United States Patent (19) (11) 3,947,471 Akamatsu Et Al

United States Patent (19) (11) 3,947,471 Akamatsu et al. (45) Mar. 30, 1976

54 BENZ (c) FLUORAN COMPOUNDS AND 56 References Cited RECORDING SHEET CONTAINING THEM UNITED STATES PATENTS Inventors: Takashi Akamatsu, Ashiya; Koichi 1,194,380 8/1916 Hagenbach...... 260/335 Koga, Toyonaka; Mitsuru Kondo, 3,654,314 4/1972 Farber et al...... 260/335 Kawanishi; Makoto Miyake, 3,669,711 6/1972 Kimura et al...... 260/335 Nishinomiya; Hiroshi Twasaki, 3,691,203 9/1972 Koga et al...... 260/335 Takatsuki; Masatoshi Matsuo, 3,849,164 l l 11974 Schwab et al...... 260/335 Ibaragi; Seiji Hotta, Hirakata; Isao FOREIGN PATENTS OR APPLICATIONS Yuji, Takarazuka, Yukiaki to, 2,024,859 1/1970 Germany Minoo, all of Japan 73 Assignees: Sumitomo Chemical Company, Ltd., Primary Examiner-Norma S. Milestone Osaka; Kanzaki Paper Attorney, Agent, or Firm-Stevens, Davis, Miller & Manufacturing Co., Ltd., Tokyo, Mosher both of Japan (57) ABSTRACT 22 Filed: May 20, 1974 Novel benzcifluoran compounds such as 2 phenylamino-8-diethylamino-benzcifluoran, 2 21) Appl. No.: 471,698 (2',4',6'-trimethylphenylamino)-8-diethylamino Related U.S. Application Data benzcifluoran and N-8-diethylaminobenzcifluoran 63 Continuation of Ser. No. 188,541, Oct. 12, 1971, 2-yl)-N-6-diethylaminofluoran-2-yl)amine, which are abandoned. useful as a coloring material for record material sys tems such as pressure-sensitive copying paper or heat 30 Foreign Application Priority Data sensitive copying paper, wherein colored images Dec. 26, 1970 Japan...... 46-130387 formed by an electron-donoracceptor color-forming Dec. 26, 1970 Japan...... 46-30392 reaction between coloring material and acidic material. 52) U.S. Cl...... 260/.335; 282/27.5 51 int. C.’...... C07D 311/84 58 Field of Search...... 260/335 9 Claims, No Drawings 3,947,471 2 (wherein R5 stands for hydrogen atom, a lower alkyl, a BENZ (C) FLUORAN COMPOUNDS AND lower acyl, a lower haloalkyl, a lower alkoxy, nitro, a RECORDING SHEET CONTAINING THEM halogen, a lower alkoxycarbonyl, a lower alkanesulfo nyl, benzenesulfonyl, toluenesulfonyl, a haloben This is a continuation of application Ser. No. 188,544 5 zenesulfonyl or methoxybenzenesulfonyl;Rs represents filed Oct. 12, 1971, and now abandoned. hydrogen, a lower alkyl, a lower alkoxy, a halogen, This invention relates to a chromogenic compounds nitro, amino, or an amino group substituted by at least for use in recording sheet which develops color images one lower alkyl group; n is an integer of 1 to 7; R, by an electro donor-acceptor color-forming reaction stands for hydrogen, a lower alkyl, a lower haloalkyl, between chromogenic material and acidic material 10 phenyl, a halophenyl, tolyl, methoxyphenyl or nitro which react upon contact to produce a color. phenyl; Rs represents hydrogen, a lower alkyl, a lower More particularly, the present invention relates to alkenyl, a lower alkynyl, a lower haloalkyl or a lower novel benzcifluorans represented by the following alkoxyalkyl; Rs represents hydrogen, a lower alkyl, a general formulas (I), which have never been disclosed lower alkoxy, a halogen or nitro; Rio stands for hydro in prior art references, methods for the preparation 15 gen, a lower alkyl, benzyl or phenyl; Y signifies hydro thereof and recording sheet containing the same as gen, a lower alkyl, a lower alkoxy, a halogen, nitro, chromogenic materials. amino or an amino substituted by at least one lower alkyl group; Z is hydrogen, a lower alkyl, a halogen, a 20 lower alkoxy, nitro, amino, an amino substituted by at least one lower alkyl group or a group of (I) - N = CH -- B wherein B represents hydrogen, a lower alkyl, phenyl unsubstituted or substituted by a lower alkyl, a lower 25 alkoxy, a halogen or nitro; m is an integer of 1 to 4; and R signifies a group of

wherein R and Reach signify hydrogen, a lower alkyl, a lower alkoxyalkyl, a lower haloalkyl, benzyl, or a 30 benzyl substituted by a lower alkoxy, a lower alkyl, a halogen or nitro; Ra signifyies hydrogen, a lower alkyl, a lower alkoxyalkyl, a lower hydroxyalkyl, a lower haloalkyl, a lower cyanoalkyl, carbamoyl, a lower alke nyl, a lower alkynyl or a group of 35 -la-Gas -"2"-G- G-(Rs) 40 o -Ge (t). -SC-(Rs) -CH - CH = CH2- R7 , wherein R, R and m are as defined above, and Y, signifies hydrogen, a lower alkyl, a lower alkoxy, a (CH2CE CH3 R7 -COR8 , SO2Re halogen, nitro, amino or an amino substituted by at 50 least one lower alkyl group, and A signifies benzene or naphthalene nucleus. . . " " . . . . . , ', Throughout the present specification, the term -CO-Q g “lower" as is seen in "lower alkyl group' indicates that the number of carbon atoms is 1 to 4...... 55 In the present specification, the present benz(c)-fluo rans are named and the position substituted in the benzcifluoran nucleus are numbered as follows:

