GB2196137A

GB2196137A - Recording materials

Info

Publication number: GB2196137A
Application number: GB08709016A
Authority: GB
Inventors: Masakichi Yahagi; Takeo Obitsu; Yutaka Ohnishi; Shinjhi Yoshinaka; Kousaku Morita; Minoru Koguchi
Original assignee: Shin Nisson Kako Co Ltd
Current assignee: Shin Nisson Kako Co Ltd
Priority date: 1986-10-09
Filing date: 1987-04-15
Publication date: 1988-04-20
Also published as: DE3712970A1; GB8709016D0

Description

GB2196137A 1

SPECIFICATION

Recording materials FIELD OF THE INVENTION 5

This invention relates to recording materials, which are predominantly used for reading by instruments. More particularly, the invention relates to recording materials which are effectively used in operating record reading devices responsive to electromagnetic waves ranging from the long-wavelength region of visible light to near infrared region. The recording materials fully comply with the demand arising from the latest development of information control systems. 10 BACKGROUND OF THE INVENTION

With the progress of recent developments of both electronics and information control sys- tems, there is a trend that record reading devices responsive to electromagnetic waves ranging from the long-wavelength region of visible light to near-infrared ray regions have come to be 15 widely used. Under the circumstances, there have been made various proposals on chromogenic dyes which are normally colorless but form dyes absorbing electromagnetic waves in the above mentioned range on contact with acidic substances. Phthalide type compounds are known as the, compounds having such properties as mentioned above, from Japanese Patent LOP Pubin. Nos.

121035/1976, 121037/1976, 121038/1976, 115448/1980, 115449/1980, 115450/1980, 20 115451/1980, 115452/1980, 115456/1980, 167979/1982, 157779/1983, 8364/1985 and 27589/1985. Thiofluoran type compounds are also known from Japanese Patent LOP Publn. No.

148695/1984, and fluorene type compounds are known from Japanese Patent LOP Publn. No.

199757/1984 and European Patent Laid-Open-to-Pubin. No. 124377. Furthermore, we have filed a patent application (as Japanese Patent Application No. 126149/1985) for fluoran compounds 25 capable of forming dyes having the above-mentioned wavelength absorption range.

SUMMARY OF THE INVENTION

Thus, the subject of the invention is to find the materials which form dyes having the above- mentioned wavelength absorption range, from those having far simpler structure than the ma- 30 terials known as so-called chromogenic dyes of the phthalide, fluorene or fluoran type.

BRIEF DESCRIPTION OF THE DRAWINGS

Figure 1 is a reflection curve of the color of the compound No. 4 in Table 1 below developed with clay. 35 Figure 2 is a reflection curve of the color of the compound No. 8 in Table 1 below. In both Figs. 1 and 2, the curve "a" shows a reflection curve as measured 1 hour after color develop ment operation and the curve "b" shows a reflection curve as measured 24 hours after color development operation.

Figure 3 is reflection curves of the developed colors of the recording papers prepared in 40 Examples 6-9, wherein the curves (a), (b), (c) and (d) are reflection curves of the developed colors of the heat-sensitive recording papers (1), (11), (111) and (IV), respectively.

Figure 4 is a reflection curve of the developed color of the recording paper prepared in Example 14.

Figure 5 is reflection curves of the developed colors of the recording papers prepared in 45 Examples 16 and 17, wherein the curves (a), (b), (c) and (d) are reflection curves of the developed colors of the heat-sensitive recording papers (IX), (X), (XI) and (XII), respectively.

DETAILED DESCRIPTION OF THE INVENTION

We have accomplished the present invention on the basis of such unexpected findings that 50 phenylenediamine or naphthylenediamine derivatives represented by the undermentioned formula (1) develop colours on intimate contact with acidic substances and the developed colors absorb electromagnetic waves ranging from the long-wavelength region of visible light to near-infrared region, and further that such color development of the phenylenediamine or naphthylenediamine derivatives will also occur by the action of organohalogen compounds generating halogen radi- 55 cals under the influence of heat and/or light, or by the action of electron acceptable substances capable of forming charge transfer complexes. The present invention provides a recording ma terial which comprises a developer and a phenylenediamine or naphthylenediamine derivative represented by the formula I 2 GB2196137A 2 N 1 n N -(D I 1 5 R ' wherein A, B and C are independently a benzene or naphthalene ring, each of wbich may have at least one substituent which is halogen, cyano, hydroxy], alkyl, aryl, alkoxy, aryloxy, arylalkoxy, alkylcarbonyloxy, arylcarbonyloxy, amino, alkyl-substituted amino, pyrrolidino, piperidino, ary]- 10 substituted amino, or carbamoyl which may be substituted with alkyl or ary], and and R and R', which may be the same or different, are each hydrogen, lower alkyl, aryl or aralkyl.

The recording materials comprise the phenylenediamine or naphthylenediamine derivatives represented by the formula (1) and the above-mentioned various substances which react with said derivatives to develop colors, wherein the color development will occur by such reaction 15 - over the region of from the long-wavelength of visible light to nearinfrared rays. By the term 11 color development- as referred to herein is meant the formation of substances which absorb the electromagnetic waves in the aforementioned wavelength range.

