Thermosensitive recording adhesive label

A thermosensitive recording adhesive label has a support, a thermosensitive coloring layer provided on one side of the support, and a thermosensitive adhesive layer which is formed on the other side of the support, opposite to the side of the thermosensitive coloring layer with respect to the support, and is adhesive above room temperature, with the thermosensitive coloring layer having a surface smoothness of 200 to 10,000 sec when measured by the method of Ohken-shiki prescribed in Japan Tappi No. 5, and the thermosensitive adhesive layer having a surface smoothness of 60 to 3,000 sec in terms of Bekk's smoothness.

BACKGROUND OF THE INVENTION 
FIELD OF THE INVENTION 
The present invention relates to a thermosensitive recording adhesive label 
comprising a support, a thermosensitive coloring layer formed on the front 
side of the support, and a thermosensitive adhesive layer without being 
provided with a liner (i.e., a disposable backing sheet), which is formed 
on the back side of the support and is not adhesive at room temperature 
and is heat-activated so as to become adhesive by the application of heat 
thereto. Namely, the present invention relates to a so-called liner-less 
thermosensitive recording adhesive label. 
DISCUSSION OF BACKGROUND 
Recently, a thermosensitive recording adhesive label has been used in a 
wide variety of fields, for example, in the system of Point of Sales 
(POS). However, such a conventional thermosensitive recording adhesive 
label still has many shortcomings. 
To be more specific, in the above-mentioned label, a pressure-sensitive 
adhesive layer or a room-temperature adhesive layer is provided on one 
side of a support with a liner (i.e., disposable backing sheet) being 
attached to the adhesive layer, and on the other side of the support a 
thermosensitive coloring layer is provided. 
The conventional thermosensitive recording label is commercially available 
in such a fashion that the label portions are separately arranged and 
attached to a liner sheet, or the thermosensitive recording label is 
entirely attached to the liner sheet so as to detach a necessary portion 
on a perforated line. In any case, to use such a thermosensitive recording 
adhesive label, it is necessary to release a necessary portion from the 
liner, and thereafter the liner must be discarded. Therefore, from the 
ecological viewpoint, consideration must be given to the problem of waste 
disposal. 
In addition, the liner is relatively voluminous and heavy, so that a large 
space is required during the storage of the label and the transportation 
of the label becomes a factor. Namely, although the liner is to be 
discarded at the final step, it must be attached to the adhesive layer of 
the label immediately before the recording label is used. 
To solve the above-mentioned problems, there are proposed recording labels 
without a liner, that is, liner-less thermosensitive recording adhesive 
labels. For instance, as disclosed in Japanese Laid-Open Utility Model 
Applications 59-43979 and 59-46265 and Japanese Laid-Open Patent 
Application 60-54842, the following is considered. It is proposed to 
employ a pressure-sensitive adhesive in micro-capsule form in the adhesive 
layer, and to provide a releasing agent layer on the top layer such as a 
protective layer, in light of the storage of the thermosensitive recording 
adhesive label in the form of a roll. According to the above-mentioned 
conventional proposals, however, the adhesion of the pressure-sensitive 
adhesive layer is not sufficient, and it is impossible to print an image 
on the surface of the label when the releasing agent layer is overlaid. 
These proposals have not yet been put to practical use. 
Furthermore, there is proposed a method of employing a thermosensitive 
adhesive in the adhesive layer of the thermosensitive recording adhesive 
label, as disclosed in Japanese Laid-Open Utility Model Application 
54-12446. 
The above-mentioned conventional thermosensitive recording adhesive label 
employing the thermosensitive adhesive is very useful, but it has the 
drawback that when the recording label is stored in roll form for a long 
period of time, the blocking phenomenon occurs. Even though no thermal 
energy is applied to the thermosensitive adhesive layer, the blocking 
phenomenon may occur because of the pressure due to the weight of the 
roll. To prevent this, it is necessary to decrease the strength of the 
adhesive in the thermosensitive adhesive layer. 
Furthermore, as disclosed in Japanese Laid-Open Patent Application 
63-303387 and Japanese Utility Model Publication 5-11573, it is proposed 
that, in a liner-less thermosensitive recording adhesive label, an 
intermediate layer such as an expandable insulating layer or 
non-expandable insulating layer be added so as to activate the 
thermosensitive adhesive layer efficiently. Such a liner-less 
thermosensitive recording adhesive label, provided with the intermediate 
layer, is superior to the one without the intermediate layer because the 
thermosensitive adhesive layer can be more efficiently activated by the 
application of a small amount of thermal energy, and therefore, there can 
be employed a thermosensitive adhesive which is heat-activated at high 
temperature. 
However, there is no liner-less thermosensitive recording adhesive label 
that can satisfy both situations simultaneously; sufficient adhesiveness 
and blocking resistance. 
SUMMARY OF THE INVENTION 
It is therefore a first object of the present invention to provide a 
thermosensitive recording adhesive label which can exhibit strong 
adhesiveness to a member to which the recording adhesive label is 
attached, using a thermosensitive adhesive with strong adhesiveness, and 
which does not induce the blocking phenomenon when stored in the roll 
form. 
A second object of the present invention is to provide a thermosensitive 
recording adhesive label which can show excellent image reliability 
regardless of a plasticizer contained in the thermosensitive adhesive 
layer. 
The above-mentioned objects of the present invention can be achieved by a 
thermosensitive recording adhesive label comprising a support, a 
thermosensitive coloring layer provided on one side of the support, and a 
thermosensitive adhesive layer which is formed on the other side of the 
support, opposite to the side of the thermosensitive coloring layer with 
respect to the support, and is adhesive above room temperature, the 
surface of the thermosensitive coloring layer having a surface smoothness 
of 200 to 10,000 sec when measured by the method of Ohken-shiki prescribed 
in Japan Tappi No. 5, and the surface of the thermosensitive adhesive 
layer having a surface smoothness of 60 to 3,000 sec in terms of Bekk's 
smoothness. 
DESCRIPTION OF THE PREFERRED EMBODIMENTS 
The inventors of the present invention have investigated the problems of 
the conventional thermosensitive recording adhesive label. In particular, 
special attentions have been paid to the fact that the blocking phenomenon 
occurs while a liner-less thermosensitive recording adhesive label is 
stored in the roll form so as to bring the thermosensitive adhesive layer 
into contact with the thermosensitive coloring layer. As a result of the 
intensive studies on the relation between the surface characteristics of 
the thermosensitive adhesive layer and those of the thermosensitive 
coloring layer, the inventors of the present invention have discovered 
that the blocking phenomenon can be effectively prevented when the surface 
smoothnesses of the thermosensitive adhesive layer and the thermosensitive 
coloring layer which are in contact with each other during the storage are 
controlled to specified values. 
Generally, to heat-activate the thermosensitive adhesive layer of the 
liner-less thermosensitive recording adhesive label, the thermal energy is 
applied to the side of the thermosensitive coloring layer or the side of 
the thermosensitive adhesive layer, or the adhesive label is placed into a 
temperature-controlled bath. In any case, when the thermal energy for 
activating the thermosensitive adhesive layer is too strong, the color 
development will take place in the background of the thermosensitive 
coloring layer. 
Therefore, in the course of heat-activation for the thermosensitive 
adhesive layer, it is required to apply the thermal energy to the label to 
such a degree that the color development may not occur in the background 
portion of the thermosensitive coloring layer. In this case, however, the 
thermosensitive adhesive layer cannot be provided with sufficient 
adhesiveness when the surface smoothness of the thermosensitive adhesive 
layer is too low. On the other hand, when the surface smoothness of the 
thermosensitive adhesive layer is too high, the blocking resistance is 
decreased while the adhesive label is stored in the roll form. 
Further, when the surface smoothness of the thermosensitive coloring layer 
is too low, the thermal sensitivity of the thermosensitive coloring layer 
is lowered; and when the surface smoothness of the thermosensitive 
coloring layer is too high, the blocking resistance is also decreased 
while the adhesive label is stored in the roll form. 
