Salicylic acid derivatives, the process for preparing the same and the heat-sensitive recording materials comprising thereof

A heat-sensitive recording material comprising a color forming, electron donating compound and a salicylic acid derivative represented by the formula (1): ##STR1## wherein X.sub.1 and X.sub.2 are a hydrogen atom, an alkyl group, an alkoxy group, an aralkyl group, an aryl group or a halogen atom, Y.sub.1 and Y.sub.2 are an oxygen atom or a sulfur atom, R.sub.1 is a hydrogen atom, an alkyl group, an aralkyl group or an aryl group , and R.sub.2 is an alkyl group, an alkenyl group, an aralkyl group or an aryl group, and/or a metal salt of the salicylic acid derivative as an electron accepting compound, is disclosed.

BACKGROUND OF THE INVENTION 
1. Field of the Invention 
The present invention relates to a heat-sensitive recording material and 
particularly relates to a heat-sensitive recording material having 
improved storage stability of an uncolored portion and a developed color 
image. Further, the invention relates to metal salts of salicylic acid 
derivatives which are useful as an electron accepting compound in the 
heat-sensitive recording material and a process for preparing said 
salicylic acid derivatives and metal salts of the same. 
2. Related Art of the Invention 
Heat-sensitive recording materials which utilize color forming reaction of 
electron donating compounds with electron accepting compounds(developer) 
have conventionally been well known, for example, in Japanese Patent 
Publication Sho 43-4160 and 45-14039. 
Heat-sensitive recording materials are relatively inexpensive and 
advantageous in that recording equipment is compact and free from 
maintenance, and hence have widely been used in the field of a facsimile, 
recorder and printer. 
Recently, use field of heat-sensitive recording materials has been further 
extended and diversified to uses under severe environment, for example, 
labels and pre-paid cards. 
However, conventionally known heat-sensitive recording materials which 
employ 2,2-bis(4'-hydroxyphenyl)propane(bisphenol A) or benzyl 
4-hydroxybenzoate as an electron accepting compound have such a 
disadvantage that remarkable soiling of an uncolored portion or fading of 
a developed color image occurs in the severe environment, for example, in 
contact with oils, solvents, fats and writing utensils such as a 
fluorescent pen or in moist environment. 
In order to improve these disadvantages, heat-sensitive recording materials 
which contain salicylic acid derivatives having substituted amino groups 
or metal salts thereof as electron accepting compounds have been proposed 
(Japanese Laid-Open Patent Sho 63-95979). 
However, the heat-sensitive recording material which uses 
4-phenylacetylaminosalicylic acid or a metal salt such as zinc salt of the 
same which described in the patent as an electron accepting compound is 
still poor in the storage stability of a developed color image against 
moist heat, has low sensitivity for color development and cannot conform 
to practical high-speed recording. The heat-sensitive recording material 
obtained as described in the patent by using 4-benzoylaminosalicylic acid 
and metal salts(for example, zinc salt) thereof as an electron accepting 
compound has also poor storage stability, for example, moist heat 
resistance of a developed color image and a disadvantage of low developing 
sensitivity. Further, the heat-sensitive recording material obtained by 
using a similar compound 4-n-octylcarbonylaminosalicylic acid or its metal 
salts such as zinc salt as an electron accepting compound has also the 
same disadvantages as above. On the basis of such circumstances, it has 
been strongly desired to develop a heat-sensitive recording material 
having good developing sensitivity and further improved storage stability 
of the uncolored portion and developed color image. 
Relatively many salicylic acid derivatives having an amino group have been 
known to be used for heat-sensitive recording materials as disclosed 
above. 
The salicylic acid derivative which is disclosed in the invention has a 
carbamate group as a substituent and is represented by the formula (1). 
Some of the salicylic acid derivative represented by the formula (1) have 
already been prepared, for example, in German Patent 2749518, Bull. de 
Socie. Chim. France, 1189 (1955), and J. Pharm. Sci., 52, 927 (1963). The 
sodium salt of the salicylic acid derivative is the only metal salt which 
has been disclosed and no disclosure has been found at all on divalent, 
trivalent and tetravalent metal salts. As to the application to the 
heat-sensitive recording material, no disclosure has been found on the 
salicylic acid derivative having the carbamate group as a substituent or a 
metal salt of the derivative. 
The above German Patent 2749518 has disclosed a preparation process of 
4-benzyloxycarbonylaminosalicylic acid and 
5-benzyloxycarbonylaminosalicylic acid by individually reacting 
4-aminosalicylic acid and 5-aminosalicylic acid with benzylchloroformate 
in dry pyridine. However, the yield is very low. For example, the yield of 
5-benzyloxycarbonylaminosalicylic acid in the process is about 25%. 
In the preparation process described in Bull. de Socie. Chim. France, 1189 
(1955), 4-alkyloxycarbonylaminosalicylic acid is obtained by reacting an 
aqueous sodium 4-aminosalicylate solution with alkylchloroformate. 
However, the yield is not satisfactory in the process. For example, the 
yield of 4-n-pentyloxycarbonylaminosalicylic acid is about 70%. 
In the preparation process described in J. Pharm. Sci., 52, 927 (1963), 
4-aminosalicylic acid and 5-aminosalicylic acid is reacted with 
phenylchloroformate in an aqueous sodium hydrogen carbonate solution to 
obtain 4-phenyloxycarbonylaminosalicylic acid and 
5-phenyloxycarbonylaminosalicylic acid, respectively, in the relatively 
high yield. 
However, the present inventors have found that, when 4-aminosalicylic acid 
or 5-aminosalicylic acid is reacted in an aqueous sodium hydrogen 
carbonate solution with various chloroformate compounds, particularly 
alkylchloroformate compounds having more than 5 carbon atoms, the yield of 
desired 4-carbamate substituted salicylic acid derivative or 5-carbamate 
substituted salicylic acid derivative is very low (50% or less). 
Consequently, it has been strongly desired to develop a simple and broadly 
applicable process for preparing a carbamate substituted salicylic acid 
derivative in high purity. 
OBJECTS OF THE INVENTION 
The object of the invention is to provide a heat-sensitive recording 
material having remarkably improved storage stability of an uncolored 
portion and a developed color image. 
The second object of the invention is to provide a divalent, trivalent or 
tetravalent metal salt of a salicylic acid derivative which is useful as 
an electron accepting compound of said heat-sensitive recording material. 
The third object of the invention is to provide a process for preparing the 
salicylic acid derivative and the metal salt of the derivative. 
In order to achieve the above objects, the present inventors have carried 
out an intensive investigation on the heat-sensitive recording material, 
the electron accepting compound in particular, and completed the 
invention. 
SUMMARY OF THE INVENTION 
The present invention is a heat-sensitive recording material comprising a 
color forming, electron donating compound and an electron accepting 
compound wherein said electron accepting compound is one or more compound 
selected from a salicylic acid derivative represented by the formula (1): 
##STR2## 
wherein X.sub.1 and X.sub.2 each are a hydrogen atom, an alkyl group, an 
alkoxy group, an aralkyl group, an aryl group or a halogen atom, Y.sub.1 
and Y.sub.2 each are an oxygen or a sulfur atom, R.sub.1 is a hydrogen 
atom, an alkyl group, an aralkyl group or an aryl group, and R.sub.2 is an 
alkyl group, an alkenyl group, an aralkyl group or an aryl group, and/or a 
metal salt of said salicylic acid derivative; a divalent, trivalent or 
tetravalent metal salt of the salicylic acid derivative represented by the 
formula (1); a process for preparing the salicylic acid derivative 
represented by the formula (1) by reacting a compound represented by the 
formula (2): 
##STR3## 
wherein X, and X.sub.2 are a hydrogen atom, an alkyl group, an alkoxy 
group, an aralkyl group, an aryl group or a halogen atom, and R.sub.1 is a 
hydrogen atom, an alkyl group, an aralkyl group or an aryl group, with a 
compound represented by the formula (3): 
##STR4## 
wherein Y.sub.1 and Y.sub.2 are an oxygen atom or a sulfur atom, R.sub.2 
is an alkyl group, an alkenyl group, an aralkyl group or an aryl group, 
and Z is a halogen atom, in the presence of an alcohol-based solvent; and 
a process for preparing a multivalent metal salt of salicylic acid 
derivative by reacting said salicylic acid derivative with a salt of from 
divalent to tetravalent metal. 
The invention provides a heat-sensitive recording material whose uncolored 
portions have excellent storage stability and a developed color image and 
has enhanced developing sensitivity.

DETAILED DESCRIPTION OF THE INVENTION 
The present invention is a heat-sensitive recording material comprising a 
color forming, electron donating compound and an electron accepting 
compound wherein said electron accepting compound is a salicylic acid 
derivative represented by the formula (1) and/or a metal salt of the 
salicylic acid derivative. 
The salicylic acid derivative and the metal salt of the derivative which 
can be used in the invention have following atoms and groups in the 
formula (1). 
X.sub.1 and X.sub.2 are a hydrogen or halogen atom, an alkyl, alkoxy, 
aralkyl or aryl group, preferably hydrogen, C.sub.1 .about.C.sub.20 alkyl, 
C.sub.5 .about.C.sub.14 alicyclic, C.sub.1 .about.C.sub.20 alkoxy, C.sub.7 
.about.C.sub.20 aralkyl, phenyl, fluorine, chlorine or bromine, more 
preferably hydrogen, C.sub.1 .about.C.sub.4 alkyl, cyclohexyl, C.sub.1 
.about.C.sub.4 alkoxy, benzyl, .alpha.-methylbenzyl, cumyl, phenyl or 
chlorine, and most preferably hydrogen. 
Y.sub.1 and Y.sub.2 are a oxygen or sulfur atom, and preferably Y.sub.1 is 
oxygen. 
R.sub.1 is a hydrogen atom, an alkyl, aralkyl or aryl group, preferably 
hydrogen, C.sub.1 .about.C.sub.20 alkyl, C.sub.5 .about.C.sub.14 
alicyclic, C.sub.7 .about.C.sub.20 aralkyl, phenyl or substituted phenyl, 
more preferably hydrogen, C.sub.1 .about.C.sub.8 alkyl, cyclopentyl, 
cyclohexyl, cycloheptyl, benzyl or phenyl, further preferably hydrogen, 
C.sub.1 .about.C.sub.4 alkyl or phenyl, and most preferably hydrogen. 
R.sub.2 is an alkyl, alkenyl, aralkyl or aryl group, preferably alkyl or 
substituted alkyl, alicyclic or substituted alicyclic, alkenyl or 
substituted alkenyl, cyclic alkenyl or substituted cyclic alkenyl, aralkyl 
or substituted aralkyl, phenyl or substituted phenyl, naphthyl or 
substituted naphthyl, or heteroaromatic or substituted heteroaromatic. 
The alkyl or alkenyl represented by R.sub.2 can be monosubstituted or 
polysubstituted. 
The substituents include, for example, C.sub.1 .about.C.sub.20 alkoxy, 
C.sub.2 .about.C.sub.20 alkoxyalkyloxy, C.sub.2 .about.C.sub.20 
alkenyloxy, C.sub.7 .about.C.sub.20 aralkyloxy, C.sub.8 .about.C.sub.20 
aralkyloxyalkoxy, C.sub.6 .about.C.sub.20 aryloxy, C.sub.7 .about.C.sub.20 
aryloxyalkoxy, C.sub.8 .about.C.sub.20 arylalkenyl, C.sub.9 
.about.C.sub.20 aralkylalkenyl, C.sub.1 .about.C.sub.20 alkylthio, C.sub.2 
.about.C.sub.20 alkoxyalkylthio, C.sub.2 .about.C.sub.20 
alkylthioalkylthio, C.sub.2 .about.C.sub.20 alkenylthio, C.sub.7 
.about.C.sub.20 aralkylthio, C.sub.8 .about.C.sub.20 aralkyloxyalkylthio, 
C.sub.8 .about.C.sub.20 aralkylthioalkylthio, C.sub.6 .about.C.sub.20 
arylthio, C.sub.7 .about.C.sub.20 aryloxyalkylthio, C.sub.7 
.about.C.sub.20 arylthioalkylthio, hetroalicyclic and halogen. 
Further, aryl which is included in these substituents can be substituted 
with C.sub.1 .about.C.sub.6 alkyl, C.sub.1 .about.C.sub.6 alkoxy, C.sub.1 
.about.C.sub.6 alkylthio, C.sub.7 .about.C.sub.10 aralkyl, C.sub.7 
.about.C.sub.10 aralkyloxy, hydroxyl or halogen. 
The aralkyl or aryl represented by R.sub.2 can be monosubstituted or 
polysubstituted. 
Exemplary substituents include, C.sub.1 .about.C.sub.20 alkyl, C.sub.2 
.about.C.sub.20 alkenyl, C.sub.7 .about.C.sub.20 aralkyl, C.sub.6 
.about.C.sub.20 aryl, C.sub.1 .about.C.sub.20 alkoxy, C.sub.2 
.about.C.sub.20 alkoxyalkyl, C.sub.2 .about.C.sub.20 alkoxyalkyloxy, 
C.sub.2 .about.C.sub.20 alkenyloxy, C.sub.3 .about.C.sub.20 
alkenyloxyalkyl, C.sub.3 .about.C.sub.20 alkenyloxyalkyloxy, C.sub.7 
.about.C.sub.20 aralkyloxy, C.sub.8 .about.C.sub.20 aralkyloxyalkyl, 
C.sub.8 .about.C.sub.20 aralkyloxyalkyloxy, C.sub.6 .about.C.sub.20 
aryloxy, C.sub.7 .about.C.sub.20 aryloxyalkyl, C.sub.7 .about.C.sub.20 
aryloxyalkyloxy, C.sub.2 .about.C.sub.20 alkylcarbonyl, C.sub.3 
.about.C.sub.20 alkenylcarbonyl, C.sub.8 .about.C.sub.20 aralkylcarbonyl, 
C.sub.7 .about.C.sub.20 arylcarbonyl, C.sub.2 .about.C.sub.20 
alkoxycarbonyl, C.sub.3 .about.C.sub.20 alkenyloxycarbonyl, C.sub.8 
.about.C.sub.20 aralkyloxycarbonyl, C.sub.7 .about.C.sub.20 
aryloxycarbonyl, C.sub.2 .about.C.sub.20 alkylcarbonyloxy, C.sub.3 
.about.C.sub.20 alkenylcarbonyloxy, C.sub.8 .about.C.sub.20 
aralkylcarbonyloxy, C.sub.7 .about.C.sub.20 arylcarbonyloxy, C.sub.14 
.about.C.sub.20 aralkyloxyaralkyl, C.sub.1 .about.C.sub.20 alkylthio, 
C.sub.7 .about.C.sub.20 aralkylthio, C.sub.6 .about.C.sub.20 arylthio, 
nitro, formyl, halogen, hydroxy and cyano. 
Aryl which is present in these substituents can be further substituted with 
C.sub.1 .about.C.sub.6 alkyl, C.sub.1 .about.C.sub.6 alkoxy, C.sub.1 
.about.C.sub.6 alkylthio, C.sub.7 .about.C.sub.10 aralkyl, C.sub.7 
.about.C.sub.10 aralkyloxy, hydroxy or halogen. 
Preferred R.sub.2 is unsubstituted or substituted alkyl having from 1 to 24 
total carbon atoms, unsubstituted or substituted alkenyl having from 2 to 
24 total carbon atoms, unsubstituted or substituted aralkyl having from 7 
to 24 total carbon atoms, or unsubstituted or substituted aryl having from 
6 to 24 total carbon atoms. 