Examples of substituents are recited below, which may be present in the compounds repre- sented by the formula (1). Of the substituents linking to the ring A, ring B and ring C, the alkyl 20 moiety in the alkyl, alkylcarbonyloxy and alkyl-substituted amino and alkyl-substituted carbamoyl linking directly to said 3 rings is preferably of 1 to 8 carbon atoms which may be branched or substituted; the alkoxy moiety in the alkoxy and arylalkoxy linking directly to said 3 rings is preferably of 1 to 5 carbon atoms which may be branched; the aryl moiety in the aryl, aryloxy, arylcarbonyloxy and aryl-substituted amino and aryl-substituted carbamoyl linking directly to said 25 3 rings is peferably phenyl and/or naphthyl which may be substituted with at least one substituent selected from the group consisting of alkyl having 1 to 5 carbon atoms which may be branched, alkoxy having 1 to 5 carbon atoms which may be branched, amino which may be substituted with at least one alkyl of 1 to 5 carbon atoms which may be branched; halogen atom and hydroxy]. The lower alkyl represented by R and R' is preferably of 1 to 5 carbon 30 atoms which may be branched or substituted, and the aryl represented by R and R' is phenyl or/and naphthyl which may be substituted with at least one substituent selected from the group consisting of alkyl having 1 to 5 carbon atoms which may be branched, alkoxy having 1 to 5 carbon atoms which may be branched, amino which may be substituted with alkyl having 1 to 5 carbon atoms which may be branched, halogen atom or hydroxyl, and the aralkyl represented by 35 R and R' of 1 to 3 carbon atoms linked to phenyl, said phenyl may be substituted with at least one substituent selected from the group consisting of alkyl having 1 to 5 carbon atoms which may be branched, alkoxy having 1 to 5 carbon atoms which may be branched, amino which may be substituted with alkyl having 1 to 5 carbon atoms which may be branched, halogen atom or hydroxyl. 40 Some- of the compounds mentioned above are shown in Table 1 with regard to their melting points and maximum absorption wavelengths of their colors developed on contact with acidic substances. These colors are those observed in Example 1. The colour hue observed with the C naked eye is a slightly dull pale blue to green hue which become deeper with the lapse of time.

3 GB2196137A 3 Table 1

Melting Maximum 5 absorption point wavelength 0C nm 10 1 135-137 750 2 HO-@-NH-@-NH- 141-145 800 15 3 CH 3 0-@NH-@NH-@ 126.8-128.0 830 20 4 C 2 H 5 0-@-NH-@-NH-@ 148-157 830 HO 25 NH-@NH-@ 143.5-146.0 750 CH 3 0 30 6 NH-@NH--4@ 106.6-108 695 7 tert-C 4 H 9 CO. 0-@NH-@-NH-@ 102-106 720 35 8 NH 2 -@-NH-@-NH-@ 156.5-160 866 40 9 @NH-@-NH-@NH-@ 196.5-198.5 1005 45 CH 3 0 152.8-153.5 995 NH-@NH-@NH-@) 50 11 CH 3 770 55 HO-6NH-@-NH-@) 4 GB2196137A 4 Table 1 (Continued) Maximum Melting absorption 5 point wavelength Oc nm 10 CH 3 CH 3 12 HO-NH-@-NH-C 117.5-119.4 770 15 13 -NH-@-NH-(:217-219 880 QJ-9i H 20 14 [CH 3 N N e-CH 3 850 CH 3 0 25 b 1 _ t H N N CH 3 670 30 H H 16 tert-C 4 9 co. N eN c H 690 35 HO CH 3 CH 3 17 121.0-123.3 620 40 HO CH, CH 2-C 18 132-136 630 45 19 CH 3 -@-NH-@-NH-@) 145-148 782 50 2 0 @-NH-CH 3 71-73 723 H 3 55 21 - -Q-CH 3 123-126 640 9H 0 3 3 GB2196137A 5 Table 1 (Continued) Melting Maximum 5 absorption point wavelength Oc nm 118-120 870 10 22 (CH 3 2 N-(NH-NH-goCH3 2 3 196-198 880 15 24 CH 3 0-@-NH-@-NH-@NH-@ 1020 20 NH-(NH-(NH-(NH-C 247-249 935 25 26 (CH 3) 2 N-@NH-(-NH-C 129-130 880 27 CH 3 0 NH-,NH-NJ 122-124 990 30 CH 1025 35 28 CH 3 0-NH-@-NH-@-NH-@ 29 CH 3' @-NH-NH-.NH-C 187-188 905 40 6 GB2196137A 6 Some of the compounds represented by the formula (1) are disclosed in Japanese Patent LOP Publn. No. 98726/1979 or No. 38311/1980, and some of them are commercially available as antioxidants for rubber or the like. So far as we are aware of, however, it is not known that the compounds of the formula (1) have been used for the recording materials.

The color developing mechanism of the compounds represented by the formula (1) on contact 5 with acidic substances is not elucidated at present. However, in light of the fact that the developed colors become deeper with the lapse Qf time (during about 50 hours after intimate contact of the compounds with the acidic substances), or that the color development is acceler ated by the action of ultraviolet rays or the like, it is presumed that a certain oxidation reaction will take place in the presence of the acidic substances. 10 Acidic substances suitable for developing the compounds represented by the formula (1) inclu de, for example, inorganic acidic substances such as acid clay, activated clay, silica gel, zinc chloride, aluminum chloride and sulfamic acid; sulfonic acids such as benzenesulfonic acid, toluenesulfonic acid, naphthalenesulfonic acid and 2-hydroxy-4- methoxybenzophenone-5-sulfonic acid; carboxylic acids such as oxalic acid, tartaric acid, citric acid, palmitic acid, stearic acid, 15 methacrylic acid, maleic acid, fumaric acid, benzoic acid, toluic acid, phthalic acid, 2,6-dichloro benzoic acid, 4-nitrobenzoic acid, 4-cyanobenzoic acid, 4-tert- butylbenzoic acid, 4-hydroxybenzoic acid, salicyclic acid, 3-isopropylsalicyclic acid, 3-phenylsalicyclic acid, 3-cyclohexylsalicyclic acid, 3,5-di-tert-butylsalicyclic acid, 3-methyl-5-benzylsalicyclic acid, 3- phenyl-5-(a,a-dimethylbenzyl)saiicyclic acid, 3,5-di-(2-methylbenzyl)salicyclic acid, 3-cumylsalicyclic acid, gallic acid, 2-hydroxy-1- 20 benzyl-3-naphthonic acid, 2-acyloxy-l-naphthonic acid, 1-acyloxy-2- naphthonic acid and 3-acy loxy-2-naphthonic acid, and salts of these carboxylic acids with such metals as zinc, calcium, magnesium, aluminum and titanium; phthalic anhydride, benzoic anhydride, toluic anhydride, o sulfobenzoic anhydride, o-sulfophthalimide xanthic acid, water-insoluble polymers having in the molecule a carboxyl group or/and a sulfonyl group, or phenol resin developers such as p- 25 phenylphenol-formalin resins and p-butylphenol-acetylene resin, and mixtures of these phenol resin developers and the above-mentioned metal salts of carboxylic acids. However, the com pounds of the formula (1) will develop faintly with phenolic developers (e.g. bisphenol A or the like) which are commonly used in preparing heat-sensitive recording papers by the use of fluoran compounds or other conventional chromogenic dyes. 30 Table 2 shows that colors developed by the compounds of the formula (1) on contact with acidic substances become deeper with the lapse of time. In Table 2, there are shown reflectivity (%) of colors developed by compound No. 4 and compound No. 8 in Table 1 on various wavelengths (as measured over a spectrophotometer with an integrating sphere) after the lapse of 1 hour and 24 hours subsequent to color development operation in Example 1. In this 35 connection, reflection curves are shown in Figs. 1 and 2.