or -CH2COORO 3,947,471 3 4. 2-(N-methyl-3'-methyl-5'-chloro-anilino)-8-dime 1. These fluoran compounds represented by the gen thylamino-benzc) fluoran eral formula (I) are colorless and stable in air at ordi So far oil carbon paper was used for making out nary temperature, but, the compounds (I) change in documents and slips as office work materials. It has color from white to red, blue, green or black when they drawbacks that it is liable to stain clothes and hands are brought into contact with an acidic electron-accep and it is troublesome to insert the oil carbon paper tor explained in detail above. between documents and slips. W 2. These fluoran compounds (I) show all sorts of dark In order to eliminate the inefficiencies and defects of colors, for example, deep red, dark green, dark blue the oil carbon paper, pressure-sensitive copying paper green, dark greenish black, or black according to the or noncarbon paper, which is economic and handy, has O number, kind and position of substituents. recently made its debut in place of the oil carbon paper These various colors are due to the same benz complying with demand for speed-up of office works. cifluoran nucleus except the kind, number and posi Heretofore, leucoauramines, leucomethyleneblues, tion of substituents. The present benzc fluoran com phthalides and fluorans are well known as color precur pounds have almost the same color developing speed sors. They are colorless or nearly colorless compounds, 15 and the pressure-sensitive copying paper obtained by which may change to a certain coloring matter when mixing the present benzcifluoran compounds shows they are brought into contact with acidic electron no lag of the color developing time and changes the acceptor as explained below. . color of the image. For example, 2-methyl-6-diethylamino-fluoran hav It is also possible to use the said compounds together ing the following formula (II) is one of the well-known with other color precursors such as C.V.L. (crystal color precursors which are colorless compounds under violet lactone), B.L.M.B. (benzoyl leucomethylene ordinary condition but change to red coloring matters . . blue) or 2-methyl-6-diethylaminofluoran, etc. to obtain by opening their lactone ring when they are brought a special color such as blue-black or black image on the into contact with acidic electron-acceptor. paper without spoiling the other color precursers. 25 These are significant features of the present invention. 3. These benzcifluoran compounds are well soluble under colorless condition in a non-volatile non-polar (II) solvent used for preparing a recording sheet. Examples 30 of the non-polar solvent are as follows: - - - Chlorinated benzenes such as trichlorobenzenes and tetrachlorobenzenes; chlorinated biphenyls such as The pressure-sensitive copying paper is usually pre dichlorodiphenyls, trichlorodiphenyls, and tetra pared by coating a back side of one sheet of paper with chlorodiphenyls; alkylated benzenes; alkylated naph a color precursor such as a leucoauramine or a fluoran, 35 thalenes such as dimethylnaphthalene and dipropyl and coating a surface of another sheet of paper with an naphthalene; mineral oil; paraffin oil; olive oil; and acidic electron-acceptor such as kaolin, bentonite, tricresyl phosphate, etc. activated clay, acid clay, aluminum silicate, attapulgite, Such good solubility in the above solvents is probably metal oxides, metal chlorides, metal sulfates, organic caused by the naphthalene ring in the benz-clfluoran acids such as phenols, aliphatic acids or tannic acid, or 40 nucleus represented by the general formula (I). Good phenolic resins such as p-phenylphenol-formaldehyde solubility particularly in the aromatic solvents makes it resin, p-cyclohexylphenol-formaldehyde resin, etc. The easy to prepare the recording sheet and to obtain a pressure-sensitive copying paper is used by placing the deep image on the paper. coated papers upon one another so that the back side 4. The present fluoran compounds have no solubility of the first paper may be faced to the surface of the 45 and good stability in water, acids or alkalis. For exam second paper, and the back side of the second paper to ple, 2-(2',4'-dimethylphenylamino)-8-die the surface of the third paper and so on. By applying thylaminobenzcifluoran can be boiled with an alkali pressure or impact to the papers by means of a pencil, solution without being destroyed. a ball-point pen or a typewriter on the first paper, the 5. The present benzcifluoran compounds have good material on the back side and the electron-acceptor fastness to light, moisture and sublimation. substances on the surface of the papers are brought The obtained deep image on this recording sheet into contact with each other, whereby the colorless does not disappear or change in color by moisture or pressure-sensitive material moves to the electron droplets of water, or by exposure to sun-light or by acceptor layer and undergoes color development and heating. therefore colored images can be obtained. 55 The recording sheet prepared with use of the present The compound (II) has defects that, when used as benzc) fluoran compound endures storage for a long color precursor for pressure-sensitive copying paper, it period of time without the disappearance of the image stains capsules in undesired red color because it is on the documents and slips. slightly soluble in water or slightly acidic or alkaline 6. The present fluoran compounds have high color Wate. 60 developing speed. Such color formation occurs just at Further, it has a relatively high vapor pressure so that once when the fluoran compounds in the form of crys it tends to vaporize from the capsules to form ghost tals or a solution in the above-cited solvents are images which contaminate regular images on the pres brought into contact with the acidic electron-acceptor. sure-sensitive copying paper and to cause the images to Then, the recording sheet prepared with use of the disappear on the paper during storage for a long period 65 present benzcifluoran compounds gives vivid deep of time. images on the paper at the moment when a pressure or The present invention has technical advance over impact is applied onto the paper by means of a pencil, prior arts in the following points: a ball-point pen or a typewriter. 3,947,471 S 6 7. The images on the recording sheet prepared withia. chloride or bromide, anhydrous aluminum chloride or mixture of the present benzcifluoran, compounds do bromide, anhydrous, ferric chloride or bromide; phos not change in color owing to the same color-developing phoric pentachloride or bromide; phosphorous trichlo speeds caused by the same benzcifluoran nucleus. ride or bromide, and anhydrous hydrogen chloride or The present benzc) fluoran compounds represented by fluoride. Y the general formula (I) may be prepared by the follow If necessary, carbon disulfide, chlorinated benzenes, ing three methods. . . or nitrobenzenes are used as a solvent for the reaction. In the presence of a dehydrating agent, benzc) fluo The resulting xanthohydrol is converted to the fluo ran (I) can be prepared by reacting a o-(2'-hydroxy-4'- ran compound represented by the formula (I) by clos aminobenzoyl)-benzoic acid represented by the for 10 ing the ring...... , '' mula, t : After the reaction is over, the reaction mixture is poured into ice or water to separate solid, and if de sired, the mixture is neutralized with a solution of an OH alkali such as caustic soda, potassium hydroxide and 15 the like thereby to obtain the xanthohydrol. ">-C3-co-2'-R2 M In order to convert the resulting xanthohydrol to the COOH fluoran compound represented by the formula (I) by closing the ring, the xanthohydrol may be dissolved and wherein R, R2, Z and n are as defined above, with a heated in a solvent and then the mixture may be cooled compound represented by the formulas, 20 or concentrated to obtain the fluoran compound (I) as white crystals. R3 R4