Exemplary R.sub.2 include methyl, ethyl, n-propyl, isopropyl, n-butyl, 
isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, n-hexyl, 
1-methylpentyl, 4-methyl-2-pentyl, n-heptyl, 1-methylhexyl, n-octyl, 
1-methylheptyl, 2-ethylhexyl, n-nonyl, 2,6-dimethyl-4-heptyl, 
3,5,5-trimethylhexyl, n-decyl, 1-ethyloctyl, n-undecyl, 1-methyldecyl, 
n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-hexadecyl, 
n-heptadecyl, n-octadecyl, cyclopentyl, cyclohexyl, 4-methylcyclohexyl, 
3-methylcyclohexyl, 2-methylcyclohexyl, 2,5-dimethylcyclohexyl, 
2,6-dimethylcyclohexyl, 3,4-dimethylcyclohexyl, 3,5-dimethylcyclohexyl, 
3,3,5-trimethylcyclohexyl, 4-tert-butylcyclohexyl, 3-tert-butylcyclohexyl, 
4-phenylcyclohexyl, 2-phenylcyclohexyl, cycloheptyl, cyclooctyl, 
clyclohexylmethyl, 2-cyclohexylethyl, bornyl, isobornyl, 
2-norbornylmethyl, 1-adamantylmethyl, vinyl, allyl, 2-butenyl, 3-butenyl, 
1-methyl-4-pentenyl, 2-pentenyl, 4-pentenyl, 1-methyl-2-butenyl, 
2-hexenyl, 3-hexenyl, 4-hexenyl, 5-hexenyl, 2-heptenyl, 1-vinylhexyl, 
3-nonenyl, 6-nonenyl, 9-decenyl, 10-undecenyl, 1-cyclohexenyl, 
2-methoxyethyl, 2-ethoxyethyl, 2-isopropoxyethyl, 2-n-butoxyethyl, 
2-n-pentyloxyethyl, 2-heptyloxyethyl, 2-n-hexyloxyethyl, 
2-n-octyloxyethyl, 2-n-decyloxyethyl, 2-n-dodecyloxyethyl, 
2-cyclohexyloxyethyl, 3-n-methoxypropyl, 3-ethoxypropyl, 
3-n-propoxypropyl, 3-n-butoxypropyl, 3-n-hexyloxypropyl, 
3-n-octyloxypropyl, 3-cyclohexyloxypropyl, 4-ethoxybutyl, 5-methoxypentyl, 
6-ethoxyhexyl, 2-methoxyethoxyethyl, 2-ethoxyethoxyethyl, 
2-n-butoxyethoxyethyl, 3-ethoxyethoxypropyl, 2-allyloxyethyl, 
2-(4'-pentenyl)oxyethyl, 3-allyloxypropyl, 4-allyloxybutyl, 
2-benzyloxyethyl, 2-phenethyloxyethyl, 2-(4'-methylbenzyloxy)ethyl, 
2-(4'-chlorobenzyloxy)ethyl, 3-benzyloxypropyl, 4-benzyloxybutyl, 
2-benzyloxymethoxyethyl, 2 -(4'-methylbenzyl)oxymethoxyethyl, 
phenoxymethyl, 2-phenoxyethyl, 2-(4'-chlorophenyloxy)ethyl, 
2-(4'-methylphenyloxy)ethyl, 2-(4'-methoxyphenyloxy)ethyl, 
3-phenoxypropyl, 4-phenoxybutyl, 6-(2'-chlorophenyloxy)hexyl, 
2-phenoxyethoxyethyl, 2-(1'-naphthyloxy)ethyl, 2-(2'-naphthyloxy)ethyl, 
3-(2'-naphthyloxy)propyl, cinnamyl, 2-methylthioethyl, 2-ethylthioethyl, 
2-n-butylthioethyl, 2-n-hexylthioethyl, 2-n-octylthioethyl, 
2-n-decylthioethyl, 3-methylthiopropyl, 3-ethylthiopropyl, 
3-n-butylthiopropyl, 4-ethylthiobutyl, 4-n-propylthiobutyl, 
4-n-butylthiobutyl, 5-ethylthiopentyl, 6-methylthiohexyl, 
6-ethylthiohexyl, 6-n-butylthiohexyl, 8-methylthiooctyl, 
2-methoxyethylthioethyl, 2-ethylthioethylthioethyl, 2-allylthioethyl, 
2-benzylthioethyl, 3-(4'-methylbenzylthio)propyl, 4-benzylthiobutyl, 
2-benzyloxyethylthioethyl, 3-benzylthiopropylthiopropyl, 
2-phenylthioethyl, 2-(4'-methoxyphenylthio)ethyl, 2-phenoxyethylthioethyl, 
3-(2'-chlorophenylthio)ethylthiopropyl, 2-tetrahydrofurfuryl, 
2-chloroethyl, 3-chloropropyl, 2,2,2-trichloroethyl, 7-chloroheptyl, 
8-chlorooctyl, 8-fluorooctyl, benzyl, .alpha.-methylbenzyl, 
.alpha.-ethylbenzyl, phenethyl, .alpha.-methylphenethyl, 
.alpha.,.alpha.-dimethylphenethyl, 4-methylphenethyl, 4-methylbenzyl, 
3-methylbenzyl, 2-methylbenzyl, 4-isopropylbenzyl, 4-allylbenzyl, 
4-benzylbenzyl, 4-phenethylbenzyl, 4-phenylbenzyl, 
4-(4'-methylphenyl)benzyl, 4-methoxybenzyl, 4-n-butoxybenzyl, 
3,4-dimethoxybenzyl, 4-methoxymethylbenzyl, 4-allyloxybenzyl, 
4-vinyloxymethylbenzyl, 4-benzyloxybenzyl, 4-phenethyloxybenzyl, 
4-phenoxybenzyl, 3-phenoxybenzyl, 4-hydroxybenzyl, 3-hydroxybenzyl, 
2-hydroxybenzyl, 4-hydroxy-3-methoxybenzyl, 4-chlorobenzyl, 
3-chlorobenzyl, 2-chlorobenzyl, 2-furfuryl, diphenylmethyl, phenyl, 
1-naphthyl, 2-naphthyl, 3-furyl, 3-thienyl, 4-methylphenyl, 
3-methylphenyl, 2-methylphenyl, 4-ethylphenyl, 3-ethylphenyl, 
2-ethylphenyl, 4-n-propylphenyl, 4-isopropylphenyl, 4-n-butylphenyl, 
4-sec-butylphenyl, 4-tert-butylphenyl, 4-n-pentylphenyl, 
4-isopentylphenyl, 4-n-hexylphenyl, 4-n-heptylphenyl, 4-n-octylphenyl, 
4-tert-octylphenyl, 4-n-decylphenyl, 4-n-dodecylphenyl, 
4-cyclopenthylphenyl, 4-cyclohexylphenyl, 3-cyclohexylphenyl, 
2-cyclohexylphenyl, 4-allylphenyl, 2-allylphenyl, 4-benzylphenyl, 
2-benzylphenyl, 4-cumylphenyl, 4-(4'-methoxycumyl)phenyl, 
4-(4'-benzyloxy)cumylphenyl, 4-(4'-chlorobenzyl)phenyl, 4-phenylphenyl, 
3-phenylphenyl, 2-phenylphenyl, 4-(4'-methoxyphenyl)phenyl, 
2-(2'-methoxyphenyl)phenyl, 4-(4'-chlorophenyl)phenyl, 4-methoxyphenyl, 
3-methoxyphenyl, 2-methoxyphenyl, 4-ethoxyphenyl, 2-ethoxyphenyl, 
3-n-propoxyphenyl, 4-isopropoxyphenyl, 4-n-butoxyphenyl, 
4-isobutoxyphenyl, 4-n-pentyloxyphenyl, 4-isopentyloxyphenyl, 
4-n-hexyloxyphenyl, 4-n-octyloxyphenyl, 4-n-decyloxyphenyl, 
4-n-dodecyloxyphenyl, 4-cyclohexyloxyphenyl, 1-(4-ethylnaphthyl), 
2-(6-butylnaphthyl), 1-(2-methoxynaphthyl), 1-(4-methoxynaphthyl), 
1-(4-n-butoxynaphthyl), 1-(5-ethoxynaphthyl), 2-(6-ethoxynaphthyl), 
2-(6-n-hexyloxynaphthyl), 2-(7-methoxynaphthyl), 2-(7-n-butoxynaphthyl), 
4-methoxymethylphenyl, 4-ethoxymethylphenyl, 4-n-butoxymethylphenyl, 
3-methoxymethylphenyl, 4(2'-methoxyethyl)phenyl, 
4-(2'-ethoxyethyloxy)phenyl, 4 -(2'-n-butoxyethyloxy)phenyl, 
4-(3'-ethoxypropyloxy)phenyl, 4-vinyloxyphenyl, 4-allyloxyphenyl, 
3-allyloxyphenyl, 4-(4'-pentenyloxyphenyl)phenyl, 1-(4-allyloxynaphthyl), 
4-allyloxymethylphenyl, 4-(2'-allyloxyethyloxy)phenyl, 4-benzyloxyphenyl, 
2-benzyloxyphenyl, 4-phenetyloxyphenyl, 4-(4'-chlorobenzyloxy)phenyl, 
4-(4'-methylbenzyloxy)phenyl, 4-(4'-methoxybenzyloxy)phenyl, 
4-(3'-ethoxybenzyloxy)phenyl, 1-(4-benzyloxynaphthyl), 
2-(6-benzyloxynaphthyl), 2-(7-benzyloxynaphthyl), 
4-(benzyloxymethyl)phenyl, 4-(2'-benzyloxyethyloxy)phenyl, 
4-phenoxyphenyl, 3-phenoxyphenyl, 2-phenoxyphenyl, 
4-(4'-methylphenoxy)phenyl, 4-(4'-methoxyphenoxy)phenyl, 
4-(4'-chlorophenoxy)phenyl, 1-(4-phenoxynaphthyl), 4-phenoxymethylphenyl, 
4-(2'-phenoxyethyloxy)phenyl, 4-[2'-(4'-methylphenyl)oxyethyloxy]phenyl, 
4-[2'-(4'-methoxyphenyl)oxyethyloxy]phenyl, 
4-[2'-(4'-chlorophenyl)oxyethyloxy]phenyl, 4-acetylphenyl, 3-acetylphenyl, 
2-acetylphenyl, 4-ethylcarbonylphenyl, 4-n-butylcarbonylphenyl, 
4-n-hexylcarbonylphenyl, 4-n-octylcarbonylphenyl, 
4-cyclohexylcarbonylphenyl, 1-(4-acetylnaphthyl), 4-allylcarbonylphenyl, 
4-benzylcarbonylphenyl, 4-(4'-methylbenzyl)carbonylphenyl, 
4-phenylcarbonylphenyl, 4-(4'-methylphenyl)carbonylphenyl, 
4-(4'-chlorophenyl)carbonylphenyl, 1-(4-phenylcarbonylnaphthyl), 
4-methoxycarbonylphenyl, 2-methoxycarbonylphenyl, 4-ethoxycarbonylphenyl, 
3-ethoxycarbonylphenyl, 4-n-propoxycarbonylphenyl, 
4-n-butoxycarbonylphenyl, 4-n-hexyloxycarbonylphenyl, 
4-n-decyloxycarbonylphenyl, 4-cyclohexyloxycarbonylphenyl, 
1-(4-ethoxycarbonylnaphthyl), 2-(6-methoxycarbonylnaphthyl), 
2-(6-n-butoxycarbonylnaphthyl), 4-allyloxycarbonylphenyl, 
4-benzyloxycarbonylphenyl, 4-(4'-chlorobenzyl)oxycarbonylphenyl, 
4-phenetyloxycarbonylphenyl, 2-(6-benzyloxycarbonylnaphthyl), 
4-phenyloxycarbonylphenyl, 4-(4'-ethylphenyl)oxycarbonylphenyl, 
4-(4'-chlorophenyl)oxycarbonylphenyl, 
4-(4'-ethoxyphenyl)oxycarbonylphenyl, 2-(6-phenyloxycarbonylnaphthyl), 
4-acetyloxyphenyl, 3-acetyloxyphenyl, 4-ethylcarbonyloxyphenyl, 
2-ethylcarbonyloxyphenyl, 4-n-propylcarbonyloxyphenyl, 
4-n-pentylcarbonyloxyphenyl, 4-n-octylcarbonyloxyphenyl, 
4-cyclohexylcarbonyloxyphenyl, 1-(4-acetyloxynaphthyl), 
1-(5-acetyloxynaphthyl), 2-(6-ethylcarbonyloxynaphthyl), 
4-allylcarbonyloxyphenyl, 4-benzylcarbonyloxyphenyl, 
4-phenethylcarbonyloxyphenyl, 2-(6-benzylcarbonyloxynaphthyl), 
4-phenylcarbonyloxyphenyl, 4-(4'-methylphenyl)carbonyloxyphenyl, 
4-(2'-methylphenyl)carbonyloxyphenyl, 
4-(4'-chlorophenyl)carbonyloxyphenyl, 4-(2'-chlorophenyl)carbonyloxyphenyl 
, 1-(4-phenylcarbonyloxynaphthyl), 2-(6-phenylcarbonyloxynaphthyl), 
4-methylthiophenyl, 2-methylthiophenyl, 4-ethylthiophenyl, 
3-ethylthiophenyl, 4-n-propylthiophenyl, 4-n-butylthiophenyl, 
4-n-hexylthiophenyl, 4-n-octylthiophenyl, 4-cyclohexylthiophenyl, 
4-benzylthiophenyl, 3-benzylthiophenyl, 4-(4'-chlorobenzylthio)phenyl, 
4-phenylthiophenyl, 3-phenylthiophenyl, 4-(4'-methylphenylthio)phenyl, 
4-(4'-methoxyphenylthio)phenyl, 4-(4'-chlorophenylthio)phenyl, 
1-(4-methylthionaphthyl), 2-(6-ethylthionaphthyl), 
2-(6-phenylthionaphthyl), 4-fluorophenyl, 3-fluorophenyl, 2-fluorophenyl, 
4-chlorophenyl, 3-chlorophenyl, 2-chlorophenyl, 4-bromophenyl, 
1-(4-chloronaphthyl), 2-(4-chloronaphthyl), 2-(6-bromonaphthyl), 
4-nitrophenyl, 3-nitrophenyl, 4-formylphenyl, 3-formylphenyl, 
2-formylphenyl, 1-(4-formylnaphthyl), 2-(1-formylnaphthyl), 
4-hydroxyphenyl, 3-hydroxyphenyl, 2-hydroxyphenyl, 1-(4-hydroxynaphthyl), 
2-(6-hydroxynaphthyl), 4-cyanophenyl, 2-cyanophenyl, 2-(6-cyanonaphthyl), 
2-chloro-4-nitrophenyl, 4-chloro-2-nitrophenyl, 6-chloro-3-methylphenyl, 
2-chloro-6-methylphenyl, 4-chloro-2-methylphenyl, 4-chloro-3-methylphenyl, 
2,4-dimethylphenyl, 2,5,-dimethylphenyl, 3,4-dimethylphenyl, 
3,5-dimethylphenyl, 2,6-dimethylphenyl, 2,3,5-trimethylphenyl, 
2,3,6-trimethylphenyl, 2,4,6-trimethylphenyl, 2,3-dichlorophenyl, 
2,4-dichlorophenyl, 2,5-dichlorophenyl, 2,6-dichlorophenyl, 
3,4-dichlorophenyl, 3,5-dichlorophenyl, 2,4,6-trichlorophenyl, 
2-methoxy-4-methylphenyl, 2,6-dimethoxyphenyl, 3,5-dimethoxyphenyl, 
3,5-diethoxyphenyl, 3,5-di-n-butoxyphenyl, 3,4,5-trimethoxyphenyl and 
1-(2,4-dichloronaphthyl). 
The compound represented by the formula (1) in the invention has a 
carbamate group on a salicylic acid skeleton. The carbamate group locates 
on the position 3, 4, 5 or 6, preferably on the position 3, 4 or 5, most 
preferably on the position 4 or 5 in the salicylic acid skeleton. That is, 
most preferred salicylic acid derivative is represented by the formula 
(1-a): 
##STR5## 
wherein X.sub.1, X.sub.2, Y.sub.1, Y.sub.2, R.sub.1 and R.sub.2 are the 
same as above, or by the formula (1-b): 
##STR6## 
wherein X.sub.1, X.sub.2, Y.sub.1, Y.sub.2, R.sub.1 and R.sub.2 are the 
same as above. 
