger than 5% by weight sensitivity is 
reduced. 
When required, the photo-hardenable composition of the recording material 
of the present invention may be used by including it in microcapsules. 
Inclusion of the composition in microcapsules may be carried out by 
reference, for instance, to European Patent No. 0,223,587 and other 
patents described above. 
Various known compounds are useful as the electron donating colorless dye 
used in the recording material of the present invention, such as 
triphenylmethanephthalide compounds, fluoran compounds, phenothiazine 
compounds, indolylphthalide compounds, leucoauramine compounds, rhodamine 
lactam compounds, triphenylmethane compounds, triazene compounds, 
spiropyran compounds, fluorene compounds and other compounds. Illustrative 
examples of these compounds are disclosed, for instance: phthalide 
compounds in U.S. Reissue Pat. No. 23,024, U.S. Pat. No. 3,491,111, U.S. 
Pat. No. 3,491,112, U.S. Pat. No. 3,491,116 and U.S. Pat. No. 3,509,174; 
fluoran compounds in U.S. Pat. No. 3,624,107, U.S. Pat. No. 3,627,787, 
U.S. Pat. No. 3,641,011, U.S. Pat. No. 3,462,828, U.S. Pat. No. 3,681,390, 
U.S. Pat. No. 3,920,510 and U.S. Pat. No. 3,959,571; spirodipyran 
compounds in U.S. Pat. No. 3,971,808; pyridine and pyrazine compounds in 
U.S. Pat. No. 3,775,424, U.S. Pat. No. 3,853,869 and U.S. Pat. No. 
4,246,318; and fluorene compounds in Japanese Patent Application No. 
61-240989 (corresponding to U.S. patent application Ser. No. 07/567,040). 
Illustrative examples of these compounds include: triarylmethane compounds 
such as 3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide, 
3,3-bis(p-dimethylaminophenyl)phthalide, 
3-(p-dimethylaminophenyl)-3-(1,3-dimethylindole-3-yl)phthalide, 
3-(p-dimethylaminophenyl)-3-(2-methylindole-3-yl)phthalide and the like; 
diphenylmethane compounds such as 4,4'-bis-dimethylaminobenzhydrin benzyl 
ether, N-halophenylleucoauramine, N-2,4,5-trichlorophenylleucoauramine and 
the like; xanthene compounds such as Rhodamine B anilinolactam, 
Rhodamine-(p-nitrino)-lactam, 2-(dibenzylamino)fluoran, 
2-anilino-3-methyl-6-diethylaminofluoran, 2-anilino 
3-methyl-6-dibutylaminofluoran 
2-anilino-3-methyl-6-N-ethyl-N-isoamylaminofluoran, 
2-anilino-3-methyl-6-N-methyl-N-cyclohexylaminofluoran, 
2-anilino-3-chloro-6-diethylaminofluoran, 
2-anilino-3-methyl-6-N-ethyl-N-isobutylaminofluoran, 
2-anilino-6-dibutylaminofluoran, 
2-anilino-3-methyl-6-N-methyl-N-tetrahydrofurfurylaminofluoran, 
2-anilino-3-methyl-6-piperidinoaminofluoran, 
2-(o-chloroanilino)-6-diethylaminofluoran, 
2-(3,4-dichloroanilino)-6-diethylaminofluoran and the like; thiazine 
compounds such as benzoyl Leucomethylene Blue, p-nitrobenzyl 
Leucomethylene Blue and the like; spiropyran compounds such as 
3-methyl-spiro-dinaphthopyran, 3-ethyl-spirodinaphthopyran, 
3,3'-dichloro-spiro-dinaphthopyran, 3-benzylspiro-dinaphthopyran, 
3-methyl-naphtho-(3-methoxy-benzo)spiropyran, 3-propyl-spiro-dibenzopyran 
and the like; and many other related compounds. 
When electron donating colorless dyes are used in a full-color recording 
material, useful examples of dyes for use in cyan, magenta and yellow 
color development are disclosed, instance, in U.S. Pat. No. 4,800,149, 
those for yellow color development, for instance, in U.S. Pat. No. 
4,800,148 and those for cyan use, for instance, in JP-A-63-53542. 
The electron donating colorless dye used in the recording material of the 
present invention can be included in microcapsules using well known 
techniques such as methods disclosed in U.S. Pat. No. 2,800,457 and U.S. 
Pat. No. 2,800,458, in which coacervation of a hydrophilic wall forming 
material is employed; interfacial polymerization methods disclosed in U.S. 
Pat. No. 3,287,154, British Patent 990,443, JP-B-38-19574, JP-B-42-446 and 
JP-B-42-771; polymer precipitation methods disclosed in U.S. Pat. No. 
3,418,250 and U.S. Pat. No. 3,660,304; a method disclosed in U.S. Pat. No. 
3,796,669 in which an isocyanate polyol is used as a wall forming 
material; a method disclosed in U.S. Pat. No. 3,914,511 in which an 
isocyanate compound is used as a wall forming material; methods disclosed 
in U.S. Pat. No. 4,001,140, U.S. Pat. No. 4,087,376 and U.S. Pat. No. 
4,089,802 in which a urea-formaldehyde system or a 
urea-formaldehyde-resorcinol system is used as a wall forming material; a 
method disclosed in U.S. Pat. No. 4,025,455 in which a 
melamine-formaldehyde resin, a hydroxypropyl cellulose or the like is used 
as a wall forming material; in situ monomer polymerization methods 
disclosed in JP-B-36-9168 and JP-A-51-9079; electrolytic dispersion 
cooling methods disclosed in British Patent 952,807 and British Patent 
965,074; and spray drying methods disclosed in U.S. Pat. No. 3,111,407 and 
British Patent 930,422. Although not restricted, it is preferable to form 
polymer membranes as microcapsule walls after completion of core material 
emulsification. 
The microcapsule wall of the microcapsules used in the present invention 
may be prepared effectively especially by the use of a method in which the 
wall is formed by polymerization of a reactant inside an oil drop. With 
such a method, capsules having a homogeneous particle size and excellent 
shelf life as a recording material can be obtained quickly. 
For example, in the case of the use of polyurethane as the capsule wall 
material, microcapsule walls may be prepared by mixing a polyvalent 
isocyanate and, if necessary, a second material which forms a capsule wall 
by reacting with the isocyanate (for example, a polyol or a polyamine) 
with an oily liquid to be incorporated into the capsules, emulsifying and 
dispersing the resulting mixture in water and then increasing temperature 
of the emulsified dispersant to initiate the polymer formation reaction at 
the interface of oil drops. In this instance, an auxiliary solvent having 
a low boiling point and a high solubility may be added to the oily liquid. 
Examples of polyvalent isocyanates, polyols and polyamines useful for this 
purpose are disclosed in U.S. Pat. No. 3,281,383, U.S. Pat. No. 3,773,695, 
U.S. Pat. No. 3,793,268, JP-B-48-40347, JP-B-49-24159, JP-A-48-80191 and 
JP-A-48-84086. 
Illustrative examples of polyvalent isocyanates include: diisocyanates such 
as m-phenylenediisocyanate, p-phenylenediisocyanate, 
2,6-tolylenediisocyanate, 2,4-tolylenediisocyanate, 
naphthalene-1,4-diisocyanate, diphenylmethane-4,4'-diisocyanate, 
3,3'-dimethoxy-4,4'-biphenyldiisocyanate, 
3,3'-dimethyldiphenylmethane-4,4'-diisocyanate, xylylene-1,4-diisocyanate, 
4,4'-diphenylpropanediisocyanate, trimethylenediisocyanate, 
hexamethylenediisocyanate, propylene-1,2-diisocyanate, 
butylene-1,2-diisocyanate, cyclohexylene-1,2-diisocyanate, 
cyclohexylene-1,4-diisocyanate and the like; triisocyanates such as 4,4', 
4"-triphenylmethanetriisocyanate, toluene-2,4,6-triisocyanate and the 
like; tetraisocyanates such as 
4,4'-dimethyldiphenylmethane-2,2',5,5'-tetraisocyanate and the like; and 
isocyanate prepolymers such as an addition product of 
hexamethylenediisocyanate and trimethylolpropane, an addition product of 
2,4-tolylenediisocyanate and trimethylolpropane, an addition product of 
xylylenediisocyanate and trimethylolpropane, an addition product of 
tolylenediisocyanate and hexanetriol and the like. 
Illustrative examples of polyols include aliphatic and aromatic polyhydric 
alcohols, hydroxy polyesters, hydroxypolyalkylene ethers and the like. 
The polyols disclosed in JP-A-60-49991 are also useful such as 
ethyleneglycol, 1,3-propanediol, 1,4-butanediol, 1,5-pentanediol, 
1,6-hexanediol, 1,7-heptanediol, 1,8-octanediol, propyleneglycol, 
2,3-dihydroxybutane, 1,2-dihydroxybutane, 1,3-dihydroxybutane, 
2,2-dimethyl-1,3-propanediol, 2,4-pentanediol, 2,5-hexanediol, 
3-methyl-1,5-pentanediol, 1,4-cyclohexanedimethanol, dihydroxycyclohexane, 
diethyleneglycol, 1,2,6-trihydroxyhexane, 2-phenylpropyleneglycol, 
1,1,1-trimethylolpropane, hexanetriol, pentaerythritol, a pentaerythritol 
ethylene oxide addition product, a glycerol ethylene oxide addition 
product, glycerol, 1,4-di(2-hydroxyethoxy)benzene, a condensed product of 
alkylene oxide and an aromatic polyhydric alcohol such as resorcinol 
dihydroxyethyl ether or the like, p-xylyleneglycol, m-xylyleneglycol, 
.alpha.,.alpha.'-dihydroxy-p-diisopropylbenzene, 
4,4'-dihydroxydiphenylmethane, 
2-(p,p'-dihydroxydiphenylmethyl)benzylalcohol, an addition product of 
bisphenol A with ethylene oxide, an addition product of bisphenol A with 
propylene oxide and the like. Each polyol may be used in an amount such 
that its hydroxyl groups are 0.02 to 2 mols per one mol of isocyanate 
group. 