Y1 RO N OR' 25 Yl or R3 Yl Y2 OR wherein R, R, Y, Y and A are as defined above and 30 R and R' represent hydrogen atom or a lower alkyl group, to obtain a 1 1-(o-carboxyphenyl)-2,8-diamino benz(c)-xanthohydrol represented by the formulas, 35

wherein R, R2, Ra, R, Y, Z and n are as defined above. ; ...... ; As a solvent for the ring-closure, aromatic hydrocar bon solvents such as benzene, xylene, etc.; nuclear 40 halogenated aromatic hydrocarbon solvents such as chlorobenzene, bromobenzene, dichlorobenzenes, tri chlorobenzenes, etc.; alcohols such as methanol, etha nol, etc.; amide solvents such as dimethylformamide, diethylformamide, etc.; sulfoxide solvents such as di 45 methylsulfoxide, diethylsulfoxide, etc.; aliphatic hydro O carbon solvents such as n-hexane, cyclohexane, etc.; halogenated aliphatic hydrocarbon solvents such as chloroform, bromoform, methylchloroform, etc.; and ethers such as dimethyl ether, diethyl ether, etc. are 50 useful. ". . . The cyclization is often facilitated by the addition of an aliphatic amine such as dimethylamine, trimethyl amine, diethylamine, triethylamine, etc.; an aliphatic aminoalcohol such as ethanolamine, propanolamine, 55 etc.; or a heterocyclic base substance such as pyridine, picoline, etc. White crystals, which separate on heating and cool ing in any one of these cyclization solvents or a mixture thereof, are filtered and washed with a nonpolar sol wherein R. R. R. R. Yi, Y, A, Z and n are as de 60 vent such as cyclohexane, n-hexane, diethyl ether to fined above, and by ring-closing the resultant. obtain a colorless compound (I). In case of a com The reaction may be effected at a temperature of 0° pound having a stable lactone ring, white crystals are to 300°C for several hours or sometimes for a few days often obtained merely by neutralizing a hydrochloric in the presence of a dehydrating-condensing agent. acid or sulfuric acid solution thereof with caustic soda, Examples of the dehydrating-condensing agent include 65 potassium hydroxide, etc. sulfuric acid; phosphorous pentoxide; phosphoric acid; The second method is similar to the first method. polyphosphoric acid; anhydrous metal halides such as Thus, a 2-(4'-amino-1'-hydroxy-2'-naphthoyl)-benzoic anhydrous tin chloride or bromide, anhydrous zinc acid represented by the formula, 3,947,471 7 8 OH COOH wherein R, R2, R1, Y1, A, Z and m are as defined above, which has at least one hydrogen atom in the 1, -e-Q amino substituent at 2-position of the benzc) fluoran N 2m nucleus is treated with an alkylating agent, an acylating 1 N. 5 agent or a sulfonylating agent as explained below in the R3 R4 presence or absence of a dehydrating agent or a dehy wherein Ra, R., Y, Z and m are as defined above, may drohalogenating agent. The reaction is properly carried be reacted with a m-aminophenol at a proper reaction out at 0 - 200°C for several hours or sometimes for a temperature in the presence of a dehydrating agent as few days, if desired, in the presence of a solvent such as explained above to obtain a benzcifluoran compound 10 benzene, toluene, xylene, chloroform, i.2-dichloroe represented by the general formula (). thane, ether, dioxane, N,N-dimethylformamide, di The reaction proceeds as follows: methylsulfoxide, alcohols, etc. The reaction proceeds as follows: 5 Y. R R OH N1 2 Y Yl R r - R O K O N{ . R2 - R3X->R3 N 2 R43)^co-3, OR. . RHN R 1. CO CO m 2m 25 Y. O NS-Rl or R3- R2 R4 PN O 30 CO

2n 35 wherein R, R, R2, Ra, R, Y, Z and n are as defined above. The purification procedure after the reaction is the same as that in the first method. The third method is accomplished by the use of a 40 fluoran compound prepared by the first or second methods. Thus, a benzcifluoran represented by the formulas, 45 Y.