Exemplary salicylic acid derivative represented by the formula (1) and the 
metal salt of the derivative which can be used for the invention will be 
enumerated below. However, it is to be understood that the invention is 
not limited by the following compounds. 
______________________________________ 
No. Compound 
______________________________________ 
1) 3-(isopropyloxycarbonylamino)salicylic acid 
2) 3-(isopentyloxycarbonylamino)salicylic acid 
3) 3-(n-hexyloxycarbonylamino)salicylic acid 
4) 3-(n-octyloxycarbonylamino)salicylic acid 
5) 3-(n-decyloxycarbonylamino)salicylic acid 
6) 3-[(4'-methylcyclohexyl)oxycarbonylamino]salicylic acid 
7) 3-[(2'-cyclohexylethyl)oxycarbonylamino]salicylic acid 
8) 3-(allyloxycarbonylamino)salicylic acid 
9) 3-[(2'-hexenyl)oxycarbonylamino]salicylic acid 
10) 3-[(2'-ethoxyethyl)oxycarbonylamino]salicylic acid 
11) 3-[(3'-n-hexyloxypropyl)oxycarbonylamino]salicylic acid 
12) 3-[(2'-benzyloxyethyl)oxycarbonylamino]salicylic acid 
13) 3-(phenoxymethyloxycarbonylamino)salicylic acid 
14) 3-[(2'-phenoxyethyl)oxycarbonylamino]salicylic acid 
15) 3-[(2'-(4-chlorophenyl)oxyethyloxycarbonylamino]salicylic 
acid 
16) 3-[2'-(4-methoxyphenyl)oxyethyloxycarbonylamino)salicylic 
acid 
17) 3-[(2'-phenoxyethoxyethyl)oxycarbonylamino]salicylic acid 
18) 3-(cinnamyloxycarbonylamino)salicylic acid 
19) 3-[(2'-n-butylthioethyl)oxycarbonylamino]salicylic acid 
20) 3-[(2'-methoxyethylthioethyl)oxycarbonylamino]salicylic 
acid 
21) 3-[(2'-allylthioethyl)oxycarbonylamino]salicylic acid 
22) 3-[(2'-benzylthioethyl)oxycarbonylamino]salicylic acid 
23) 3-[(2'-phenylthioethyl)oxycarbonylamino]salicylic acid 
24) 3-[(7'-chloroheptyl)oxycarbonylamino]salicylic acid 
25) 3-(benzyloxycarbonylamino)salicylic acid 
26) 3-[(4'-methylbenzyl)oxycarbonylamino]salicylic acid 
27) 3-[(4'-chlorobenzyl)oxycarbonylamino]salicylic acid 
28) 3-[(3'-phenoxybenzyl)oxycarbonylamino]salicylic acid 
29) 3-(phenyloxycarbonylamino)salicylic acid 
30) 3-[ 8 (2'-naphthyl oxycarbonylamino]salicylic acid 
31) 3-[(3'-furyl)oxycarbonylamino]salicylic acid 
32) 3-[(3'-phenylphenyl)oxycarbonylamino]salicylic acid 
33) 3-[(4'-methylphenyl)oxycarbonylamino]salicylic acid 
34) 3-[(4'-n-butylphenyl)oxycarbonylamino]salicylic acid 
35) 3-[(4'-tert-butylphenyl)oxycarbonylamino]salicylic acid 
36) 3-[(4'-cyclohexylphenyl)oxycarbonylamino]salicylic acid 
37) 3-[(3'-methoxyphenyl)oxycarbonylamino]salicylic acid 
38) 3-[(4'-n-butoxyphenyl)oxycarbonylamino]salicylic acid 
39) 3-[(4'-n-octyloxyphenyl)oxycarbonylamino]salicylic acid 
40) 3-[(4'-phenoxyphenyl)oxycarbonylamino]salicylic acid 
41) 3-[(2'-acetylphenyl)oxycarbonylamino]salicylic acid 
42) 3-[(4'-allylcarbonylphenyl)oxycarbonylamino]salicylic acid 
43) 3-[(4'-phenylcarbonylphenyl)oxycarbonylamino]salicylic 
acid 
44) 3-[(4'-n-butoxycarbonylphenyl)oxycarbonylamino]salicylic 
acid 
45) 3-[(4'-benzyloxyphenyl)oxycarbonylamino]salicylic acid 
46) 3-[(4'-acetyloxyphenyl)oxycarbonylamino]salicylic acid 
47) 3-[(4'-ethylthiophenyl)oxycarbonylamino]salicylic acid 
48) 3-[(4'-fluorophenyl)oxycarbonylamino]salicylic acid 
49) 3-[(4'-chlorophenyl)oxycarbonylamino]salicylic acid 
50) 3-[(4'-nitrophenyl)oxycarbonylamino]salicylic acid 
51) 3-[(4'-formylphenyl)oxycarbonylamino]salicylic acid 
52) 3-[(4'-hydroxyphenyl)oxycarbonylamino]salicylic acid 
53) 3-[(4'-cyanophenyl)oxycarbonylamino]salicylic acid 
54) 3-[(2',4'-dimethylphenyl)oxycarbonylamino]salicylic acid 
55) 3-[(3',5'-dichlorophenyl)oxycarbonylamino]salicylic acid 
56) 5-methyl-3-(n-hexyloxycarbonylamino)salicylic acid 
57) 5-cyclohexyl-3-(phenyloxycarbonylamino)salicylic acid 
58) 
5-cumyl-3-(n-hexyloxycarbonylamino)salicylic acid 
59) 3-(n-octylthiolcarbonylamino)salicylic acid 
60) 3-[(4'-chlorobenzyl)thiolcarbonylamino]salicylic acid 
61) 3-[(3'-methylphenyl)thiolcarbonylamino]salicylic acid 
62) 3-(n-butylthiolthiocarbonylamino)salicylic acid 
63) 3-(phenylthiolthiocarbonylamino)salicylic acid 
64) 3-[(4'-ethoxyphenyl)thiolthiocarbonylamino]salicylic acid 
65) 3-(N-phenyl-N-phenyloxycarbonylamino)salicylic acid 
66) 4-(methyloxycarbonylamino)salicylic acid 
67) 4-(ethyloxycarbonylamino)salicylic acid 
68) 4-(n-propyloxycarbonylamino)salicylic acid 
69) 4-(isopropyloxycarbonylamino)salicylic acid 
70) 4-(n-butyloxycarbonylamino)salicylic acid 
71) 4-(isobutyloxycarbonylamino)salicylic acid 
72) 4-(sec-butyloxycarbonylamino)salicylic acid 
73) 4-(n-pentyloxycarbonylamino)salicylic acid 
74) 4-(isopentyloxycarbonylamino)salicylic acid 
75) 4-(n-hexyloxycarbonylamino)salicylic acid 
76) 4-(n-heptyloxycarbonylamino)salicylic acid 
77) 4-(n-octyloxycarbonylamino)salicylic acid 
78) 4-[(2'-ethylhexyl)oxycarbonylamino]salicylic acid 
79) 4-(n-nonyloxycarbonylamino)salicylic acid 
80) 4-(n-decyloxycarbonylamino)salicylic acid 
81) 4-(n-undecyloxycarbonylamino)salicylic acid 
82) 4-(n-dodecyloxycarbonylamino)salicylic acid 
83) 4-(n-tridecyloxycarbonylamino)salicylic acid 
84) 4-(n-tetradecyloxycarbonylamino)salicylic acid 
85) 4-(n-pentadecyloxycarbonylamino)salicylic acid 
86) 4-(n-hexadecyloxycarbonylamino)salicylic acid 
87) 4-(n-heptadecyloxycarbonylamino)salicylic acid 
88) 4-(n-octadecyloxycarbonylamino)salicylic acid 
89) 4-(cyclopentyloxycarbonylamino)salicylic acid 
90) 4-(cyclohexyloxycarbonylamino)salicy-ic acid 
91) 4-[(4'-tert-butylcyclohexyl)oxycarbonylamino]salicylic acid 
92) 4-(cycloheptyloxycarbonylamino)salicylic acid 
93) 4-(cyclooctyloxycarbonylamino)salicylic acid 
94) 4-(cyclohexylmethyloxycarbonylamino)salicylic acid 
95) 4-[(2'-tetrahydrofurfuryl)oxycarbonylamino]salicylic acid 
96) 4-[(2'-methoxyethyl)oxycarbonylamino]salicylic acid 
97) 4-[(2'-n-hexyloxyethyl)oxycarbonylamino]salicylic acid 
98) 4-[(2'-n-octyloxyethyl)oxycarbonylamino]salicylic acid 
99) 4-[(3'-ethoxypropyl)oxycarbonylamino]salicylic acid 
100) 4-[(3'-n-butoxypropyl)oxycarbonylamino]salicylic acid 
101) 4-[(3'-n-octyloxypropyl)oxycarbonylamino]salicylic acid 
102) 4-[(2'-n-butoxyethoxyethyl)oxycarbonylamino]salicylic acid 
103) 4-[(2'-benzyloxyethyl)oxycarbonylamino]salicylic acid 
104) 4-[(phenoxymethyl)oxycarbonylamino]salicylic acid 
105) 4-[(2'-phenoxyethyl)oxycarbonylamino]salicylic acid 
106) 4-[2'-(4-chlorophenyl)oxyethyloxycarbonylamino]salicylic 
acid 
107) 4-[2'-(4-methoxyphenyl)oxyethyloxycarbonylamino]salicylic 
acid 
108) 4-[(2'-phenoxyethoxyethyl)oxycarbonylamino]salicylic acid 
109) 4-[(3'-n-butylthiopropyl)oxycarbonylamino]salicylic acid 
110) 4-[(6'-ethylthiohexyl)oxycarbonylamino]salicylic acid 
111) 4-[(2'-benzylthioethyl)oxycarbonylamino]salicylic acid 
112) 4-[(2'-phenylthioethyl)oxycarbonylamino]salicylic acid 
113) 4-[(2'-chloroethyl)oxycarbonylamino]salicylic acid 
114) 4-[(9'-decenyl)oxycarbonylamino]salicylic acid 
115) 4-(benzyloxycarbonylamino)salicylic acid 
116) 4-[(4'-methylbenzyl)oxycarbonylamino]salicylic acid 
117) 4-[(4'-chlorobenzyl)oxycarbonylamino]salicylic acid 
118) 4-[(2'-phenylethyl)oxycarbonylamino]salicylic acid 
119) 4-(phenyloxycarbonylamino)salicylic acid 
120) 4-[(1'-naphthyl)oxycarbonylamino]salicylic acid 
121) 4-[(2'-naphthyl)oxycarbonylamino]salicylic acid 
122) 4-[(2'-furyl)oxycarbonylamino] 9 salicylic acid 
123) 4-[(4'-phenylphenyl)oxycarbonylamino]salicylic acid 
124) 4-[(4'-methylphenyl)oxycarbonylamino]salicylic acid 
125) 4-[(3'-methylphenyl)oxycarbonylamino]salicylic acid 
126) 4-[(2'-methylphenyl)oxycarbonylamino]salicylic acid 
127) 4-[(4'-ethylphenyl)oxycarbonylamino]salicylic acid 
128) 4-[(4'-tert-butylphenyl)oxycarbonylamino]salicylic acid 
129) 4-[(4'-cyclohexylphenyl)oxycarbonylamino]salicylic acid 
130) 4-[(2'-cyclohexylphenyl)oxycarbonylamino]salicylic acid 
131) 4-[(4'-cumylphenyl)oxycarbonylamino]salicylic acid 
132) 4-[(4'-methoxyphenyl)oxycarbonylamino]salicylic acid 
133) 4-[(3'-methoxyphenyl)oxycarbonylamino]salicylic acid 
134) 4-[(2'-ethoxyphenyl)oxycarbonylamino]salicylic acid 
135) 4-[(4'-n-butoxyphenyl)oxycarbonylamino]salicylic acid 
136) 4-[(4'-n-hexyloxyphenyl)oxycarbonylamino]salicylic acid 
137) 4-[(4'-benzyloxyphenyl)oxycarbonylamino]salicylic acid 
138) 4-[4'-(4-benzyloxycumyl)phenyloxycarbonylamino]salicylic 
acid 
139) 4-[(4'-phenoxyphenyl)oxycarbonylamino]salicylic acid 
140) 4-[2'-(6-benzyloxy)naphthyloxycarbonylamino]salicylic acid 
141) 4-[(4'-phenylcarbonylphenyl)oxycarbonylamino]salicylic 
acid 
142) 4-[(4'-acetylphenyl)oxycarbonylamino]salicylic acid 
143) 4-[(4'-ethoxycarbonylphenyl)oxycarbonylamino]salicylic 
acid 
144) 4-[(4'-cyclohexyloxycarbonylphenyl)oxycarbonylamino]- 
salicylic acid 
145) 4-[(4'-n-propylcarbonyloxyphenyl)oxycarbonylamino]- 
salicylic acid 
146) 4-[(4'-n-methylthiophenyl)oxycarbonylamino]salicylic acid 
147) 4-[(4'-benzylthiophenyl)oxycarbonylamino]salicylic acid 
148) 4-[(4'-fluorophenyl)oxycarbonylamino]salicylic acid 
149) 4-[(2'-fluorophenyl)oxycarbonylamino]salicylic acid 
150) 4-[(4'-chlorophenyl oxycarbonylamino]salicylic acid 
151) 4-(3'-chlorophenyl)oxycarbonylamino]salicylic acid 
152) 4-[(4'-bromophenyl)oxycarbonylamino]salicylic acid 
153) 4-[(4'-nitrophenyl)oxycarbonylamino]salicylic acid 
154) 4-[(4'-formylphenyl)oxycarbonylamino]salicylic acid 
155) 4-[(4'-cyanophenyl)oxycarbonylamino]salicylic acid 
156) 4-[(2',4'-dimethylphenyl)oxycarbonylamino]salicylic acid 
157) 4-[(3',5'-dimethylphenyl)oxycarbonylamino]salicylic acid 
158) 4-[(2',4'-dichlorophenyl)oxycarbonylamino]salicylic acid 
159) 4-[(3',5'-dimethoxyphenyl)oxycarbonylamino]salicylic acid 
160) 4-[(3'-nitro-4'-chlorophenyl)oxycarbonylamino]salicylic acid 
161) 4-[(4'-chloro-2'-methylphenyl)oxycarbonylamino]salicylic 
acid 
162) 4-(n-octylthiolcarbonylamino)salicylic acid 
163) 4-(phenylthiolcarbonylamino)salicylic acid 
164) 4-[(4'-ethoxyphenylthiol)carbonylamino]salicylic acid 
165) 4-(n-hexylthiolthiocarbonylamino)salicylic acid 
166) 4-[(4'-methylphenylthiol)thiocarbonylamino]salicylic acid 
167) 4-(n-decyloxythiocarbonylamino)salicylic acid 
168) 4-(N-n-butyl-N-heptyloxycarbonylamino)salicylic acid 
169) 3-ethyl-4-(phenyloxycarbonylamino)salicylic acid 
170) 3-chloro-4-(n-butyloxycarbonylamino)salicylic acid 
171) 5-(methyloxycarbonylamino)salicylic acid 
172) 5-(ethyloxycarbonylamino)salicylic acid 
173) 5-(n-propyloxycarbonylamino)salicylic acid 
174) 5-(n-butyloxycarbonylamino)salicylic acid 
175) 5-(isobutyloxycarbonylamino)salicylic acid 
176) 5-(n-pentyloxycarbonylamino)salicylic acid 
177) 5-(isopentyloxycarbonylamino)salicylic acid 
178) 5-(n-hexyloxycarbonylamino)salicylic acid 
179) 5-(n-heptyloxycarbonylamino)salicylic acid 
180) 5-(n-octyloxycarbonylamino)salicylic acid 
181) 5-[(2'-ethylhexyl)oxycarbonylamino]salicylic acid 
182) 5-(n-nonyloxycarbonylamino)salicylic acid 
183) 5-(n-decyloxycarbonylamino)salicylic acid 
184) 5-(n-undecyloxycarbonylamino)salicylic acid 
185) 5-(n-dodecyloxycarbonylamino)salicylic acid 
186) 5-(n-tetradecyloxycarbonylamino)salicylic acid 
187) 5-(n-hexadecyloxycarbonylamino)salicylic acid 
188) 5-(cyclohexyloxycarbonylamino)salicylic acid 
189) 5-[(4'-methylcyclohexyl)oxycarbonylamino]salicylic acid 
190) 5-[(4'-tert-butylcyclohexyl)oxycarbonylamino]salicylic acid 
191) 5-[(2'-cyclohexylethyl)oxycarbonylamino]salicylic acid 
192) 5-(cyclooctyloxycarbonylamino)salicylic acid 
193) 5-[(2'-tetrahydrofurfuryl)oxycarbonylamino]salicylic acid 
194) 5-[(2'-methoxyethyl)oxycarbonylamino]salicylic acid 
195) 5-[(2'-n-hexyloxyethyl)oxycarbonylamino]salicylic acid 
196) 5-[(3'-ethoxypropyl)oxycarbonylamino]salicylic acid 
197) 5-[(3'-isopropoxypropyl)oxycarbonylamino]salicylic acid 
198) 5-[(2'-methoxyethoxyethyl)oxycarbonylamino]salicylic acid 
199) 5-(phenoxymethyloxycarbonylamino)salicylic acid 