Table 2

40 Reflectivity (%) Wavelength Time Compound elapsed 700nm 800nm Xmin 900nm 45 (820nm) No. 4 1 hr. 33.5 20.5 20.0 24.0 24 hrs. 14.5 10.0 10.0 13.0 50 (866nm) No. 8 1 hr 56.5 26. 5 17.0 24.0 24 hrs. 13.5 8.8 7.0 8.0 55 Concrete forms of recording materials utilizing color development of the compounds of the formula (1) on contact with acidic substances include, for example, pressure-sensitive copying materials, heat-sensitive recording materials, heat-sensitive transfer recording materials, super sonic wave recording materials.for electrophotography using toners containing acidic substances 60 as developers, photosensitive recording materials, electron rays recording materials, discharge recording materials, stamping materials, stamp ink, typewriter ribbons, etc. Widely used sub strate for these recording materials include papers, synthetic papers, textile fabrics, nonwoven fabrics or high molecular materials such as synthetic resin films, synthetic resin plates, etc.

The compounds of the formula (1) also develop colors on contact with organohalogen com- 65 7 GB2196137A 7 pounds forming halogen radicals by the action of heat or/and light. Any organohalogen com pounds can be used in the present invention which include, for example, carbon tetrabromide, bromoform, bromochloroform, hexabromoethane, a-trichloromethylquinoline, tribromoacetic acid esters, hexabromodimethyl sulfone and 2,4,6-tris(trichloromethyl)triazine. The organohalogen compounds of the formulas (11) and (111) generate halogen radicals by the action of heat or/and 5 light and are particularly preferable as developers used in the present invention, xi 2 1_ 2 (R) Y-C X (11) P 10 13 x wherein R2 represents halogen, nitro, cyano or lower alkyl, p represents 0 or an integer of 1 to 5, R2 may be different substituents when p is 2 or more, Y represents 0 15 - S S - or C - 0 0 0 20 X1, X2 and X3 each represent hydrogen, chlorine or bromine, provided that all of X1, X2 and X3 are not hydrogen atoms at the same time.

0 25 11 1' 1-1 N - X 4 (111) I-, - C 11 0 30 wherein D represents -CH2-CH2-, (:::I / 3 (R 35 ) q or R 4 40 N 15 45 X R3 represents halogen, nitro or lower alkyl, q is 0 or an integer of 1 to 4, R3 may be different substituents when q is 2 or more, R4 and R5 may be the same or different and represent hydrogen or lower alkyl, and X4 and X5 may be the same or different and represent chlorine or 50 bromine.

The organohalogen compounds represented by the formula (11) or/and (111) are disclosed as developers for photosensitive recording materials in Japanese Patent Publication No. 1895/1972, Japanese Patent LOP Publn. Nos. 137126/1975, 212434/1982 and 132229/1983, and as developers for heat-sensitive recording materials in Japanese Patent LOP Pubin. No. 3791/1986. 55 Typical examples of the organohalogen compounds include, by way of illustration but not of limitation, for example, tribromomethylphenyl sulfone, trichloromethylphenyl sulfone, tribromome thyl-p-chlorophenyl sulfoge, trichloromethyl-p-chlorophenylsulfone, tribromomethyl-p-nitrophenyl sulfone, tribromomethyl-o-methylphenyl sulfone, tribromomethyl-o- methylphenyl sulfone, tribromo methyl-o-isopropylphenyl sulfone, a,ci,oL-tribromoacetophenone, a,a,otrichloroacetophenone, p-ni- 60 tro-a,a,a-tribromoacetophenone, p-chloro-a,a,a-tribromoacetophenone, tribromomethylphenyl sul foxide, trichloromethylphenyl sulfoxide, N-bromophthalimide, N-bromo-2chlorophthalimide, N bromo-1,2,3,4-tetrachlorophthalimide, 1,3-dichloro-5,5-dimethylhydantoin, 1,3-dibromo-5,5-dime thy[hydantoin, N-bromosuccinic imide and N-chlorosuccinic imide.

It is not elucidated at present by what mechanism the organohalogen compounds used in the 65 8 GB2196137A 8 present invention (hereinafter abbreviated as "the organohalogen compounds"), which generate halogen radicals by the action of heat or/and light, particularly the above-mentioned compounds of the formulas (11) and (111), exhibit color developing action. However, it is considered that the application of heat or irradiation with light of high energy (e.g. ultraviolet rays, hereinafter called "light") will generate a halogen radical, and parts of the formed halogen radicals react with 5 hydrogen donors (e.g. binders, water, etc.) to form acidic substances, whereby the compounds of the formula (1) develop colors by synergistic effect of the halogen radicals and acidic sub stances as formed. Accordingly, the proportions of the organohalogen compounds to the com pounds of the formula (1) cannot be decided indiscriminately, and should be decided taking into account the amount of halogen radicals formed by the application of heat or irradiation with light 10 as aforesaid.

The chromogenic recording materials of the present invention using the organohalogen com- pounds as developers exhibit excellent color forming characteristics as shown in Fig. 3. This Fig.

