Photo and pressure sensitive recording media comprising an adhesive agent

A photo and pressure sensitive recording medium comprising a base sheet, supporting thereon a color developing agent which reacts with a dye precursor to develop color and an adhesive substance with which the recording medium may be adhered to any suitable material or body. The color developing agent may be coated on one surface of the base sheet and adhesive is applied on the other surface of the base sheet. The adhesive substance may be of thermoplastic type or enveloped in microcapsules crushable under pressure. A peel-off sheet may be conted on the adhesive substance. Alternatively, the color developing agent and the adhesive substance may both be supported on one surface of the base sheet, as well as photo-curable microcapsules containing the dye precursor. The adhesive substance may also be enveloped in microcapsules which are ruptured under pressure to flow out the contained adhesive, with which the recording medium is bonded to a general-purpose sheet such as ordinary paper to provide a one-body recorded sheet.

BACKGROUND OF THE INVENTION 
This invention relates to a photo and pressure sensitive recording medium 
adapted for reproduction or recording of an image. 
There has been proposed a photo and pressure sensitive medium capable of 
recording an image, which comprises a base sheet and a layer formed 
thereon including combination of microcapsules each containing a dye 
precursor and a photo-curable resin, and a color developing agent 
reactable with the dye precursor to develop color. When the recording 
sheet is exposed to light, the microcapsules existing on a particular area 
exposed to the light are cured. The remaining uncured microcapsules are 
ruptured by applying pressure thereto to flow out the dye precursor 
contained therein, which will then react with the color developing agent 
to reproduce a given photo-image on the recording sheet. Such conventional 
recording sheet of so-called self-development type is shown in the U.S. 
Pat. No. 4,440,846, for example. 
Another type of the photo and pressure sensitive recording sheet has also 
been known, that is of a transfer type. The recording sheet of a transfer 
type consists of two separate sheets, one coated with the microcapsules 
each containing the dye precursor and the photo-curable resin and the 
other with the color developing agent. The microcapsule sheet is exposed 
to light to produce thereon a latent image, which is developed to a photo 
image on the developer sheet by bringing the latter sheet into close 
contact with the former sheet, by way of pressure rollers. Such 
conventional recording sheet is disclosed in the U.S. Pat. No. 4,399,209, 
for example. 
Using such photo and pressure sensitive recording sheet of self development 
type or transfer type as a copy paper in copying machines, thus providing 
a clear reproduced image with definite contour, as in electrophotographic 
reproduction. According to the prior art technique, however, it is not 
possible to develop photo-images on general-purpose material such as 
ordinary paper, film, panel or cloth. 
SUMMARY OF THE INVENTION 
It is therefore an object of this invention to provide a novel photo and 
pressure sensitive recording medium which can be used not only as a copy 
paper but also to form photo-images on any desired material. 
Another object of this invention is to provide an adhesive sheet or tape on 
which a photo-image is developed. 
According to one aspect of this invention, there is provided a photo and 
pressure sensitive recording medium comprising a sheet shaped supporting 
member, a first component which reacts with a second component to develop 
color, and an adhesive substance, said first component and said adhesive 
substance being supported on the sheet shaped supporting member. 
According to a modification of this invention, there is provided a photo 
and pressure sensitive recording medium comprising a sheet shaped 
supporting member; a first layer formed on one surface of the supporting 
member and including a first component of a developing agent reactable 
with a second component of the developing agent to develop color; and a 
second layer formed on the other surface of the supporting member and 
including adhesive agent. 
According to another modification of this invention, there is provided a 
photo and pressure sensitive recording medium comprising a sheet shaped 
member supporting thereon a first component of a developing agent, first 
microcapsules each enveloping therein a second component reactable with 
the second component to develop color and a third component which 
increases the mechanical strength of the first microcapsules when 
irradiated with light, second microcapsules each enveloping therein 
adhesive agent. 
The recording medium of this invention may be adhered to a separate sheet, 
which may be a general-purpose product such as ordinary paper, through the 
adhesive agent on the surface of the recording medium. 
With the first modification, the first component of the developing agent 
reacts with the second component contained in microcapsules which are 
dispersed in the first layer or supported on a separate recording sheet. 