Illustrative examples of polyamines which can be used in the present 
invention include ethylenediamine, trimethylenediamine, 
tetramethylenediamine, pentamethylenediamine, hexamethylenediamine, 
p-phenylenediamine, m-phenylenediamine, piperazine, 2-methylpiperazine, 
2,5-dimethylpiperazine, 2-hydroxytrimethylenediamine, diethylenetriamine, 
triethylenetriamine, triethylenetetramine, diethylaminopropylamine, 
tetraethylenepentamine, amine-added products of epoxy compounds and the 
like. Polyisocyanates can be converted into high molecular weight 
compounds through reaction with water. 
Water soluble polymers are useful for the preparation of microcapsules as a 
protective colloid in the emulsification and dispersion step. In this 
instance, any of anionic, nonionic and amphoteric water soluble polymers 
are suitable. 
Suitable water soluble anionic polymers include both natural and synthetic 
polymers which, for example, have an --COO.sup.- group, a --SO.sub.2.sup.- 
group and the like. Illustrative examples of water soluble anionic 
polymers include: natural polymers such as gum arabic, alginic acid, 
pectin and the like; semi-synthetic polymers such as carboxymethyl 
cellulose, phthalated gelatin, sulfated starch, sulfated cellulose, lignin 
sulfonate and the like; and synthetic polymers such as copolymers of 
maleic anhydride (including hydrolyzed products), polymers and copolymers 
of acrylic acid (including methacrylic acids), polymers and copolymers of 
vinylbenzenesulfonate, carboxy-modified polyvinyl alcohol and the like. 
Suitable water soluble nonionic polymers, indicate polyvinyl alcohol, 
hydroxyethyl cellulose, methyl cellulose and the like. 
Gelatin and the like are suitable as water soluble amphoteric polymers. 
However, since the polyvalent isocyanate reacts with amino groups of 
gelatin very quickly, when gelatin as the protective colloid and the 
polyvalent isocyanate as the reactant to form the capsule wall are used in 
combination, the reaction between the isocyanate and the amino groups of 
gelatin occurs at the beginning of the emulsification and dispersion step 
and flocculation occurs. In order to avoid such flocculation, it is 
preferred to use a modified gelatin, i.e., a gelatin where the amino 
groups are selectively replaced by another group which does not react with 
the isocyanate. Specific examples of the modified gelatin include a 
phthalate modified gelatin, an acetylate modified gelatin, an oxalate 
modified gelatin, a malonate modified gelatin, a succinate modified 
gelatin, a glutarate modified gelatin, an adipate modified gelatin, a 
pimelate modified gelatin, a maleate modified gelatin, a fumarate modified 
gelatin, a benzoylate modified gelatin, and the like. Among them, a 
phthalate modified gelatin and a succinate modified gelatin are preferred. 
A modification ratio of these modified gelatins is 50% by mol or more, 
preferably 80% by mole or more, more preferably 95% by mole or more, based 
on the total amino groups of gelatin. 
These water soluble polymers may be used as an aqueous solution of 0.01 to 
15% by weight. 
The size of capsules suitable for use in the recording material of the 
present invention may be 20 .mu.m or less, preferably 5 .mu.m or less, 
more preferably 2 .mu.m or less. If the capsule size is too small, 
however, an unnecessarily large amount of wall material is required 
because the surface area per solid material is large. The capsule size, 
therefore, is preferably 0.1 .mu.m or larger. 
The electron donating colorless dye of the present invention may be present 
in the microcapsules in either a liquid or a solid form. When the electron 
donating colorless dye is used in a liquid form, it may be present in the 
capsules dissolved in a solvent. In this instance, the amount of the 
solvent is in the range of from 1 to 500 parts by weight based on 100 
parts by weight of the electron donating colorless dye. 
According to the present invention, when microcapsules are prepared, a 
single or a combination of volatile solvents which have a water solubility 
of 10% by volume or less measured at 25.degree. C. and have a low boiling 
point such that they volatilize during the process for preparing the 
light-sensitive heat-sensitive recording material leaving substantially no 
trace of the solvent in the resulting recording material is preferably 
used as a solvent system of the microcapsule core material, namely, at 
least one component capable of undergoing color development or 
achromatization such as an electron donating colorless dye. Since the 
volatile solvents volatilize almost completely during the microcapsule 
preparation step and following coating and drying steps and therefore are 
substantially eliminated from the resulting recording material, 
evaporation of organic substances does not occur when the recording 
material of the present invention is subjected to heating for heat 
development. The term "substantially no trace of the solvent" as used 
herein means that the amount of the solvent in the resulting recording 
material is very low in an extent that it cannot be detected by means of a 
gas chromatography. 
Commonly used high boiling point solvents may be used for the dissolution 
of core materials during microcapsule preparation in combination with the 
volatile solvent so long as the effects of the present invention are not 
deteriorated thereby. 
The term "high boiling point solvent" as used herein is a solvent which is 
volatilized slowly during the process for the production of the 
light-sensitive heat-sensitive recording material, so that it remains in 
the resulting recording material in an amount, say 0.1 g/m.sup.2 or more 
which can not be ignored. Such high boiling point solvents include natural 
or synthetic oil having a boiling point of 101.degree. C. or higher, 
though the remaining amount cannot be defined specifically because it 
depends on the relationship between the boiling point of the solvent to be 
used and temperatures at the time of the capsule preparation and drying 
steps during which the solvent is evaporated. Examples of such solvents 
are cotton seed oil, kerosene, an aliphatic ketone, an aliphatic ester, 
paraffin, naphthene oil, an alkylated biphenyl, an alkylated terphenyl, a 
chlorinated paraffin, an alkylated naphthalene, a diarylethane, a phthalic 
acid alkyl ester, a phosphoric ester, a citric ester, a benzoic ester and 
the like, all of them having a boiling point of 101.degree. C. or higher. 
In addition, where a solvent having a boiling point of 100.degree. C. or 
lower is used, a highly water soluble solvent such as methanol, acetone or 
the like is not very preferred as a solvent for use in the dissolution of 
a core material at the time of microcapsule preparation, because the core 
material precipitates in water and therefore cannot be emulsified. The 
present inventors have conducted intensive studies and found that 
excellent results can be obtained by the use of a solvent having a water 
solubility of 10% by volume or less. 
The volatile solvent to be used in the present invention, which has a water 
solubility of 10% by volume or less and has a low boiling point such that 
it volatilizes during a process for preparing said light-sensitive 
heat-sensitive recording material leaving substantially no trace of the 
solvent in the resulting recording material, is preferably selected from 
solvents having a boiling point of 100.degree. C. or lower. Preferred 
examples of such solvents include ethyl acetate, isopropyl acetate, 
t-butyl acetate, vinyl acetate, methylisobutyrate, methylacrylate, 
methylenechloride, carbon tetrachloride and the like, of which ethyl 
acetate, isopropyl acetate and methylenechloride are particularly 
preferred. 
A matting agent is preferably included in the protective layer of the 
recording material of the present invention. Examples of matting agents 
include: inorganic compounds such as silica, magnesium oxide, barium 
sulfate, strontium sulfate, silver halide and the like; polymer particles 
such as those of polymethylmethacrylate, polyacrylonitrile, polystyrene 
and the like; and starch particles such as of carboxylated starch, corn 
starch, carboxynitrophenyl starch and the like, of which a particle size 
ranges from 1 to 20 .mu.m. Among these matting agents, 
polymethylmethacrylate particles and silica particles are particularly 
preferred. Preferable silica particles are Siloid AL-1, 65, 72, 79, 74, 
404, 620, 308, 978, 161, 162, 244, 255, 266, 150 and the like which are 
available from FUJI-DEVISON CHEMICAL, LTD. The matting agent is used 
preferably in an amount of from 2 to 500 mg/m.sup.2, more preferably from 
5 to 100 mg/m.sup.2. 
A curing agent is preferably used jointly in each of the layers of the 
recording material such as a light-sensitive heat-sensitive layer, an 
intermediate layer, a protective layer and the like, especially in the 
protective layer in order to reduce the stickiness of this layer in the 
recording material of the present invention. The so-called "gelatin curing 
agent" which is used for the production of photographic materials are 
useful as the curing agent. Examples of the curing agent include: aldehyde 
compounds such as formaldehyde, glutaraldehyde and the like; compounds 
having reactive halogens disclosed, for instance, in U.S. Pat. No. 