200) 5-(2'-phenoxyethyloxycarbonylamino)salicylic acid 
201) 5-[2'-(4-chlorophenyl)oxyethyloxycarbonylamino]salicylic 
acid 
202) 5-[2'-(4-methoxyphenyl)oxyethyloxycarbonylamino]salicylic 
acid 
203) 5-[(2'-phenoxyethoxyethyl)oxycarbonylamino]salicylic acid 
204) 5-[(2'-n-hexylthioethyl)oxycarbonylamino]salicylic acid 
205) 5-[(2'-phenylthioethyl)oxycarbonylamino]salicylic acid 
206) 5-(2'-chloroethyloxycarbonylamino)salicylic acid 
207) 5-(5'-hexenyloxycarbonylamino)salicylic acid 
208) 5-(benzyloxycarbonylamino)salicylic acid 
209) 5-[(4'-methylbenzyl)oxycarbonylamino]salicylic acid 
210) 5-[(4'-chlorobenzyl)oxycarbonylamino]salicylic acid 
211) 5-[(2'-phenylethyl)oxycarbonylamino]salicylic acid 
212) 5-(phenyloxycarbonylamino)salicylic acid 
213) 5-[(2'-naphthyl)oxycarbonylamino]salicylic acid 
214) 5-[(4'-phenylphenyl)oxycarbonylamino]salicylic acid 
215) 5-[(3' 40 -methylphenyl)oxycarbonylamino]salicylic acid 
216) 5-[(4'-ethylphenyl)oxycarbonylamino]salicylic acid 
217) 5-[(4'-cyclohexylphenyl)oxycarbonylamino]salicylic acid 
218) 5-[(4'-cumylphenyl)oxycarbonylamino]salicylic acid 
219) 5-[(4'-methoxyphenyl)oxycarbonylamino]salicylic acid 
220) 5-[(3'-ethoxyphenyl)oxycarbonylamino]salicylic acid 
221) 5-[(4'-n-butoxyphenyl)oxycarbonylamino]salicylic acid 
222) 5-[(4'-phenoxyphenyl)oxycarbonylamino]salicylic acid 
223) 5-[(4'-acetylphenyl)oxycarbonylamino]salicylic acid 
224) 5-[(4'-methoxycarbonylphenyl)oxycarbonylamino]salicylic 
acid 
225) 5-[(4'-ethylcarbonyloxyphenyl)oxycarbonylamino]salicylic 
acid 
226) 5-[(4'-ethylthiophenyl)oxycarbonylamino]salicylic acid 
227) 5-[(4'-phenylthiophenyl)oxycarbonylamino]salicylic acid 
228) 5-[(4'-fluorophenyl)oxycarbonylamino]salicylic acid 
229) 5-[(3'-fluorophenyl)oxycarbonylaminosalicylic acid 
230) 5-[(4'-chlorophenyl)oxycarbonylamino]salicylic acid 
231) 5-[(3'-chlorophenyl)oxycarbonylamino]salicylic acid 
232) 5-[(2'-chlorophenyl)oxycarbonylamino]salicylic acid 
233) 5-[(2'-formylphenyl)oxycarbonylamino]salicylic acid 
234) 5-[(2'-cyanophenyl)oxycarbonylamino]salicylic acid 
235) 5-[(2',4'-dimethylphenyl)oxycarbonylamino]salicylic acid 
236) 5-[(3',5'-dimethylphenyl)oxycarbonylamino]salicylic acid 
237) 5-[(3'-nitro-4'-chlorophenyl)oxycarbonylamino]salicylic 
acid 
238) 5-(n-butylthiolcarbonylamino)salicylic acid 
239) 5-(phenylthiolcarbonylamino)salicylic acid 
240) 5-[(2'-naphthylthiol)carbonylamino]salicylic acid 
241) 5-[(4'-methylphenylthiol)carbonylamino]salicylic acid 
242) 5-(n-heptylthiolthiocarbonylamino)salicylic acid 
243) 5-(n-dodecylthiolthiocarbonylamino)salicylic acid 
244) 5-(n-pentyloxythiocarbonylamino)salicylic acid 
245) 5-[(4'-chlorophenyl)oxythiocarbonylamino]salicylic acid 
246) 5-(N-methyl-N-phenyloxycarbonylamino)salicylic acid 
247) 3-methyl-5-(methyloxycarbonylamino)salicylic acid 
248) 3-ethoxy 5-(n-butyloxycarbonylamino)salicylic acid 
249) 3-.alpha.-methylbenzyl-5-(ethyloxycarbonylamino)salicylic acid 
250) 3-phenyl-5-(n-hexyloxycarbonylamino)salicylic acid 
251) 6-(n-propyloxycarbonylamino)salicylic acid 
252) 6-(isopentyloxycarbonylamino)salicylic acid 
253) 6-(n-heptyloxycarbonylamino)salicylic acid 
254) 6-[(1'-methylheptyl)oxycarbonylamino]salicylic acid 
255) 6-(n-dodecyloxycarbonylamino)salicylic acid 
256) 6-[(2',5'-dimethylcyclohexyl)oxycarbonylamino]salicylic 
acid 
257) 6-[(2'-cyclohexylmethyl)oxycarbonylamino]salicylic acid 
258) 6-[(3'-butenyl)oxycarbonylamino]salicylic acid 
259) 6-[(10'-undecenyl)oxycarbonylamino]salicylic acid 
260) 6-[(2'-isopropoxyethyl)oxycarbonylamino]salicylic acid 
261) 6-[(3'-cyclohexyloxypropyl)oxycarbonylamino]salicylic acid 
262) 6-[(2'-phenethyloxyethyl)oxycarbonylamino]salicylic acid 
263) 6-[(2'-phenoxyethyl)oxycarbonylamino]salicylic acid 
264) 6-[(2'-(4-chlorophenoxy)ethyloxycarbonylamino]salicylic 
acid 
265) 6-[(3'-n-buthylthiopropyl)oxycarbonylamino]salicylic acid 
266) 6-[(3'-(4-methylbenzylthio)propyloxycarbonylamino]- 
salicylic acid 
267) 6-[(2'-phenylthioethyl)oxycarbonylamino]salicylic acid 
268) 6-[(2'-tetrahydrofurfuryl)oxycarbonylamino]salicylic acid 
269) 6-[(2'-chloroethyl)oxycarbonylamino]salicylic acid 
270) 6-(benzyloxycarbonylamino)salicylic acid 
271) 6-[(4'-chlorobenzyl)oxycarbonylamino]salicylic acid 
272) 6-(phenyloxycarbonylamino)salicylic acid 
273) 6-[(1'-naphthyl)oxycarbonylamino]salicylic acid 
274) 6-[(4'-phenylphenyl)oxycarbonylamino]salicylic acid 
275) 6-[(2'-ethylphenyl)oxycarbonylamino] 9 salicylic acid 
276) 6-[(4'-tert-butylphenyl)oxycarbonylamino]salicylic acid 
277) 6-[(3'-methoxyphenyl)oxycarbonylamino]salicylic acid 
278) 6-[(4'-n-hexyloxyphenyl)oxycarbonylamino]salicylic acid 
279) 6-[(3'-phenoxyphenyl)oxycarbonylamino]salicylic acid 
280) 6-[(4'-ethylcarbonylphenyl)oxycarbonylamino]salicylic acid 
281) 6-[(4'-benzylcarbonylphenyl)oxycarbonylamino]salicylic 
acid 
282) 6-[(4'-methoxycarbonylphenyl)oxycarbonylamino]salicylic 
acid 
283) 6-[(4'-methylthiophenyl)oxycarbonylamino]salicylic acid 
284) 6-[(3'-fluorophenyl)oxycarbonylamino]salicylic acid 
285) 6-[(2'-chlorophenyl)oxycarbonylamino]salicylic acid 
286) 6-[(3'-nitrophenyl)oxycarbonylamino]salicylic acid 
287) 6-[(2'-formylphenyl)oxycarbonylamino]salicylic acid 
288) 6-[(3'-hydroxyphenyl)oxycarbonylamino]salicylic acid 
289) 6-[(4'-cyanophenyl)oxycarbonylamino]salicylic acid 
290) 6-[(3',4'-dimethylphenyl)oxycarbonylamino]salicylic acid 
291) 6-[(2',4'-dichlorophenyl)oxycarbonylamino]salicylic acid 
292) 3-ethyl-6-(n-hexyloxycarbonylamino)salicylic acid 
293) 3-tert-butyl-6-(phenyloxycarbonylamino)salicylic acid 
294) 6-(N-ethyl-N-phenyloxycarbonylamino)salicylic acid 
295) 6-(n-octylthiolcarbonylamino)salicylic acid 
296) 6-[(4'-methylbenzyl)thiolcarbonylamino]salicylic acid 
297) 6-[(4'-methylphenyl)thiolcarbonylamino]salicylic acid 
298) 6-(n-octylthiolthiocarbonylamino)salicylic acid 
299) 6-(phenylthiolthiocarbonylamino)salicylic acid 
300) 6-[(4'-methoxyphenyl)thiolthiocarbonylamino]salicylic 
______________________________________ 
acid 
The metal salt of salicylic acid derivative represented by the formula (1) 
which is used for the electron accepting compound in the heat-sensitive 
recording material of the invention includes salts of monovalent metals 
such as sodium, potassium and lithium and polyvalent metals having 2, 3 
and 4 valence. In the case of using the metal salt singly as an electron 
accepting compound, the salt is preferably a metal salt which is 
difficultly soluble or insoluble in water and composed of a polyvalent 
metal of 2, 3 and 4 valence, more preferably a salt of the polyvalent 
metal having 2 or 3 valence. 
Exemplary salts of the polyvalent metal are salts of zinc, cadmium, 
mercury, magnesium, calcium, barium, nickel, tin, lead, gallium, chromium, 
copper, molybdenum, wolfram, zirconium, strontium, manganese, cobalt, 
titanium, aluminum and iron, preferably salts of zinc, magnesium, calcium, 
barium, nickel, manganese, cobalt and aluminum, more preferably salts of 
zinc, magnesium, nickel and manganese, most preferably a zinc salt. 
Any of the salicylic acid derivatives enumerated above can form salts of 
the metal having from 1 to 4 valence. The metal salt of the salicylic acid 
derivative can be used for the heat-sensitive recording material of the 
invention. The salicylic acid derivative represented by the formula (1) 
and the metal salt of the derivative can be used singly or as a mixture 
for the electron accepting compound in the heat-sensitive recording 
material of the invention. For example, a combination of one or more 
salicylic acid derivative and a metal salt of salicylic acid derivative 
can also be used. 
The salicylic acid derivative represented by the formula (1) in the 
invention can be prepared by various processes. 
The preparation process of the invention is particularly preferred. 
In the process of the invention, the aminosalicylic acid derivative 
represented by the formula (2): 
##STR7## 
wherein X.sub.1, X.sub.2 and R.sub.1 is the same as above, is reacted with 
a compound represented by the formula (3): 
##STR8## 
wherein Y.sub.1, Y.sub.2 and R.sub.2 are the same as above and Z is a 
halogen atom, in the presence of an alcohol-based solvent to obtain the 
salicylic acid derivative represented by the formula (1). 
The preparation process of the salicylic acid derivative of the invention 
is characterized by conducting the reaction in the presence of an 
alcohol-based solvent. It has not yet been known to prepare the compound 
of the formula (1) in the presence of such a solvent. 
It has been already mentioned that some of the compounds represented by the 
formula (1) were prepared by reacting the compound of the formula (2) with 
the compound of the formula (3). As a solvent in carrying out the 
reaction, dry pyridine was used in German Patent 2749518 and water was 
used in Bull. de. Socie. Chim. France, 1189 (1955) and J. Pharm. Sci., 52, 
927 (1963). 
These known reaction solvents led to the low yield or formation of 
by-products and thus the salicylic acid derivative represented by the 
formula (1) could not be obtained in high yield and high purity. 
As a result of an intensive investigation particularly on the reaction 
solvent, the present inventors found that a large amount of by-products 
other than the compound of the formula (1) was formed by reacting the 
compound of the formula (2) with the compound of the formula (3) in the 
presence of an ester-based solvent such as ethyl acetate and butyl 
acetate, the compound of the formula (1) could not be obtained in high 
yield, and extremely complex procedures were required for removing the 
by-products. The inventors have surprisingly found that the salicylic acid 
derivative of the formula (1) can be prepared in high yield and high 
purity by carrying out the reaction in the presence of the alcohol-based 
solvent. 
The compound represented by the formula (2) can be prepared by known 
processes described, for example, in J. Prakt, Chem., 61, 532 (1900), J. 
Org. Chem., 19, 510 (1954), Japanese Laid-Open Patent Sho 57-26652, German 
Patent 3638364, and J. Chem. Soc., 2049 (1953). 
For example, a 3-aminosalicylic acid derivative can be prepared by reducing 
3-nitrosalicylic acid. 
A 4-aminosalicylic acid derivative can be prepared by reacting a 
3-aminophenol derivative with carbon dioxide in the presence of a base 
such as potassium carbonate, or by reducing 4-nitrosalicylic acid. 
A 5-aminosalicylic acid derivative can be prepared by reacting a salicylic 
acid derivative with a diazonium salt and successively reducing the 
resulting diazonium compound. 
A 6-aminosalicylic acid derivative can be prepared by reducing a 
6-nitrosalicylic acid derivative. 
Z in the formula (3) is a halogen atom, preferably a fluorine, chlorine or 
bromine atom, more preferably a chlorine atom. 
The compound represented by the formula (3) can be prepared by known 
processes described, for example, in Methoden Der Organishen Chemie, 8, 
1018 (1952); J. Am. Chem. Soc., 72, 1254 (1950); Angewandte Chemie, 
International Edition, 4, 281 (1967); and Chem. Review, 73, 75 (1973). 
For example, the compound wherein Z in the formula (3) is chlorine can be 
prepared by reacting phosgene or thiophosgene with alcohols, phenols, 
thiols or thiophenols. 
The alcohol-based solvents which can be used for the process of the 
invention is preferably alcohols having from 1 to 8 carbon atoms and 
includes, for example, methanol, ethanol, propanol, butanol, pentanol, 
heptanol, octanol, cyclohexanol, methyl cellosolve and ethyl cellosolve. 
These solvents can be used singly or as a mixture. 