Only portions of the microcapsules exposed to light increases their 
mechanical strength against rupture. As a consequence, when the recording 
medium or the separate recording sheet which has been exposed to light is 
passed between pressure applying rollers, only the microcapsules not 
exposed to light are ruptured so that the second component therein flows 
out. The second component thus flown out reacts with the first component 
in the first layer of the recording medium to develop a color image 
corresponding to a manuscript. The recording medium on which the color 
image has been produced is adhered to any desired material through the 
second adhesive layer. The second adhesive layer may be coated with a 
silicon-coated peel-off sheet. 
With the second modification, after exposing to light, the recording medium 
is passed between pressure applying rollers, whereby a portion of the 
first microcapsules not exposed to light are ruptured so that the second 
component therein flows out to react with the first component and, at the 
same time, the second microcapsules are all ruptured so that the adhesive 
agent flows out. Thus, the recording medium is adhered to a separate sheet 
adapted to pass between the pressure applying rollers together with the 
recording medium. The photo-image produced on the recording medium is 
visible through the sheet shaped member and/or the separate sheet, at 
least one of which is made of a transparent material.

DESCRIPTION OF THE PREFERRED EMBODIMENTS 
As shown in FIG. 1, one example of an image adhesion sheet 10 embodying the 
invention comprises a base sheet 1, a first layer 2 coated on one surface 
of the base sheet 1 and the second layer 3 coated on the other surface of 
the base sheet 1. The sheet 10 should preferably be prepared as thin as 
possible. 
The base sheet 1 may be of any suitable material, such as paper or 
cellulose; synthetic paper; polyester, polycarbonate, polyethylene, 
polyethil methacrylate, polystyrene, polyamide or other resin film; or 
wooven material such as nylon, silk and cotton. 
The first layer 2 may comprises a combination of microcapsules each 
containing a dye precursor and a photo-curable resin, and a color 
developing agent reactable with the dye precursor to develop color, in 
which case the recording media of a self-development type is provided. The 
first layer 2 may alternatively comprise the color developing agent, not 
containing the microcapsules, which is applicable to the recording medium 
of a transfer type. The color developing agent is determined in relation 
to a specific composition selected as the dye precursor, and may be in 
general acid material including silicate such as acid white clay, active 
clay, kaolin zoolite and bentonite, inorganic acid such as zinc oxide and 
titanium oxide; phenol-based compound such as P-creosol, P-phenylphenol, 
P-chlorophenol, 2,2 methylenebis (4-tert-buthylphenol) and phenol 
formaldehyde condensate; aromatic carboxylic compound such as salycylic 
acid, hallic acid and P-buthyl benzoic acid; metal chloride of aromatic 
carboxylic compound such as zinc salicylate and tin selicylate; metal 
compound such as ferric stearate, magnesium stearate and zinc stearate; 
phonolnovolac resin; and organic acid. These compounds may be used alone 
or in combination. 
The second layer 3 comprises an adhesive agent which may be classified into 
a pressure sensitive type and a thermal sensitive type. The former type 
adhesive may include a microcapsule adapted to be ruptured when 
pressurized and enveloping therein a liquid adhesive agent. The liquid 
adhesive agent may be a natural one such as casein and starch paste; 
thermoplastic resin such as polyvinyl acetate, copolymer of vinyl acetate 
and ethylene, acrylate resin and copolymer of vinyl acetate and acrylate; 
thermosetting resin such as urea resin, melamine resin, phenol resin, 
epoxy resin and urethane resin; and elastomer type adhesive such as 
natural rubber, nitrile rubber and chloroprene rubber. Such materials may 
be dissolved in a solvent to prepare the liquid adhesive agent. The liquid 
adhesive agent thus prepared is enveloped in the microcapsules made of 
gelatin, for example. A binder, filler, wax or viscosity adjusting agent 
or the like may be contained in the microcapsules, and the resulting 
microcapsules are dispersed on the surface opposite to the first layer 2. 
The binder may preferably be gelatine, casein or 
carboxymethylcollulosepolyacryl acid. 