3,635,718; compounds having reactive ethylenically unsaturated bonds 
disclosed, for instance, in U.S. Pat. No. 3,635,718; azilidine-based 
compounds disclosed, for instance, in U.S. Pat. No. 3,017,280; epoxy 
compounds disclosed, for instance, in U.S. Pat. No. 3,091,537; 
halogenocarboxyaldehydes such as mucochloric acid and the like; dioxanes 
such as dihydroxydioxane, dichlorodioxane and the like; vinyl sulfones 
disclosed, for instance, in U.S. Pat. No. 3,642,486 and U.S. Pat. No. 
3,687,707; vinyl sulfone precursors disclosed in U.S. Pat. No. 3,841,872; 
keto vinyls disclosed in U.S. Pat. No. 3,640,720; and chrome alum, 
zirconium sulfate, boric acid and the like as inorganic curing agents. Of 
these curing agents, the most preferred compounds are 
1,3,5-triacroyl-hexahydro-s-triazine, 1,2-bis-vinylsulfonylmethane, 
1,3-bis(vinylsulfonylmethyl)propanol-2, 
bis(.alpha.-vinylsulfonylacetamide)ethane, sodium 
2,4-dichloro-6-hydroxy-s-triazine, 2,4,6-triethyleneimino-s-triazine, 
boric acid and the like. These compounds are used preferably in an amount 
of from 0.5 to 5% by weight based on the binder used. 
In addition to these compounds, the protective layer may contain colloidal 
silica in order to reduce the stickiness of the layer. Snowtex 20, Snowtex 
30, Snowtex C, Snowtex O, Snowtex N and the like manufactured by Nissan 
Chemical Industries, Ltd. can be used preferably. The colloidal silica may 
be used preferably in an amount of from 5 to 80% by weight based on the 
binder. 
The protective layer may also include a fluorescent whitening agent and a 
blue dye as a blueing agent in order to increase the brightness of the 
recording material of the present invention. 
In use of the recording material of the present invention as a multicolor 
recording material, the recording material may be made into multilayers 
which comprise light-sensitive heat-sensitive layers each containing 
microcapsules in which an electron donating colorless dye that develops a 
different hue a photo-hardenable composition having a different wave 
length sensitivity and, preferably, an intermediate layer containing a 
UV-absorbing agent interposed between these light-sensitive heat-sensitive 
layers. 
The intermediate layer contains mainly a binder and a UV-absorbing agent 
and, if desired, additive such as a curing agent, a polymer latex and the 
like. 
Any compound known in the art is useful as a UV-absorbing agent, such as a 
benzotriazole compound, a cinnamic ester compound, an aminoallylidene 
malonitrile compound, a benzophenone compound or the like. 
The UV-absorbing agent to be used in the recording material of the present 
invention may be added to any layers as desired, especially to 
intermediate layers, after emulsifying and dispersing the agent using an 
oil drop dispersion method in water or a polymer dispersion method. In the 
case of the oil drop dispersion method, the UV-absorbing agent is 
initially dissolved in a high boiling point organic solvent having a 
boiling point of, for example 175.degree. C. or higher, or in a so-called 
auxiliary solvent having a boiling point of, for example, from 30.degree. 
to 160.degree. C. or in a mixture thereof, and then dispersed in an 
aqueous medium such as water, an aqueous solution of gelatin, an aqueous 
solution of polyvinyl alcohol or the like in the presence of a surface 
active agent. Examples of high boiling point organic solvents are 
disclosed, for instance, in U.S. Pat. No. 2,322,027. Illustrative examples 
of high boiling point organic solvents and auxiliary solvents include the 
solvents for use in the preparation of microcapsules described above. The 
dispersion step may involve phase inversion. If necessary, the auxiliary 
solvent may be removed or reduced prior to coating using distillation, 
noodle washing, ultrafiltration and the like. 
The procedures and effects of the latex dispersion method and illustrative 
examples of impregnation latexes are disclosed, for instance, in U.S. Pat. 
No. 4,199,363, OLS (German Patent Application) 2,541,274, OLS 2,541,230, 
JP-A-49-74538, JP-A-51-59943 and JP-A-54-32552, as well as in Research 
Disclosure, vol. 148, August, 1976, Item 14850. Suitable latexes for use 
in the present invention are a copolymer latex made of, for instance, an 
acrylic or a methacrylic ester (ethylacrylate, n-butylacrylate, 
n-butylmethacrylate, 2-acetoacetoxyethylmethacrylate or the like) and an 
acid monomer (acrylic acid, 2-acrylamide-2-methylpropanesulfonic acid or 
the like). 
The most preferable UV-absorbing agent for use in the recording material of 
the present invention has a structure such that it hardly diffuses into 
the adjoining layer, a structure such as a polymer or a latex 
copolymerized with an UV-absorbing agent. These types of UV-absorbing 
agents are disclosed, for example, in European Patent 127,819, 
JP-A-59-68731, JP-A-59-26733, JP-A-59-23344, British Patent 2,118,315, 
JP-A-58-111942, U.S. Pat. No. 4,307,184, U.S. Pat. No. 4,202,836, U.S. 
Pat. No. 4,202,834, U.S. Pat. No. 4,207,253, U.S. Pat. No. 4,178,303, 
JP-A-47-560. 
These UV-absorbing agents are added to an intermediate layer but, if 
desired, may be added to a protective layer, a light-sensitive 
heat-sensitive layer, an anti-halation layer and the like. 
In the preparation of the recording material of the present invention, 
dispersion of the photo-hardenable composition and dispersion of the 
component(s) capable of undergoing color development or achromatization 
which are not microencapsulated are carried preferably using a water 
soluble polymer. Water soluble polymers suitable for use in the resent 
invention have a solubility of 5% by weight or more in water at 25.degree. 
C. Preferred examples of such water soluble polymers include gelatin and 
gelatin derivatives. Further, another water soluble polymers such as 
proteins (e.g., albumin, casein and the like), cellulose derivatives 
(e.g., a methyl cellulose, a carboxymethyl cellulose and the like) sugar 
derivatives (e.g., a sodium alginate, a starch (including modified 
starches) and the like) gum arabic, synthetic polymers (e.g., a polyvinyl 
alcohol, a hydrolyzed product of a styrene-maleic anhydride copolymer, a 
carboxy-modified polyvinyl alcohol, a polyacryl amide, a saponified 
product of a vinyl acetate-polyacrylic acid copolymer, a polystyrene 
sulfonate and the like, can be used in combination with gelatin or the 
gelatin derivatives. 
With regard to a binder to be added to each of the protective layer, 
light-sensitive heat-sensitive layer, intermediate layer and the like of 
the recording material of the present invention, the above-described water 
soluble polymers are also be useful, as well as solvent soluble polymers 
which include, for example, polystyrene, polyvinyl formal, polyvinyl 
butyral, acrylic resins such as polymethylacrylate, polybutylacrylate, 
polymethylmethacrylate, polybutylmethacrylate and their copolymers, phenol 
resins, styrene-butadiene resins, ethyl cellulose, epoxy resins, urethane 
resins and polymer latexes of these solvent soluble polymers, with most 
preferable polymers being gelatin and polyvinyl alcohol. 
Various surfactants may be used in the recording material of the present 
invention, for example, as a coating aid, preventing electro static 
charging, improving sliding ability, enhancing emulsification and 
dispersion, preventing adhesion and the like. Such surfactants may be 
selected depending on the purpose from, for example: nonionic surfactants 
including saponin, polyethylene oxides and derivatives of polyethylene 
oxides such as a polyethylene oxide alkyl ether; anionic surfactants 
including alkyl sulfonates, alkylbenzene sulfonates, alkylnaphthalene 
sulfonates, alkyl sulfate esters, N-acyl-N-alkyltaurines, sulfosuccinate 
esters, sulfoalkylpolyoxyethylene alkylphenyl ether and the like; 
ampholytic surfactants including alkylbetaines, alkylsulfobetaines and the 
like; and cationic surfactants including aliphatic or aromatic quaternary 
ammonium salts and the like. 
In addition to the above described additives, many other agents may be 
added, if desired, to the recording material of the present invention. 
Typical examples of the additive include irradiation- and 
halation-preventing dyes, UV-absorbing agents, plasticizers, fluorescent 
whitening agents, matting agents, coating aids, curing agents, antistatic 
agents, sliding improvers and the like as disclosed, for instance, in 
Research Disclosure, vol. 176, Item 17643 (December, 1978) and Research 
Disclosure, vol. 187, Item 18716 (November 1979). 
The recording material of the present invention can be obtained by 
preparing coating solutions for use in the light-sensitive heat-sensitive 
layer and other layers dissolved in a suitable solvent, and coating and 
drying the coating solutions on an appropriate support. Solvents suitable 
for use for this purpose include: water; alcohols such as methanol, 
ethanol, n-propanol, isopropanol, n-butanol, sec-butanol, methyl 
cellosolve, 1-methoxy-2-propanol and the like; halogen based solvents such 
as methylene chloride, ethylene chloride and the like; ketones such as 
acetone, cyclohexanone, methyl ethyl ketone and the like; esters such as 
methyl cellosolve acetate, ethyl acetate, methyl acetate and the like; and 
toluene, xylene and the like; of which water is particularly preferred. 
These solvents may be used alone or as a mixture of two or more thereof. 
Application of the coating solution to a support may be effected by the use 
of a blade coater, a rod coater, a knife coater, a roll doctor coater, a 
reverse roll coater, a transfer roll coater, a gravure coater, a kiss roll 
coater, a curtain coater, an extrusion coater or the like. Suitable 
application methods are disclosed, for example, in Research Disclosure, 
vol. 200, Item 20036 XV (December, 1980). 