The process of the invention is characterized by reacting the compound of 
the formula (2) with the compound of the formula (3) in the presence of 
the alcohol-based solvent. The alcohol-based solvent can be used in 
combination with other organic solvents. In such cases, when the amount of 
the alcohol-based solvent is less than 10% by weight for the total amount 
of the solvents, reaction requires a long time or an unreacted compound of 
the formula (2) remains after the reaction. Accordingly, the amount of the 
alcohol-based solvent is preferably 10% by weight or more, more preferably 
30% by weight or more, most preferably 50% by weight or more in the total 
amount of the solvents. 
Other organic solvents which can be used in combination with the 
alcohol-based solvent include, for example, benzene, toluene, xylene, 
pentane, hexane, heptane, octane, cyclohexane and other hydrocarbon 
solvents; ethyl acetate, butyl acetate, amyl acetate and other ester 
solvents; diethyl ether, dioxane, tetrahydrofuran and other ether 
solvents; and dichloromethane, chloroform, dichloroethane, chlorobenzene, 
dichlorobenzene and other halogenated hydrocarbon solvents. 
When the alcohol-based solvent has good compatibility with water as 
particularly in the case of methanol, ethanol and propanol, a mixture of 
the solvent with water can also be used. In view of the solubility of the 
compound represented by the formula (2), the amount of water is preferably 
50% by weight or less, more preferably 30% by weight or less in the total 
weight of the solvent mixture. 
No particular limitation is imposed upon the amount of the solvent. 
However, too much amount of the solvent is unfavorable in view of 
production efficiency and too small amount of the solvent requires a long 
reaction time, which is also unfavorable in view of production efficiency. 
The amount is preferably from 0.5 to 200 times by weight, more preferably 
from 1 to 100 times by weight for the amount of the compound represented 
by the formula (2). 
The amount of the compound represented by the formula (3) is usually from 
0.9 to 1.5 moles, preferably from 1 to 1.2 moles per mole of the compound 
represented by the formula (2). 
The reaction temperature is usually from -20.degree. C. to the boiling 
point of the solvent, preferably from 0.degree. C. to the boiling point of 
the solvent. 
The reaction time depends upon the reaction temperature and usually 
requires from several minutes to several hours. The progress of the 
reaction can be monitored with a known analytical means such as high 
performance liquid chromatography by persons skilled in the art. 
By using such means, the reaction can also be terminated at a desired 
reaction rate, the reaction product is post treated and the salicylic acid 
derivative represented by the formula (1) can be isolated. 
Even though the reaction is carried out in the absence of the base as a 
dehalogenating agent, the desired salicylic acid derivative can be 
obtained by the action of the compound of the formula (2) as a 
dehalogenating agent. However, the reaction is preferably carried out in 
the presence of the base. Exemplary bases which can be preferably used 
include sodium carbonate, potassium carbonate, sodium hydrogen carbonate, 
potassium hydrogen carbonate, sodium hydroxide, potassium hydroxide and 
other inorganic bases. These bases can be used singly or as a mixture. 
After finishing the reaction, the reaction product can be isolated by usual 
post-treatment. 
The salicylic acid derivative of the formula (1) which is prepared by the 
process of the invention has high purity of usually 98% or more. 
Purification to further high purity is preferred in order to use the 
salicylic acid derivative of the formula (1) or the metal salt of the 
derivative for the electron accepting compound of the heat-sensitive 
recording material. Further purification can be carried out, if desired, 
by known purification methods such as recrystallization and column 
chromatography. 
The metal salt of the salicylic acid derivative represented by the formula 
(1) as an electron accepting compound in the heat-sensitive recording 
material of the invention comprises a salt of monovalent metals such as 
sodium, potassium and lithium and polyvalent metals of 2 to 4 valence. The 
metal salt can be prepared by the following process. 
The metal salts of the salicylic acid derivative represented by the formula 
(1) of the invention, for example, the alkali metal salts such as sodium, 
potassium and lithium salt can be usually prepared by reacting the 
salicylic acid derivative of the formula (1) with an aqueous solution of 
alkali metal hydroxide, alkali metal carbonate and alkali metal hydrogen 
carbonate such as sodium hydroxide, potassium hydroxide, lithium 
hydroxide, sodium carbonate, potassium carbonate and sodium hydrogen 
carbonate. 
In the metal salt of the salicylic acid derivative of the formula (1), the 
salt of metals having 2, 3 and 4 valence is a novel compound. Such 
polyvalent metal salt of the salicylic acid derivative is difficultly 
soluble or insoluble in water and usually prepared by a double 
decomposition reaction of an aqueous solution of the alkali metal salt of 
the salicylic acid derivative represented by the formula (1) with an 
aqueous solution of corresponding water soluble compound of metal having 
2, 3 or 4 valence. The double decomposition reaction can be carried out by 
heating or in the presence of a solvent. 
In the double decomposition, the aqueous solution of the alkali metal salt 
of the salicylic acid derivative represented by the formula (1) can also 
be used by mixing two or more aqueous solutions individually containing an 
alkali metal salt of a different salicylic acid derivative represented by 
the formula (1). 
For example, a mixture of aqueous solutions individually containing 
alkali-metal 4-(n-butyloxycarbonylamino)salicylate and alkali-metal 
4-(n-octyloxycarbonylamino)salicylate, or a mixture of aqueous solutions 
individually containing alkali-metal 4-(phenyloxycarbonylamino)salicylate 
and alkali-metal 5-(cyclohexyloxycarbonylamino)salicylate can also be used 
in the invention for the preparation of metal salts having 2, 3 or 4 
valence. The mixture of the polyvalent metal salts thus prepared can be 
suitably used for the electron accepting compound of the heat-sensitive 
recording material of the invention. 
The above water soluble metal compounds include, for example, zinc sulfate, 
magnesium sulfate, calcium sulfate, aluminum sulfate and other sulfates; 
zinc chloride, magnesium chloride, calcium chloride, barium chloride, 
nickel chloride, cobalt chloride, aluminum chloride and other chlorides; 
and zinc acetate, manganese acetate and other acetates. 
The metal salt of the salicylic acid derivative which is prepared as above 
sometimes forms solvate such as hydrate depending upon preparation 
conditions. The solvate is also suitable as the electron accepting 
compound in the heat-sensitive recording material of the invention. The 
solvate can of course be desolvated by known means such as drying to 
prepare the metal salt of the salicylic acid derivative which does not 
contain water or other solvents. Such a desolvated metal salt of the 
salicylic acid derivative can of course be used for the electron accepting 
compound in the heat-sensitive recording material of the invention. 
The heat-sensitive recording material of the invention is prepared as 
illustrated below by using the above salicylic acid derivative of the 
formula (1) and/or the metal salt of said derivative for the electron 
accepting compound. 
The salicylic acid derivative represented by the formula (1) and the metal 
salt of the salicylic acid derivative can be used singly or as a mixture 
of the derivative, a mixture of the metal salt of said derivative, or a 
mixture of the derivative and the metal salt of said derivative. 
In the heat-sensitive recording material of the invention, the salicylic 
acid derivative of the formula (1) and/or the metal salt of said 
derivative are used as the electron accepting compound. The electron 
accepting compound and the color forming, electron donating compound are 
used in an amount of usually from 50 to 700 parts by weight, preferably 
from 100 to 500 parts by weight of the electron accepting compound 
(salicylic acid derivative and/or the metal salt thereof) for 100 parts by 
weight of the electron donating compound. 
The color forming, electron donating compounds which are colorless or pale 
colored and can be used for the heat-sensitive recording material of the 
invention include, for example, triarylmethane compounds, diarylmethane 
compounds, rhodamine-lactam compounds, fluoran compounds, indolylphthalide 
compounds, pyridine compounds, spiro compounds and fluorene compounds. 
Practical electron donating compounds will be illustrated below. 
The triarylmethane compounds include, for example, 
3,3-bis(4-dimethylaminophenyl)-6-dimethylaminophthalide [crystal violet 
lactone], 3,3-bis(4-dimethylaminophenyl)phthalide, 
3-(4-dimethylaminophenyl)-3-(1,3-dimethylindol-3-yl)phthalide, 
3-(4-dimethylaminophenyl)-3-(2-methylindol-3-yl)phthalide, 
3,3-bis(9-ethylcarbazole-3-yl)-6-dimethylaminophthalide, 
3-(4-dimethylaminophenyl)-3-(1-methylpyrrol-3-yl)-6-dimethylaminophthalide 
, and 
3,3-bis[2,2-bis(4-dimethylaminophenyl)ethenyl-4,5,6,7-tetrachlorophthalide 
Diarylmethane compounds include, for example, 
4,4-bis-dimethylaminobenzhydrin benzyl ether, N-halophenylleucoauramine, 
and N-2,4,5-trichlorophenylleucoauramine. 
Rhodamine-lactam compounds include, for example, rhodamine-B-anilinolactam, 
rhodamine-(4-nitroanilino)lactam, and rhodamine-B-(4-chloroanilino)lactam. 
Fluoran compounds include, for example, 3,6-dimethoxyfluoran, 
3-dimethylamino-7-methoxyfluoran, 3-diethylamino-6-methoxyfluoran, 
3-diethylamino-7-methoxyfluoran, 3-diethylamino-7-chlorofluoran, 
3-diethylamino-6-methyl-7-chlorofluorane, 
3-diethylamino-6,7-dimethylfluoran, 
3-N-cyclohexyl-N-n-butylamino-7-methylfluoran, 
3-diethylamino-7-dibenzylaminofluoran, 3-diethylamino-7-octylaminofluoran, 
3-diethylamino-7-di-n-hexylaminofluoran, 3-diethylamino-7-anilinofluoran, 
3-diethylamino-7-(2-chloroanilino)fluoran, 
3-diethylamino-7-(3-chloroanilino)fluoran, 
3-diethylamino-7-(2,3-dichloroanilino)fluoran, 
3-diethylamino-7-(3-trifluoromethylanilino)fluoran, 
3-di-n-butylamino-7-(2-chloroanilino)fluoran, 
3-diethylamino-6-chloro-7-anilinofluoran, 
3-di-n-butylamino-6-chloro-7-anilinofluoran, 
3-diethylamino-6-methoxy-7-anilinofluoran, 
3-di-n-butylamino-6-ethoxy-7-anilinofluoran, 
3-pyrrolidino-6-methyl-7-anilinofluoran, 
3-morpholino-6-methyl-7-anilinofluoran, 
3-dimethylamino-6-methyl-7-anilinofluoran, 
3-diethylamino-6-methyl-7-anilinofluoran, 
3-di-n-butylamino-6-methyl-7-anilinofluoran, 
3-di-n-pentylamino-6-methyl-7-anilinofluoran, 
3-di-n-octylamino-6-methyl-7-anilinofluoran, 
3-N-ethyl-N-methylamino-6-methyl-7-anilinofluoran, 
3-N-n-propyl-N-methylamino-6-methyl-7-anilinofluoran, 
3-N-n-propyl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-isopropyl-N-methylamino-6-methyl-7-anilinofluoran, 
3-N-n-butyl-N-methylamino-6-methyl-7-anilinofluoran, 
3-N-n-butyl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-n-butyl-N-n-propylamino-6-methyl-7-anilinofluoran, 
3-N-isobutyl-N-methylamino-6-methyl-7-anilinofluoran, 
3-N-isobutyl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-isopentyl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-n-hexyl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-n-octyl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-cyclohexyl-N-methylamino-6-methyl-7-anilinofluoran, 
3-N-cyclohexyl-N-n-propylamino-6-methyl-7-anilinofluoran, 
3-N-cyclohexyl-N-n-butylamino-6-methyl-7-anilinofluoran, 
3-N-cyclohexyl-N-n-pentylamino-6-methyl-7-anilinofluoran, 
3-N-cyclohexyl-N-n-hexylamino-6-methyl-7-anilinofluoran, 
3-N-cyclohexyl-N-n-heptylamino-6-methyl-7-anilinofluoran, 
3-N-cyclohexyl-N-n-octylamino-6-methyl-7-anilinofluoran, 
3-N-cyclohexyl-N-n-decylamino-6-methyl-7-anilinofluoran, 
3-N-2'-methoxyethyl-N-methylamino-6-methyl-7-anilinofluoran, 
3-N-2'-methoxyethyl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-2'-methoxyethyl-N-isobutylamino-6-methyl-7-anilinofluoran, 
3-N-2'-ethoxyethyl-N-methylamino-6-methyl-7-anilinofluoran, 
3-N-2'-ethoxyethyl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-3'-methoxypropyl-N-methylamino-6-methyl-7-anilinofluoran, 
3-N-3'-methoxypropyl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-3'-ethoxypropyl-N-methylamino-6-methyl-7-anilinofluoran, 
3-N-3'-ethoxypropyl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-2'-tetrahydrofurfuryl-N-ethylamino-6-methyl-7-anilinofluoran, 
3-N-(4'-methylphenyl)-N-ethylamino-6-methyl-7-anilinofluoran, 
3-diethylamino-6-ethyl-7-anilinofluoran, 
3-diethylamino-6-methyl-7-(3'-methylphenylamino)fluoran, 
3-diethylamino-6-methyl-7-(2',6'-dimethylphenylamino)fluoran, 
3-di-n-butylamino-6-methyl-7-(2',6'-dimethylphenylamino)fluoran, 
3-di-n-butylamino-7-(2',6'-dimethylphenylamino)fluoran, 
2,2-bis[4'-(3-N-cyclohexyl-N-methylamino-6-methylfluoran-7-yl-aminophenyl] 
propane, and 
3-[4'-(4-phenylaminophenyl)aminophenyl]amino-6-methyl-7-chlorofluoran. 
Indolylphthalide compounds include, for example, 
3,3-bis(1-ethyl-2-methylindole-3-yl)phthalide, 
3,3-bis(1-octyl-2-methylindole-3-yl)phthalide, 
3-(2-ethoxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindole-3-yl)phthalide 
, 3-(2-ethoxy-4-dibutylaminophenyl)-3-(1-ethyl-2-methylindole-3-yl) 
phthalide, and 
3-(2-ethoxy-4-diethylaminophenyl)-3-(1-octyl-2-methylindole-3-yl) 
phthalide. 
Pyridine compounds include, for example, 
3-(2-ethoxy-4-diethylaminophenyl)-3-(1-octyl-2-methylindole-3-yl)-4 or 
7-azaphthalide, 
3-(2-ethoxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindole-3-yl)-4 or 
7-azaphthalide, 
3-(2-hexyloxy-4-diethylaminophenyl)-3-(1-ethyl-2-methylindole-3-yl)-4 or 
7-azaphthalide, 
3-(2-ethoxy-4-diethylaminophenyl)-3-(1-ethyl-2-phenylindole-3-yl)-4 or 
7-azaphthalide, and 
3-(2-butoxy-4-diethylaminophenyl)-3-(1-ethyl-2-phenylindole-3-yl)-4 or 
7-azaphthalide. 
Spiro compounds include, for example, 3-methyl-spiro-dinaphthopyran, 
3-ethyl-spiro-dinaphthopyran, 3-phenyl-spiro-dinaphthopyran, 
3-benzyl-spiro-dinaphthopyran, 
3-methyl-naphtho-(3-methoxybenzo)spiropyran, and 
3-propyl-spiro-dibenzopyran. 
Fluorene compounds include, for example, 
3',6',-bis(diethylamino)-5-diethylaminospiro(isobenzofuran-1,9'-fluorene)- 
3-one, and 
3',6',-bis(diethylamino)-7-diethylamino-2-methylspiro(1,3-benzoxazine-4,9' 
-fluorene). 
These color forming, electron donating compounds can be used singly, or as 
a mixture in order to control color tone of developed image or to obtain 
multi-colored heat-sensitive recording materials. 
The heat-sensitive recording material of the invention is characterized by 
comprising as the electron accepting compound one or more salicylic acid 
derivatives of the formula (1) and/or the metal salts of said derivatives. 
Other electron accepting compounds can be simultaneously used in the range 
giving no adverse effect on the desired properties of the heat-sensitive 
recording material of the invention. 
In such a case, the proportion of the salicylic acid derivative represented 
by the formula (1) and/or the metal salt of the derivative in the total 
electron accepting compounds is usually 20% by weight or more, preferably 
40% by weight or more, most preferably 60% by weight or more. 