3 is reflection absorption curves of the color developed portions of heatsensitive recording papers prepared in Examples 6-9 using 0.05, 0.1, 0.5 and 1.0 part by weight of tribromome- 15 thylphenyl sulfone as a developer based on 1 part by weight of the compound of the formula &NH-NH-&NH0 20 as the compound of the general formula (1). The color development of these recording materials is of the characterstics that the developed color changes from grayish green to greenish black with increasing amount of the organohalogen compound.

Where heat-sensitive recording papers are prepared by using tribromomethylphenyl sulfone as the organohalogen compound, the proportion of the organohalogen compound is preferably 25 0.05-3 parts by weight per one part by weight of the compound of the formula (1).

Concrete forms of chromogenic recording materials utilizing color development of the com- pounds of the formula (1) on contact with the organohalogen compounds include, for example, heat-sensitive recording materials, photosensitive recording materials, heat-sensitive transfer re cording materials, electron rays recording materials and the like. Widely used substrates for 30 these recording materials include papers, synthetic papers, textile fabrics, nonwoven fabrics and high molecular materials such as synthetic resin films, synthetic resin plates, etc.

The compounds of the formula (1) also develop colors by the action of electron acceptable substances capable of forming charge transfer complexes. Of these electron acceptable sub stances are preferred those having 0.4 em. or more and especially preferably 0.7 e.v. or more 35 of an electron affinity. Such substances include, for example, 2,5dichloro-p-benzoquinone, tetra chloro-p-benzoquinone, tetracyano-p-benzoquinone, tetracyanoethylene, 1,1, 2,3,4,4-hexacyanobu tadiene, 2,3-dichloro- 1,4-naphthoqu i none, 9-dicyanomethylene-2,4,7trinitrofluorenone, or various quinodimethane derivatives, for example, 7,7,8,8-tetracyanoquinodimethane, 2,5-diethyl-7,7,8,8, tetracyanoquinodimethane, 11,11,12,12-tetracyano-1,4naphthoquinodimethane, 11,11,12,12-tetracyano-2,6-naphthoquinodimethane and tetracyanoanthraquinodimethane or anthrone derivatives.

The developed colors of the compounds of the formula (1) by the action of these substances as developers are of the characteristics that they very strongly absorb electromagnetic waves in near-infrared region.

The use and method of using the substances capable of forming charge transfer complexes 45 are substantially the same as in the case of the above-mentioned organohalogen compounds.

Of course, the compounds of the formula (1) can be used either singly or in combination.

Further, they may also be used in admixture with known conventional chromogenic dyes or/and chromogenic dyes as disclosed in the aforementioned literatures, which also exhibit their absorp tion in the near-infrared region. 50 The known conventional chromogenic dyes include, by way of illustration but not of limitation, for example, blue chromogenic dyes such as crystal violet lactone, benzoyl leucomethylene blue and 5(or 7)-(l-octyl-2-methylindol-3-yl)-5(or 7)-(4-diethylamino-2ethoxyphenyl)-5,7-dihydro- furo(3,4-b)-pyridine-7(or 5)-one; green chromogenic dyes such as 3- diethylamino-5-methyl-7-di benzylaminofluoran qpd 3-N-isobutylethylamino-7-phenylaminofluoran; red chromogenic dyes such 55 as 3-diethylamino-6-methyl-7-chlorofluoran and 3-cyclohexylamino-6chlorofluoran; and black chromogenic dyes such as 3-diethylamino-6-methyl-7-phenylaminofluoran, 3- N-methyl-cyclohexy lam ino-6-methyl-7-phenyla minof luora n, 3-N-methyl-n-propylamino-6methyl-7-phenylaminofluoran, 3-N-isopentyl-ethylamino-6-methyl-7-phenylaminofluoran, 3-diethylamino-7m-trifluoromethylpheny- laminofluoran and 3-di-n-butylamino-7-chlorophenylaminofluoran. 60 The method of using the compounds of the formula (1) for pressure- sensitive copying papers is similar to that Of conventional fluoran compounds. The pressure-sensitive copying papers using the compounds of the formula (1) can be prepared in accordance with procedures disclosed in US Patents 2,548,365, 2,548,366, 2,800,457 and 2,800,458, Japanese Patent LOP Publns.

Nos. 112041/1983 or 139738/1983. When the compounds of the formula (1) are used in 65 9 GB2196137A 9 conventional pressure-sensitive copying papers, acidic substances are used as developers. How ever, developers other than the acidic substances can also be used where both heat and light are applied at the time of recording.

The compounds of the formula (1) can be used in the preparation of heatsensitive recording papers in accordance with the manner described in, e.g., Japanese Patent Publications Nos. 5 27579/1964, 4160/1968 and 14039/1970, Japanese Patent LOP Pubins. Nos. 7087/1984 and 106992/1984. In this case, however, the compounds of the formula (1) and developers therefor are not always required to be present in the same coated layer and they may be incorporated separately in the upper and lower layers of a double layer.

When acidic substances are used as developers, they are preferably those which are stronger 10 in acidity than the developers used in conventional heat-sensitive recording papers. Accordingly, where heat-sensitive recording papers are prepared by the use of the compounds of the formula (1) in combination with conventional chromogenic dyes or/and chromogenic dyes having their absorption in the near-infrared region, it is desirable that these chromogenic dyes do not contact directly with these developers prior to color development operation. This may be accomplished 15 by several methods, for example, a method in which the chromogenic dyes are used by encapsulation in a microcapsule, or a method in which the chromogenic dyes and developers are not mixed together and are coated onto a support as a separate layer (in that case a suitable insulation layer may also be provided between two layers).

Color development of the compounds of the formula (1) on contact with acidic substances is 20 faint as mentioned previously when said acidic substances are those conventionally used in the preparation of heat-sensitive recording papers, such as bisphenol A. Even in this case, however, the colors developed become deeper with the lapse of time or under exposure to sunlight.