Further, application of the coating solutions to a support may also be 
effected by a simultaneous multicoating technique when the modified 
gelatin is employed as a protective colloid for preparing microcapsules 
containing at least one component capable of undergoing color development 
or achromatization, and all of the coating solutions are formulated in a 
gelatin system. Suitable simultaneous multicoating methods include a 
method described in Shashin Kogaku no Kiso, Ginen Shashin Hen (Basis of 
Photograph Engineering, Volume for Silver Halide Photographic), edited by 
the Society of Photographic science and Technology of Japan, the third 
captor; a multi-slide method as disclosed in U.S. Pat. No. 3,206,323; a 
curtain flow method as disclosed in U.S. Pat. No. 3,508,947; and the like. 
The thickness of the light-sensitive heat-sensitive recording layer is 
preferably in the range of from 0.1 .mu.m to 50 .mu.m. 
The recording material of the present invention can be used in applications 
such as a copying machine, a facsimile, a printer, a label, a color proof, 
an overhead projector, a secondary drawing and the like. Examples of 
suitable supports for these applications include paper materials such as 
paper, coated paper, laminated paper, synthetic paper and the like; 
transparent films such as polyethylene terephthalate film, cellulose 
triacetate film, polyethylene film, polystyrene film, polycarbonate film 
and the like; and metal plates such as those of aluminium, zinc, copper 
and the like; as well as modified products of these supports in which the 
surface of each material is treated using various techniques such as 
surface treatment, subbing, metal vaporization and the like. Also useful 
are those supports disclosed in Research Disclosure, vol. 200, Item 20036 
XVII (December, 1980). A preferred thickness for these supports is in the 
range of from 50 to 200 .mu.m. 
These supports may be provided with a flatting surface layer on the front 
surface to cover and flatten unevenness of the surface of the support. The 
flatting surface layer may be formed by applying a polymer binder on the 
surface of the support in a conventional technique. As to the polymer 
binder, any of those having film-forming property can be used. Among them, 
gelatin is advantageous because application of the coating solutions to 
the support can be effected by the simultaneous multicoating technique 
when gelatin is selected as the material for the flatting surface layer. 
The thickness of the flatting surface layer preferably ranges from 0.2 to 
10 .mu.m. When it is thinner than the range, unevenness of the surface of 
the support is not sufficiently flattened. On the other hand, when it is 
thicker than the range, a large amount of the material is required to form 
it, thus it is disadvantageous. 
These base materials for support use may be used after whitening by filling 
or coating them with a pigment. 
Examples of pigments for filling purpose include silica, titanium dioxide, 
barium sulfate, calcium sulfate, barium carbonate, calcium carbonate, 
lithophone alumina white, zinc oxide, antimony trioxide, titanium 
phosphate and the like. These pigments may be used alone or as a mixture 
of two or more. Preferably, these pigments have a particle size of from 
0.1 to 8 .mu.m, and are used in an amount of from 1 to 30% based on the 
weight of the base material. For the purpose of dispersing these pigments 
in a resin, a metal soap such as zinc stearate, aluminium stearate or the 
like or other surface active agent is used as a dispersant. 
These pigments are also useful for whitening by surface coating. Many water 
soluble, water dispersible and non-aqueous binders are useful in the 
preparation of support. These binders may be selected from those disclosed 
in Saishin Bainda Gijutsu Binran (Recent Binder Technique Manual) 
published by Sogo Gijutsu Center (in Japanese). 
Examples of water soluble binders include gelatin, PVA, casein and the 
like, which are preferably used jointly with a curing agent. Useful water 
dispersible binders include butadiene copolymer latex, vinyl acetate resin 
emulsion, acryl emulsion, polyolefin-based emulsion and the like. As for 
non-aqueous binders, polyester-based, vinyl acetate-based, thermoplastic 
elastomer-based, polyurethane-based, melamine-based, urea-based, 
alkyd-based, acryl-based and phenol-based binders can be used. 
In addition, these supports may be coated with additional layers depending 
on the purpose, such as an anti-halation layer on the front surface and a 
sliding layer, an anti-static layer, a curl-prevention layer, an adhesive 
layer and the like on the back surface. 
Since the recording material of the present invention has a high recording 
sensitivity over a broad range of wave lengths from ultraviolet light to 
visible light, various light sources can be used such as a mercury lamp, 
an ultra-high pressure mercury lamp, a mercury lamp of electrodeless 
discharge type, a xenon lamp, a tungsten lamp, a metal halide lamp, 
various lasers including argon laser, helium neon laser, semi-conductor 
laser and the like, as well as LED, a fluorescent lamp and other light 
sources for exposure. 
Image recording can be performed by various means including contact 
exposure of copies such as a lith film, enlarged exposure of slides, 
liquid crystal images and the like, reflection exposure using reflected 
light from an original image, and other exposure means. Multicolor 
recording may be effected by single or multiple image recording using 
different wave lengths. Different wave lengths may be obtained either by 
changing light sources or by changing the optical filters. 
A heat developing treatment is carried out simultaneously with or after the 
aforementioned image exposure of the recording material of the present 
invention. Many commonly used heating methods can be employed for the heat 
developing treatment. The heating temperature may generally be in the 
range of from 80.degree. to 200.degree. C., preferably from 100.degree. to 
160.degree. C. The heating time may be in the range of from 1 second to 5 
minutes, preferably from 3 seconds to 1 minute. 
After the heat developing treatment, it is preferable to perform a total 
area exposure to cure the uncured parts. By the total area exposure, the 
life of images can be improved because of the inhibition of coloring 
reaction on the uncolored portion and achromatization reaction on the 
colored portion.

Examples of the present invention are given below by way of illustration 
and not by way of limitation. Unless otherwise indicated herein, all 
parts, percents, ratios, and the like are by weight. 
EXAMPLES 1 TO 6 AND COMATIVE EXAMPLES 1 AND 2 
Preparation of Coating Solutions 
1-1 Preparation of capsules including electron donating colorless dye 
1-1-a Preparation of capsules including electron donating colorless dye (1) 
To 8.9 g of an electron donating colorless dye (1) dissolved in 16.9 g of 
ethyl acetate were added 20 g of Takenate D-110N (manufactured by Takeda 
Chemical Industries Ltd.) and 2 g of Millionate MR200 (manufactured by 
Nippon Polyurethane Industry Co., Ltd.) which are capsule-wall forming 
materials. The resulting solution was added to a mixture prepared from 42 
g of an 8% solution of phthalate modified gelatin and 1.4 g of a 10% 
solution of sodium dodecylbenzene sulfonate and then subjected to 
emulsification and dispersion at 20.degree. C. to obtain an emulsion. The 
thus obtained emulsion was mixed with 14 g of water and 72 g of a 2.9% 
aqueous solution of triethylenepentamine and heated at 60.degree. C. with 
stirring. After 2 hours of heating, a suspension of capsules in which the 
electron donating colorless dye (1) was incorporated was obtained, with a 
mean particle size of 0.5 .mu.m. When this suspension was filtrated 
through a filter mesh having a pore size of about 50 .mu.m, any residues 
were not observed. 
1-1-b Preparation of capsules including electron donating colorless dye 
A suspension of capsules having a mean particle size of 0.5 .mu.m in which 
an electron donating colorless dye (2) was incorporated was obtained by 
repeating the process of 1-1-a except that the electron donating colorless 
dye (1) used in 1-1-a was replaced by electron donating colorless dye (2). 
1-1-c Preparation of capsules including electron donating colorless dye (3) 
A suspension of capsules having a mean particle size of 0.5 .mu.m in which 
an electron donating colorless dye (3) was incorporated was obtained by 
repeating the process of 1-1-a except that the electron donating colorless 
dye (1) used in 1-1-a was replaced by electron donating colorless dye (3). 
1-1-d Preparation of capsules including electron donating colorless dye (3) 
and a high boiling point solvent 
A suspension of capsules having a mean particle size of 0.5 .mu.m in which 
the electron donating colorless dye (3) and 
trimethylolpropanetrimethacrylate as a high boiling point solvent were 
incorporated was obtained by repeating the process of 1-1-c except that 
10.4 g of ethyl acetate used in 1-1-c was replaced by a solvent mixture of 
10.4 g of ethyl acetate as a low boiling point solvent and 12.4 g of 
trimethylolpropanetrimethacrylate as a high boiling point solvent. 
1-2 Preparation of emulsion of photo-hardenable composition 
1-2-a Emulsion of photo-hardenable composition (1) 
In 3 g of isopropyl acetate were dissolved 0.13 g of a photopolymerization 
initiator (1), 0.1 g of a spectral sensitization dye (1) and 0.2 g of an 
auxiliary agent (1) to enhance polymerization. To this was added 5 g of a 
polymerizable electron accepting compound (1). The resulting solution was 
added to a mixture solution of 13 g of a 13% aqueous solution of gelatin, 
0.8 g of a 2% aqueous solution of a surface active agent (1) and 0.8 g of 
a 2% aqueous solution of a surface active agent (2). Thereafter, the 
resulting mixture was emulsified using a homogenizer (manufactured by 
Nippon Seiki Co., Ltd.) at 10,000 rpm for 5 minutes to obtain an emulsion 
of a photo-hardenable composition (1). 