l oa-KiR2 R4HN 0 50 CO 2m

55 O wherein R, R2, Ra, R1, Y1, Y, Z and m are as defined above and X signifies a residue of the alkylating, acylat ing or sulfonylating agent such as halogen atom, hy 60 droxy group, SOT, POs, etc. Examples of the acylating, alkylating and sulfonylat ing agents which may be used in the above-mentioned reaction include: . 65 Acetic anhydride Propionic anhydride Butyric anhydride Propiolic anhydride. 3,947,471 9 O Crotonic anhydride p-Nitrobenzyl bromide Benzoic anhydride o-Nitrobenzyl bromide m-Chlorobenzoic anhydride m-Chlorobenzyl bromide o-Chlorobenzoic anhydride p-Bromobenzyl bromide m-Nitrobenzoic anhydride 5 o-Bromobenzyl bromide p-Bromobenzoic anhydride m-Methylbenzyl bromide o-Bromobenzoic anhydride p-Methoxybenzyl bromide m-Methylbenzoic anhydride o-Methoxybenzyl bromide p-Methoxybenzoic anhydride 6. Allyl halides: o-Methoxybenzoic anhydride 10 Allyl chloride 2. 2-Methylallyl chloride Acetyl chloride 2-Ethylallyl chloride Propionyl chloride 2-Butenyl chloride Acryloyl chloride Cinnamyl chloride Methacryloyl chloride 15 7. Propargyl halide derivatives: Crotonoyl chloride Propargyl chloride Acetyl bromide 2-Butynyl chloride Butyryl bromide 2-Pentynyl chloride Propiolyl bromide 2-Pentynyl bromide Crotonyl bromide 20 3-Phenyl-2-propynyl bromide Benzoyl chloride 8. Dihalides: m-Chlorobenzoyl chloride o-Xylylene dichloride p-Nitrobenzoyl chloride m-Xylylene dichloride o-Nitrobenzoyl chloride p-Xylylene dichloride m-Bromobenzoyl chloride 25 4,5-Dimethyl-o-xylylene dichloride p-Methylbenzoyl chloride 3,6-Dimethyl-o-xylylene dichloride o-Methylbenzoyl chloride 4-Methyl-m-xylylene dichloride m-Methoxybenzoyl chloride 2,5-Dimethyl-m-xylylene dichloride Benzoyl bromide 4,6-Dimethyl-m-xylylene dichloride p-Chlorobenzoyl bromide 30 4-Hydroxy-5-methyl-m-xylylene dichloride o-Chlorobenzoyl bromide '. 2-Hydroxy-5-methyl-m-xylylene dichloride m-Nitrobenzoyl bromide 4-Bromo-6-methoxy-m-xylylene dichloride p-Bromobenzoyl bromide 2-Bromo-5-methyl-p-xylylene dichloride o-Bromobenzoyl bromide 2,5-Dimethoxy-p-xylylene dichloride m-Methylbenzoyl bromide 35 4,4'-Bis-chloromethyldiphenyl p-Methoxybenzoyl bromide 3,3'-Dimethyl-4,4'-bis-chlorodiphenyl o-Methoxybenzoyl bromide 4,4'-Bis-chloromethyldiphenylmethane Also, as the alkylating agent, the following CO- 3,3'-Dimethoxy-4,4'-bis-chloromethyldiphenylme pounds are preferable. thane ...... 3. Esters: 40 4,4'-Bis-chloromethyldiphenylethane Dimethyl sulfate : 3,3'-Dimethoxy-4,4'-bis-chloromethyldiphenyle Diethyl sulfate thane Dipropyl sulfate 4,4'-Bis-chloromethyldiphenylether Trimethyl phosphate 3,3'-Dimethyl-4,4'-bis-chloromethyldiphenylether Triethyl phosphate 45 4,4'-Bis-chloromethylstilbene Methyl benzenesulfonate 3,3'-Dimethyl-4,4'-bis-chloromethylstilbene Ethyl benzenesulfonate 3,3'-Dimethoxy-4,4'-bis-chloromethylstilbene Methyl p-toluenesulfonate 2-Butenylene dichloride Propyl p-toluenesulfonate 1,4-Dimethyl-2-butenylene dichloride Methoxyethyl p-toluenesulfonate. 50 1-Methyl-2-butenylene dichloride Methyl methanesulfonate 1-Ethyl-2-butenylene dichloride Propyl methanesulfonate 2-Butynylene dichloride 4. Lower alkyl halides: 1-Methyl-2-butynylene dichloride Methyl chloride o-Xylylene dibromide Methyl bromide 55 m-Xylene dibromide Ethyl bromide p-Xylylene dibromide . . Propyl chloride 4,5-Dimethyl-o-xylylene dibromide Butyl chloride 4-Methyl-m-xylylene dibromide 5. Benzyl halides: 2,5-Dimethyl-m-xylylene dibromide Benzyl chloride 60 4-Methoxy-m-xylylene dibromide m-Nitrobenzyl chloride 4-Hydroxy-5-methyl-m-xylylene dibromide p-Chlorobenzyl chloride 4-Chloro-6-methoxy-m-xylylene dibromide o-Chlorobenzyl chloride 2,5-Dimethyl-p-xylylene dibromide m-Bromobenzyl chloride 2,5-Dimethoxy-p-xylylene dibromide p-Methylbenzyl chloride 65 2-Bromo-5-methyl-p-xylylene dibromide o-Methylbenzyl chloride 4,4'-Bis-bromomethyldiphenyl m-Methoxybenzyl chloride 3,3'-Dimethyl-4,4'-bis-bromomethyldiphenyl Benzyl bromide 3,3'-Dimethoxy-4,4'-bis-bromomethyldiphenyl 3,947,471. s 12 4,4'-Bis-bromomethyldiphenylmethane. . . . . p-Chlorobenzenesulfonyl bromide 3,3'-Dimethoxy-4,4'-bis-bromomethyldiphenylme p-Nitrobenzenesulfonyl bromide thane 2 ...... ; p-Methoxybenzenesulfonyl bromide 4,4'-Bis-bromomethyldiphenylethane ...... As the dehydrohalogenating agent, 3,3'-Dimethyl-4,4'-bis-bromomethyldiphenylethane 5 Sodium hydrogen carbonate 3,3'-Dimethoxy-4,4'-bis-bromomethyldiphenyle Potassium hydrogen carbonate. thane ...... “...... Sodium carbonate - 4,4'-Bis-bromomethyldiphenylether ...... Potassium carbonate 3,3'-Dimethoxy-4,4'-bis-bromomethyldiphenylether Sodium acetate 4,4'-Bis-bromomethylstilbene ...... 10 Potassium acetate 3,3'-Dimethyl-4,4'-bis-bromomethylstilbene and 2-Butenylene dibromide ...... Caustic soda - 1,4-Dimethyl-2-butenylene dibromide : . . . . . may be used. Also, if circumstances permit, the basic 1-Methyl-2-butenylene dibromide : ...... substance used in the ring-closure, may be used. 2-Butynylene dibromide . . . . 