In the present invention, to simultaneously obtain desired adhesiveness of 
the thermosensitive adhesive layer, sufficient resistance to the blocking 
phenomenon between the thermosensitive coloring layer and the 
thermosensitive adhesive layer, and high thermal sensitivity of the 
thermosensitive coloring layer, the surface smoothness of the 
thermosensitive coloring layer is specified to 200 to 10,000 sec, 
preferably 500 to 4,000 sec when measured by the method of Ohken-shiki 
prescribed in Japan Tappi No. 5. When the surface smoothness of the 
thermosensitive coloring layer is less than 200 sec, the thermal 
sensitivity is decreased. When the surface smoothness thereof exceeds 
10,000 sec, the blocking resistance is decreased during the storage of the 
adhesive label in the roll form. 
Further, the surface smoothness of the thermosensitive adhesive layer is 
specified to 60 to 3,000 sec, preferably 100 to 2,000 sec in terms of 
Bekk's smoothness. When the surface smoothness of the thermosensitive 
adhesive layer is less than 60 sec, the thermosensitive adhesive cannot be 
efficiently heat-activated. When the surface smoothness thereof exceeds 
3,000 sec, the blocking resistance is decreased during the storage of the 
adhesive label in the roll form. 
The smoothness of the thermosensitive coloring layer is measured using a 
smoothness tester of Ohken-shiki prescribed in Japan Tappi No. 5. To be 
more specific, a sample of the thermosensitive recording adhesive label is 
placed on a measuring head with the thermosensitive coloring layer being 
directed to the head, a load is applied to the sample, and the scale mark 
of a scale plate corresponding to the height of a manometer is read after 
the value of the manometer is stabilized (about two minutes). 
With respect to the smoothness of the thermosensitive adhesive layer, the 
smoothness is measured using a Bekk's smoothness tester. In the case where 
air of 10 ml takes 300 seconds or less to pass through the gap between a 
sample film of the thermosensitive adhesive layer and a glass plate, the 
time (second) required for the mercury column to decrease by 20 mm may be 
measured. In the case where it takes 300 seconds or more, the time 
(second) required for the mercury column to decrease by 2 mm is measured, 
and then the obtained value may be increased by ten times in accordance 
with Japanese Industrial Standard (JIS) P8119. 
The above specified smoothness of the thermosensitive adhesive layer can be 
obtained, for example, by adjusting the particle size of a solid 
plasticizer to be added to the thermosensitive adhesive layer, and 
subjecting the obtained thermosensitive adhesive layer to calendering 
after drying. 
The thermosensitive coloring layer can be provided with the previously 
specified smoothness, for example, by adjusting the particle size of the 
components contained in the thermosensitive coloring layer, controlling 
the water content of the thermosensitive coloring layer, and subjecting 
the obtained thermosensitive coloring layer to calendering after drying. 
The thermosensitive adhesive for use in the thermosensitive adhesive layer 
comprises: 
a polymeric resin which is provided with adhesiveness by the application of 
heat thereto; 
a plasticizer which assumes a solid state at room temperature (hereinafter 
referred to as a solid plasticizer), and is melted by the application of 
heat thereto so as to make the polymeric resin adhesive; and 
a tackifier for further strengthening the adhesiveness when necessary. 
The polymeric resin for use in the thermosensitive adhesive is not 
particularly limited in the present invention, but the following polymeric 
resins can be preferably employed: polyvinyl acetate, polybutyl 
methacrylate, vinyl ether-vinylidene chloride copolymer, synthetic rubber, 
vinyl acetate-2-ethylhexyl acrylate copolymer, vinyl acetate-ethylene 
copolymer, vinyl pyrrolidone-styrene copolymer, styrene-butadiene 
copolymer, vinyl pyrrolidone-ethyl acrylate copolymer, and acryl-butadiene 
copolymer. 
Of these polymeric resins, an acryl-butadiene copolymer is particularly 
preferable in the present invention. To prepare such an acryl-butadiene 
copolymer, the following acryl monomers can be used as copolymerizable 
monomers with butadiene: methacrylic ester such as methyl methacrylate 
(MMA), methacrylic acid, acrylic ester, acrylic acid, acrylonitrile, 
acrylamide, and N-methylolacrylamide. 
Of the thus obtained acryl-butadiene copolymers, methyl methacrylate 
(MMA)-butadiene copolymer is further preferably employed because the 
obtained thermosensitive adhesive shows strong adhesiveness to any 
adherend, especially to vinyl chloride wraps and polyethylene wraps, and 
sufficient blocking resistance can be obtained. 
Further, when the above-mentioned methyl methacrylate (MMA)-butadiene 
copolymer is used in combination with a styrene-acryl copolymer, the 
adhesiveness to the adherend is further improved, and the blocking 
resistance is also further improved. To prepare such a styrene-acryl 
copolymer, the following acryl monomers can be used as copolymerizable 
monomers with styrene: methacrylic ester, methacrylic acid, acrylic ester, 
acrylic acid, acrylonitrile, acrylamide, and N-methylolamide. 
In such a case, it is preferable that the amount ratio by weight of the 
acryl-butadiene copolymer to the styrene-acryl copolymer be in the range 
of (1:0.2) to (1:5), more preferably in the range of (1:0.3) to (1:3). 
When the amount ratio of the acryl-butadiene copolymer to the 
styrene-acryl copolymer is within the above range, the blocking resistance 
of the obtained thermosensitive adhesive layer is satisfactory and the 
adhesiveness to vinyl chloride wraps or polyethylene wraps is sufficient. 
Examples of the solid plasticizer for use in the thermosensitive adhesive 
are as follows: diphenyl phthalate, dihexyl phthalate, dicyclohexyl 
phthalate, dihydroabietyl phthalate, dimethyl isophthalate, sucrose 
benzoate, ethylene glycol dibenzoate, trimethylolethane tribenzoate, 
glyceride tribenzoate, pentaerythritol tetrabenzoate, sucrose octacetate, 
tricyclohexyl citrate, and N-cyclohexyl-p-toluenesulfonamide. 
It is preferable that the amount of the solid plasticizer in the 
thermosensitive adhesive be in the range of 30 to 70 wt. %, more 
preferably in the range of 35 to 65 wt. %, of the total weight of the 
thermosensitive adhesive. When the content of the solid plasticizer is 
within the above-mentioned range, sufficient adhesion can be obtained. 
Examples of the tackifier for use in the thermosensitive adhesive are as 
follows: rosin and derivatives thereof, for example, polymerized rosin, 
hydrogenated rosin, esters of the above-mentioned rosin such as glycerin 
and pentaerythritol, and dimers of resin acid; terpene resin; petroleum 
resin; phenolic resin; and xylene resin. 
It is preferable that the melting point or the softening point of the 
above-mentioned tackifier be 100.degree. C. or more, more preferably in 
the range of 100 to 200.degree. C. When the melting point or softening 
point of the tackifier is 100.degree. C. or more, the blocking resistance 
of the obtained thermosensitive recording adhesive label does not 
decrease. 
It is preferable that the amount of tackifier be in the range of 3 to 30 
wt. %, and more preferably 5 to 25 wt. % of the total weight of the 
thermosensitive adhesive. When the amount of tackifier is within the 
above-mentioned range, the decrease of adhesiveness and the decrease of 
blocking resistance can be prevented. 
In the present invention, the thermosensitive recording adhesive label may 
further comprise a barrier layer which is provided between the support and 
the thermosensitive adhesive layer and/or between the support and the 
thermosensitive coloring layer so as not to allow the activated 
thermosensitive adhesive to penetrate through the support and enter the 
thermosensitive coloring layer. Thus, the effective amount of 
thermosensitive adhesive can be maintained and the plasticizer contained 
in the thermosensitive adhesive layer can be prevented from penetrating 
into the thermosensitive coloring layer. 
It is preferable that the barrier layer for use in the present invention 
have an air permeability of 10,000 sec or more, and more preferably 20,000 
sec or more, when measured by the method of Ohken-shiki prescribed in 
Japan Tappi No. 5. When the air permeability of the barrier layer is 
10,000 sec or more, the barrier effect against the plasticizer contained 
in the thermosensitive adhesive layer is more significant. 
The air permeability of the barrier layer can be controlled to 10,000 sec 
or more by selecting the resin and other additives to be contained in the 
barrier layer, and adjusting the thickness of the barrier layer. Thus, the 
preferable deposition amount of a coating liquid for formation of the 
barrier layer is about 0.5 g/m.sup.2 or more on a dry basis. 
The barrier layer comprises a resin and other additives. 