1-2-b Emulsion of photo-hardenable composition (2) 
An emulsion of a photo-hardenable composition (2) was obtained by repeating 
the process of 1-2-a except that 0.13 g of the photopolymerization 
initiator (1) and 0.1 g of the spectral sensitization dye (1) used in 
1-2-a were replaced by 0.2 g of a photopolymerization initiator (2). 
1-2-c Emulsion of photo-hardenable composition (3) 
An emulsion of a photo-hardenable composition (3) was obtained by repeating 
the process of 1-2-a except that 0.13 g of the photopolymerization 
initiator (1) and 0.1 g of the spectral sensitization dye (1) used in 
1-2-a were replaced by 0.2 g of a photopolymerization initiator (3). 
1-2-d Emulsion of photo-hardenable composition (4) 
In 4 g of ethyl acetate were dissolved 0.2 g of the photopolymerization 
initiator (1), 0.2 g of the spectral sensitization dye (1) and 0.2 g of 
N-phenylglycine ethyl ester as an auxiliary agent to enhance 
polymerization. To this were added 10 g of (1-methyl-2-phenoxy)ethyl 
resorcinate as an electron accepting compound and 8 g of 
trimethylolpropanetriacrylate monomer. The resulting solution was added to 
a mixed solution of 19.2 g of a 15% aqueous solution of gelatin, 4.8 g of 
water, 0.8 g of a 2% aqueous solution of the surface active agent (1) and 
0.8 g of a 2% aqueous solution of the surface active agent (2). 
Thereafter, the resulting mixture was emulsified using a homogenizer 
(manufactured by Nippon Seiki Co., Ltd.) at 10,000 rpm for 5 minutes to 
obtain an emulsion of a photo-hardenable composition (4). 
1-3 Preparation of emulsion of UV-absorbing agent 
1-3-a Emulsion of UV-absorbing agents (1) and (2) 
In 17.5 g of ethyl acetate were dissolved 7.5 g of a UV-absorbing agent (1) 
and 2.4 g of another UV-absorbing agent (2). The resulting solution was 
added to a mixed solution of 62 g of a 15% aqueous solution of gelatin and 
1 g of a 62% aqueous solution of dodecylbenzenesulfonic acid. Thereafter, 
the resulting mixture was emulsificated using a homogenizer (manufactured 
by Nippon Seiki Co., Ltd.) at 10,000 rpm for 5 minutes to obtain an 
emulsion of UV-absorbing agents (1) and (2). 
1-3-b Emulsion of ultraviolet ray absorbing agent (3) 
A 5 g portion of an UV-absorbing agent (3) was dissolved in 19 g of ethyl 
acetate and the resulting solution was added to a mixed solution of 65 g 
of 15% aqueous solution of gelatin and 1 g of a 62% aqueous solution of 
dodecylbenzenesulfonic acid. Thereafter, the resulting mixture was 
emulsificated using a homogenizer (manufactured by Nippon Seiki Co., Ltd.) 
at 10,000 rpm for 5 minutes to obtain an emulsion of UV-absorbing agent 
(3). 
1-4 Preparation of coating solution for use in light-sensitive 
heat-sensitive layer 
1-4-a Coating solution for use in light-sensitive heat-sensitive layer (1) 
A coating solution for use in light-sensitive heat-sensitive layer (1) was 
prepared by mixing 4 g of the capsules which included the electron 
donating colorless dye (1), obtained in 1-1-a above, with 12 g of the 
emulsion of the photo-hardenable composition (1) obtained in 1-2-a above 
and 12 g of a 15% aqueous solution of gelatin. 
1-4-b Coating solution for use in light-sensitive heat-sensitive layer (2) 
A coating solution for use in light-sensitive heat-sensitive layer (2) was 
prepared by mixing 4 g of the capsules which included the electron 
donating colorless dye (2) with 12 g of the emulsion of the 
photo-hardenable composition (2) obtained in 1-1-b above and 12 g of a 15% 
aqueous solution of gelatin. 
1-4-c Coating solution for use in light-sensitive heat-sensitive layer (3) 
A coating solution for use in light-sensitive heat-sensitive layer (3) was 
prepared by mixing 4 g of the capsules which included the electron 
donating colorless dye (3) obtained in 1-1-c above with 12 g of the 
emulsion of the photo-hardenable composition (3) obtained in 1-2-c above 
and 12 g of a 15% aqueous solution of gelatin. 
1-4-d Coating solution for use in light-sensitive heat-sensitive layer (4) 
A coating solution for use in light-sensitive heat-sensitive layer (4) was 
prepared by mixing 1 g of the capsules which included the electron 
donating colorless dye (1) obtained in 1-1-a above with 10 g of the 
emulsion of the photo-hardenable composition (4) obtained in 1-2-d above. 
1-4-e Coating solution for use in light-sensitive heat-sensitive layer (3) 
containing a high boiling point solvent 
A coating solution for use in light-sensitive heat-sensitive layer (3) was 
prepared by mixing 4 g of the capsules which included the electron 
donating colorless dye (3) obtained in 1-1-b above and a high boiling 
point solvent with 12 g of the emulsion of the photo-hardenable 
composition (3) obtained in 1-2-c above and 12 g of 15% aqueous solution 
of gelatin. 
1-5 Preparation of coating solution for use in intermediate layer 
1-5-a Preparation of coating solution for use in intermediate layer (1) 
A coating solution for use in intermediate layer (1) was prepared by mixing 
9 g of distilled water with 14 g of the emulsion of the UV-absorbing 
agents (1), obtained in 1-3-a above, and (2) and 1.7 g of a 2% aqueous 
solution of a hardening agent (1). 
1-5-b Preparation of coating solution for use in intermediate layer (2) 
A coating solution for use in intermediate layer (2) was prepared by mixing 
9 g of distilled water with 14 g of the emulsion of the UV-absorbing agent 
(2), obtained in 1-3-b above, and 1.7 g of a 2% aqueous solution of the 
hardening agent (1). 
1-6 Preparation of coating solution for use in protective layer 
1-6-a Coating solution for use in protective layer (1) 
A coating solution for use in protective layer (1) was prepared by mixing 
4.5 g of a 10% aqueous solution of gelatin, 4.5 g of distilled water, 0.5 
g of a 2% aqueous solution of a surface active agent (3), 0.3 g of a 2% 
aqueous solution of a surface active agent (4), 0.5 g of a 2% aqueous 
solution of the hardening agent (1), a predetermined amount of Cycolloid 
72 (manufactured by Fuji-Devison Chemical Ltd.) and 1 g of Snowtex N 
(manufactured by Nissan Chemical Industries, Ltd.). Cycolloid 72 was used 
in such an amount that the coating amount was 50 mg/m.sup.2. 
EXAMPLE 1 
Positive Type Light-Sensitive Heat-Sensitive Recording Material 
The coating solution for use in light-sensitive heat-sensitive layer (1) 
obtained in 1-4-a above was coated on the surface of a polyethylene 
terephthalate film having a thickness of 100 .mu.m using a coating bar, in 
such an amount that the dry weight of the resulting layer was 8 g/m.sup.2 
and the coated solution was dried at 30.degree. C. for 10 minutes. The 
surface of the thus coated layer was further coated with the coating 
solution for use in intermediate layer (1) obtained in 1-5-a above in such 
an amount that the dry weight of the resulting intermediate layer was 2 
g/m.sup.2 and then dried. The surface of the thus coated first 
intermediate layer was further coated with the coating solution for use in 
light-sensitive heat-sensitive layer (2) obtained in 1-4-b above in such 
an amount that the dry weight of the resulting light-sensitive 
heat-sensitive layer was 8 g/m.sup.2 and then dried. The surface of the 
thus coated light-sensitive heat-sensitive layer was further coated with 
the coating solution for use in intermediate layer (2) obtained in 1-5-b 
above in such an amount that the dry weight of the resulting second 
intermediate layer became 2 g/m.sup.2 and then dried. The surface of the 
thus coated second intermediate layer was further coated with the coating 
solution for use in light-sensitive heat-sensitive layer (3) obtained in 
1-4-c above in such an amount that the dry weight of the resulting 
light-sensitive heat-sensitive layer was 8 g/m.sup.2 and then dried. 
Finally, the surface of the thus coated light-sensitive heat-sensitive 
layer was further coated with the coating solution for use in protective 
layer (1) obtained in 1-6-a above using a coating bar in such an amount 
that the dry weight of the resulting protective layer became 2 g/m.sup.2 
and then dried at 30.degree. C. for 10 minutes. In this way, the sample of 
Example 1 was obtained. 
Through a lith film on which an image for yellow had been developed and an 
optical filter which cut out light of 410 nm or below (SC-41 filter, 
manufactured by Fuji Photo Film Co., Ltd.), the thus prepared 
light-sensitive heat-sensitive recording material was exposed to 
ultraviolet light using a 2,000 W high frequency lighting type ultra-high 
pressure mercury lamp (Printer P627GA, manufactured by Dainippon Screen 
Co., Ltd.). The thus treated recording material was then exposed to light 
of the mercury lamp through a lith film on which an image for magenta had 
been developed and through an interference filter which transmits only 
light of a wavelength of 365 to 400 nm. The resulting recording material 
was further exposed to light of the mercury lamp through a lith film on 
which an image for cyan had been developed and through an interference 
filter which transmits only light of a wavelength of 340 to 365 nm. A 
latent image was obtained in this way. When the UV-exposed recording 
material was heated at 120.degree. C. for 5 seconds using a hot plate, a 
clear positive full-color image was obtained. The densities of the cyan, 
magenta and yellow in the non-image area were found to be 1.1, 1.2 and 
0.9, respectively. Since the image thus formed was transparent, the 
projected image through an OHP projector was bright and clear. 