15 As the solvent in the third method, aromatic hydro 1-Methyl-2-butynylene dibromide carbon solvents such as benzene, xylene, etc.; haloge 1,4-Dimethyl-2-butynylene dibromide nated aliphatic hydrocarbon solvents such as chloro 2,4-Hexadienylene dichloride form, bromoform, methylchloroform, etc.; halogenated 2,4-Hexadienylene dibromide aromatic hydrocarbon solvents such as chlorobenzene, p-Bromomethylbenzyl chloride 20 bromobenzene, dichlorobenzenes, etc.; alcohol sol 9. Alcohols: vents such as methanol, ethanol, propanol, etc.; ether o,o'-Dihydroxy-oxylene solvents such as diethyl ether, dimethylene glycol, di o,a'-Dihydroxy-m-xylene - methyl ether, diethylene glycol, etc.; sulfoxide solvents o,o'-Dihydroxy-p-xylene . . . . . such as dimethyl sulfoxide, diethyl sulfoxide, etc.; and o,o'-Dihydroxy-4-methyl-m-xylene ...... amide solvents such as N,N'-dimethylformamide, di o,0'-Dihydroxy-2,5-dimethyl-m-xylene methylacetamide, N-methylpyrrollidone may be used. o,0'-Dihydroxy-4-methoxy-m-xylene . Specific examples of the compounds of the general 4,4'-Bis-hydroxymethyldiphenyl- ...... formula (I) produced by the above-mentioned methods 4,4'-Bis-hydroxymethyldiphenylmethane . . . . according to the present invention which show excel 4,4'-Bis-hydroxymethyldiphenylethane . . . . lent resistance to water, good fastness to light and rapid 4,4'-Bis-hydroxymethylstilbene: . . .' " color developing speed are as follows. Shade on silica 1,4-Dihydroxy-2-butene gel after development for each compound is also shown 1,4-Dihydroxy-2-butyne ...... below. and the like dihydroxy compounds obtained by replac ing halogen in the dihalides as shown in (8) above by 35 shade after hydroxy group ...... Compound development 10. Ethers: . o,o'-Eimethoxy-o-xylene. 2-(N-Phenylamino)-8-diethylamino Bluish green-black o,o'-Dimethoxy-m-xylene benzcifluoran2-(N-Phenylmethanesulfonamido)-8- - : Dark red o,o'-Diethoxy-p-xylene . . . . 40 diethylamino-benzcifluoran and the like ether compounds obtained, by replacing 2-(N-Phenylamino)-8-dimethylamino Bluish green-black halogen in the dihalides as shown in (8) above by alkyl 4'-nitrobenzcifiuoran2-(N-Phenyl-benzamido)-8-dibenzyl Dark red ether group i: , , , , ; ; , - aminobenzcifluoran2-(N-Phenylamino)-3-methoxy-8- Bluish green-black 11. Acrylonitrile . diethylaminobenz(cfluoran Acrylamide , 45 2-(N-a-Naphthylamino)-8-diethyl Bluish green aminobenzcifluoran 12. Sulfonylating agents: 2-(N-3-Naphthyl-p-toluenesulfon Dark red Methanesulfonyl chloride: . . amido)-8-dimethylamino- : Ethanesulfonyl chloride benzcifluoran Propanesulfonyl chloride 2-(N-4-Methoxy-1-naphthylamino)-8- Bluish green-black Butanesulfonyl chloride" 50 diethylamino-benzcifluoran2-(4-Methylphenylamino)-8-dimethyl- - Green• . Benzenesulfonyl chloride amino-benz(cfluoran p-Toluenesulfonyl chloride 2-(4'-Methylphenylamino)-8-diethyl Green 2-(2'-Methoxyphenylamino)-8-amino-benzcifluoran - . . . . . Greenish black m-Toluenesulfonyl chloride. dimethylamino-benz(cfluoran o-Toluenesulfonyl chloride 2-(2'-Methoxyphenylamino)-8- Greenish black p-Chlorobenzenesulfonyl chloride. . 55 diethylamino-benzcifluoran 2-(2',4'-Dimethylphenylamino)- Green m-Chlorobenzenesulfonyl chloride, 8-dimethylamino-benzcifluoran o-Chlorobenzenesulfonyl chloride . . . . . 2-(2',4',6'-Trimethylphenylamino)- Green p-Nitrobenzenesulfonyl chloride, ; ; ; c. 8-dimethylamino-benzcifluoran m-Nitrobenzenesulfonyl chloride ...... 2-(2'-Methyl-4'-chlorophenyl Green 60 amino)-8-dimethylamino-benz o-Nitrobenzenesulfonyl chloride : . . . c fluoran 2-(2'-Methyl-4'-chlorophenyl Green p-Methoxybenzenesulfonyl chloride ...... amino)-8-diethylamino m-Methoxybenzenesulfonyl chloride is . . benzcifluoran 2-(4'-Chlorophenylamino)-8- Green o-Methoxybenzenesulfonyl chloride dimethylamino-benz(c) fluoran and bromides thereof such as, for example, 2-(4'-Chiorophenylamino)-8- Green Methanesulfonyl bromide. 65 diethylamino-benzic) fluoran 2-(2',4',6'-Trimethylphenylamino)- Green Ethanesulfonyl bromide 8-dimethylamino-4' (or 5')- Benzenesulfonyl bromide chloro-beinzc fluoran p-Toluenesulfonyl bromide . . 2-(2',4',6'-Trimethylphenylamino)- Green 3,947,471 15 16 sorbed in the absorber. After dissolution, the mixture was prepared from 4-(4'-methylphenylamino)-1-naph was warmed to 25 to 30°C for 5 hours. After cooling, thol and 2-(2'-hydroxy-4'-diethylaminobenzoyl)-ben the reaction mixture was then poured into 700 g of zoic acid. ice-water at 10 to 20°C. The mixture was neutralized Yield: 45.6%. This compound formed green color on with an aqueous caustic soda solution at the same tem- 5 silica gel with good fastnesses to light and moisture. perature. The precipitate was filtered and washed with water. EXAMPLE 3 The thus obtained solid 1 1-(2-carboxyphenyl)-2-(2',- According to the same method as in Example 1, 4',6'-trimethylphenylamino)-8-diethylaminobenzc 2-(2'-methoxyphenylamino)-8-diethylamino-benzc xanthohydrol was dissolved in 400 g of chloroform and 10 fluoran represented by the formula, dehydrated with 50 g of anhydrous sodium sulfate. After addition of 5g of active charcoal, the chloroform solution was filtered while hot. The filtrate was concen trated under reduced pressure to obtain the crystals. Thus, 2-(2',4',6'-trimethylphenylamino)-8-die- 15 thylaminobenzc) fluoran represented by the formula, o O ér CO