Any resins that have film-forming properties are available for the 
formation of the barrier layer. Specific examples of the resin for the 
formation of the barrier layer are as follows: emulsions of 
styrene-butadiene copolymer, styrene-butadiene-acryl copolymer, vinyl 
acetate resin, vinyl acetate-acrylic acid copolymer, styrene-acrylic ester 
copolymer, acrylic ester resin, and polyurethane resin; latexes of SBR, 
MBR, and NBR; and water-soluble polymeric resins such as polyvinyl 
alcohol, cellulose derivative, starch and derivatives thereof, 
carboxyl-group-modified polyvinyl alcohol, polyacrylic acid and 
derivatives thereof, styrene-acrylic acid copolymer and derivatives 
thereof, poly(meth)acrylamide and derivatives thereof, styrene-acrylic 
acid-acrylamide copolymer, amino-group-modified polyvinyl alcohol, 
epoxy-modified polyvinyl alcohol, polyethyleneimine, and 
isobutylene-maleic anhydride copolymer and derivatives thereof. 
The above-mentioned barrier layer may further comprise a filler. Examples 
of such a filler include finely-divided particles of inorganic fillers 
such as calcium carbonate, silica, zinc oxide, titanium oxide, aluminum 
hydroxide, zinc hydroxide, barium sulfate, clay, talc, and surface-treated 
calcium and silica; and finely-divided particles of organic fillers such 
as urea-formaldehyde resin, styrene-methacrylic acid copolymer, and 
polystyrene resin. 
In light of the effect of preventing the peeling of the thermosensitive 
adhesive layer and the thermosensitive coloring layer, it is preferable 
that the barrier layer comprise any of the above-mentioned water-soluble 
polymeric resins and a waterproofing agent. 
As the waterproofing agent for use in the barrier layer, there can be 
employed water-soluble resins, for example, polyamide epichlorohydrin, 
aziridine alkyl ester, melamine, and glycerin glycidyl ether. 
Furthermore, the thermosensitive recording adhesive label may further 
comprise a heat insulating layer which is interposed between the support 
and the thermosensitive coloring layer and/or between the support and the 
thermosensitive adhesive layer. By provision of the insulating layer 
between the support and the thermosensitive coloring layer, the thermal 
energy applied by a heating element such as a thermal head can be 
efficiently utilized, so that the coloring sensitivity of the 
thermosensitive coloring layer is improved. Owing to the heat insulating 
layer between the support and the thermosensitive adhesive layer, the 
thermosensitive adhesive layer can be efficiently heat-activated. Thus, it 
is possible to widen the difference between the heat-activation 
temperature of the thermosensitive adhesive layer and the color 
development initiation temperature of the thermosensitive coloring layer. 
In the present invention, there can be employed an insulating layer 
comprising minute void particles with a voidage of 30% or more, each 
comprising a thermoplastic resin for forming a shell. Non-expandable or 
expandable fillers can be used for forming the minute void particles. 
The non-expandable minute void particles for use in the insulating layer, 
which are in an expanded state, contain air or other gases therein. It is 
preferable to employ the minute void particles with an average particle 
size of 0.4 to 20 .mu.m, more preferably 0.5 to 10 .mu.m, and further 
preferably 3 to 8 .mu.m. When the average particle diameter (outer 
diameter) of the minute void particles is 0.4 .mu.m or more, void 
particles with a desired voidage can be produced with no difficulty. When 
the average particle diameter (outer diameter) of the minute void 
particles is 20 .mu.m or less, the surface smoothness of the obtained 
insulating layer is not so lowered that the matching properties of the 
thermosensitive coloring layer with the thermal head are satisfactory. 
Accordingly, the decrease of dot-reproduction performance and thermal 
sensitivity can be avoided. It is also preferable that the above-mentioned 
minute void particles be classified in a uniform particle size spectrum. 
The voidage of the minute void particles for use in the insulating layer is 
preferably 30% or more, and more preferably 50% or more. When the 
insulating layer interposed between the support and the thermosensitive 
coloring layer has a voidage of 30% or more, sufficient insulating 
properties can be obtained. Therefore, the thermal energy for color 
development of the thermosensitive coloring layer, which is generated, for 
example, by a thermal head, can be efficiently utilized in the 
thermosensitive coloring layer without escaping through the support, 
thereby improving the coloring sensitivity. In addition, due to the 
insulating layer between the support and the thermosensitive adhesive 
layer, the thermal energy applied to the thermosensitive adhesive layer 
for heat-activation can be efficiently used in the thermosensitive 
adhesive layer, so that sufficient adhesion can be exhibited. 
The voidage of minute void particles means a ratio of the inner diameter to 
the outer diameter of void particles, which is expressed by the following 
formula: 
##EQU1## 
The minute void particles comprise a thermoplastic resin for forming a 
shell therefor, as previously mentioned. As the above-mentioned 
thermoplastic resin, a copolymer resin comprising as the main components 
vinylidene chloride and acrylonitrile is preferably employed. 
To provide the non-expandable insulating layer on the support, the 
above-mentioned minute void particles may be dispersed in water together 
with a binder agent such as a conventionally known water-soluble polymer 
or an aqueous polymer emulsion so as to prepare a coating liquid for the 
formation of the insulating layer. The coating liquid thus prepared may be 
coated on the support and dried, so that an insulating layer is provided 
on the support. In such a case, it is preferable that the deposition 
amount of the minute void particles be at least 1 g/m.sup.2, and more 
preferably in the range of about 2 to 15 g/m.sup.2. The binder agent for 
use in the coating liquid for the non-expandable insulating layer may be 
in such an amount that can stably bind the insulating layer to the 
support, and in general, the amount of binder agent may be in the range of 
2 to 50 wt. % of the total weight of the minute void particles and the 
binder agent. 
When the expandable filler is used for formation of the expandable 
insulating layer, there can be employed plastic void filler particles, 
each comprising a thermoplastic resin for forming a shell therefor and a 
blowing agent such as a low boiling point solvent therein. Those void 
plastic filler particles are expanded by the application of heat thereto. 
Such an expandable plastic filler is conventionally known. It is 
preferable that the particle size of the expandable plastic filler be in 
the range of 2 to 50 .mu.m, and more preferably 5 to 20 .mu.m in a 
non-expanded state; and in the range of 10 to 100 .mu.m, and more 
preferably 10 to 50 .mu.m in an expanded state. 
Examples of the thermoplastic resin for forming the shell for the 
expandable plastic filler particles are polystyrene, polyvinyl chloride, 
polyvinylidene chloride, polyvinyl acetate, polyacrylate, 
polyacrylonitrile, polybutadiene and copolymers comprising monomers 
constituting the above-mentioned resins. 
As the blowing agent, propane or butane is generally employed. 
When such an expandable insulating layer is provided on the support, a 
mixture of the above-mentioned expandable plastic filler and a binder 
agent is coated on the support and dried, and thereafter the plastic 
filler may be caused to blow with the application of heat thereto by 
bringing a heated plate into contact with the surface of the coated layer. 
It is preferable that the deposition amount of the plastic filler be at 
least 1 g/m.sup.2, and more preferably about 2 to 5 g/m.sup.2 in a 
non-expanded state. The binder agent may be added to the plastic filler in 
such an amount that can firmly bind the obtained expandable insulating 
layer to the support. In general, the amount of binder agent is in the 
range of 5 to 50 wt. % of the total weight of the non-expanded plastic 
filler and the binder agent. The blowing temperature of the plastic filler 
is a softening point of the thermoplastic resin constituting the shell of 
the plastic filler particles. It is preferable that the blowing 
magnification be 2 to 4 times, and more preferably 2 to 3 times. 
The surface of the obtained insulating layer of an expanded type is 
considerably rough, so that it is preferable to subject the insulating 
layer to surface treatment by calendering after expanding the plastic 
filler particles by the application of heat thereto. When necessary, at 
least one undercoat layer may be provided over the obtained insulating 
layer. Such an undercoat may also be provided under the insulating layer. 
The above-mentioned insulating layer may further comprise auxiliary 
additives which are conventionally used in this kind of thermosensitive 
recording material, for example, a thermofusible material and a 
surfactant. The same thermofusible materials for use in the 
thermosensitive coloring layer, which will be described later, are usable 
in the insulating layer. 
For the formation of the insulating layer comprising the minute void 
particles, the conventional water-soluble polymers and/or aqueous polymer 
emulsions are used as the binder agents. 