Other electron accepting compounds which can be used in combination with 
the salicylic acid derivative of the formula (1) and/or the metal salt of 
the derivative include, for example, phenol derivatives, organic acids and 
their metal salts, complexes, urea derivatives and other organic electron 
accepting compounds; and acid clay and other inorganic electron accepting 
compounds. 
Practical examples of preferred electron accepting compounds include 
organic electron accepting compounds such as 4-tert-butylphenol, 
4-tert-octylphenol, 4-phenylphenol, 1-naphthol, 2-naphthol, hydroquinone, 
resorcinol 4-tert-octylcatechol, 2,2'-dihydroxybiphenyl, 
4,4'-dihydroxydiphenyl ether, 2,2-bis(4'-hydroxyphenyl)propane [bisphenol 
A], 1,1-bis(4'-hydroxyphenyl)cyclohexane, 
2,2-bis(4'-hydroxy-3'-methylphenyl)propane, 
1,4-bis(4'-hydroxycumyl)benzene, 1,3,5-tris(4'-hydroxycumyl)benzene, 
4,4-(m-phenylenediisopropylidene)bisphenol, 
4,4-(p-phenylenediisopropylidene)bisphenol, ethyl 
2,2-bis(4'-hydroxyphenyl)acetate, n-butyl 
4,4-(4'-hydroxyphenyl)pentanoate, benzyl 4-hydroxybenzoate, phenethyl 
4-hydroxybenzoate, phenoxyethyl 2,4-dihydroxybenzoate, dimethyl 
4-hydroxyphthalate, n-propyl gallate, n-octyl gallate, n-dodecyl gallate, 
n-octadecyl gallate, hydroquinone monobenzyl ether, 
bis(3-methyl-4-hydroxyphenyl)sulfide, 
bis(2-methyl-4-hydroxyphenyl)sulfide, bis(3-phenyl-4-hydroxyphenyl)sulfide 
, bis(3-cyclohexyl-4-hydroxyphenyl)sulfide, bis(4-hydroxyphenyl)sulfoxide, 
bis(4-hydroxyphenyl)sulfone, bis-(3-allyl-4-hydroxyphenyl)sulfone, 
2,4'-dihydroxydiphenyl sulfone, 4-hydroxy-4'-methyldiphenyl sulfone, 
4-hydroxy-4'-chlorodiphenyl sulfone, 4-hydroxy-4'-n-propoxydiphenyl 
sulfone, 4-hydroxy-4'-isopropoxydiphenyl sulfone, 
4-hydroxy-4'-n-butoxydiphenyl sulfone, 3,4-dihydroxy-4'-methyldiphenyl 
sulfone, 2,4-dihydroxydiphenyl sulfone, 2-methoxy-4'-hydroxydiphenyl 
sulfone, 2-ethoxy-2'-hydroxydiphenyl sulfone, 
bis(2-hydroxy-5-tert-butylphenyl)sulfone, 
bis(2-hydroxy-5-chlorophenyl)sulfone, 4-hydroxybenzophenone, 
2,4-dihydroxybenzophenone, 1,7-di(4-hydroxyphenylthio)-3,5-dioxaheptane, 
1,5-di(4-hydroxyphenylthio)-3-oxapentane, and other phenol derivatives, 
salicylic acid, 3-isopropylsalicylic acid, 3-cyclohexylsalicylic acid, 
3,5-di-tert-butylsalicylic acid, 3,5-di-.alpha.-methylbenzylsalicylic 
acid, 3-methyl-5-.alpha.-methylbenzylsalicylic acid, 
4-[2'-(4-methoxyphenyloxy)ethyloxy]salicylic acid, 2-hydroxy-3-naphthoic 
acid, 2-hydroxy-6-naphthoic acid, monobenzyl phthalate, monophenyl 
phthalate, 4-nitrobenzoic acid, 3-nitrobenzoic acid, 2-nitrobenzoic acid, 
4-chlorobenzoic acid and other organic acid and metal salts thereof such 
as salts of nickel, zinc, aluminum and calcium, zinc thiocyanate-antipyrin 
complex, molybdenic acid-acetylacetone complex and other complexes, 
phenylthiourea, di(3-trifluoromethylphenyl)thiourea, 
1,4-di(3'-chlorophenyl)-3-thiosemicarbazide and other urea derivatives; 
and inorganic electron accepting compounds such as acid clay, attapulgite, 
activated clay, aluminum chloride, zinc chloride and zinc bromide. 
These electron accepting compounds can be used singly or as a mixture. 
Further, a heat fusible compound which has a melting point of from 
70.degree. to 150.degree. C., preferably from 80.degree. to 130.degree. C. 
can be added as a sensitizer to the heat-sensitive recording material of 
the invention in order to enhance developing sensitivity and conform to 
high speed recording. 
The heat fusible compound is used in an amount of usually from 10 to 700 
parts by weight, preferably from 20 to 500 parts by weight for 100 parts 
by weight of the color forming, electron donating compound. 
Exemplary heat fusible compounds which can be used include capronamide, 
capramide, palmitamide, stearamide, oleamide, stearyl urea, stearanilide, 
N-ethylcarbazole, 4-methoxydiphenylamine and other nitrogen containing 
compounds; benzyl 4-benzyloxybenzoate, phenyl 2-naphthoate, phenyl 
1-hydroxy-2-naphthoate, dibenzyl oxalate, di(4-methylbenzyl)oxalate, 
di(4-chlorobenzyl)oxalate, diphenacyl glutarate, 
di(4-methylphenyl)carbonate, dibenzyl terephthalate and other ester 
compounds; 4-benzylbiphenyl, m-terphenyl, fluorene, fluoranthene, 
2,6-diisopropylnaphthalene, 3-benzylacenaphthene and other hydrocarbon 
compounds; 2-benzyloxynaphthalene, 2-(4'-methylbenzyloxy)naphthalene, 
1,4-diethoxynaphthalene, 1,2-diphenoxyethane, 1,2-bis 
(3'-methylphenoxy)ethane, 1-phenoxy-2-(4'-ethylphenoxy)ethane, 
1-(4'-methoxyphenoxy)-2-phenoxyethane, 
1-(4'-methoxyphenoxy)-2-(3'-methylphenoxy)ethane, 
1-(4'-methoxyphenoxy)-2-(2'-methylphenoxy)ethane, 
4-(4'-methylphenoxy)biphenyl, 1,4-bis(2'-chlorobenzyloxy)benzene, 
4,4'-di-n-butoxydiphenylsulfone, 1,2-diphenoxybenzene, 
1,4-bis(2'-chlorophenoxy)benzene, 1,4-bis(4'-methylphenoxy)benzene, 
1,4-bis(3'-methylphenoxymethyl)benzene, 
4-chlorobenzyloxy-(4'-ethoxybenzene), 4,4'-bis(phenoxy)diphenyl ether, 
4,4'-bis(phenoxy)diphenyl thioether, 1,4-bis(4'-benzylphenoxy)benzene, 
1,4-bis[(4'-methylphenyloxy)methoxymethyl]benzene and other ether 
compounds. 
These heat fusible compounds can be used singly or as a mixture. 
The heat-sensitive recording material of the invention can be prepared by 
known methods without using a specific method. 
Generally, the color-forming, electron donating compound, the salicylic 
acid derivative of the formula (1) and/or the metal salt of the derivative 
and other ingredients are individually pulverized and dispersed in a water 
soluble binder with a ball mill, sand mill, horizontal sand mill, 
attrition mill, colloid mill and other means. The dispersions thus 
obtained have a particle size of usually 3 .mu.m or less, preferably 1.5 
.mu.m or less. The dispersions are successively mixed to prepare coating 
liquid for a recording layer. 
Inorganic metal compounds such as zinc oxide, zinc carbonate, calcium 
carbonate, magnesium carbonate, barium carbonate, barium sulfate, titanium 
oxide, aluminum hydroxide and magnesium hydroxide are sometimes used as 
metal pigments. In some cases, the metal pigments are preferably dispersed 
in combination with the salicylic acid derivative of the formula (1) 
and/or the metal salt of the derivative. The heat-sensitive recording 
materials having the higher storage stability of a developed color image 
can be obtained in these cases. 
Practical examples of the water soluble binders include polyvinyl alcohol, 
sulfonated polyvinyl alcohol, hydroxyethyl cellulose, hydroxypropyl 
cellulose, epichlorohydrin modified polyamide, ethylene-maleic anhydride 
copolymer, styrene-maleic anhydride copolymer, isobutylene maleic 
anhydride copolymer, polyacrylic acid, polyacrylamide, methylol modified 
polyacrylamide, starch derivative, casein, gelatin, methylcellulose, 
carboxymethylcellulose, gum arabic and carboxyl modified polyvinyl 
alcohol. 
Further, pigments, water insoluble binders, metallic soaps, wax, 
surfactants, ultraviolet absorbers, hindered phenols and anti-foaming 
agents are added, if desired, in the recording layer of the heat-sensitive 
recording material of the invention. 
Exemplary pigments include zinc oxide, zinc carbonate, calcium carbonate, 
magnesium carbonate, barium carbonate, barium sulfate, titanium dioxide, 
talc, agalmatolite, kaolin, diatomaceous earth, aluminum hydroxide, 
magnesium hydroxide, alumina, silica, amorphous silica, urea-formaldehyde 
filler, polyethylene particulate and cellulose filler. 
Synthetic rubber latex and synthetic resin emulsion such as 
styrene-butadiene rubber latex, acrylonitrile-butadiene rubber latex, 
methyl acrylate-butadiene rubber latex and polyvinyl acetate emulsion are 
generally known as water insoluble binders, and can also be used, if 
desired. 
Metallic soaps which can be used are metal salts of higher fatty acids and 
include, for example, zinc stearate, calcium stearate, aluminum stearate 
and zinc oleate. 
Exemplary wax includes, paraffin wax, microcrystalline wax, carboxy 
modified paraffin wax, carnauba wax, polyethylene wax, polystyrene wax, 
candelilla wax, montane wax and higher fatty acid esters. 
Exemplary surfactants include alkali metal salts of sulfosuccinic acid such 
as sodium di(n-hexyl)sulfosuccinate and sodium 
di(2-ethylhexyl)sulfosuccinate, and fluorine-containing surfactants. 
Exemplary ultraviolet absorbers include cinnamic acid derivatives, 
benzophenone derivatives and benzotriazolylphenol derivatives. 
Hindered phenols are preferably phenol derivatives having a branched alkyl 
group on one or more ortho-positions to a phenolic hydroxyl group. 
Exemplary hindered phenols include: 
1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)butane, 
1,1,3-tris(2-methyl-4-hydroxy-5-cyclohexylphenyl)butane, 
1,1,3-tris(2-ethyl-4-hydroxy-5-tert-butylphenyl)butane, 
1,1,3-tris(3,5-di-tert-butyl-4-hydroxyphenyl)butane, 
1,1,3-tris(2-methyl-4-hydroxy-5-tert-butylphenyl)propane, 
2,2'-methylene-bis(6-tert-butyl-4-methylphenol), 
2,2'-methylene-bis(6-tert-butyl-4-ethylphenol), 
1,3,5-trimethyl-2,4,6-tris(3,5-di-tert-butyl-4-hydroxybenzyl)benzene, 
1,3,5-tris(4-tert-butyl-3-hydroxy-2,6-dimethylbenzyl)-isocyanuric acid, 
1,3,5-tris(4-tert-butyl-3-hydroxy-2-methyl-6-ethylbenzyl)-isocyanuric 
acid, and bis(2-methyl-4-hydroxy-5-tert-butylphenyl)sulfide. 
No particular restriction is imposed upon the preparation method of the 
recording layer in the heat-sensitive recording material of the invention. 
Conventionally known techniques can be used. 
For example, the coating liquid of the heat-sensitive recording layer is 
applied on a substrate with a suitable coating device such as an air knife 
coater, blade coater, bar coater, gravure coater, curtain coater and wire 
bar, and successively dried to form a recording layer. 
No particular limitation is placed on the amount of the coating liquid. The 
amount is usually from 1.5 to 12 g/m.sup.2, preferably from 2.5 to 10 
g/m.sup.2 on dry weight. 
The substrate which can be used is paper, plastic sheet and synthetic 
paper. 
If desired, a protective layer can be furnished on the surface and/or the 
back side of the heat-sensitive recording layer, or an undercoating layer 
can of course be furnished between the substrate and the heat-sensitive 
recording layer. Tackifying and other known processing techniques can also 
be applied to the preparation of the heat-sensitive recording material in 
the invention. 
The invention will hereinafter be illustrated further in detail by way of 
preparation examples and examples. However, these examples are not to be 
construed to limit the scope of the invention. In these preparation 
examples and examples, percent means percent by weight unless otherwise 
noted. 
PREATION EXAMPLES 1 
Preparation of Compound No. 77 
To 700 ml of methanol suspended 153 g of 4-aminosalicylic acid and 84 g of 
sodium hydrogen carbonate, 193 g of n-octylchloroformate was dropwise 
added over 2 hours at room temperature. After finishing dropwise addition, 
the mixture was further stirred for 2 hours at room temperature. An 
aqueous solution containing 30 g of concentrated hydrochloric acid and 
1200 ml of water was added to the reaction mixture. Precipitated crystals 
were filtered and dried to obtain 300 g of desired 
4-(n-octyloxycarbonylamino)salicylic acid as colorless crystals. Yield was 
97%. 
Melting point was 157-159.degree. C. Mass spectrum (EI): 309(M.sup.+) 
IR absorption spectrum (KBr): 3360, 1720, 1640 and 1620 cm.sup.-1 
Purity of the product was 99% (area ratio) by high performance liquid 
chromatography. 
COMATIVE PREATION EXAMPLE 1 
To an aqueous solution dissolved 153 g of 4-aminosalicylic acid and 170 g 
of sodium hydrogen carbonate in 2200 ml of water, 193 g of 
n-octylchloroformate was dropwise added over 2 hours at room temperature. 
After finishing dropwise addition, the mixture was further stirred for 5 
hours at room temperature. An aqueous solution containing 30 g of 
concentrated hydrochloric acid and 1200 ml of water was added to the 
reaction mixture. Precipitated crystals were filtered and dried to obtain 
148 g of desired 4-(n-octyloxycarbonylamino)salicylic acid as colorless 
crystals. Yield was 48%. 
COMATIVE PREATION EXAMPLE 2 
To 700 ml of butyl acetate suspended with 153 g of 4-aminosalicylic acid 
and 84 g of sodium hydrogen carbonate, 193 g of n-octylchloroformate was 
dropwise added over 2 hours at room temperature. After finishing dropwise 
addition, the mixture was further stirred for 2 hours. Successively, 
inorganic salt was filtered and butyl acetate was distilled from the 
filtrate under reduced pressure to obtain crystals. 
The crystals were analyzed by high performance liquid chromatography and 
found to contain about 10% of unreacted 4-aminosalicylic acid, about 80% 
of desired 4-(n-octyloxycarbonylamino)salicylic acid and about 10% (area 
ratio) of by-product. 
The crude product was purified by an aqueous methanol solution (50:50 v/v). 
As a result, unreacted 4-aminosalicylic acid could be removed, but the 
desired product still contained about 12% (area ratio) of the by-product. 
PREATION EXAMPLES 2.about.28 
Various salicylic acid derivatives represented by the formula (1) were 
prepared by carrying out the same procedures described in Preparation 
Example 1 except that n-octylchloroformate was replaced by chloroformate 
compounds and alcohols which are illustrated in Table 1. 
Any salicylic acid derivatives thus prepared had yield of 96% or more and 
purity of 99% or more. 
TABLE 1 
______________________________________ 
Prep- 
aration 
Exam- Chloroformate Salicylic acid 
ple compound Alcohol derivative 
______________________________________ 
2 methyl- MeOH compound No. 66 
chloroformate mp. 198.about.200.degree. C. 
3 ethyl- MeOH compound No. 67 
chloroformate mp. 208.about.210.degree. C. 