O 20 fC CO was prepared from 4-(2'-methoxyphenylamino)-1- CH3 CH3 naphthol and 2-(2'-hydroxy-4'-diethylaminobenzoyl)- was obtained as white crystals in a yield of about 55.6.25 benzoic acid. This derivative having a melting point of %. 231 to 233°C formed dark greenish black color on Melting point: 225°- 226°C silica gel and had visible sepctrum An F462.5 mpu and Visible spectrum Ana = 441 mu, 465.5 mu and 630 617.5 mpu (acetic acid). impu (acetic acid) The resulting compound formed dark green color on 30 EXAMPLE 4 contacting with silica gel when used as a material for In the same manner as in Example 1, 4-(2',4'-dime pressure-sensitive copying paper. The image having thylphenylamino)-1-naphthol and 2-(2'-hydroxy-4'- excellent fastnesses to light, moisture, sublimation and diethylaminobenzoyl)-benzoic acid was reacted to pro alkali was produced. duce 2-(2',4'-dimethylphenylamino)-8-diethylamino 35 EXAMPLE 2 benzc-fluoran in the form of white crystals having a melting point of 147 to 148°C and a visible spectrum By use of the same procedure as in Example 1, 2-(4'- An = 463.0 mu and 620 mu (acetic acid). This com methylphenylamino)-8-diethylamino-benzcifluoran pound formed dark green color on silica gel and did not represented by the formula, change in color during storage for a long period of 40 time.

EXAMPLE 5 HN O In the same manner as in Example 1, the following o CO 45 compounds were synthesized. Shade on silica gel is CH3 shown on the right hand column.