Examples of the above-mentioned water-soluble polymers are polyvinyl 
alcohol, starch and derivatives thereof, cellulose derivatives such as 
methoxy cellulose, hydroxy cellulose, carboxymethyl cellulose, methyl 
cellulose and ethyl cellulose, sodium polyacrylate, polyvinyl pyrrolidone, 
acrylamide-acrylic ester copolymer, acrylamide-acrylic ester-methacrylic 
acid terpolymer, alkali salts of styrene-maleic anhydride copolymer, 
alkali salts of isobutylene-maleic anhydride copolymer, polyacrylamide, 
sodium alginate, gelatin, and casein. 
Examples of the aqueous polymer emulsions for use in the insulating layer 
include latexes of styrene-butadiene copolymer and 
styrene-butadiene-acrylic copolymer; and emulsions of vinyl acetate resin, 
vinyl acetate-acrylic acid copolymer, styrene-acrylic ester copolymer, 
acrylic ester resin, and polyurethane resin. 
The above-mentioned barrier layer and the heat insulating layer may be 
simultaneously provided between the support and the thermosensitive 
coloring layer and/or between the support and the thermosensitive adhesive 
layer. The barrier layer and the insulating layer may be overlaid on the 
support in any order. In the case where both layers are interposed between 
the support and the thermosensitive coloring layer, it is preferable to 
provide on the support in such an order of the barrier layer, the 
insulating layer and the thermosensitive coloring layer. This is because 
the thermal energy applied to the thermosensitive coloring layer for color 
development can be more efficiently used. 
In light of the structure of the layers for practical use, it is preferable 
that the insulating layer and the thermosensitive coloring layer be 
successively provided on the front side of the support and the barrier 
layer and the thermosensitive adhesive layer be successively provided on 
the back side of the support. Alternatively, it is preferable that the 
barrier layer, the insulating layer and the thermosensitive coloring layer 
be provided on the front side of the support, and the thermosensitive 
adhesive layer be provided on the back side of the support. 
The thermosensitive coloring layer comprises a coloring composition which 
can induce color formation by the application of heat thereto. For 
instance, the above-mentioned coloring composition comprises a coloring 
agent such as a leuco dye, and a color developer. 
As the leuco dye for use in the present invention, which may be employed 
alone or in combination, any conventional dyes for use in the conventional 
leuco-dye-containing recording materials can be employed. For example, 
triphenylmethane leuco compounds, fluoran leuco compounds, phenothiazine 
leuco compounds, auramine leuco compounds, spiropyran leuco compounds, and 
indolinophthalide leuco compounds are preferably employed. Specific 
examples of those leuco dyes are as follows: 
3,3-bis(p-dimethylaminophenyl)phthalide, 
3,3-bis(p-dimethylaminophenyl)-6-dimethylaminophthalide (or Crystal Violet 
Lactone), 
3,3-bis(p-dimethylaminophenyl)-6-diethylaminophthalide, 
3,3-bis(p-dimethylaminophenyl)-6-chlorophthalide, 
3,3-bis(p-dibutylaminophenyl)phthalide, 
3-cyclohexylamino-6-chlorofluoran, 
3-dimethylamino-5,7-dimethylfluoran, 
3-diethylamino-7-chlorofluoran, 
3-diethylamino-7-methylfluoran, 
3-diethylamino-7,8-benzfluoran, 
3-diethylamino-6-methyl-7-chlorofluoran, 
3-(N-p-tolyl-N-ethylamino)-6-methyl-7-anilinofluoran, 
3-pyrrolidino-6-methyl-7-anilinofluoran, 
2-N-(3'-trifluoromethylphenyl)amino!-6-diethylaminofluoran, 
2-3,6-bis(diethylamino)-9-(o-chloroanilino)xanthylbenzoic acid lactam!, 
3-diethylamino-6-methyl-7-(m-trichloromethylanilino)fluoran, 
3-diethylamino-7-(o-chloroanilino)fluoran, 
3-di-n-butylamino-7-(o-chloroanilino)fluoran, 
3-N-methyl-N,n-amylamino-6-methyl-7-anilinofluoran, 
3-N-methyl-N-cyclohexylamino-6-methyl-7-anilinofluoran, 
3-diethylamino-6-methyl-7-anilinofluoran, 
3-(N,N-diethylamino)-5-methyl-7-(N,N-dibenzylamino)fluoran, 
benzoyl leuco methylene blue, 
6'-chloro-8'-methoxy-benzoindolino-spiropyran, 
6'-bromo-3'-methoxy-benzoindolino-spiropyran, 
3-(2'-hydroxy-4'-dimethylaminophenyl)-3-(2'-methoxy-5'-chlorophenyl)phthali 
de, 
3-(2'-hydroxy-4'-dimethylaminophenyl)-3-(2'-methoxy-5'-nitrophenyl)phthalid 
e, 
3-(2'-hydroxy-4'-diethylaminophenyl)-3-(2'-methoxy-5'-methylphenyl)phthalid 
e, 
3-(2'-methoxy-4'-dimethylaminophenyl)-3-(2'-hydroxy-4'-chloro-5'-methylphen 
yl)phthalide, 
3-(N-ethyl-N-tetrahydrofurfuryl)amino-6-methyl-7-anilinofluoran, 
3-N-ethyl-N-(2-ethoxypropyl)amino-6-methyl-7-anilinofluoran, 
3-N-methyl-N-isobutyl-6-methyl-7-anilinofluoran, 
3-morphorino-7-(N-propyl-trifluoromethylanilino)fluoran, 
3-pyrrolidino-7-m-trifluoromethylanilinofluoran, 
3-diethylamino-5-chloro-7-(N-benzyl-trifluoromethylanilino)fluoran, 
3-pyrrolidino-7-(di-p-chlorophenyl)methylaminofluoran, 
3-diethylamino-5-chloro-7-(.alpha.-phenylethylamino)fluoran, 
3-(N-ethyl-p-toluidino)-7-(.alpha.-phenylethylamino)fluoran, 
3-diethylamino-7-(o-methoxycarbonylphenylamino)fluoran, 
3-diethylamino-5-methyl-7-(.alpha.-phenylethylamino)fluoran, 
3-diethylamino-7-piperidinofluoran, 
2-chloro-3-(N-methyltoluidino)-7-(p-n-butylanilino)fluoran, 
3-(N-methyl-N-isopropylamino)-6-methyl-7-anilinofluoran, 
3-di-n-butylamino-6-methyl-7-anilinofluoran, 
3,6-bis(dimethylamino)fluorenespiro(9,3')-6'-dimethylaminophthalide, 
3-(N-benzyl-N-cyclohexylamino)-5,6-benzo-7-.alpha.-naphthylamino-4'-bromofl 
uoran, 
3-diethylamino-6-chloro-7-anilinofluoran, 
3-diethylamino-6-methyl-7-mesidino-4',5'-benzofluoran, 
3-N-methyl-N-isopropyl-6-methyl-7-anilinofluoran, 
3-N-ethyl-N-isoamyl-6-methyl-7-anilinofluoran, and 
3-diethylamino-6-methyl-7-(2',4'-dimethylanilino)fluoran. 
As the color developer for use in the thermosensitive coloring layer, there 
can be employed a variety of electron-acceptor compounds and oxidizing 
agents which are capable of inducing color formation in the 
above-mentioned leuco dyes when coming in contact with the leuco dyes 
under application of heat thereto. 