The adhesive agent of another, thermal sensitive type may be thermoplastic 
resin as described before, and is dispersed or dissolved in a suitable 
solvent. The resulting liquid adhesive is applied to the base sheet 1 with 
a blade coater. Otherwise, the thermoplastic resin may be directly applied 
with a hot-melt coater. 
The microcapsules contained in the first layer 2 of the image adhesion 
sheet 10 of a self development type, are in general made of a spherical 
outer shell of gelatin, polyamide, polyvinyl alcohol, polyisocyanate resin 
or other soft and collapsible material, encapsulating dye precursor of 
trymethane or spiropyran-based dye and photosetting resing of a compound 
of acrloyl group such as trimethylelpropanetriacrylate, as well as a 
photopolymerization initiator of benzofenon or benzoyl alkyl ether or the 
like. 
The image adhesion sheet 10 shown in FIG. 1 is adhered to a separate sheet 
material 4 in a manner shown in FIG. 2 in which the adhesive agent used in 
the layer 3 is of thermosensitive type or shown in FIG. 3 in which the 
adhesive agent of pressure sensitive type is used. In these drawings, the 
first layer 2 contains only chromogenic material but microcapsules, 
meaning that the sheet 1 is used as a recording media of a transfer type. 
As shown in FIG. 2, a given photo-image has already been developed on the 
image adhesion sheet 10a by reacting the color developing agent contained 
in the first layer 2 and a corresponding dye precursor contained in 
microcapsules on a separate recording media sheet, not shown, in a known 
manner. After that, the image adhesion sheet 10a is caused to pass between 
a pair of heat rollers 5a and 5b, together with the sheet material 4 which 
is separately delivered to come into close contact with the adhesive layer 
3 of the image adhesion sheet 10a. Thus, the thermoplastic adhesive in the 
layer 3 melts under heat transmitted from the heat rollers 5a and 5b so 
that the juxtaposed sheet material 4 is adhered to the image adhesion 
sheet 10a. The sheet material 4 thus looks as if the photoimage was 
actually printed or developed thereon. 
When the image adhesion sheet 10b employs the adhesive of pressure 
sensitive type enveloped in microcapsules, as shown in FIG. 3, the sheet 
material 4 may be adhered to the image adhesion sheet 10b at the same time 
with the developing process. More particularly, the developing process 
includes a step of passing the developing sheet between a pair of pressure 
applying rollers 8a and 8b, together with a microcapsule sheet 6, which 
has been exposed to light to produce on a surface 7 thereof a latent image 
corresponding to a manuscript. The microcapsules in an area not exposed to 
light are thus ruptured to flow out the inside dye precursor, which is 
transferred to the surface of the developing sheet and reacts with the 
color developing agent in the layer 2 to develop thereon the latent image. 
When the developing sheet is the mere image adhesion sheet 10b, a separate 
sheet or card 4 is also introduced between the pressure applying roller 
pair 8a and 8b on the side of the adhesive layer 3 is ruptured under 
pressure applied by the rollers 8a and 8b to flow out the adhesive agent. 
whereby the sheet or card 4 is effectively bonded to the image adhesion 
sheet 10b. This is a preferred embodiment because no special means is 
required for adhesion of the sheet 4. 
If the image adhesion sheet 10 is prepared as of self-developing type, it 
will easily be understood that a similar process may also be applied as in 
the case shown in FIG. 2 or FIG. 3. 
FIG. 4 shows an image adhesion sheet in accordance with another embodiment 
of this invention. More particularly, the image adhesion sheet 20 
comprises a base sheet 11, a first layer 12 formed on one surface of the 
base sheet 11, a second layer 13 formed on the other surface of the base 
sheet 11 and a silicon-coated peel-off sheet 14 adhered to the second 
layer 13. Since the base sheet 11 and the first layer 12 are similar to 
those of the image adhesion sheet 10 shown in FIG. 1, no further 
description is given here. The adhesive layer 13 contains any suitable 
adhesive agent which may be of acryl type, silicon type, natural rubber 
type, synthetic rubber type, vinyl type, or the like. 
One example of the image adhesion sheet shown in FIG. 4 is given hereunder. 