REFERENTIAL EXAMPLE 1 
Positive Type Light-Sensitive Heat-Sensitive Recording Material Containing 
a High Boiling Point Solvent 
A sample was prepared by repeating the process of Example 1 except that the 
coating solution (1-4-e) containing a high boiling point solvent for use 
in light-sensitive heat-sensitive layer (3) was used instead of the 
coating solution (1-4-c). 
When the thus prepared recording material was subjected to exposure and 
then heated at 120.degree. C. for 5 seconds using a hot plate in the same 
manner as in Example 1, a foul smell similar to that of 
trimethylolpropanetrimethacrylate was detected. In addition, the projected 
image through an OHP projector was dark. 
EXAMPLE 2 
Negative Type Light-Sensitive Heat-Sensitive Recording Material 
The coating solution for use in light-sensitive heat-sensitive layer (4) 
obtained in 1-4-d above was coated on the surface of a polyethylene 
terephthalate film having a thickness of 100 .mu.m using a coating bar, in 
such an amount that the dry weight of the resulting layer was 8 g/m.sup.2 
and the coated solution was dried at 30.degree. C. for 10 minutes. The 
surface of the thus coated light-sensitive heat-sensitive layer was 
further coated with the coating solution for use in protective layer (1) 
obtained in 1-6-a above using a coating bar in such an amount that the dry 
weight of the resulting protective layer was 5 g/m.sup.2 and then dried at 
30.degree. C. for 10 minutes. In this way, the sample of Example 2 was 
obtained. 
Through a lith film on which an black-and-white image had been developed, 
the thus prepared light-sensitive heat-sensitive recording material was 
exposed to ultraviolet light using a 1,000 W high pressure mercury lamp 
(Jet Light, manufactured by Oak & Co., Ltd.). When the UV-exposed 
recording material was heated at 110.degree. C. for 5 seconds using a hot 
plate, a clear magenta-colored negative image was obtained. The density of 
magenta in the non-image area was found to be 1.3. 
EXAMPLES 3 TO 6 AND REFERENTIAL EXAMPLE 2 
A series of suspensions of capsules were prepared basically repeating the 
procedure of Example 1 for the preparation of the capsules in which the 
electron donating colorless dye (1) obtained in 1-1-a above was 
incorporated. That is, a series of suspensions of capsules having a mean 
particle size of 0.5 .mu.m in which the electron donating colorless dye 
(1) was incorporated were prepared by repeating the process of 1-1-a 
except that 10.4 g of ethyl acetate used in 1-1-a was replaced by the same 
amount of a solvent or a mixture of solvents as shown in Table 1 below. 
Coating solutions for use in light-sensitive heat-sensitive layers were 
prepared using the thus obtained capsules in the same manner as in Example 
1 and coated on the surface of a polyethylene terephthalate film having a 
thickness of 100 .mu.m using a coating bar, in such an amount that the dry 
weight of the resulting layer was 8 g/m.sup.2 and the coated solution was 
dried at 30.degree. C. for 10 minutes. 
The surface of the thus coated light-sensitive heat-sensitive layer was 
further coated with the coating solution for use in protective layer (1) 
obtained in 1-6-a above using a coating bar in such an amount that the dry 
weight of the resulting protective layer was 2 g/m.sup.2 and then dried at 
30.degree. C. for 10 minutes. In this way, samples of Examples 3 to 6 and 
Referential Example 2 were obtained. 
Through a lith film on which an image had been developed and though an 
optical filter which cut out light of 410 nm or below (SC-41 filter, 
manufactured by Fuji Photo Film Co., Ltd.), the thus prepared 
light-sensitive heat-sensitive recording materials were exposed to 
ultraviolet light using a 1,000 W high pressure mercury lamp (Jet Light, 
manufactured by Oak & Co., Ltd.). Thereafter, the UV-exposed recording 
materials were heated at 120.degree. C. for 5 seconds using a hot plate. 
The results obtained are shown in Table 1. 
TABLE 1 
______________________________________ 
Odor at Results of 
Time of Heat 
Projection 
Solvent Development Using OHP 
______________________________________ 
Example 3 
Methylene Chloride 
No Bright 
Example 4 
Isopropyl Acetate 
No Bright 
Example 5 
Methyl Propionate 
No Bright 
Example 6 
1/1 Mixture of 
No Bright 
Methylene Chloride 
and Ethyl Acetate 
Referential 
Tricresyl Yes, though Slightly 
Example 2 
Phosphate weak dark 
______________________________________ 
The chemical structures of compounds used in the preparation of coating 
solutions above are shown below. 
##STR1## 
EXAMPLES 7 TO 10 AND REFERENTIAL EXAMPLES 3 AND 4 
Preparation of Coating Solution 
2-1 Preparation of capsules including electron donating colorless dye (1) 
To 12.4 g of the above electron donating colorless dye (3) dissolved in 
10.4 g of ethyl acetate were added 27 g of Takenate D-110N (manufactured 
by Takeda Chemical Industries Ltd.) and 3 g of Millionate MR200 
(manufactured by Nippon Polyurethane Industry Co., Ltd.). The resulting 
solution was added to a mixture of 4.6 g of polyvinyl alcohol and 74 g of 
water and then subjected to emulsification and dispersion at 20.degree. C. 
to obtain an emulsion. The thus obtained emulsion was mixed with 100 g of 
water and heated at 60.degree. C. with stirring. After 2 hours of heating, 
a suspension of capsules in which the electron donating colorless dye (3) 
was incorporated as a core material was obtained, with a mean particle 
size of 0.5 .mu.m. 
2-2 Preparation of emulsion of photo-hardenable composition 
2-2-a Emulsion of photo-hardenable composition (5) 
In 3 g of ethyl acetate were dissolved 0.1 g of the above 
photopolymerization initiator (1), 0.05 g of the above spectral 
sensitization dye (1) and 0.2 g of N-phenylglycine ethyl ester as an 
auxiliary agent to enhance polymerization. To this was then added 8 g of 
the above polymerizable electron accepting compound (1). The resulting 
solution was added to a mixed solution of 9.6 g of a 7.5% aqueous solution 
of PVA, 0.8 g of a 2% aqueous solution of the above surface active agent 
(1) and 0.8 g of a 2% aqueous solution of another surface active agent 
(5). Thereafter, the resulting mixture was emulsified using a homogenizer 
(manufactured by Nippon Seiki Co., Ltd.) at 10,000 rpm for 5 minutes to 
obtain an emulsion of photo-hardenable composition (5). 
2-2-b Emulsion of photo-hardenable composition (6) 
In 4 g of ethyl acetate were dissolved 0.2 g of the above 
photopolymerization initiator (1), 0.2 g of the above spectral 
sensitization dye (1) and 0.2 g of N-phenylglycine ethyl ester as an 
auxiliary agent to enhance polymerization. To this were added 10 g of 
(1-methyl-2-phenoxy)ethyl resorcinate as an electron accepting compound 
and 8 g of trimethylolpropanetriacrylate monomer. The resulting solution 
was added to a mixed solution of 19.2 g of a 15% aqueous solution of poly 
vinyl alcohol (PVA), 4.8 g of water, 0.8 g of a 2% aqueous solution of the 
aforementioned surface active agent (1) and 0.8 g of a 2% aqueous solution 
of surface active agent (5). The resulting mixture was emulsified using a 
homogenizer (manufactured by Nippon Seiki Co., Ltd.) at 10,000 rpm for 5 
minutes to obtain an emulsion of photo-hardenable composition (6). 
2-3 Preparation of coating solution for use in positive type 
light-sensitive heat-sensitive layer 
A coating solution for use in a positive type light-sensitive 
heat-sensitive layer (5) was prepared by mixing 4 g of the capsules (2-1) 
which included electron donating colorless dye (1) with 12 g of the 
emulsion (2-2-a) of photo-hardenable composition (5) and 12 g of 15% 
aqueous solution of PVA. 
2-4 Preparation of coating solution for use in negative type 
light-sensitive heat-sensitive layer 
A coating solution for use in negative type light-sensitive heat-sensitive 
layer (6) was prepared by mixing 1 g of the capsules (2-1) which included 
the electron donating colorless dye (1) with 10 g of the emulsion (2-2-b) 
of the photo-hardenable composition (6). 
2-5 Preparation of coating solution for use in protective layer 
A coating solution for use in protective layer (3) was prepared by mixing 
4.5 g of a 10% aqueous solution of gelatin with 1.5 g of distilled water, 
0.5 g of a 2% aqueous solution of surface active agent (3), a 1.5 g of a 
1% aqueous solution of sodium 2,4-dichloro-6-hydroxy-s-triazine, a 
predetermined amount of Cycolloid 72 (manufactured by Fuji-Devison 
Chemical Ltd.) and 1 g of Snowtex N. Cycolloid 72 was used in such an 
amount that the coating amount was 50 mg/m.sup.2. 
The structure of surface active agent (5) used in the above coating 
solutions is shown below. 