Specific examples of the color developer for use in the present invention 
are as follows: 
4,4'-isopropylidenediphenol, 
4,4'-isopropylidenebis(o-methylphenol), 
4,4'-sec-butylidenebisphenol, 
4,4'-isopropylidenebis(2-tert-butylphenol), 
zinc p-nitrobenzoate, 
1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)isocyanuric acid, 
2,2-(3,4'-dihydroxydiphenyl)propane, 
bis(4-hydroxy-3-methylphenyl)sulfide, 
4-.beta.-(p-methoxyphenoxy)ethoxy!salicylic acid, 
1,7-bis(4-hydroxyphenylthio)-3,5-dioxaheptane, 
1,5-bis(4-hydroxyphenylthio)-5-oxapentane, 
monocalcium salt of monobenzyl phthalate, 
4,4'-cyclohexylidenediphenol, 
4,4'-isopropylidenebis(2-chlorophenol), 
2,2'-methylenebis(4-methyl-6-tert-butylphenol), 
4,4'-butylidenebis(6-tert-butyl-2-methyl)phenol, 
1,1,3-tris(2-methyl-4-hydroxy-5-tertbutylphenyl)butane, 
1,1,3-tris(2-methyl-4-hydroxy-5-cyclohexylphenyl)butane, 
4,4'-thiobis(6-tert-butyl-2-methyl)phenol, 
4,4'-diphenolsulfone, 
4-isopropoxy-4'-hydroxydiphenylsulfone, 
4-benzyloxy-4'-hydroxydiphenylsulfone, 
4,4'-diphenolsulfoxide, 
isopropyl p-hydroxybenzoate, 
benzyl p-hydroxybenzoate, 
benzyl protocatechuate, 
stearyl gallate, 
lauryl gallate, 
octyl gallate, 
1,3-bis(4-hydroxyphenylthio)propane, 
N,N'-diphenylthiourea, 
N,N'-di(m-chlorophenyl)thiourea, 
salicylanilide, 
bis(4-hydroxyphenyl)methyl acetate, 
bis(4-hydroxyphenyl)benzyl acetate, 
1,3-bis(4-hydroxycumyl)benzene, 
1,4-bis(4-hydroxycumyl)benzene, 
2,4'-diphenolsulfone, 
2,2'-diallyl-4,4'-diphenolsulfone, 
3,4-dihydroxyphenyl-4'-methyldiphenylsulfone, 
zinc 1-acetyloxy-2-naphthoate, 
zinc 2-acetyloxy-1-naphthoate, 
zinc 2-acetyloxy-3-naphthoate, 
.alpha.,.alpha.-bis(4-hydroxyphenyl)-.alpha.-methyltoluene, 
antipyrine complex of zinc thiocyanate, 
tetrabromobisphenol A, 
tetrabromobisphenol S, 
4,4'-thiobis(2-methylphenol), and 
4,4'-thiobis(2-chlorophenol). 
Those color developers may be used alone or in combination. 
In the thermosensitive coloring layer, it is preferable that the amount of 
the color developer be one to 20 parts by weight, more preferably 2 to 10 
parts by weight, to one part by weight of the coloring agent. 
The thermosensitive coloring layer may further comprise a binder resin. 
Particularly, binder resins having a hydroxyl group or carboxyl group in a 
molecule thereof are preferably employed. 
Specific examples of the above-mentioned binder resin for use in the 
thermosensitive coloring layer are polyvinyl butyral, polyvinyl acetal 
such as polyvinyl acetoacetal, cellulose derivatives such as ethyl 
cellulose, cellulose acetate, cellulose acetate propionate and cellulose 
acetate butyrate, and epoxy resin. Those binder resins can be used alone 
or in combination. 
The thermosensitive coloring layer is provided on the support in such a 
manner that the coloring agent, color developer and binder resin are 
uniformly dispersed or dissolved in an organic solvent to prepare a 
coating liquid, and the coating liquid thus prepared is coated on the 
support and dried. In this case, the coating method is not particularly 
limited. 
It is preferable that the size of the particles dispersed in the coating 
liquid for the thermosensitive coloring layer be 10 .mu.m or less, more 
preferably 5 .mu.m or less, and further preferably 1 .mu.m or less. 
The thickness of the thermosensitive coloring layer, which depends on the 
formulation for the thermosensitive coloring layer and the application of 
the obtained thermosensitive recording adhesive label, is preferably in 
the range of about 1 to 50 .mu.m, and more preferably about 3 to 20 .mu.m. 
In order to improve the coating characteristics of the thermosensitive 
coloring layer coating liquid and upgrading the coloring characteristics 
of the obtained thermosensitive coloring layer, the thermosensitive 
coloring layer coating liquid may further comprise auxiliary additive 
components such as a filler, a surfactant, a lubricant and an agent for 
preventing color formation by pressure application, which are used in the 
conventional thermosensitive recording materials. 
Examples of the filler for use in the thermosensitive coloring layer are 
finely-divided particles of inorganic fillers such as calcium carbonate, 
silica, zinc oxide, titanium oxide, aluminum hydroxide, zinc hydroxide, 
barium sulfate, clay, kaolin, talc, and surface-treated calcium and 
silica; and finely-divided particles of organic fillers such as 
urea-formaldehyde resin, styrene-methacrylic acid copolymer, polystyrene 
resin and vinylidene chloride resin. 
Examples of the lubricant for use in the thermosensitive coloring layer are 
higher fatty acids and metallic salts thereof, higher fatty amides, higher 
fatty acid esters, and a variety of waxes such as an animal wax, a 
vegetable wax, a mineral wax and a petroleum wax. 
For the support of the thermosensitive recording adhesive label according 
to the present invention, there can be employed not only a sheet of paper; 
but also a film made of a polyester such as polyethylene terephthalate or 
polybutylene terephthalate, a cellulose derivative such as cellulose 
triacetate, a polyolefin such as polypropylene or polyethylene, or a 
polystyrene. Further, a laminated material of the above-mentioned films is 
usable. 
The thermosensitive coloring layer may further comprise a protective layer, 
which is provided at the top position. When the protective layer is 
overlaid, the surface of the protective layer has a smoothness of 200 to 
10,000 sec when measured by the method of Ohken-shiki prescribed in Japan 
Tappi No. 5. 
The protective layer for use in the present invention is considered to be 
important in light of the improvement of the chemical resistance, water 
resistance, wear resistance, light resistance and head-matching properties 
of the obtained label. 
The protective layer for use in the present invention may be a film 
comprising as the main component a water-soluble resin or hydrophobic 
resin, or a film comprising as the main component an ultraviolet-curing 
resin or electron-beam curing resin. 
Examples of the water-soluble resin for use in the protective layer are 
polyvinyl alcohol, modified polyvinyl alcohol, cellulose derivatives such 
as methyl cellulose, methoxy cellulose and hydroxy cellulose, casein, 
gelatin, polyvinyl pyrrolidone, styrene-maleic anhydride copolymer, 
diisobutylene-maleic anhydride copolymer, polyacrylamide, modified 
polyacrylamide, methyl vinyl ether-maleic anhydride copolymer, 
carboxyl-modified polyethylene, polyvinyl alcohol-polyacrylamide block 
copolymer, melamine-formaldehyde resin, and urea-formaldehyde resin. 
Examples of the resin for an aqueous emulsion and the hydrophobic resin for 
use in the protective layer include polyvinyl acetate, polyurethane, 
styrene-butadiene copolymer, styrene-butadiene-acrylic copolymer, 
polyacrylic acid, polyacrylic ester, vinyl chloride-vinyl acetate 
copolymer, polybutyl methacrylate, polyvinyl butyral, polyvinyl acetal, 
ethyl cellulose, and ethylene-vinyl acetate copolymer. Further, a 
copolymer comprising a monomer constituting the above-mentioned resins and 
a silicone segment may also be preferably employed. Those resins may be 
used alone or in combination. When necessary, the resin may be cured using 
a curing agent. 
The ultraviolet-curing resin for use in the protective layer is prepared by 
polymerizing a monomer, oligomer or prepolymer which is polymerizable to 
form a cured resin by the application of ultraviolet light thereto. There 
are no limitations on such a monomer, oligomer or prepolymer for the 
preparation of the ultraviolet-curing resin for use in the protective 
layer, but conventional monomers, oligomers, or prepolymers can be 
employed. 
There are no particular limitations on the electron-beam curing resin for 
use in the protective layer. An electron-beam curing resin comprising a 
polyester skeleton with a five or more functional branched molecular 
structure, and a silicone-modified electron-beam curing resin are 
preferred in the present invention. 
In order to further improve the matching properties of the obtained 
recording label to a thermal head, the protective layer may further 
comprise an inorganic and organic filler, and a lubricant so long as the 
surface smoothness of the protective layer is not decreased. 
It is preferable that the particle size of the filler for use in the 
protective layer be 0.3 .mu.m or less. Further, the oil absorption of the 
filler is preferably 30 ml/100 g or more, and more preferably, 80 ml/100 g 
or more. 
The above-mentioned inorganic and organic filler for use in the protective 
layer, which may be used alone or in combination, can be selected from any 
pigments used in the conventional thermosensitive recording materials. 
Specific examples of the inorganic pigment for use in the protective layer 
are calcium carbonate, silica, zinc oxide, titanium oxide, aluminum 
hydroxide, zinc hydroxide, barium sulfate, clay, talc, and surface-treated 
calcium and silica. 