The composition of the adhesive agent of the layer 13 and the color 
developing agent in the layer 12 are as follows: 
______________________________________ 
(parts) 
______________________________________ 
Adhesive Agent 
Natural rubber (Mooney viscosity of 41) 
50 
SBR 1502 50 
Rosin ester 60 
Color Developing Agent 
P-phenylphenol 50 
Phenolnovolac 50 
Pholyvinyalcohol 10 
______________________________________ 
The adhesive agent having the above composition was dissolved in toluene to 
have its solid content of 20% and the resultant was applied to a base 
sheet 11 made of 25 .mu.m-thick polyester film. This was dryied at a 
temperature of 110.degree. C. for three minutes to form a 25 m-thick 
adhesive layer 13. A silicon coated peel-off sheet 14 was then superposed 
on the adhesive layer 13 with the silicon-coated surface being in contact 
therewith. The surface of the base sheet 11 opposite to the adhesive layer 
13 was coated with the color developing agent having the above 
composition, which has been dehydrated to have a solid content of 50%. 
After drying at a temperature of 100.degree. C. for one minute, a 25 
.mu.m-thick layer 12 was formed. 
The resulting sheet 20 may be used as a developer sheet as illustrated in 
FIG. 5. The color developing agent layer 12 of this sheet 20 is caused to 
contact, under pressure applied by a pair of rollers 18a and 18b, with a 
microcapsule layer 17 of microcapsule sheet 16 which has already been 
exposed to light to form thereon a latent image corresponding to a 
manuscript, so that the microcapsules not exposed to light are ruptured to 
flow out the inside dye precursor. The dye precursor reacts with the color 
developing agent of the layer 12 for color development. Thus, a photo 
image is formed on the surface 12 of the image adhesion sheet 20. The 
image adhesion sheet 20 can be adhered to any desired material by removing 
the peel-off sheet 14. 
FIG. 6 shows another image adhesion sheet 20a which is different from FIG. 
4, wherein it has a first layer 19 comprising the color developing agent 
and microcapsules each enveloping therein the dye precursor and the 
photo-curable resin. In other words, the image adhesion sheet 20a 
illustrated in FIG. 6 is of a self-developing type while the sheet 20 
shown in FIG. 4 is used as a developer sheet in a transfer type developing 
system. 
One example of the image adhesion sheet 20a will be described. The 
composition of the adhesive agent in the layer 13 and the 
microcapsules/color developing agent mixture for self-developing in the 
layer 19 are as follows: 
______________________________________ 
(parts) 
______________________________________ 
Adhesive Agent 
Butylacrylate 97 
A Acrylic acid 3 
Benzoly peroxide 0.2 
Curing agent 0.8 
Rosin ester 34 
Mixture for self-developing 
Microcapsules 100 
P-phenylphenol 50 
Phenolnovolac 50 
Polyvinilalcohol 15 
______________________________________ 
The A component of the adhesive agent was gradually added to ethyl acetate 
over four hours to obtain a copolymer having a solid content of 50%. To 
the copolymer was added the curing agent and resin ester, and the 
resulting mixture was applied to a base sheet 11 of 25 .mu.m-thick 
polyester film. After drying, a 25 m-thick adhesive layer 13 was formed. A 
silicon-coated peel-off sheet 14 was then applied onto the adhesive layer 
13 in the same manner as in the above embodiment shown in FIG. 4. The 
surface of base sheet 11 opposite to the adhesive layer 13 was coated with 
the mixture for self-developing having the above composition, which was 
then dehydrated to have a solid content of 50% and dried for one minute at 
a temperature of 100.degree. C. to provide a 50 .mu.m-thick layer 19. The 
microcapsules were prepared by a conventional core cellvation method and 
consist of a spherical sheel of gelatin enveloping therein dye precursor 
and photo-curable toluene resin solution. 
The image adhesion sheet of FIG. 6 thus prepared is exposed to light, and 
the uncured microcapsules in the layer 19 is ruptured by applying pressure 
thereto so that the inside dye precursor reacts with the color developing 
agent to develop a color photo image on the layer 19. 