Accordingly, the compounds of the formula (1) function as image stabilizers and permit the preparation of heat-sensitive recording papers which are very fast to the lapse of time and light 25 radiation, if heat-sensitive recording papers are prepared according to the usual way by using the compounds of the formula (1) in combination with conventional chromogenic dyes or/and chro mogenic dyes having their absorption in the near-infrared region on color development and also using as developers acidic substances usually used in the preparation of heat-sensitive recording papers, for example, bisphenol A, benzyl p-hydroxybenzoate, 4-hydroxy-4'- isopropoxydiphenyI 30 sulfone, 4-hydroxy-4'-n-butoxy-di-phenyl sulfone and bis(phydroxyphenylthioethoxy)-methylene and the like. The colors developed from the compounds of the formula (1) become gradually deeper a ' nd have also their absorption in the near-infrared region, and hence these compounds are very effective as image stabilizers for the chromogenic dyes having their absorption in the near-infrared region as disclosed in the aforementioned literatures. Of course, such image stabiliz- 35 ing effect of the compounds of the formula (1) can be utilized also in pressure-sensitive copying papers.

In heat-sensitive recording papers prepared by the combination of the compounds of the formula (1) and the organohalogen compounds, said organohalogen compounds exhibit color development effect by not only application of heat but also by light irradiation and hence they 40 have a possibility of staining background of the recording papers (spontaneous coloration in unheated portions of said recording papers). However, in the case of heat- sensitive recording papers prepared by conventional methods, the organohalogen compounds are incorporated in the heat-sensitive recording layer in the form of particles, and moreover, said layer contains anti sticking agents and other additives, and hence the amount of light radiation to the organohalo- 45 gen compounds is inevitably small, whereby the stain of background in the recording papers becomes practically negligible. The means for preventing the stain of background include, for example, a process in which the chromogenic substances and organohalogen compounds are coated, without mixing thereof, onto a support as separate layers (in that case, a suitable insulation layer may also be provided between the two layers), a process in which either or both 50 of the chromogenic substances and organohalogen compounds are encapsulated into heat fusible microcapsules, a process in which ultraviolet absorbers are incorporated into the heat-sensitive recording layer, a process in which the heat-sensitive recording layer is overcoated with ultravio let absorbing substances or a process in which a light-barrier layer is provided on the surface of heat-sensitive recording layer. 55 The process for the incorporation of the ultraviolet absorbers into the heat-sensitive recording paper or the process for overcoating the heat-sensitive recording layer surface with the ultravio let absorbers include those as disclosed, for example, in Japanese Patent LOP Publns. Nos.

146412/1975, 17346/1978, 107388/1985 and 112487/1985.

In the preparation of heat-sensitive recording papers by using the compounds of the formula (1) 60 and the organohalogen compounds or/and the electron acceptable substances capable of forming charge transfer complexes, the aforementioned various acidic substances or acidic substances used as developers in preparing conventional heat-sensitive recording materials, e.g., bisphenol A, benzyl p-hydroxybenzoate, 4-hydroxy-4'-isopropoxydiphenyl sulfone, 4- hydroxy-4'-n-butoxydi phenyl sulfone and bis(p-hydroxyphenylthioethoxy)-methylene may be used in combination with 65 GB2196137A 10 the compounds of the formula (1) when used alone or even when used in combination with conventional chromogenic dyes.

The compounds of the formula (1) according to the present invention may be used for photosensitive record in accordance with the procedures disclosed in Japanese Patent Pubins.

Nos. 24188/1963, 10550/1970 and 45978/1974, Japanese Patent LOP Pubins. Nos. 5 80120/1975, 126228/1975, 141633/1977 and 147829/1979. Fig. 4 shows that the chromo genic recording materials as prepared in Example 14 develop colors by ultraviolet light radiation.

Furthermore, the compounds of the formula (1) can be used for heatsensitive transfer in accordance with the procedures disclosed in Japanese Patent LOP Pubins. Nos. 212985/1983, 33185/1984, 42995/1984 and 225986/1984, or can be used for photosensitive printing ma- 10 terials in accordance with the procedure disclosed in Japanese Patent LOP Publn. No.

- 12104/1973.

The recording papers prepared by the above processes may be provided, if necessary, on the surface with a protective layer and may be provided also on the back with a sticky layer for the convenience of using them as labels. 15 The recording materials prepared in accordance with the aboveprocesses are used in a wide variety of fields which include reproduction of books and documents and the like, electronic computers, facsimiles, bar cords, ticket vending machines and labels, and moreover systems for preventing forgery and reproduction that cannot be seen with the naked eye, or unlocking apparatus or high density information such as laser disks, etc. 20 The following examples shall further illustrate the invention.

EXAMPLE 1

In a solution of 0.1 g of a phenylenedia mine derivative (compound Nos. 125) shown in Table 1 in 20 ml of toluene was immersed for 15 seconds a clay coated bottom sheet for use in 25 pressure-sensitive copying papers manufactured by Fuji Photo Film Co., Ltd., and the bottom sheet was then suspended vertically for 10 seconds to drop the solution therefrom. Thereafter, the bottom sheet was wiped up on both sides with a filter paper and left to vaporize the solvent. Then, the bottom sheet developed a slightly dull, pale blue color or pale greenish blue color. A reflection curve of the developed surface of each bottom sheet was measured with a 30 spectrophotometer-integrating sphere to obtain a maximum absorption wavelength. The results are shown in Table 1.

EXAMPLE 2

A mixture of 4.0 g of a phenylenediamine derivative, compound No. 6 in Table 1, 50.0 g of 35 alkyldiphenyl methane (Highsole SAS 296, a product of Nisseki Kagaku K.K. ) and 36.0 g of diisopropyl naphthalene (KMC-1 13, a product of Kureha Kagaku K.K.) was heated and dissolved to prepare a solution. The solution was stirred at 90'C. for 10 minutes and then allowed to cool (Solution A).

On one hand, in a mixture comprising 30.0 g of a 10% aqueous solution of sulfonic acid- 40 modified polyviny alcohol (Gosenol CKS-50, an average polymerization degree: about 300, de gree of saponification: 97%, degree of modification: 10 mol%, a product of the Nihon Gosei Kagaku Kogyo K.K.)15.0 g of a 10% aqueous solution of an ethylenernaleic anhydride co polymer (EMA-31, a product of Monsanto) and 67.5 ml of water were dissolved 5.0 g of urea and 0.5 g of resorcinol, and the solution was adjusted to pH 3.4 with a 20% aqueous caustic 45 soda solution (Solution B).