Surface Active Agent (5) 
EQU C.sub.12 H.sub.25 SO.sub.3 Na 
Preparation and evaluation of light-sensitive heat-sensitive recording 
material 
EXAMPLE 7 
Positive Type Light-Sensitive Heat-Sensitive Recording Material 
The coating solution for use in light-sensitive heat-sensitive layer (5) 
obtained in 2-3 above was coated on the surface of a polyethylene 
terephthalate film having a thickness of 100 .mu.m using a coating bar, in 
such an amount that the dry weight of the resulting layer was 8 g/m.sup.2 
and the coated solution was dried at 30.degree. C. for 10 minutes. The 
surface of the thus coated light-sensitive heat-sensitive layer was 
further coated with the coating solution for use in the protective layer 
(3) obtained in 2-5 above using a coating bar in such an amount that the 
dry weight of the resulting protective layer was 2 g/m.sup.2 and then 
dried at 30.degree. C. for 10 minutes. In this way, the sample of Example 
7 was obtained. 
Through a lith film on which an image for cyan had been developed and an 
optical filter which cut out light of 410 nm or below (SC-41 filter, 
manufactured by Fuji Photo Film Co., Ltd.), the thus prepared 
light-sensitive heat-sensitive recording material was exposed to 
ultraviolet light using a 1,000 W high pressure mercury lamp (Jet Light, 
manufactured by Oak & Co., Ltd.). When the UV-exposed recording material 
was heated at 110.degree. C. for 5 seconds using a hot plate, a clear 
cyan-color image was obtained with a high resolution power and no turbid. 
EXAMPLE 8 
Negative Type Light-Sensitive Heat-Sensitive Recording Material 
The coating solution for use in light-sensitive heat-sensitive layer (6) 
obtained in 2-4 above was coated on the surface of a polyethylene 
terephthalate film having a thickness of 100 .mu.m using a coating bar, in 
such an amount that the dry weight of the resulting layer was 8 g/m.sup.2 
and the coated solution was dried at 30.degree. C. for 10 minutes. The 
surface of the thus coated light-sensitive heat-sensitive layer was 
further coated with coating solution for use in protective layer (3) 
obtained above using a coating bar in such an amount that the dry weight 
of the resulting protective layer was 5 g/m.sup.2 and then dried at 
30.degree. C. for 10 minutes. In this way, a negative type light-sensitive 
heat-sensitive recording material was obtained. 
Through a lith film on which an black-and-white image had been developed, 
the thus prepared light-sensitive heat-sensitive recording material was 
exposed to ultraviolet light using a 1,000 W high pressure mercury lamp 
(Jet Light, manufactured by Oak & Co., Ltd.). When the UV-exposed 
recording material was heated at 110.degree. C. for 5 seconds using a hot 
plate, a clear cyan-colored negative image was obtained with a high 
resolution power and no turbid. 
EXAMPLES 9 AND 10 AND REFERENTIAL EXAMPLES 3 AND 4 
A series of microcapsule suspensions with varying particle sizes were 
prepared by basically repeating the procedure described in section 2-1 
above "Preparation of capsules including electron donating achromatic 
dye". 
More specifically, a series of microcapsule suspensions having different 
particle sizes as shown in Table 2 below were prepared by changing the 
emulsification conditions at the time of microcapsule preparation. 
Light-sensitive heat-sensitive recording materials were obtained from the 
thus prepared microcapsule suspensions and subjected to exposure and image 
development in the same manner as in Example 7. The Results of the 
evaluation are shown in Table 2 below. 
TABLE 2 
______________________________________ 
Mean Particle 
Size of Resolution Clearness 
Microcapsules 
of Image of Image 
______________________________________ 
Example 9 
0.9 .mu.m Almost good Almost good 
Example 10 
1.5 .mu.m Almost good Almost good 
Referential 
2.5 .mu.m Little bad Little 
Example 3 turbid 
Referential 
6 .mu.m Markedly bad 
Wholly turbid, 
Example 4 rough surface 
______________________________________ 
EXAMPLES 11 TO 14 AND REFERENTIAL EXAMPLE 5 
Positive Type Light-Sensitive Heat-Sensitive Recording Material 
Light-sensitive heat-sensitive recording materials were prepared using the 
following supports A to E. 
1. Support A: 
Wood pulp consisting of 20 parts LBSP and 80 parts LBKP was beaten to a 
Canadian freeness of 300 cm.sup.3 using a disc refiner. To this were added 
1.0 part of sodium stearate, 0.5 part of an anionic polyacrylamide, 1.5 
parts of aluminium sulfate and 0.5 part of polyamide polyamine 
epichlorohydrin on the basis of dry weight of the wood pulp. The resulting 
mixture was then made into paper having a basis weight of 80 g/m.sup.2 
using a Fourdrinier paper machine. The density was set to 1.0 g/cm.sup.3 
using a machine calender. 
After subjecting the resulting paper to corona discharge the paper was 
laminated with a polyethylene resin layer having a thickness of 20 .mu.m, 
by coating one side of the paper with a low density polyethylene (MI=7 
g/10 min; density=0,923 g/cm.sup.3) containing 10% by weight of titanium 
oxide using an extrusion coating. Thereafter, the other side of the paper 
(backside) was subjected to corona discharge and then laminated with a 
polyethylene resin layer having a thickness of 20 .mu.m, by coating the 
backside with a high density polyethylene (MI=8 g/10 min; density=0.950 
g/cm.sup.3) using extrusion coating. In this way, a paper support with 
both sides laminated with polyethylene layers was obtained. 
2. Support B: 
Lumilar E-60 (100 .mu.m in thickness) manufactured by Toray Industries, 
Inc. (A polyester film filled with a white pigment) 
3. Support C: 
Lumilar E-20 (38 .mu.m in thickness) manufactured by Toray Industries, Inc. 
(A polyester film filled with a white pigment) 
4. Support D: 
Merinex 990 (184 .mu.m in thickness) manufactured by ICI (A polyester film 
filled with a white pigment (barium sulfate)) 
5. Support E: 
Yupo FPG (110 .mu.m in thickness) manufactured by Oji Paper Co., Ltd. (A 
polyester film filled with a white pigment) 
Onto the front surface of Support A, a gelatin solution was coated with a 
coating bar to provide a flatting surface layer. The dry film thickness of 
the flatting surface layer was controlled to 0.3 .mu.m (Example 11), 0.5 
.mu.m (Example 12), 1 .mu.m (Example 13) or 2 .mu.m (Example 14) by 
adjusting the concentration of the gelatin solution and the coating bar. 
In Comparative Example 5, the support was not provided with any flatting 
surface layer. 
The coating solution obtained in section 1-4-a above for use in the 
light-sensitive heat-sensitive layer (1) was coated on the surface of 
Support A using a coating bar, in such an amount that the dry weight of 
the resulting layer was 8 g/m.sup.2 and the coated solution was dried at 
30.degree. C. for 10 minutes. The surface of the thus coated layer was 
further coated with the coating solution for use in the intermediate layer 
(1) obtained in 1-5-a above in such an amount that the dry weight of the 
resulting intermediate layer was 2 g/m.sup.2 and then dried. The surface 
of the thus coated first intermediate layer was further coated with 
coating solution for use in light-sensitive heat-sensitive layer (2) 
obtained 1-4-b above in such an amount that the dry weight of the 
resulting light-sensitive heat-sensitive layer was 8 g/m.sup.2 and then 
dried. The surface of the thus coated light-sensitive heat-sensitive layer 
was further coated with coating solution for use in intermediate layer (2) 
obtained in 1-5-b above in such an amount that the dry weight of the 
resulting second intermediate layer was 2 g/m.sup.2 and then dried. The 
surface of the thus coated second intermediate layer was further coated 
with coating solution for use in light-sensitive heat-sensitive layer (3) 
obtained in 1-4-c above in such an amount that the dry weight of the 
resulting light-sensitive heat-sensitive layer was 8 g/m.sup.2 and then 
dried. Finally, the surface of the thus coated light-sensitive 
heat-sensitive layer was further coated with coating solution for use in 
the protective layer (1) obtained in 1-6-a above using a coating bar in 
such an amount that the dry weight of the resulting protective layer was 2 
g/m.sup.2 when dried at 30.degree. C. for 10 minutes. In this way, samples 
of this invention and Referential Examples were obtained. 
Through a lith film on which an image for yellow had been developed and an 
optical filter which cut out light of 410 nm or below (SC-41 filter, 
manufactured by Fuji Photo Film Co., Ltd.), the thus prepared 
light-sensitive heat-sensitive recording material was exposed to 
ultraviolet light using a 2,000 W high frequency lighting type ultra-high 
pressure mercury lamp (Printer P627GA, manufactured by Dainippon Screen 
Co., Ltd.). The thus treated recording material was then exposed to light 
of the mercury lamp through a lith film on which an image for magenta had 
been developed and through an interference filter which transmits only 
light of a wavelength of 365 to 400 nm. The resulting recording material 
was further exposed to light of the mercury lamp through a lith film on 
which an image for cyan use had been developed and through an interference 
filter which transmits only light of a wavelength of 340 to 365 nm. A 
latent image was obtained in this way. Thereafter, the UV-exposed 
recording material was heated at 120.degree. C. for 5 seconds using a hot 
plate. 
In this instance, heat development was carried out 10 minutes after 
exposure, resolution, density evenness and degree of fogging in terms of 
OD (yellow density measured using a reflection density meter, RD 91, 
manufactured by MACBETH) of the resulting images was evaluated with the 
results shown in Table 3 below. 