Benzoyl Naphthyoming benzoic acid Product Shode

Oh OH (y-n 1 is Bluish gre on COOH

OH ch, ,-C-co-) NH Green COOH CH

OH N(CH) NH Wiolet NH COOH 3,947,471 14 13 duplicated image on contact. with the electron-accep -continued tor. In another system as disclosed in U.S. Pat. No. Shade after 2,730,457, a coating liquid containing both of the cap Compound development sules chromogenic material and acidic material is ap 8-diethylamino-4" (or 5')- plied on one side of a sheet or alternatively, a coating chloro-benzc fluoran 2-(N-Phenylacetylamino)-8- Red containing capsules is first applied on one side of a diethylamino-benz(c) fluoran sheet and the second coating containing the electron 2-(N-(2',4'-Dimethylphenyl)- Red acetylamino)-8-diethylamino acceptor is applied thereon. Thus, all the components benzc fluoran are disposed on a single sheet, the record material is 2-N-(2',4',6'-Trimethylphenyl)- Red 10 actylamino)-8-diethylamino referred to as “self-contained' system and develops benzcifluoran image color when the pressure is applied. N-(8-Aminobenz(c) fluoran-2-yl)- Purplish blue-black As a modification of pressure-sensitive marking sys N-(6-aminofluoran-2-yl)amine N-(8-Methylaminobenzc) fluoran Purplish blue-black tem, Japanese Patent No. 51 1,757 (corresponds to 2-yl)-N-6-methylamino U.S. Pat. Application Ser. No. 392,404, filed on Aug. fluoran-2-yl)methylamine 15 . N-(8-Dimethylaminobenzic fluoran Purplish blue-black 27, 1964) discloses a recording sheet, in which minute 2-yl)-N-3-methoxy-6-dimethyl capsules containing liquid solvent are coated on one amino-fluoran-2-yl)benzylamine surface of a sheet support and both of the chromogenic N-8-Dimethylaminobenzc fluoran Dark purplish blue 2-yl)-N-(6-dimethylamino material and the acidic polymer are coated on or im fluoran-2-yl)acetamide pregnated in same sheet or other sheet in solid condi N-8-Dimethylamino-3'-nitrobenz Dark purplish blue 20 c) fluoran-2-yl)-N-(6-dimethyl tion. - amino-3'-nitrofluoran-2-yl)- There is thermo-responsive record sheet as a mark benzenesulfonamide forming system utilizing an electron donor-acceptor 2-(N-6-Naphthylamino)-3',6'- Green dichloro-8-dimethylamino color-forming reaction. For example, Japanese Patent benz(c) fluoran . No. 45-14039 (corresponds to U.S. Pat. Application 25 Ser. No. 554,565 filed on June 1, 1966), discloses a temperature-responsive record material comprising a As used in mark-forming systems, marking in desired supporting sheet material having crystal violet lactone areas on support webs or sheets may be accomplished and a phenolic material solid at room temperature but by effecting localized reactive contact between the capable of liquefying and/or vaporizing at normal ther chromogenic material and the acidic material on or in 30 mographic temperatures, said lactone and phenolic such web or sheet, such chromogenic material being material being further capable of producing a mark brought thereto by transfer, or already present therein, forming reaction upon reactive contact. the reactive contact forming a clear coloration in the The novel compounds of our invention are widely intended image-marking areas. used for the above-mentioned mark-forming systems as There have already been known several types of 35 a colorless chromogenic compound, i.e. electron donor recording system utilizing an electron donor-acceptor and gives many excellent advantages. color-forming reaction between chromogenic material According to the present invention, the above-men and acidic, material. 4. tioned known techniques for the production of the The pressure-sensitive recording systems generally recording sheet are utilized using the above-mentioned comprise color-forming components on and/or within 40 fluoran compounds as a coloring material alone or in one or more sheet supports, the color-forming compo admixture with various known coloring materials to nents being isolated from one another by a press obtain the recording sheet which can form red, green urerupturable barrier. Where the color-forming com or black color. ponents are disposed on separate sheets as disclosed in Also, it is effective for improving the color forming U.S. Pat. No. 2,712,507, the record material referred 45 property and fastnesses to light and moisture of devel to as a “transfer" or “couplet' system. In such system, oped images to use a metal or metallic compound to a solution of a chromogenic material is held in ruptur gether with the electron-acceptor. able microscopic capsules coated onto one surface of a Thus, metals or metallic compounds such as manga transfer sheet, while an adjacent receiving sheet is sen nese, nickel, cobalt, iron, zinc, copper, cadmium, mer sitized with an acidic material, i.e. an electron accep 50 cury, silver, platinum, etc. are effective. Specific exam tor. Most common acidic materials are activated acid ples of the metallic compounds include salts and acid clay and acid clays, such as attapulgite, zeolite, benton salts such as copper sulfate, ferrous sulfate, manganese ite, kaolin and silica. Recently, monomeric phenols or sulfate, cobalt sulfate, zinc sulfate, nickel acetate, etc.; acid reactant polymeric materials, such as phenolic basic salts such as cadmium hydroxide; and oxides such polymers, phenyl-acetylene polymers, maleic acid 55 as zinc oxide. They show particularly good results. rosin resins, have been suggested either alone or in The present invention will be further specifically combination with acid clays. explained below referring to the following examples In the manufacturing method of such record mate which do, of course, not limit the scope of the present rial, for instance, a non-volatile oil containing a chro invention. mogenic material dissolved therein is protected by 60 EXAMPLE 1 encapsulation with coacervate film of a water-soluble polymer. The resulting coating composition containing 140 Grams of 95% sulfuric acid was charged into a dispersed capsules are coated on one side of a sheet, four-necked flask provided with a stirrer, a thermome and coating composition of said electron acceptors is ter and a hydrogen chloride gas absorber. A mixture of coated on the other side of the sheet. When several 65 28.0 g of 4-(2',4',6'-trimethylphenylamino) 1-naphthol sheets are load one over another and impressed with a and 31.3 g of o-(2'-hydroxy-4'-diethylaminobenzoyl)- pencil or the like, capsules are collapsed to release the benzoic acid was added for one hour below 25°C. At oil containing chromogenic material which produces a that time, the hydrogen chloride gas evolved was ab 3,947,471 17 18 - Continued enzoyl Nophthylamine benzeic acid Produce Shee

O oh och o NHCH, N c.,n-CS cos) ? N Greenish block e O 3 coch cho CO

ch O . c", N(CH), o N YCD (CH), N -(-cos)cooH No. C N Olo Dork red

No.

co N-y-CH ch ch=CHCH2s 2 N(CH3CH) 3 8 3 c.c., n-s-co- na N O Dark red CH-CH=CH Coo f CH co

O N(CH2CHOCH) uish HC N (CHOCHCH), N co-Ky-och, N - green -block cod- C

o N(CH-Y 2 Dark rod 8.8 ((Y-ch.), N- S-cosy HCN O ch cooh o

N us d N o (c,c,,-CS- co o green-block cool d d

EXAMPLE 6 8.12 Grams of 2-phenylamino-8-die thylaminobenzcifluoran and 21.4 g of benzyl bromide were maintained in 50 g of N,N-dimethylformamide at 70 to 80C in the presence of sodium carbonate for 3 hours. The reaction mixture was then poured into ice water to form precipitate, which was filtered and ex was obtained as white crystals. Yield: 80%. The prod tracted with chloroform. The chloroform solution was 55 uct was recrystallized from a benzene-cyclohexane washed with aqueous sodium carbonate and then with mixture. This compound formed red color on silica gel. water several times and dried over anhydrous sodium sulfate. The extract was concentrated to obtain a syr EXAMPLE 7 upy product which was then filtered. , . . . In the same manner as in Example 6, the compounds Thus, 2-(N-phenyl-N-benzylamino)-8-die 0 of the following formulas were obtained. Shade on thylaminobenzcifluoran represented by the formula, silica gel is shown in the right hand column.

fluoron compound Product m She de

N C25 2. c an er" derk red c 3,947,471 19 20 -Continued Product Shads flu or on compound

CH=CHCH, Br dark red

N(CH2CHOCH2CH) cher Dark purplish O 2 red

O N(CHCHCI 2 CH - y-o S O N(C HCHCI 2 NH O CH-Y- Soci 3. 2 S" Dark red CS lo - Co

(CH), N O n (c. Hs), O N(C2H5)2 d O dark red

CCs CO

Cyc H.'? B f Redviolet

CH=CHCH Red CH=CH-C HBr violet

45 N(C2H5)2 EXAMPLE 8 CH3CON1 - 10 Grams of 2-(4'-chlorophenylamino)-8die- 50 c thylamino-benz(c) fluoran was heated at about 140°C Cl for 3 hours together with 30 g of acetic anhydride. was obtained in a yield of 56.0%. This compound After the reaction was completed, the unreacted acetic formed red color on silica gel. anhydride was removed by steam distillation to form a solid which was filtered. The solid was then recrystal-55 EXAMPLE 9 lized from chloroform. Thus, 2-N-(4-chlorophenyl)- In the same manner as in Example 8, the compounds acetylamino)-8-diethylamino-benzcifluoran repre of the following formulas were obtained. Shade on sented by the formula, silica gel is shown in the right hand column.