4 n-propyl- MeOH-toluene compound No. 68 
chloroformate 
(20:80) mp. 190.about.192.degree. C. 
5 n-butyl- MeOH--H.sub.2 O 
compound No. 70 
chloroformate 
(80:20) mp. 159.about.161.degree. C. 
6 isobutyl- MeOH compound No. 71 
chloroformate mp. 185.about.186.degree. C. 
7 n-pentyl- MeOH compound No. 73 
chloroformate mp. 166.about.168.degree. C. 
8 n-hexyl- isopropanol compound No. 75 
chloroformate mp. 165.about.167.degree. C. 
9 n-heptyl- isobutanol compound No. 76 
chloroformate mp. 156.about.158 .degree. C. 
10 2-ethylhexyl- 
MeOH compound No. 78 
chloroformate mp. 133.about.135.degree. C. 
11 n-nonyl- MeOH compound No. 79 
chloroformate mp. 157.about.159.degree. C. 
12 n-decyl- MeOH compound No. 80 
chloroformate mp. 158.about.160.degree. C. 
13 n-undecyl- EtOH compound No. 81 
chloroformate mp. 155.about.157.degree. C. 
14 n-dodecyl- MeOH compound No. 82 
chloroformate mp. 156.about.159.degree. C. 
15 n-tetradecyl- 
MeOH compound No. 84 
chloroformate mp. 155.about.157.degree. C. 
16 n-hexadecyl- 
methyl- compound No. 86 
chloroformate 
cellosolve mp. 153.about.155.degree. C. 
17 cyclohexyl- MeOH compound No. 90 
chloroformate mp. 199.about.202.degree. C. 
18 2-methoxyethyl- 
MeOH compound No. 96 
chloroformate mp. 160.about.163.degree. C. 
19 2-n-hexyloxy- 
MeOH compound No. 97 
ethyl- mp. 120.about.123.degree. C. 
chloroformate 
20 2-phenoxyethyl- 
MeOH compound No. 105 
chloroformate mp. 186.about.189.degree. C. 
21 2-(4'-methoxy- 
MeOH compound No. 107 
phenyl)oxy- mp. 192.about.194.degree. C. 
ethylchloro- 
formate 
22 benzyl- MeOH compound No. 115 
chloroformate mp. 187.about.189.degree. C. 
23 phenyl- MeOH--AcOEt compound No. 119 
chloroformate 
(20:80) p. 208.about.209.degree. C. 
24 4-phenylphenyl- 
MeOH compound No. 123 
chloroformate mp. 221.about.224.degree. C. 
25 4-cumylphenyl- 
MeOH compound No. 131 
chloroformate mp. 202.about.205.degree. C. 
26 4-methoxy- MeOH compound No. 132 
phenyl- mp. 207.about.210.degree. C. 
chloroformate 
27 4-(4' -benzyloxy- 
MeOH compound No. 138 
cumyl)phenyl- mp. 206.about.210.degree. C. 
chloroformate 
28 phenylthiol- 
MeOH compound No. 163 
chloroformate mp. 300.degree. C. 
or more 
______________________________________ 
PREATION EXAMPLE 29 
Preparation of compound No. 188 
To 700 ml of methanol suspended with 153 g of 5-aminosalicylic acid and 84 
g of sodium hydrogen carbonate, 163 g of cyclohexylchloroformate was 
dropwise added over 2 hours at room temperature. After finishing dropwise 
addition, the mixture was further stirred for an hour at room temperature. 
Successively, an aqueous solution containing 30 g of concentrated 
hydrochloric acid and 1200 ml of water was added to the reaction mixture. 
Precipitated crystals were filtered and dried to obtain 269 g of desired 
5-(cyclohexyloxycarbonylamino)salicylic acid as colorless crystals. 
Yield was 96%. Melting point was 260.about.262.degree. C. 
Purity of the product was 99% (area ratio) by high performance liquid 
chromatography. 
PREATION EXAMPLES 30-54 
Various salicylic acid derivatives represented by the formula (1) were 
prepared by carrying out the same procedures as described in Preparation 
Example 29 except that cyclohexylchloroformate was replaced by 
chloroformate compounds and alcohols which are illustrated in Table 2. 
Any salicylic acid derivatives thus obtained had yield of 96% or more and 
purity of 99% or more. 
TABLE 2 
______________________________________ 
Prep- 
aration 
Exam- Chloroformate Salicylic acid 
ple compound Alcohol derivative 
______________________________________ 
30 methyl- MeOH compound No. 171 
chloroformate mp. 220.about.222.degree. C. 
31 ethyl- EtOH compound No. 172 
chloroformate mp. 214.about.217.degree. C. 
32 n-propyl- MeOH- compound No. 173 
chloroformate 
dichloroethane 
mp. 199.about.202.degree. C. 
(50:50) 
33 n-butyl- MeOH compound No. 174 
chloroformate mp. 194.about.197.degree. C. 
34 iso-butyl isopropanol compound No. 175 
chloroformate mp. 200.about.202.degree. C. 
35 n-pentyl- MeOH compound No. 176 
chloroformate mp. 184.about.186.degree. C. 
36 n-hexyl- n-butanol compound No. 178 
chloroformate mp. 180.about.183.degree. C. 
37 n-heptyl- MeOH- compound No. 179 
chloroformate 
isopropanol mp. 180.about.182.degree. C. 
38 n-octyl- MeOH compound No. 180 
chloroformate mp. 180.about.182.degree. C. 
39 2-ethylhexyl- 
MeOH compound No. 181 
chloroformate mp. 147.about.149.degree. C. 
40 n-nonyl- MeOH compound No. 182 
chloroformate mp. 177.about.180.degree. C. 
41 n-decyl- isopropanol compound No. 183 
chloroformate mp. 179.about.181.degree. C. 
42 n-undecyl- MeOH compound No. 184 
chloroformate mp. 178.about.180.degree. C. 
43 n-dodecyl- MeOH compound No. 185 
chloroformate mp. 176.about.178.degree. C. 
44 n-tetradecyl- 
MeOH compound No. 186 
chloroformate mp. 174.about.176.degree. C. 
45 n-hexadecyl- MeOH compound No. 187 
chloroformate mp. 171.about.173.degree. C. 
46 2-n-hexyloxyethyl- 
MeOH compound No. 195 
chloroformate mp. 202.about.204.degree. C. 
47 2-phenoxyethyl- 
MeOH compound No. 200 
chloroformate mp. 210.about.214.degree. C. 
48 2-(4'-methoxy- 
MeOH compound No. 202 
phenyl)oxyethyl- mp. 198.about.201.degree. C. 
chloroformate 
49 benzyl- MeOH compound No. 208 
chloroformate mp. 248.about.251.degree. C. 
50 phenyl- MeOH compound No. 212 
chloroformate mp. 300.degree. C. 
or more 
51 4-phenylphenyl- 
MeOH compound No. 214 
chloroformate p. 255.about.259.degree. C. 
52 4-cumylphenyl- 
MeOH compound No. 218 
chloroformate mp. 164.about.167.degree. C. 
53 4-methoxyphenyl- 
MeOH compound No. 219 
chloroformate mp. 245.about.250.degree. C. 
54 2,4-dimethyl- 
MeOH compound No. 235 
phenyl mp. 275.about.281.degree. C. 
chloroformate 
______________________________________ 
PREATION EXAMPLE 55 
Preparation of zinc salt of compound No. 70 
To 400 ml of an aqueous solution containing 8.4 g of sodium hydrogen 
carbonate, 25.3 g of 4-(n-butyloxycarbonylamino)salicylic acid was 
gradually added and dissolved at room temperature. The solution obtained 
was dropwise added to 200 ml of an aqueous solution containing 14.9 g of 
zinc sulfate 7 hydrate over 20 minutes at room temperature. After 
finishing dropwise addition, the mixture was further stirred for 30 
minutes. Precipitated crystals were filtered, washed with water, and dried 
to obtain 26 g of desired zinc 4-(n-butyloxycarbonylamino)salicylate. 
Melting point was 140.about.143.degree. C. IR absorption spectrum (KBr): 
1750 and 1630 cm.sup.-1. 
PREATION EXAMPLE 56 
Preparation of zinc salt of compound No. 77 
To a solution containing 8.4 g of sodium hydrogen carbonate, 400 ml of 
water and 600 ml of methanol, 31 g of 4-(n-octyloxycarbonylamino) 
salicylic acid was gradually add and dissolved at room temperature. 
The solution obtained was dropwise added to 1200 ml of an aqueous solution 
containing 14.9 g of zinc sulfate 7 hydrate over an hour at room 
temperature. After finishing dropwise addition, the mixture was further 
stirred for 4 hours at room temperature. Precipitated crystals were 
filtered, washed with water and dried to obtain 33.3 g of desired zinc 
4-(n-octyloxycarbonylamino)salicylate as colorless crystals. 
Melting point was 140.about.143.degree. C. IR absorption spectrum (KBr) of 
the product is illustrated in FIG. 1. 
PREATION EXAMPLE 57 
Preparation of zinc salt of compound No. 80 
Zinc 4-(n-decyloxycarbonylamino)salicylate was prepared by carrying out the 
same procedures as described in preparation example 56 except that 
4-(n-octyloxycarbonylamino)salicylic acid was replaced by 
4-(n-decyloxycarbonylamino)salicylic acid. 
Melting point was 141.about.144.degree. C. IR absorption spectrum (KBr) of 
the product is illustrated in FIG. 2. 
PREATION EXAMPLE 58 
Preparation of zinc salt of compound No. 82 
Zinc 4-(n-dodecyloxycarbonylamino)salicylate was prepared by carrying out 
the same procedures as described in Preparation Example 56 except that 
4-(n-octyloxycarbonylamino)salicylic acid is replaced by 
4-(n-dodecyloxycarbonylamino)salicylic acid. 
Melting point was 130.about.134.degree. C. IR absorption spectrum (KBr): 
1750 and 1630 cm.sup.-1. 
PREATION EXAMPLE 59 
Preparation of zinc salt of compound No. 115 
Zinc 4-(benzyloxycarbonylamino)salicylate was prepared by carrying out the 
same procedures as described in Preparation Example 56 except that 
4-(n-octyloxycarbonylamino)salicylic acid was replaced by 
4-(benzyloxycarbonylamino)salicylic acid. 
Melting point was 300.degree. C. or more. 
PREATION EXAMPLE 60 
Preparation of zinc salt of compound No. 119 
Zinc 4-(phenyloxycarbonylamino)salicylate was prepared by carrying out the 
same procedures as described in Preparation Example 56 except that 
4-(n-octyloxycarbonylamino)salicylic acid is replaced by 
4-(phenyloxycarbonylamino)salicylic acid. 
Melting point was 300.degree. C. or more. IR absorption spectrum (KBr): 
1760 and 1630 cm.sup.-1. 
PREATION EXAMPLE 61 
Preparation of zinc salt of compound No. 188 
Zinc 5-(cyclohexyloxycarbonylamino)salicylate was prepared by carrying out 
the same procedures as described in Preparation Example 56 except that 
4-(n-octyloxycarbonylamino)salicylic acid was replaced by 
5-(cyclohexyloxycarbonylamino)salicylic acid. 
Melting point was 300.degree. C. or more. IR absorption spectrum (KBr): 
1690 and 1640 cm.sup.-1. 
PREATION EXAMPLE 62 
Preparation of zinc salt of compound No. 202 
Zinc 5-[2'-(4-methoxyphenyl)oxyethyloxycarbonylamino]salicylate was 
prepared by carrying out the same procedures as described in Preparation 
Example 56 except that 4-(n-octyloxycarbonylamino) salicylic acid was 
replaced by 5-[2'-(4-methoxyphenyl)oxyethyloxycarbonylamino]salicylic 
acid. 
Melting point was 300.degree. C. or more. 
PREATION EXAMPLE 63 
Preparation of nickel salt of compound No. 77 
Nickel 4-(n-octyloxycarbonylamino)salicylate was prepared by carrying out 
the same procedures as described in Preparation Example 56 except that 
zinc sulfate 7 hydrate was replaced by nickel chloride 6 hydrate. 
Melting point was 300.degree. C. or more. IR absorption spectrum (KBr): 
1710 and 1610 cm.sup.-1. 
PREATION EXAMPLE 64 
Preparation of manganese salt of compound No. 77 
Manganese 4-(n-octyloxycarbonylamino)salicylate was prepared by carrying 
out the same procedures as described in Preparation Example 56 except that 
zinc sulfate 7 hydrate was replaced by manganese acetate hydrate. 
Melting point was 300.degree. C. or more. IR absorption spectrum (KBr): 
1720 and 1600 cm.sup.-1. 
PREATION EXAMPLE 65 
Preparation of cobalt salt of compound No. 77 
Cobalt 4-(n-octyloxycarbonylamino)salicylate was prepared by carrying out 
the same procedures as described in Preparation Example 56 except that 
zinc sulfate 7 hydrate was replaced by cobalt chloride 6 hydrate. 
Melting point was 200.about.205.degree. C. 
PREATION EXAMPLE 66 
Preparation of aluminum salt of compound No. 77 
Aluminum 4-(n-octyloxycarbonylamino)salicylate was prepared by carrying out 
the same procedures as described in Preparation Example 56 except that 
zinc sulfate 7 hydrate was replaced by aluminum chloride. 
Melting point was 190.about.195.degree. C. IR absorption spectrum (KBr): 
1720 and 1630 cm.sup.-1. 
PREATION EXAMPLE 67 
Preparation of magnesium salt of compound No. 188 
To 400 ml of an aqueous solution containing 4.0 g of sodium hydroxide, 27.9 
g of 5-(cyclohexyloxycarbonylamino)salicylic acid was gradually added and 
dissolved at room temperature. The solution thus obtained was dropwise 
added over 20 minutes at room temperature to 200 ml of an aqueous solution 
containing 10.2 g of magnesium chloride 6 hydrate. After finishing 
dropwise addition, the mixture was further stirred for 30 minutes. 
Precipitated crystals were filtered, washed with water and dried to obtain 
28 g of desired magnesium 5-(cyclohexyloxycarbonylamino)salicylate. 
Melting point was 300.degree. C. or more. IR absorption spectrum (KBr): 
1690 and 1630 cm.sup.-1. 
PREATION EXAMPLE 63 
Preparation of calcium salt of compound No. 188 
Calcium 5-(cyclohexyloxycarbonylamino)salicylate was prepared by carrying 
out the same procedures as described in Preparation Example 67 except that 
magnesium chloride 6 hydrate was replaced by calcium chloride. 
Melting point was 300.degree. C. or more. IR absorption spectrum (KBr): 
1690cm.sup.-1. 
PREATION EXAMPLE 69 
Preparation of barium salt of compound No. 188 
Barium 5-(cyclohexyloxycarbonylamino)salicylate was prepared by carrying 
out the same procedures as described in Preparation Example 67 except that 
magnesium chloride 6 hydrate was replaced by barium chloride 2 hydrate. 
Melting point was 300.degree. C. or more. 
PREATION EXAMPLE 70 
Preparation of nickel salt of compound No. 188 
Nickel 5-(cyclohexyloxycarbonylamino)salicylate was prepared by carrying 
out the same procedures as described in Preparation Example 67 except that 
magnesium chloride 6 hydrate was replaced by nickel chloride 6 hydrate. 
Melting point was 300.degree. C. or more. 
The electron accepting compounds of the invention which was obtained in 
Preparation Examples will hereinafter be used for preparing heat-sensitive 
recording paper and the results of evaluating properties of the paper will 
be illustrated as examples. 