Solution A was added to Solution B, and was stirred with a homomixer at 9000 rpm for 2 minutes to prepare an emulsion. Then, 14.0 g of a 35% aqueous formalin solution was added to the solution, stirred at 9000 rpm for 3 minutes with the subsequent decrease to 8000 rpm and raised to 60-65'C, and continued to stir at that temperature for additional 60 minutes. The 50 stirring with a homomixer was then ceased, the solution was cooled to 40C. , and was adjusted to pH 7.5 with'a 28% aqueous ammonia solution to prepare a suspension of microcapsules.

A mixture comprising 27.0 g of the suspension (kept at a temperature of below 300C), 3.5 g of wheat starch, 8.5 g of a 8% wheat starch solution and 34.0 ml of water was stirred with a stirrer at room temperature for 30 minutes to prepare a coating solution. 55 This coating solution was coated onto a white paper with Wire Bar No. 12, and dried for 3 minutes with a hot air at 60'C. to prepare a topsheet for pressure- sensitive copying paper.

This topsheet was superposed on a bottom sheet for pressure-sensitive copying paper and a pressure was applied to develop a color on the clay coated surface of the bottom sheet. The developed color was a slightly dull, pale blue. 60 EXAMPLE 3

Into a 250 ml polyethylene bottle was charged a mixture comprising 14.0 g of a phenylenedi- amine derivative, compound No. 1 in Table 1, 41.5 g of a 15% aqueous solution of polyvinyl alcohol (Kuraray-105, a product of Kuraray Co., Ltd.), 4.5 g of clay (UW- 90, a product of 65 11 GB2196137A 11 Engelhaldt Co., Ltd.) and 40.0 g of pure water, together with 150 g of glass beads (1-1.5 mm in diameter), the bottle was sealed, attached to a paint conditioner manufactured by Red Devil Col., Ltd. and shaken at a vibration rate of 630 times/min. for 5 hours. Thereafter, the glass beads were removed to prepare an aqueous suspension of the above- mentioned phenylenediam ine derivative. 5 This aqueous suspension was coated with Wire Bar No. 18 onto the clay coated surface of a bottom sheet for pressure-sensitive copying paper and dried to prepare a heat-sensitive record ing paper. This heat-sensitive recording paper was heated at 150'C. for 5 seconds with a dry heat tester (manufactured by Kishino Kagaku Kikai Seisakusho K.K.), whereupon a slightly dull, pale greenish blue color was developed on the heated portion of the heat- sensitive recording 10 paper. After one hour, a reflection spectrum of this color-developed portion was measured to 1 give 20.2% of reflectivity at a wavelength of 800 nm.

EXAMPLE 4

A coating solution containing a suspension of microcapsules having encapsulized the chromo- 15 genic dye was prepared by using substantially the same procedure as described in Example 2, but substituting 4.0 g of 3-N-methylcyclohexylamino-6-methyl-7- phenylaminofluoran, a black chro mogenic dye, for 4.0 9 of the phenylenediamine derivative, compound No. 6 in Table 1 used therein.

This coating solution was coated with Wire Bar No. 12 onto the clay coated surface of a 20 bottom sheet for pressure-sensitive copying paper and dried. Onto the dried surface was further coated the aqueous suspension prepared in Example 3 with Wire Bar No. 18 and then dried.

This coated paper was heated with the dry heat tester in the same manner as in Example 3, whereupon a black color was developed on the heated portion. The reflection state of the near infrared region was substantially the same as in Example 3. 25 EXAMPLE 5

A heat-sensitive recording paper was prepared and color developed by heating in accordance with substantially the same procedure as described in Example 3, but substituting a mixture of 10.0 g of a phenylenediamine derivative, compound No. 9 in Table 1 and 4. 0 9 of 3-pphenylaminophenylamino-6-methyi-7-chlorofluoran for 14.0 g of the phenylenediamine derivative used in Example 3. The developed color had greenish black hue. After twenty four hours, a reflection spectrum of the color developed portion was measured, whereupon the reflectivity was 8% at 600 nm., 8% at 700 nm., 5% at 800 nm. and 6% at 900 nm.

35 EXAMPLE 6

Suspension A-1 7.0 g 40 H H H Clay 11. 5 g 45 15% aq. polyvinyl alcohol solution 41.5 g Water 40.0 g 50 Suspension B-1 Tribromomethylpheny sulfone 3.5 g 55 Clay 15. 0 g 15% aq. polyvinyl alcohol solution 41.5 g 60 Water 40.0 g The above ingredients were individually charged, together with 150 g of glass beads (1-1.5 65 12 GB2196137A 12 mm in diameter), into separate polyethylene bottles, the bottles were sealed, and milled for several hours with a paint conditioner manufactured by Red Devil Co., Ltd. to prepare a Suspen sion A-1 and Suspension B-1, respectively. The former suspension was mixed with the latter suspension in the proportion of 1 to 2 to prepare a coating solution.

This coating solution was coated onto a white paper and then dried to prepare a heat- 5 sensitive recording paper 1.

This heat-sensitive recording paper I was heated on both sides at 200'C. with a dry heat tester (manufactured by Kishino Kagaku Kikai K.K.) to develop a color. The developed color was greenish black. Using a spectrophotometer with an integrating sphere (U- 3400 manufactured by Hitachi Co., Ltd.), the color developed portion of the heat-sensitive recording paper I was 10 measured for reflection curve at a wavelength of 400-1300 nm and for reflectivity at 700, 800, 900 and 1000 nm, respectively, and the color undeveloped portion was measured for reflectiv ity.

The reflection curve is shown in Fig. 3 and the reflectivity is shown in Table 3.

15 N' EXAMPLES 7-9

Following substantially the same procedure as described in Example 6 but changing the amount of tribromomethylphenyl sulfone used therein, there were prepared Suspensions B-2, B-3 and B-4 having their respective compositions as mentioned below.