Specific examples of the organic pigment for use in the protective layer 
are urea-formaldehyde resin, styrene-methacrylic acid copolymer and 
polystyrene resin. 
The protective layer may be provided by any of the conventional coating 
methods. It is preferable that the thickness of the protective layer be in 
the range of 0.1 to 20 .mu.m, and more preferably in the range of 0.5 to 
10 .mu.m. When the thickness of the protective layer is within the 
above-mentioned range, the functions of the protective layer, that is, the 
improvements of preservation stability of the recording label and 
head-matching properties of the thermosensitive coloring layer can be 
sufficiently expected, and the decrease of thermal sensitivity of the 
thermosensitive coloring layer can be prevented. 
Furthermore, in the thermosensitive recording adhesive label of the present 
invention, the thermosensitive adhesive layer and/or the intermediate 
layer (i.e. the heat insulating layer or the barrier layer) provided 
between the support and the thermosensitive adhesive layer may further 
comprise an infrared absorption material in order to activate the 
thermosensitive adhesive layer more efficiently by the exposure to halogen 
lamp or xenon lamp. 
As the above-mentioned infrared absorption material, there can be employed 
organic or inorganic compounds which can show absorption peaks in the 
infrared region of 0.7 to 20 .mu.m. In the present invention, carbon is 
preferably employed as the infrared absorption material. 
To activate the thermosensitive adhesive layer of the thermosensitive 
recording adhesive label according to the present invention, a 
heat-application roller, hot plate, thermal head, heated air, and light 
application may be employed. 
Further, a heat pen, thermal head and laser beam can be used for recording 
information in the thermosensitive coloring layer.

Other features of this invention will become apparent in the course of the 
following description of exemplary embodiments, which are given for 
illustration of the invention and are not intended to be limiting thereof. 
EXAMPLE 1 
Preparation of Thermosensitive Recording Adhesive Label 
Formation of insulating layer 
The following components were stirred and dispersed, so that a coating 
liquid for a non-expandable insulating layer was prepared: 
______________________________________ 
Parts by Weight 
______________________________________ 
Aqueous dispersion of minute 
30 
void particles (copolymer resin 
comprising vinylidene chloride and 
acrylonitrile as the main 
components) 
(solid content: 32%, 
average particle diameter: 5 .mu.m, 
and voidage: 92%) 
Styrene - butadiene copolymer latex 
10 
Water 60 
______________________________________ 
The thus prepared insulating layer coating liquid was coated on a sheet of 
high quality paper with a basis weight of 80 g/m.sup.2 serving as a 
support, and dried in such a fashion that the deposition amount of the 
coating liquid was 5 g/m.sup.2 on a dry basis. Thus, a non-expandable 
insulating layer was provided on the support. 
Formation of thermosensitive coloring layer 
A mixture of the following components was separately dispersed and 
pulverized in a sand mill until the average particle size reached 2.0 
.mu.m or less, thereby obtaining a Liquid A and a Liquid B: 
______________________________________ 
Parts by Weight 
______________________________________ 
Liquid A! 
3-dibenzylamino-6-methyl- 
20 
7-anilinofluoran 
10% aqueous solution of 
10 
polyvinyl alcohol 
Water 70 
Liquid B! 
4,4'-dihydroxybenzophenone 
20 
10% aqueous solution of 
10 
polyvinyl alcohol 
Calcium carbonate 3 
Water 67 
______________________________________ 
One part by weigh of the Liquid A and four parts by weight of the Liquid B 
were mixed and stirred, so that a coating liquid C was prepared. 
Then, a mixture of the following components was dispersed in a sand mill 
for one hour, so that a coating liquid D for the formation of a protective 
layer was prepared: 
______________________________________ 
Parts by Weight 
______________________________________ 
Liquid D! 
Silica 4 
10% aqueous solution of 
60 
itaconic-acid-modified 
polyvinyl alcohol 
(degree of saponification: 
87 mol %) 
30% aqueous dispersion of 
2 
zin stearate 
12.5% aqueous solution of 
20 
polyamide epichlorohydrin 
Water 14 
______________________________________ 
On the above obtained insulating layer, the coating liquid C was coated and 
dried in such a fashion that the deposition amount of the coating liquid C 
was 4 g/m.sup.2 on a dry basis. 
Thereafter, the coating liquid D was coated and dried in such a fashion 
that the deposition amount of the coating liquid D was 3 g/m.sup.2 on a 
dry basis. 
Thus, a thermosensitive coloring layer comprising a protective layer was 
provided on the insulating layer. 
Then, the surface of the coated layer was subjected to a supercalendering 
treatment twice at a calendering speed of 15 m/min with the application of 
a load of 30 kg thereto so as to have a surface smoothness of 2,000 sec in 
accordance with the method of Ohken-shiki prescribed in Japan Tappi No. 5. 
Formation of barrier layer 
A mixture of the following components was stirred and dispersed, so that a 
barrier layer coating liquid was prepared: 
______________________________________ 
Parts by Weight 
______________________________________ 
10% aqueous solution of 
50 
polyvinyl alcohol 
Aluminum hydroxide 
5 
10% aqueous solution of 
20 
polyamide epichlorohydrin 
Water 25 
______________________________________ 
On the back side of the support, opposite to the side of the 
thermosensitive coloring layer with respect to the support, the barrier 
layer coating liquid was coated and dried in such a fashion that the 
deposition amount of the coating liquid was 3 g/m.sup.2 on a dry basis. 
Thus, a barrier layer was provided on the back side of the support. In this 
case, the air permeability of the obtained barrier layer was infinity 
(.infin.). 
Formation of Thermosensitive Adhesive Layer 
A mixture of the following components was dispersed in a ball mill until 
the particle diameter reached 3.0 .mu.m or less, so that a thermosensitive 
adhesive layer coating liquid was prepared: 
______________________________________ 
Parts by Weight 
______________________________________ 
MMA - butadiene copolymer 
16 
"2M-36" (Trademark), 
made by Takeda Chemical 
Industries, Ltd. 
(Solid content: 47.5%) 
Styrene - acrylic copolymer 
19 
"Polysol 4T-2040" 
(Trademark), made by 
Showa Highpolymer Co., Ltd. 
(Solid content: 40%) 
Terpene resin (m. p. 120.degree. C.) 
10 
Dicyclohexyl phthalate 
25 
Amine-based dispersant 
2 
Water 28 
______________________________________ 
On the above prepared barrier layer, the thermosensitive adhesive layer 
coating liquid was coated and dried in such a fashion that the deposition 
amount of the coating liquid was 20 g/m.sup.2 on a dry basis. 
Thus, a thermosensitive adhesive layer was provided on the barrier layer. 
Further, the surface of the thermosensitive adhesive layer was subjected to 
a supercalendering treatment once at a calendering speed of 15 m/min with 
the application of a load of 10 kg thereto so as to have a smoothness of 
600 sec in terms of Bekk's smoothness. 
Thus, a thermosensitive recording adhesive label No. 1 according to the 
present invention was obtained. 
EXAMPLE 2 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the thermosensitive 
adhesive layer was subjected to a supercalendering treatment once at a 
calendering speed of 15 m/min with the application of a load of 20 kg 
thereto so as to have a smoothness of 2,500 sec in terms of Bekk's 
smoothness. 
Thus, a thermosensitive recording adhesive label No. 2 according to the 
present invention was obtained. 
EXAMPLE 3 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the thermosensitive 
adhesive layer was subjected to a supercalendering treatment once at a 
calendering speed of 50 m/min with no load being applied thereto so as to 
have a smoothness of 80 sec in terms of Bekk's smoothness. 
Thus, a thermosensitive recording adhesive label No. 3 according to the 
present invention was obtained. 
EXAMPLE 4 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the thermosensitive 
coloring layer was subjected to a supercalendering treatment once at a 
calendering speed of 15 m/min with the application of a load of 10 kg 
thereto so as to have a smoothness of 500 sec in accordance with the 
method of Ohken-shiki prescribed in Japan Tappi No. 5. 
Thus, a thermosensitive recording adhesive label No. 4 according to the 
present invention was obtained. 
EXAMPLE 5 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the water content in the 
obtained thermosensitive recording adhesive label was slightly increased 
by adjusting the drying conditions so as to have a surface smoothness of 
the thermosensitive coloring layer of 8,000 sec in accordance with the 
method of Ohken-shiki prescribed in Japan Tappi No. 5. 