Recording media shown in FIGS. 7 to 10 are provided in accordance with 
still another embodiment of this invention. The recording medium 30 
comprises a sheet shaped member 31 of a transparent material, supporting 
on its one surface the color developing agent 31, photosensitive 
microcapsules 33 and adhesive microcapsule 34. The transparent sheet 31 
may be of polyethylene, polyvinyl chloride, polymetacryl acid, 
polyethylene telefutalate, polycarbonate, nylon or any other substantial 
transparent resin or glass. The color developing agent may be any suitable 
material that reacts with the dye precursor contained in the 
photosensitive microcapsules 33 for color development. The photosensitive 
microcapsules 33 may be of conventionally known type, each containing the 
dye precursor and the photosensitive or photo-curable resin. Photo 
polymerization initiator and photo sensitizer or other suitable additives 
may be added upon demand. 
The adhesive microcapsule 34 is shown in FIG. 11, by way of example, which 
consists of a spherical outer shell 34a and a liquid adhesive 34b. The 
outer shell 34a will be made of a material which can be crushed under 
pressure or heat, such as gelatin, casein, gum arabic, polyethylene, 
polystyrene or other material which may be the same as that of the 
photosensitive microcapsules 33. The liquid adhesive 34b contained in the 
outer shell 34a may be casein or starch-based natural adhesive, a 
thermoplastic resin type adhesive obtained by dissolving vinyl chloride, 
binyl acetate, polyvinyl alcohol or acryl in a suitable solvent such as 
methylethylketone, aceton, tetrahydrofuran and cyclohexanone, or 
elastomer-based adhesive such as solution of natural rubber, reclaimed 
rubber, butadiene styrene, neoprene and chloroprene. 
The color developing agent 32, the photosensitive microcapsules 33 and the 
adhesive microcapsules 34 are supported on one surface of the transparent 
base sheet 31. For example, a layer of the color developing agent 32 is 
coated on the base sheet 31 and photosensitive microcapsules 33 and 
adhesive microcapsules 34 are dispersed at random on the layer 32, as 
illustrated in FIG. 7. FIGS. 8 , 9 and 10 show alternative embodiments. As 
shown in FIG. 8, photosensitive microcapsules 33 may be dispersed in the 
layer together with the color developing agent 32, on which adhesive 
microcapsules 34 is dispersed. In FIG. 9, photosensitive microcapsules 33 
and adhesive microcapsules 34 are both dispersed in the color developing 
agent 32. FIG. 10 illustrates another arrangement that photosensitive 
microcapsules 33 and adhesive microcapsules 34 are laminated in separate 
layers on the color developing agent 32. 
Reference is now made to FIG. 12 which shows a general arrangement of an 
image forming apparatus unitizing the recording medium 30 shown in FIG. 7. 
More particularly, an exposure system 35 radiates a light beam from a 
light source, not shown, to the recording medium 30. The recording medium 
30 comprises, as described above, the transparent base sheet 31 coated 
with the layer of the color developing agent 32 and photosensitive or 
photosetting microcapsules 33 and adhesive microcapsules 34 dispersed on 
the chromogenic material layer 32. Thus a latent image is formed on the 
recording medium 30. The exposed recording medium 30 is transferred via a 
pair of guide rollers 36a, 36b in the arrowed direction. A piece of 
ordinary paper 37 is then laid upon the exposed surface of the recording 
medium 30, both sheets being together pressed between a pair of pressure 
applying rollers 38a and 38b. In the meantime, photosensitive 
microcapsules 33, which has not been exposed to light to retain their 
original mechanical strength, are ruptured under pressure exerted by the 
rollers 38a and 38b so that the dye precursor flowing out of the ruptured 
microcapsules 33 reacts with the color developing agent 32 to develop the 
latent image on the recording medium 30. At the same time, adhesive 
microcapsules 34 are also ruptured to flow out the inside adhesive with 
which the paper 37 is bonded to the recording medium 30 when passing 
between the rollers 38a and 38b. The resulting product 40 is discharged to 
a tray 39. Seen through the transparent sheet 31, the paper 37 looks as if 
the image was actually printed thereon. 
In the foregoing description, the base sheet 31 of the recording medium 30 
is made of a transparent film is used in place of the ordinary paper 37, 
it is not necessary to prepare a transparent base sheet, in which case the 
recorded image can be seen through the transparent film.