20 Suspension B-2 Tribromomethylphenyl sulfone 1.75 g Clay 16.75 g 15% aq. polyvinyl alcohol 25 solution 41.5 g Water 40.0 g Suspension B-3 Tribromomethylphenyl 30 sulfone 0.35 g Clay 18.15 g 15% aq. polyvinyl alcohol solution 41.5 g Water 40.0 g 35 Suspension B-4 Tribromomethylphenyl sulfone 0. 18 g Clay 18.32 g 40 15% aq. polyvinyl alcohol solution 41.5 g Water 40.0 g Instead of Suspension B-1 used in Example 6, the above-mentioned Suspensions B-2, B-3 and 45 B-4 were individually mixed with Suspsneion A-1 to prepare corresponding coating solutions, and heat-sensitive recording papers 11, 111 and IV were prepared by using these coating solutions, respectively. In the same manner as in Example 6, these heat-sensitive recording papers were allowed to develop colors, and reflection curves of the color developed portions were measured.

The reflection curves were shown in Fig. 3. The developed colors in the heat-sensitive recording 50 papers 11, 111 and IV were blackish green, green and yellowish green, respectively.

EXAMPLES 10-12 Following substantially the same procedure as used in the preparation of Suspension A-1 of Example 6, there were prepared Suspensions Ar, A-3 and A-4 having their respective compo- 55 sitions as mentioned below.

13 GB2196137A 13 Suspension A-2 7.0 g H H 5 Clay 11.5 g 15% aq. polyvinyl alcohol solution 41.5 g 10 Water 40.0 g Suspension A-3 15 7.0 g 110101 H H Clay 11.5 g 20 15% aq. polyvinyl alcohol solution 41.5 g Water 40.0 g 25 Suspension A-4 Q-N-N-OCH 3 7.0 1 1 30 H H Clay 11.5 g 15% aq. polyvinyl alcohol 35 solution 41.5 g Water 40.0 g 40 Instead of Supension A-1 used in Example 6, the above-mentioned suspensions were individu- ally mixed with Suspension B-1 to prepare corresponding coating solutions, and heat-sensitive recording papers V, VI and VII were prepared by using these coating solutions. In the same manner as in Example 6, these heat-sensitive recording papers were allowed to develop colors, 45 and the reflectivities of the color developed and undeveloped portions were measured at 700, 800, 900 and 1000 nm. The measured values are shown in Table 3. The developed colors of the heat-sensitive recording papers V, VI and V11 were bluish black, reddish black, and greenish black, respectively.

14 GB2196137A 14 Table 3

Reflectivity % 700 nm 800 nm 900 nm 1000 nm Heat-sensitive recording paper I Colored portion 10.5 8.8 6.2 5.3 Uncolored portion 96.2 96.2 97.5 97.5 10 Heat-sensitive recording paper V Colored portion 11.9 14.1 13.7 19.2 15 Uncolored portion 96.7 98.2 99.1 99.2 Heat-sensitive recording paper VI Colored portion 13.3 13.1 11.2 17.1 20 Uncolored portion 96.9 97.5 97.7 97.9 Heat-sensitive- 25recording paper VII 25 Colored portion 28.6 33.7 34.9 32.6 Uncolored portion 96.2 97.9 98.8 990 EXAMPLE 13 30

Following substantially the same procedure as described in Example 6, but substituting 1,3- dibromo-5,5-dimethylhydantoin for tribromomethylphenyl sulfone in Suspension B-1 of Example 6, a heat-sensitive recording paper VIII was prepared and heated to develop a blackish brown color. The developed color absorbed electromagnetic waves in the near- infrared region.

35 EXAMPLE 14

Cellulose acetate butyrate 5g Ethyl acetate 5 g 40 N_ &0 N- N 0.16 g I 1 00 - I -@) H H H k 45 Tribromomethylphenyl sulfone 0.03 g A coating solution having the above-mentioned composition was prepared while shielding the light. The coating solution was coated onto a white paper and then dried to prepare a photosen- 50 sitive recording paper. This recording paper was irradiated with ultraviolet rays to develop a yellowish green color. In the same manner as in Example 6, a reflection curve of the color developed portion was measured. The results are shown in Fig. 4.

EXAMPLE 15 55

A solution of 0.06 g of a phenylenediamine derivative, compound No. 3 in Table 1, 0.066 g of tetrabromomethane and 0.2 g of cellulose acetate butyrate in 1.5 g of acetone was coated on a transparent polyethylene film and then dried.

Separately, the same solution as above but containing the compound No. 12 in Table 1 instead of the compound No. 3 in Table 1 was coated onto a transparent polyethylene film and 60 then dried.

These polyethylene films were irradiated with light from a 400 W high pressure mercury lamp for 1 minute at a distance of 20 cm, whereupon a slightly dull, pale blue color was developed on both films. Reflectivities (%) as measured at various wavelengths of the color developed portion of the films were shown in Table 4. 65 GB2196137A 15 Table 4

700 nm 800 nm 900 nm Compound No. 3 5 4 5 5 Compound No. 12 6 5 6 10 EXAM PLE 16 Suspension A-5 C11 3 0 NH 15 -(D-NHNH-Q 7.0 g Clay 11.5 g 15 % aq. polyvinyl alcohol 20 solution 41.5 g Water 40.0 g 25 Suspension B-5 Tetrachlorobenzoquinone 10.5 g Clay 8.0 g 30 15% aq. polyvinyl alcohol solution 41.5 g Water 40.0 g 35 Suspension B-6 Tetracyanoquinodimethane 10.5 q Clay 8.0 g 40 15% aq. polyvinyl alcohol solution 41.5 g 45 Water 40.0 g Following substantially the same procedure as described in Example 6, Suspension A-5, 50 Suspension B-5 and Suspension B-6 were respectively prepared from the above compositions.

Suspension A-5 was mixed with Suspension B-5 in the proportion of 1 to 2 to prepare a coating solution. The coating solution was then coated onto a white paper and dried to prepare a heat-sensitive recording paper IX.

The above procedure was repeated but substituting Suspension B-6 for Suspension B-5 to 55 prepare a heat-sensitive recording paper X.

These heat-sensitive recording papers were heated to develop their respective colors under the same conditions as in Example 6. Both developed colors were dark green. Reflection curves of the developed colors were shown in Fig. 5.