TABLE 3 
______________________________________ 
Results of Evaluation 
Thickness 
of Flatting 
Surface Reso- Density 
Fogging 
Support Layer (.mu.m) 
lution Evenness 
OD 
______________________________________ 
Example 11 
A 0.3 slightly 
slightly 
good 
good good 0.23 
Example 12 
A 0.5 good good good 
0.15 
Example 13 
A 1 very very good 
good good 0.13 
Example 14 
A 2 very very good 
good good 0.14 
Referential 
A 0 bad bad bad 
Example 5 0.30 
______________________________________ 
EXAMPLES 15 TO 18 AND REFERENTIAL EXAMPLES 6 AND 7 
Negative Type Light-Sensitive Heat-Sensitive Recording Material 
The coating solution obtained in section 1-4-d above for use in 
light-sensitive heat-sensitive layer (4) was coated on the surface of each 
of the supports shown below in Table 4 using a coating bar, in such an 
amount that the dry weight of the resulting layer was 8 g/m.sup.2 and the 
coated solution was dried at 30.degree. C. for 10 minutes. The surface of 
the thus coated light-sensitive heat-sensitive layer was further coated 
with coating solution for use in protective layer (1) obtained in 1-6-a 
above using a coating bar in such an amount that the dry weight of the 
resulting protective layer was 5 g/m.sup.2 and then dried at 30.degree. C. 
for 10 minutes. In this way, samples of the invention and Referential 
Examples were obtained. 
Through a lith film on which a black-and-white image had been developed, 
the thus prepared light-sensitive heat-sensitive recording material was 
exposed to ultraviolet light using a 1,000 W high pressure mercury lamp 
(jet Light, manufactured by Oak & Co., Ltd.). After subjecting to 
exposure, evaluation was carried out in the same manner as in Example 11, 
with the results shown in Table 4 being obtained. 
TABLE 4 
______________________________________ 
Results of Evaluation 
Thickness 
of Flatting 
Surface Reso- Density 
Fogging 
Support Layer (.mu.m) 
lution Evenness 
OD 
______________________________________ 
Example 15 
A 0.3 slightly 
slightly 
good 
good good 0.23 
Example 16 
A 0.5 good good good 
0.15 
Example 17 
A 1 very very good 
good good 0.13 
Example 18 
A 2 very very good 
good good 0.14 
Referential 
A 0 bad bad bad 
Example 6 0.30 
______________________________________ 
EXAMPLE 19 
The coating solution obtained in section 1-4-a above for use in the 
light-sensitive heat-sensitive layer (1) was coated on the surface of 
Support A obtained in Examples 11 to 14 using a coating bar, in such an 
amount that the dry weight of the resulting layer was 8 g/m.sup.2 and the 
coated solution was dried at 30.degree. C. for 10 minutes. The surface of 
the thus coated layer was further coated with coating solution for use in 
intermediate layer (1) obtained in section 1-5-a above in such an amount 
that the dry weight of the resulting intermediate layer was 2 g/m.sup.2 
and then dried. The surface of the thus coated first intermediate layer 
was further coated with coating solution for use in the light-sensitive 
heat-sensitive layer (2) obtained in section 1-4-b above in such an amount 
that the dry weight of the resulting light-sensitive heat-sensitive layer 
was 8 g/m.sup.2 and then dried. The surface of the thus coated 
light-sensitive heat-sensitive layer was further coated with coating 
solution for use in the intermediate layer (2) obtained in section 1-5-b 
above in such an amount that the dry weight of the resulting second 
intermediate layer was 2 g/m.sup.2 and then dried. The surface of the thus 
coated second intermediate layer was further coated with coating solution 
for use in the light-sensitive heat-sensitive layer (3) obtained in 
section 1-4-c above in such an amount that the dry weight of the resulting 
light-sensitive heat-sensitive layer was 8 g/m.sup.2 and then dried. 
Finally, the surface of the thus coated light-sensitive heat-sensitive 
layer was further coated with coating solution for use in the protective 
layer (1) obtained in section 1-6-a above using a coating bar in such an 
amount that the dry weight of the resulting protective layer was 2 
g/m.sup.2 and then dried at 30.degree. C. for 10 minutes. In this way, 
samples of Example 19 was obtained. 
Through a lith film on which an image for yellow had been developed and an 
optical filter which cut out light of 410 nm or below (SC-41 filter, 
manufactured by Fuji Photo Film Co., Ltd.), the thus prepared 
light-sensitive heat-sensitive recording material was exposed to 
ultraviolet light using a 2,000 W high frequency lighting type ultra-high 
pressure mercury lamp (Printer P627GA, manufactured by Dainippon Screen 
Co., Ltd.). The thus treated recording material was then exposed to light 
of the mercury lamp through a lith film on which an image for magenta had 
been developed and through an interference filter which transmits only 
light of a wavelength of 365 to 400 nm. The resulting recording material 
was further exposed to light of the mercury lamp through a lith film on 
which an image for cyan had been developed and through an interference 
filter which transmits only light of a wavelength of 340 to 365 nm. A 
latent image was obtained in this way. Thereafter, the UV-exposed 
recording material was heated at 120.degree. C. for 5 seconds using a hot 
plate. As a result, a clear full-color positive image where the OD value 
(reflection density) of each color was about 2.0 was obtained. Any 
unevenness of density of image or repellence or flocculation of the 
coating solutions were not observed on the surface of the recording 
material. 
EXAMPLE 20 
Coating solution prepared in the same manner as in section 1-4-d above 
except that capsules which included the electron donating colorless dye 
(1) was replaced by capsules which included the electron donating 
colorless dye (3) obtained in section 1-1-c, was coated on the surface of 
a support using a coating bar, in such an amount that the dry weight of 
the resulting layer was 8 g/m.sup.2 and then dried at 30.degree. C. for 10 
minutes. The surface of the thus coated layer was coated with coating 
solution for use in intermediate layer (1) obtained in section 1-5-a above 
using a coating bar in such an amount that the dry weight of the resulting 
layer was 5 g/m.sup.2 and then dried at 30.degree. C. for 10 minutes. In 
this way, a sample of Example 20 was obtained. 
Through a lith film on which a back-and-white image had been developed, the 
thus prepared light-sensitive heat-sensitive recording material was 
exposed to ultraviolet light using 2,000 W high pressure mercury lamp (jet 
light, manufactured by ORC Co., Ltd.). Thereafter, the exposed recording 
material was heated at 120.degree. C. for 5 seconds using a hot plate. As 
a result, a clear negative monocolor (cyan) image was obtained. 
EXAMPLES 21 AND 22 
Capsules were prepared in the same manner as in section 1-1-a except that 
the 8% aqueous solution of phthalate modified gelatin was replaced by an 
8% aqueous solution of acetylate modified gelatin (Example 21) or an 8% 
aqueous solution of succinate modified gelatin (Example 22). As a result, 
stable suspensions of capsules were obtained as in section 1-1-a and any 
residues were not observed when they were filtrated. 
Further, the same procedures were repeated except that the electron 
donating colorless dye (1) was replaced by the above-mentioned electron 
donating colorless dye (2) or (3). As a result, similar good results were 
obtained. 
REFERENTIAL EXAMPLE 7 
The procedure of section 1-1-a was repeated except that the 8% aqueous 
solution of phthalate modified gelatin was replaced by an 8% aqueous 
solution of unmodified gelatin. As a result, flocculation occurred within 
few minutes from the beginning of emulsification and dispersion and 
thereby the following capsulation reaction could not be carried out any 
more and the resulting mixture could not be filtrated at all. 
Further, the same procedures were repeated except that the electron 
donating colorless dye (1) was replaced by the above-mentioned electron 
donating colorless dye (2) or (3). As a result, similar results occurred. 
Since high boiling point solvents which are usually used at the time of the 
prior art microcapsule formation process are not used in the recording 
material of the present invention, evaporation of toxic solvents does not 
occur when the inventive recording material of the present invention is 
subjected to heat development. Also, by the use of the recording material 
of the present invention, formation of haze can be reduced to such a low 
level that the material can be used in projection type applications such 
as OHP, slide and the like. For example, when images developed on the 
recording material of the invention were projected on a screen using an 
OHP, the projected images were quite bright showing no scattering of 
light. 
In addition, with using microcapsules having markedly small particle sizes, 
small picture elements can be obtained thereby rendering possible 
formation of high resolution images. Also, as a result of the reduction of 
the particle size of microcapsules, scattering in light inside the 
recording layers can be repressed and therefore clear images can be 
obtained. 
Moreover, according to the present invention, a recording material which 
does not show reduced resolving power and uneven image density, which 
usually occurs by uneven support surface, can be provided. Such an effect 
was attained by the use of a polyester support in which a white pigment 
was filled. Because of this, a clear high visibility image can be obtained 
by the use of the recording material of the present invention. 
Still further, microcapsules having markedly small particle size can be 
obtained in the method of the present invention without occurrence of 
flocculation. Also, a light-sensitive heat-sensitive recording material 
which gives a clear image without uneven image density can be obtained by 
using microcapsules prepared in the method of the present invention. 
While the invention has been described in detail and with reference to 
specific embodiments thereof, it will be apparent to one skilled in the 
art that various changes and modifications can be made therein without 
departing from the spirit and scope thereof.