Thus, a thermosensitive recording adhesive label No. 5 according to the 
present invention was obtained. 
EXAMPLE 6 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the coating liquid for 
the formation of the barrier layer in Example 1 was replaced by a Liquid E 
with the following formulation, and that the deposition amount of the thus 
prepared barrier layer coating liquid E was changed from 3 g/m.sup.2 to 
2.5 g/m.sup.2 on a dry basis, and the air permeability of the obtained 
barrier layer was controlled to 8,000 sec. 
______________________________________ 
Parts by Weight 
______________________________________ 
Liquid E! 
10% aqueous solution of 
9 
polyvinyl alcohol 
10% aqueous solution of 
3 
polyamide epichlorohydrin 
Aluminum hydroxide 
30 
Water 58 
______________________________________ 
Thus, a thermosensitive recording adhesive label No. 6 according to the 
present invention was obtained. 
EXAMPLE 7 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the barrier layer as 
employed in Example 1 was not provided on the back side of the support, so 
that a thermosensitive recording adhesive label No. 7 according to the 
present invention was obtained. 
EXAMPLE 8 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the non-expandable 
insulating layer as employed in Example 1 was not provided on the support, 
so that a thermosensitive recording adhesive label No. 8 according to the 
present invention was obtained. 
EXAMPLE 9 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the MMA-butadiene 
copolymer in an amount of 16 parts by weight used in the formulation for 
the thermosensitive adhesive layer coating liquid in Example 1 was 
replaced by the styrene-acrylic copolymer "Polysol 4T-2040" (Trademark), 
made by Showa Highpolymer Co., Ltd., so that a thermosensitive recording 
adhesive label No. 9 according to the present invention was obtained. 
Comparative Example 1 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the thermosensitive 
adhesive layer was not subjected to a supercalendering treatment so as to 
have a smoothness of 30 sec in terms of Bekk's smoothness. 
Thus, a comparative thermosensitive recording adhesive label No. 1 was 
obtained. 
Comparative Example 2 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the thermosensitive 
adhesive layer was subjected to a supercalendering treatment once at a 
calendering speed of 15 m/min with the application of a load of 30 kg 
thereto so as to have a smoothness of 3,500 sec in terms of Bekk's 
smoothness. 
Thus, a comparative thermosensitive recording adhesive label No. 2 was 
obtained. 
Comparative Example 3 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the water content of the 
obtained thermosensitive recording adhesive label was rather increased by 
adjusting the drying conditions so as to have a surface smoothness of the 
thermosensitive coloring layer of 15,000 sec in accordance with the method 
of Ohken-shiki prescribed in Japan Tappi No. 5. 
Thus, a comparative thermosensitive recording adhesive label No. 3 was 
obtained. 
Comparative Example 4 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 8 in Example 8 was repeated except that the thermosensitive 
coloring layer was subjected to a supercalendering treatment once at a 
calendering speed of 15 m/min with no load being applied thereto so as to 
have a smoothness of 150 sec in accordance with the method of Ohken-shiki 
prescribed in Japan Tappi No. 5. 
Thus, a comparative thermosensitive recording adhesive label No. 4 was 
obtained. 
EXAMPLE 10 
Preparation of Thermosensitive Recording Adhesive Label 
Formation of insulating layer 
The following components were stirred and dispersed, so that a coating 
liquid for a non-expandable insulating layer was prepared: 
______________________________________ 
Parts by Weight 
______________________________________ 
Aqueous dispersion of minute 
30 
void particles (copolymer resin 
comprising vinylidene chloride and 
acrylonitrile as the main components) 
(Solid content: 32%, average 
particle diameter: 5 .mu.m, 
and voidage: 92%) 
Styrene - butadiene copolymer latex 
10 
Water 60 
______________________________________ 
The thus prepared insulating layer coating liquid was coated on a sheet of 
high quality paper with a basis weight of 80 g/m.sup.2 serving as a 
support, and dried in such a fashion that the deposition amount of the 
coating liquid was 5 g/m.sup.2 on a dry basis. Thus, a non-expandable 
insulating layer was provided on the support. 
Formation of thermosensitive coloring layer 
A mixture of the following components was separately dispersed and 
pulverized in a sand mill until the average particle size reached 2.0 
.mu.m or less, thereby obtaining a Liquid F and a Liquid G: 
______________________________________ 
Parts by Weight 
______________________________________ 
Liquid F! 
3-dibenzylamino-6-methyl- 
20 
7-anilinofluoran 
10% aqueous solution of 
20 
polyvinyl alcohol 
Water 60 
Liquid G! 
4,4'-dihydroxybenzophenone 
10 
10% aqueous solution of 
25 
polyvinyl alcohol 
Calcium carbonate 15 
Water 50 
______________________________________ 
One part by weigh of the Liquid F and eight parts by weight of the Liquid G 
were mixed and stirred, so that a thermosensitive coloring layer coating 
liquid H was prepared. 
On the above obtained insulating layer, the thermosensitive coloring layer 
coating liquid H was coated and dried in such a fashion that the 
deposition amount of the coating liquid was 5 g/m.sup.2 on a dry basis. 
Then, the surface of the coated layer was subjected to a supercalendering 
treatment once at a calendering speed of 15 m/min with the application of 
a load of 20 kg thereto so as to have a smoothness of 700 sec in 
accordance with the method of Ohken-shiki prescribed in Japan Tappi No. 5. 
Formation of barrier layer 
A mixture of the following components was stirred and dispersed, so that a 
barrier layer coating liquid was prepared: 
______________________________________ 
Parts by Weight 
______________________________________ 
10% aqueous solution of 
50 
polyvinyl alcohol 
Aluminum hydroxide 
5 
10% aqueous solution of 
20 
polyamide epichlorohydrin 
Water 25 
______________________________________ 
On the back side of the support, opposite to the side of the 
thermosensitive coloring layer with respect to the support, the barrier 
layer coating liquid was coated and dried in such a fashion that the 
deposition amount of the coating liquid was 3 g/m.sup.2 on a dry basis. 
Thus, a barrier layer was provided on the back side of the support. In this 
case, the air permeability of the obtained barrier layer was infinity 
(.infin.). 
Formation of Thermosensitive Adhesive Layer 
A mixture of the following components was dispersed in a ball mill until 
the particle diameter reached 3.0 .mu.m or less, so that a thermosensitive 
adhesive layer coating liquid was prepared: 
______________________________________ 
Parts by Weight 
______________________________________ 
MMA - butadiene copolymer 
16 
"2M-36" (Trademark), 
made by Takeda Chemical 
Industries, Ltd. 
(Solid content: 47.5%) 
Styrene - acrylic copolymer 
19 
"Polysol 4T-2040" 
(Trademark), made by 
Showa Highpolymer Co., Ltd. 
(Solid content: 40%) 
Terpene resin (m. p. 120.degree. C.) 
10 
Dicyclohexyl phthalate 
25 
Amine-based dispersant 
2 
Water 28 
______________________________________ 
On the above prepared barrier layer, the thermosensitive adhesive layer 
coating liquid was coated and dried in such a fashion that the deposition 
amount of the coating liquid was 20 g/m.sup.2 on a dry basis. 
Thus, a thermosensitive adhesive layer was provided on the barrier layer. 
Further, the surface of the thermosensitive adhesive layer was subjected 
to a supercalendering treatment once at a calendering speed of 15 m/min 
with the application of a load of 10 kg thereto so as to have a smoothness 
of 600 sec in terms of Bekk's smoothness. 
Thus, a thermosensitive recording adhesive label No. 10 according to the 
present invention was obtained. 
EXAMPLE 11 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that the coating liquid for 
the formation of the barrier layer in Example 1 was replaced by a Liquid I 
with the following formulation, and that the air permeability of the 
barrier layer was controlled to 15,000 sec. 
______________________________________ 
Parts by Weight 
______________________________________ 
Liquid I! 
Silica 10 
10% aqueous solution of 
50 
polyvinyl alcohol 
Water 40 
______________________________________ 
Thus, a thermosensitive recording adhesive label No. 11 according to the 
present invention was obtained. 
EXAMPLE 12 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that an insulating layer was 
further provided between the high quality paper serving as the support and 
the barrier layer by coating on the back side of the paper the same 
coating liquid as used for the formation of the insulating layer in 
Example 1, and drying the same. 