The coated surface of these recording papers had a pale, dark yellow color for the recording 60 paper IX and a dark yellow color for the recording paper X.

16 GB2196137A 16 EXAMPLE 17

Suspension A-6 OCH 5 (CH 3)2 N-@NH-@-NH7.0 g Clay 11.5 g 10 15% aq. polyvinyl alcohol solution 41.5 g Water 40.0 g 15 Following substantially the same procedure as described in Example 16, there was prepared Suspension A-6 having the composition mentioned above.

In the same manner as described in Example 16, except that instead of Suspension A-5, 20 Suspension A-6 was mixed with Suspension B-5 or Suspension B-6, a heat- sensitive recording paper XI and a heat-sensitive recording paper X11 were prepared and heated to develop colors.

The developed colors had a slightly reddish black hue for the recording paper XI, and a black hue for the recording paper XII. Reflection curves of these developed colors are shown in Fig. 5.

The coated surface (before heating) of these recording papers had a green color for the 25 recording paper X1, and a dark green color for the recording paper XII.

EXAMPLE 18

Suspension B-7 Zinc p-nitrobenzoate 10.5 g 30 Clay 8.0 g 15% aq. polyvinyl alcohol 41.5 g solution Water 40.0 g 35 Suspension B-7 of the above composition was prepared in the same manner as in Example 6.

Suspension A-5 as prepared in Example 16 was mixed with Suspension B-7 in the proportion of 1 to 2 to prepare a coating solution. The coating solution was coated onto a white paper and dried to prepare a heat-sensitive recording paper. The heat-sensitive recording paper was heated to develop under the same conditions as in Example 6. The developed color was a pale 40 purple. The refleGtivities of the developed color over different wavelengths are shown in Table 5.

Table 5

45 Wavelength (nm) 700 800 900 1000 1100 Reflectivity (%) 53.5 45.5 34.5 19.2 15.1 50 EXAMPLE 19

Following substantially the same procedure as described in Example 18, but substituting Zinc p-cyanobenzoate for zinc p-nitrobenzoate used i J n Example 18, a heat- sensitive recording paper was prepared and heated to develop. The devel6ped color absorbed electromagnetic waves in 55 the near-infrared region in a similar manner to that of Example 18.

Claims

1. A recording material which comprises a developer and a phenylenediamine or naphthylene- diamine derivative represented by the formula 1 60 17 GB2196137A 17 N R1 N - (D 1 5 R' wherein A, B and C are independently a benzene or naphthalene ring, each of which may have at least one substituent which is halogen, cyano, hydroxyl, alkyl, aryl, alkoxy, aryloxy, arylalkoxy, 10 alkylcarbonyloxy, arylcarbonyloxy, amino, alkyl-substituted amino, pyrrolidino, piperidino, bryl substituted amino, or carbamoyl which may be substituted with alkyl or aryl, and and R and R', which may be the same or different, are each hydrogen, lower alky], aryl or aralkyl.

2. A recording material according to claim 1 in which at least one of A, B and C is a substituted ring. 15

3. A recording material according to claim 2 in which a substituent is alky], alkylcarbonyloxy, alkyl-substituted amino or alkyl-substituted carbamoyl in which the alkyl moiety contains 1 to 8 carbon atoms.

4. A recording material according to claim 2 or 3 in which a substituent is alkoxy or arylalkoxy in which the alkoxy moiety contains 1 to

5 carbon atoms. 20 5. A recording material according to claim 2, 3 or 4 in which a substituent is aryl, aryloxy, arylcarbonyloxy, aryl-substituted amino or aryl-substituted carbamoyl in which the aryl group is phenyl or naphthyl which may be substituted by at least one C1-5 alkyl, C1-5 alkoxy, or amino which may be substituted by at least one C,-, alkyl.

6. A recording material according to any one of the preceding claims in which R and R', 25 which may be the same or different, are each hydrogen, C,,, alkyl or phenyl, naphthyl or phenyl C,-, alkyl which may be substituted by at least one C,-, alkyl, C1-5 alkoxy, halogen, hydroxyl or amino which may be substituted by at least one C1-5 alkyl.

7. A recording materal in which the compound of formula 1 is one of compounds Nos. 1 to 29 defined herein. 30

8. A recording material according to any one of the preceding claims wherein the developer is an acidic substance.

9. A recording material according to any one of claims 1 to 7 wherein the developer is an organohalogen compound which is capable of forming a halogen radical by the action of heat and/or light. 35

10. A recording material according to claim 9 in which the organo-halogen is of formula 11 xl 2 M 1 _C_X2 (R) p 13 40 X il in which p is an integer from 0 to 5, R2, each of which may be different when p is greater than 1 1, is halogen, nitro, cyano or C,-, alkyl, 0 45 Y is - S S - or - C 1 11 11 50 U U 0 Xl, X2 and X3, which may be the same or different, are each hydrogen, chlorine or bromine, provided that at least one of Xl, X2 and X3 is chlorine or bromine.

11. A recording material according to claim 9 in which the organohalogen is of formula Ill 55 0 N X Ill 60 C 1 in which D is -CH2-CH2-, 65 18 GB2196137A 18 3 " (R )CT 5 or R 4 1 10 C - N 5 R X in which q is an integer from 0 to 4, R3 15 each of which may be different when q is greater than 1, is halogen, nitro or Cj-, alkyl, R4 and R5, which may be the same or different, are each hydrogen or Cj-, alkyl and X4 and X5, which may be the same or different, are each chlorine or bromine.

12. A recording material according to any one of claims 1 to 7 wherein the developer is an electron accepting substance capable of forming a charge transfer complex. 20

13. A recording material according to claim 12 in which the developer has an electron affinity of at least 0.4 eV.

14. A recording material according to claim 1 substantially as hereinbefore described.

Published 1988 at The Patent Office, State House, 66/71 High Holborn, London WC 1 R 4TP. Further copies may be obtained from The Patent Office, Sales Branch, St Mary Cray, Orpington, Kent BR5 3RD. Printed by Burgess & Son (Abingdon) Ltd. Con. 1/87.