In order to prepare heat-sensitive recording paper in each example, the 
components A, B, C and D having the following compositions were 
individually pulverized with a sand grinding mill to prepare dispersion 
having an average particle size of 1.5 .mu.m or less 
______________________________________ 
(Composition of component A) 
______________________________________ 
Color forming, electron donating compound 
10 g 
10% Aqueous polyvinyl alcohol solution 
10 g 
(Kuraray 117) 
Water 80 g 
total 100 g 
______________________________________ 
______________________________________ 
(Composition of component B) 
______________________________________ 
Electron accepting compound 
20 g 
Precipitated calcium carbonate 
40 g 
(Okutama Kogyo, TP-123) 
10% Aqueous polyvinyl alcohol solution 
60 g 
(Kuraray 117) 
Water 130 g 
total 250 g 
______________________________________ 
______________________________________ 
(Composition of component C) 
______________________________________ 
Electron accepting compound 
20 g 
Precipitated calcium carbonate 
10 g 
(Okutama Kogyo, TP-123) 
Zinc oxide 30 g 
10% Aqueous polyvinyl alcohol solution 
60 g 
(Kuraray 117) 
Water 130 g 
total 250 g 
______________________________________ 
______________________________________ 
(Composition of component D) 
______________________________________ 
Heat fusible compound 20 g 
(2-benzyloxynaphthalene) 
10% Aqueous polyvinyl alcohol solution 
10 g 
(Kuraray 117) 
Water 220 g 
total 250 g 
______________________________________ 
Properties of each heat-sensitive recording paper was evaluated by the 
following methods. 
(1) Storage stability test of an uncolored portion 
Whiteness was measured immediately after coating with a color difference 
meter, .SIGMA.-80(Trade mark of Nippon Denshoku Co.) on the uncolored 
portion of each heat-sensitive recording paper which was prepared in the 
examples and comparative examples. 
The heat-sensitive recording paper prepared in Comparative Examples 3, 4 
and 5 was already soiled to gray immediately after coating. The moist heat 
resistance test and the oil resistance test were individually carried out 
and storage stability was evaluated after each test by measuring whiteness 
of the uncolored portion on the heat-sensitive recording paper. 
The moist heat resistance test was carried out by storing each 
heat-sensitive recording paper at 40.degree. C. in 90% relative humidity 
for 24 hours and successively measuring whiteness with a color difference 
meter. The oil resistance test was carried out by superposing a sheet of 
paper coated with capsules containing dioctyl phthalate upon each 
heat-sensitive recording paper, passing through press rolls, storing at 
25.degree. C. for a week and thereafter measuring the whiteness of the 
uncolored portion with a color difference meter. 
A larger value indicates higher whiteness and illustrates excellent storage 
stability of the uncolored portion. 
The writing utensils resistance test was carried out by writing on an 
uncolored portion with a fluorescent pen, allowing to stand at 25.degree. 
C. for 72 hours and then visually observing the whiteness of the uncolored 
portion. 
.largecircle. indicates high whiteness without soil. 
X indicates a dark gray soiled state. 
(2) Storage stability test of a developed image 
A developed color image having color density of 0.6 according to a Macbeth 
reflection densitometer TR-524 was formed on each heat-sensitive recording 
paper by using a color forming apparatus for heat-sensitive recording 
paper, TH-PMD (Trade mark of Okura Denki Co.) 
The storage stability test was carried out by using the image developed 
recording paper thus obtained. The moist heat resistance test and oil 
resistance test were individually carried out and storage stability was 
evaluated by measuring the storage stability of developed color image on 
each recording paper after each test. 
The moist heat resistance test was carried out by storing the image 
developed recording paper at 60.degree. C. in 90% relative humidity for 24 
hours and thereafter measuring the image density with a Macbeth reflection 
densitometer to calculate a residual rate of color image. 
The oil resistance test was carried out by superposing the paper coated 
with capsules containing dioctyl phthalate upon each image developed 
recording paper, passing through press rolls, storing at 25 .degree. C. 
for a week and thereafter measuring the density of color image with a 
Macbeth reflection densitometer to calculate a residual rate of color 
image. 
##EQU1## 
A larger value indicates higher storage stability of developed color image. 
The writing utensils resistance test was carried out by writing on a 
colored portion of each image developed recording paper with a fluorescent 
pen, allowing to stand at 25 .degree. C. for 72 hours and then visually 
observing the residual rate of the colored portion. 
.circleincircle. No color fading was observed. 
.largecircle. A little color fading was observed. 
X Color fading was observed. 
Results are illustrated in Table 7. 
EXAMPLES 1.about.25 
Mixtures composed of 100 g of component A, 250 g of component B, 250 g of 
component D and 23 g of 30% paraffin wax were coated on wood free paper so 
as to obtain dry coating weight of 5.0.+-.0.5 g/m.sup.2 and dried to 
obtain heat-sensitive recording paper. 
Color forming, electron donating compounds in component A and electron 
accepting compounds in component B which were used in these examples are 
illustrated in Table 3. 
Results of the storage stability test on the uncolored portion of resulting 
heat-sensitive recording paper are illustrated in Table 6. Results of the 
storage stability test on the developed color image are illustrated in 
Table 7. 
TABLE 3 
______________________________________ 
Exam- Color forming, Electron 
ple electron donating compound 
accepting compound 
______________________________________ 
1 3-di-n-pentylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 68 
2 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 70 
3 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 76 
4 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 77 
5 3-N-isopentyl-N-ethylamino- 
manganese salt of 
6-methyl-7-anilinofluoran 
compound No. 77 
6 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 79 
7 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 80 
8 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 81 
9 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 82 
10 3-N-isopentyl-N-ethylamino- 
zinc salt of 
6-methyl-7-anilinofluoran 
compound No. 84 
11 3-N-3'-ethoxypropyl-N- 
zinc salt of 
ethylamino-6-methyl-7- 
compound No. 107 
anilinofluoran 
12 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 115 
13 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 119 
14 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 121 
15 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 123 
16 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 124 
17 3-N-n-propyl-N- zinc salt of 
methylamino-6-methyl- 
compound No. 131 
7-anilinofluoran 
18 3-N-isobutyl-N-methylamino- 
zinc salt of 
6-methyl-7-anilinofluorane 
compound No. 151 
19 3-N-2'-methoxyethyl-N- 
zinc salt of 
isobutylamino-6-methyl-7- 
compound No. 163 
7-anilinofluoran 
20 3-N-isopentyl-N-ethylamino- 
zinc salt of 
6-methyl-7-anilinofluorane 
compound No. 181 
21 3-N-isopentyl-N-ethylamino- 
zinc salt of 
6-methyl-7-anilinofluorane 
compound No. 188 
22 3-di-n-butylamino-6-methyl- 
magnesium salt of 
7-anilinofluoran compound No. 188 
23 3-di-n-butylamino-6-methyl- 
nickel salt of 
7-anilinofluoran compound No. 188 
24 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 202 
25 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 77 (50%) 
+ 
compound No. 119 (50%) 
______________________________________ 
EXAMPLES 26.about.31 
Mixtures composed of 100 g of component A, 250 g of component C, 250 g of 
component D and 23 g of 30% paraffin wax were coated on wood free paper so 
as to obtain dry coating weight of 5.0.+-.0.5 g/m.sup.2 and dried to 
obtain heat-sensitive recording paper. 
Color forming, electron donating compounds in component A and electron 
accepting compounds in component C which were used in these examples are 
illustrated in Table 4. 
Results of the storage stability test on the uncolored portion of resulting 
heat-sensitive recording paper are illustrated in Table 6. Results of the 
storage stability test on the developed color image are illustrated in 
Table 7. 
TABLE 4 
______________________________________ 
Color forming, Electron 
Example electron donating compound 
accepting compound 
______________________________________ 
26 3-di-n-butylamino-6-methyl- 
compound No. 70 
7-anilinofluoran 
27 3-di-n-butylamino-6-methyl- 
zinc salt of 
7-anilinofluoran compound No. 77 
28 3-di-n-pentylamino-6-methyl- 
compound No. 79 
7-anilinofluoran 
29 3-di-n-butylamino-6-methyl- 
compound No. 80 
7-anilinofluoran 
30 3-dimethylamino-6-methyl- 
compound No. 119 
7-anilinofluoran 
31 3-di-n-butylamino-6-methyl- 
compound No. 125 
7-anilinofluoran 
______________________________________ 
COMATIVE EXAMPLES 1.about.8 
Mixtures composed of 100 g of component A, 250 g of component B, 250 g of 
component D and 23 g of 30% paraffin wax were coated on wood free paper so 
as to obtain dry coating weight of 5.0.+-.0.5 g/m.sup.2 and dried to 
obtain heat-sensitive recording paper. 
Color forming, electron donating compounds in component A and electron 
accepting compounds in component B which were used in these comparative 
examples are illustrated in Table 5. 
Results of the storage stability test on the uncolored portion of resulting 
heat-sensitive recording paper are illustrated in Table 6. Results of the 
storage stability test on the developed color image are illustrated in 
Table 7. 
TABLE 5 
______________________________________ 
Comparative 
Color forming, Electron 
Example electron donating compound 
accepting compound 
______________________________________ 
1 3-di-n-butylamino-6-methyl- 
bisphenol A 
7-anilinofluoran 
2 3-di-n-butylamino-6-methyl- 
benzyl 
7-anilinofluoran 4-hydroxybenzoate 
3 3-N-isopentyl-N-ethylamino- 
zinc 3,5-di-tert- 
6-methyl-7-anilinofluoran 
butylsalicylate 
4 3-N-isobutyl-N-methylamino- 
zinc 3,5-di(.alpha.- 
6-methyl-7-anilinofluoran 
methylbenzyl)- 
salisylate 
5 3-di-n-butylamino-6-methyl- 
zinc 4-n-hexyl- 
7-anilinofluoran oxysalicylate 
6 3-di-n-butylamino-6-methyl- 
zinc 4-n-phenyl- 
7-anilinofluoran acetylamino- 
salicylate 
7 3-di-n-butylamino-6-methyl- 
zinc 4-benzoyl- 
7-anilinofluoran aminosalicylate 
8 3-di-n-butylamino-6-methyl- 
zinc 4-n-octyl- 
7-anilinofluoran carbonylamino- 
salicylate 
______________________________________ 
TABLE 6 
______________________________________ 
Whiteness after test 
Whiteness Moist 
Recording 
before heat Oil Writing utensils 
paper test resistance 
resistance 
resistance 
______________________________________ 
Example 
1 82.8 81.5 81.6 .largecircle. 
2 82.8 81.6 81.5 .largecircle. 
3 82.7 81.5 81.7 .largecircle. 
4 82.8 81.6 81.5 .largecircle. 
5 82.7 81.5 81.5 .largecircle. 
6 82.7 81.6 81.5 .largecircle. 
7 82.7 81.6 81.6 .largecircle. 
8 82.8 81.5 81.7 .largecircle. 
9 82.7 81.5 81.6 .largecircle. 
10 82.8 81.6 81.5 .largecircle. 
11 82.7 81.5 81.7 .largecircle. 
12 82.7 81.5 81.5 .largecircle. 
13 82.7 81.5 81.6 .largecircle. 
14 82.7 81.5 81.6 .largecircle. 
15 82.8 81.5 81.7 .largecircle. 
16 82.7 81.6 81.6 .largecircle. 
17 82.8 81.5 81.7 .largecircle. 
18 82.7 81.6 81.6 .largecircle. 
19 82.2 81.1 81.3 .largecircle. 
20 82.2 81.0 81.2 .largecircle. 
21 82.1 81.6 81.6 .largecircle. 
22 82.1 81.6 81.6 .largecircle. 
23 82.0 81.4 81.4 .largecircle. 
24 82.1 81.6 81.6 .largecircle. 
25 82.8 81.5 81.7 .largecircle. 
26 82.7 81.5 81.6 .largecircle. 
27 82.6 81.6 81.6 .largecircle. 
28 82.7 81.5 81.6 .largecircle. 
29 82.6 81.5 81.6 .largecircle. 
30 82.7 81.5 81.6 .largecircle. 
31 82.7 81.5 81.6 .largecircle. 
Comparative 
Example 
1 82.7 81.5 81.5 X 
2 82.6 81.3 81.3 X 
3 75.5 58.1 7.7 X 
4 75.5 59.3 6.8 X 
5 77.5 64.2 15.2 X 
6 80.5 79.2 78.2 .largecircle. 
7 79.7 77.3 77.3 .largecircle. 
8 80.0 78.6 78.3 .largecircle. 
______________________________________ 
TABLE 7 
______________________________________ 
Residual rate of developed color image 
(%) 
Recording Moist heat Oil Writing utensils 
paper resistance resistance 
resistance 
______________________________________ 
Example 
1 98 97 .circleincircle. 
2 98 98 .circleincircle. 
3 97 97 .circleincircle. 
4 99 98 .circleincircle. 
5 94 93 .circleincircle. 
6 98 98 .circleincircle. 
7 99 98 .circleincircle. 
8 98 98 .circleincircle. 
9 95 97 .circleincircle. 
10 93 97 .circleincircle. 
11 94 95 .circleincircle. 
12 98 98 .circleincircle. 
13 99 98 .circleincircle. 
14 99 98 .circleincircle. 
15 99 97 .circleincircle. 
16 98 98 .circleincircle. 
17 99 98 .circleincircle. 
18 97 98 .circleincircle. 
19 96 96 .circleincircle. 
20 95 94 .circleincircle. 
21 94 95 .circleincircle. 
22 94 95 .circleincircle. 
23 94 95 .circleincircle. 
24 94 95 .circleincircle. 
25 99 98 .circleincircle. 
26 98 97 .circleincircle. 
27 100 100 .circleincircle. 
28 95 96 .circleincircle. 
29 98 98 .circleincircle. 
30 98 97 .circleincircle. 
31 98 97 .circleincircle. 
Comparative 
Example 
1 15 10 X 
2 11 9 X 
3 97 97 .largecircle. 
4 96 98 .largecircle. 
5 97 98 .largecircle. 
6 32 57 .largecircle. 
7 16 21 .largecircle. 
8 15 59 .largecircle. 
______________________________________ 
As clearly seen in Table 6 and Table 7, the heat-sensitive recording 
material of the invention which was prepared by using the salicylic acid 
derivative represented by the formula (1) and/or the metal salt of said 
derivative as electron accepting compounds is very excellent in storage 
stability(moist heat resistance, oil resistance and writing utensils 
resistance) of the uncolored portion and developed color image as compared 
with a heat-sensitive recording material prepared by using conventional 
electron accepting compounds. 
EXAMPLE 32 
Color forming characteristic test against temperature 
Color forming characteristics against temperature of the heat-sensitive 
recording paper prepared in Examples 2, 3, 4, 6, 7, 8, 9, 24, 27 and 29 
were compared with the heat-sensitive recording paper prepared in 
Comparative Examples 6, 7 and 8. 
Color forming characteristic test against temperature was carried out by 
bringing each heat-sensitive recording paper into contact for 5 seconds 
with a metal block which was previously heated to a prescribed 
temperature. The color density of the image thus developed was measured 
with a Macbeth reflection densitometer. Results are illustrated in Table 
8. A larger value indicates higher color density. 
TABLE 8 
______________________________________ 
Recording Temperature (.degree.C.) 
paper 90 95 100 110 120 
______________________________________ 
Example 
2 0.07 0.23 0.55 1.15 1.33 
3 0.06 0.20 0.61 1.27 1.32 
4 0.07 0.24 0.55 1.20 1.33 
6 0.06 0.20 0.57 1.15 1.34 
7 0.06 0.20 0.65 1.27 1.32 
8 0.07 0.20 0.63 1.19 1.32 
9 0.06 0.22 0.62 1.12 1.33 
24 0.06 0.22 0.59 1.14 1.32 
27 0.07 0.24 0.58 1.18 1.32 
29 0.06 0.21 0.56 1.22 1.33 
Comparative 
Example 
6 0.06 0.08 0.10 0.18 0.35 
7 0.06 0.10 0.18 0.30 0.48 
8 0.07 0.10 0.18 0.35 0.60 
______________________________________ 
As clearly illustrated in Table 8, the heat-sensitive recording material of 
the invention can quickly develop color image at lower temperatures as 
compared with heat-sensitive recording materials in which metal salts of 
conventionally known salicylic acid derivatives having an amide 
substituent are used as electron accepting compounds, and is suitable for 
high speed recording.