In this case, the thermosensitive coloring layer was subjected to a 
supercalendering treatment twice at a calendering speed of 15 m/min with 
the application of a load of 30 kg thereto so as to have a smoothness of 
2,000 sec when measured by the method of Ohken-shiki. The thermosensitive 
adhesive layer was subjected to a supercalendering treatment once at a 
calendering speed of 50 m/min with no load being applied thereto so as to 
have a smoothness of 80 sec in terms of Bekk's smoothness. 
EXAMPLE 13 
The procedure for preparation of the thermosensitive recording adhesive 
label No. 1 in Example 1 was repeated except that a barrier layer was 
further provided between the high quality paper serving as the support and 
the insulating layer by coating the same coating liquid as used for the 
formation of the barrier layer in Example 1 on the paper and drying the 
same. 
In this case, the thermosensitive coloring layer was subjected to a 
supercalendering treatment twice at a calendering speed of 15 m/min with 
the application of a load of 30 kg thereto so as to have a smoothness of 
2,000 sec when measured by the method of Ohken-shiki. The thermosensitive 
adhesive layer was subjected to a supercalendering treatment twice at a 
calendering speed of 15 m/min with the application of a load of 10 kg 
thereto so as to have a smoothness of 600 sec in terms of Bekk's 
smoothness. 
Each of the thermosensitive recording adhesive labels No. 1 to No. 13 in 
Examples 1 to 13 and comparative thermosensitive recording adhesive labels 
No. 1 to No. 4 in Comparative Examples 1 to 4 was evaluated with respect 
to the following aspects: 
(1) Dynamic coloring density of thermosensitive coloring layer 
Each thermosensitive recording adhesive label was loaded in a 
thermosensitive printing test apparatus equipped with a commercially 
available thin film head (made by Matsushita Electronic Components Co., 
Ltd.), and images were thermally printed on the thermosensitive recording 
label under the conditions that the applied electric power was 0.45 W/dot, 
the period for one line was 4 msec/line and the scanning density was 
8.times.7.7 dot/mm, with the pulse width changed to 0.4 msec and 0.5 msec. 
The coloring density of the images recorded on the thermosensitive 
recording label was measured using a McBeth densitometer RD-914. 
The results are shown in Table 1. 
(2) Adhesiveness of thermosensitive adhesive layer by heat activation 
The thermosensitive adhesive layer was activated in such a manner that the 
thermosensitive adhesive layer was exposed to a halogen lamp of 1350 W at 
an irradiation speed of 3 inch/sec, using a commercially available 
apparatus, "Transparency-Maker" (Trademark), made by Sumitomo 3M Limited. 
The thus heat-activated thermosensitive adhesive layer of each adhesive 
label was attached to a vinyl chloride wrap. Then, the adhesiveness of the 
thermosensitive adhesive layer to the vinyl chloride wrap was evaluated on 
the following scale: 
A: The adhesiveness was very strong and considered to be preferable in 
practical use. 
B: The adhesiveness was sufficient and the thermosensitive recording 
adhesive label was acceptable in practical use. 
C: The adhesiveness was weak, and the thermosensitive recording adhesive 
label was not acceptable in practical use. 
The results are shown in Table 1. 
(3) Blocking resistance 
A couple of thermosensitive recording adhesive label samples were attached 
to each other in such a fashion that the thermosensitive adhesive layer of 
one sample was brought into contact with the thermosensitive coloring 
layer of the other sample. Those samples were allowed to stand at 
40.degree. C. and 90% RH under the application of a load of 2 kg/cm.sup.2 
for 24 hours. 
24 hours later, the one sample was peeled from the other sample at room 
temperature, and the blocking resistance of the thermosensitive recording 
adhesive label after storage was evaluated on the following scale: 
A: The blocking phenomenon was not recognized because there was no peeling 
sound. 
B: The blocking phenomenon was not serious although there was a faint 
peeling sound. 
C: The blocking phenomenon was partially recognized by the peeling sound. 
The results are shown in Table 1. 
(4) Plasticizer resistance 
Images were thermally printed on each thermosensitive recording adhesive 
label using the above-mentioned thermosensitive printing test apparatus 
equipped with a commercially available thin film head (made by Matsushita 
Electronic Components Co., Ltd.) with the pulse width being set to 1.2 
msec. Then, the thermosensitive adhesive layer was exposed to a halogen 
lamp with a power of 1350 W, using the commercially available apparatus 
"Transparency Maker" (Trademark), made by Sumitomo 3M Limited., to 
activate the thermosensitive adhesive layer. 
The thus prepared thermosensitive recording adhesive label was attached to 
three laminated vinyl chloride wraps, "Polymer Wrap 300" (Trademark), made 
by Shin-Etsu Polymer Co., Ltd. The label was allowed to stand at 
50.degree. C. under the application of a load of 5 kg thereto for 48 
hours. Thereafter, the image density of the images printed on the label 
was measured using a McBeth densitometer RD-914. 
The results are shown in Table 1. 
TABLE 1 
__________________________________________________________________________ 
Air 
permeability 
Adhesiveness 
Dynamic 
Surface Smoothness (sec.) (*) 
of Barrier 
(to vinyl 
Coloring 
Thermosensitive 
Thermosensitive 
Layer (sec.) 
chloride 
Density Plasticizer 
Blocking 
coloring layer 
adhesive layer 
(**) wrap) 0.4 ms 
0.5 ms 
Resistance 
Resistance 
__________________________________________________________________________ 
Ex. 1 
2000 600 .infin. 
A 0.81 
1.21 
1.37 A 
Ex. 2 
2000 2500 .infin. 
A 0.82 
1.22 
1.36 B 
Ex. 3 
2000 80 .infin. 
B 0.81 
1.22 
1.37 A 
Ex. 4 
500 600 .infin. 
A 0.78 
1.19 
1.35 A 
Ex. 5 
8000 600 .infin. 
A 0.84 
1.24 
1.38 B 
Ex. 6 
2000 600 8000 A 0.82 
1.21 
0.58 A 
Ex. 7 
2000 600 (-) A 0.81 
1.22 
0.31 A 
Ex. 8 
2000 600 .infin. 
A 0.64 
1.04 
1.35 A 
Ex. 9 
2000 600 .infin. 
A 0.81 
1.21 
1.36 A 
Comp. 
2000 &lt;30 .infin. 
C 0.81 
1.22 
1.37 A 
Ex. 1 
Comp. 
2000 &gt;3500 .infin. 
A 0.82 
1.22 
1.36 C 
Ex. 2 
Comp. 
&gt;15000 600 .infin. 
A 0.85 
1.25 
1.38 C 
Ex. 3 
Comp. 
&lt;150 600 .infin. 
A 0.37 
0.87 
1.35 A 
Ex. 4 
Ex. 10 
700 600 .infin. 
A 0.62 
1.03 
1.37 A 
Ex. 11 
2000 600 15000 A 0.80 
1.21 
1.36 A 
Ex. 12 
2000 80 .infin. 
A 0.63 
1.04 
1.36 A 
Ex. 13 
2000 600 .infin. 
A 0.83 
1.24 
1.37 A 
__________________________________________________________________________ 
(*) The surface smoothness is not always the same under the same 
calendering conditions because it varies depending on the water content o 
the obtained label and the kind of calendering apparatus to be employed. 
(**) The air permeability of the barrier layer is measured by the method 
of Ohkenshiki prescribed in Japan Tappi No. 5. 
As can be seen from the results shown in Table 1, when the thermosensitive 
recording adhesive label according to the present invention is employed, 
the adhesiveness of the thermosensitive adhesive layer to the adherend 
surface such as a polyvinyl wrap is satisfactory, the coloring density of 
images thermally printed on the thermosensitive recording label is 
sufficient. Furthermore, the blocking resistance and the plasticizer 
resistance are also excellent during the storage in the roll form. 
Japanese Patent Application No. 8-099148 filed Mar. 28, 1996, Japanese 
Patent Application No. 8-099149 filed Mar. 28, 1996, Japanese Patent 
Application No. 8-099150 filed Mar. 28, 1996, Japanese Patent Application 
No. 8-099151 filed Mar. 28, 1996, and Japanese Patent Application No. 
8-154969 filed May 27, 1996 are hereby incorporated by reference.