". . . . . Flu oran compound a a

O Nich, 2

21 3,947,471 The procedures of the preparation of recording sheets are illustrated by the following examples. Compound Shode EXAMPLE A O N(CHCI) In 200 g of dichlorodiphenyl was dissolved 6 g of 5 2-(2',4', 6'-trimethylphenylamino)-8-die CHSoN O Red thylaminobenzcifluoran represented by the formula, CO

O O. N(CH2CH)

NH Green cif, CH3 CO CO 15 The resulting solution was mixed vigorously at 40°C with 360 g of a 1 1.0% aqueous gelatin solution to make N(CH3) an emulsion. To the resulting emulsion, 300 g of a 10% NH Bluish green aqueous gum arabic solution was added. Acetic acid 20 O? black was added to the mixture at 40°C with stirring to adjust co the pH value to 5, and water was then added to effect the coacervation of the system, whereby oil droplets containing the above-mentioned benzc) fluoran com pound were coated by the coacervated liquid wall of a 25 O N(CH3), complex of gum arabic and gelatin. At 5°C, the pH CHCH6's 2n value of the system was further reduced to 4.4 and 5g (1 dark red of 35% formalin was added to harden the wall. In order co to complete microencapsulation, 10% sodium hydrox ide was added to increase the pH value to 9 and the 30 whole system was then gradually warmed to 50°C. The coating composition containing the thus prepared mi O N(CH ) CH 25 2 crocapsules was applied onto paper in a conventional NH manner. This paper was faced to the second paper onto er C Green which active clay or a phenylphenol-formaldehyde 35 lo resin had been applied together with a binder. A dark green image was instantly formed on the second paper by applying pressure by means of a pencil. The thus obtained green image did not change in color and 40 showed good fastnesses to light, water and heat. Greenish EXAMPLE B block According to a procedure similar to that of Example A, similar pressure-sensitive copying paper was pre pared from 6 g of 2-(N-phenyl-p-toluenesul 45 fonylamino)-8-diethylamino-benzc) fluoran repre sented by the formula, Bluish green block 50

(Y-ch CO O N(CH2CH2OCH) 55 2n X w o dork red Red image was obtained by the application of pressure CO by handwriting. The thus obtained red color had good CH fastnesses to light, water and heat. 60 EXAMPLE C

By the same procedure as in Example A, similar C.3 ChechCH 2 pressure-sensitive copying paper was obtained from the SN Dark purplish following color precursors. The properties and fast nesses of the pressure-sensitive copying paper were the 65 same as in Example A: 3,947,471 23 24 diethylaminofluoran were used as electron donating Compound Shade color formers. EXAMPLE G (CH), N C O N(CH3) 5 In 100 parts by weight of trichlorodiphenyl, 4 parts toluish black by weight of 2-(2-methyl-4'-methoxyphenylamino)-8- CO H CC diethylamino-benzc) fluoran was dissolved at 100°C. The color former-containing oil was dispersed in a mixture of 500 parts by weight of a 10% gelatin solu 10 tion and 500 parts by weight of a 10% gum arabic O Nichs), solution at 60°C to form an emulsion. Then, 1,000 parts NH Buish by weight of warm water at 40°C was added to dilute green-black the emulsion. O slo A 10% acetic acid solution was gradually added 15 dropwise at 50°C with stirring to adjust the pH value to Br 4 - 4.3. The emulsion was cooled to a temperature below 15°C. At this temperature, 500 parts by weight ( of a 20% dispersion of titanium oxide having a particle (Y-cos O N chch 2 size of 0.2 to 0.4 pu, was added and 100 parts by weight Or dark red 20 of a 10 % formalin was then added. Further, 10% O caustic soda was gradually added dropwise to adjust the pH value to 10 - 10.5. The thus obtained dispersion is referred to as “A liquid'. On the other hand, 40 parts by weight of 10% caustic chan N(CH), ... 25 soda and 200 parts by weight of activated clay were N Dark red dispersed in 400 parts by weight of water. Then, 200 parts by weight of a 10% polyvinyl alcohol was added. The thus obtained dispersion was uniformly mixed with the above-mentioned A liquid to obtain a coating com 30 position. (CH3CH2)2N O O N(CH2CH3)2 The coating composition was applied onto one side O l O Buish of 40 g/m paper in an amount of 7 g/cm on dry basis green -black and then dried. The resulting pressure-sensitive copy co h CC ing paper is a “self-contained' type. When pressure 35 was applied onto the coated surface, blackish green color was formed which did neither change nor disap pear on exposure to light or moisture. EXAMPLE D EXAMPLE H In the same manner as in Example A, pressure-sensi- 40 The capsule-containing coating liquid as prepared in tive copying paper was prepared using 2-(2',4'-dime Example G was applied onto one side of 45 g/m' paper thylphenylamino)-8-dimethylamino-benzc) fluoran as in an amount of 5 g/mon dry basis and dried. Further, an electron donating color former and activated clay as the electron-acceptor containing coating liquid as pre an electron-acceptor. Copied image obtained on the pared in Example A was applied onto the coated sur electron acceptor-coated surface was dark green in 45 face in an amount of 4 g/m' and dried. The resulting color and showed excellent fastnesses to light and mois pressuresensitive copying paper is a "self-contained' ture like that of Example A. type containing both a color former capsule-coated layer and an electron-acceptor-coated layer on one EXAMPLE E side of the paper. Pressure-sensitive copying paper was prepared in the 50 Good pressure-sensitive copying paper can be pre same manner as in Example A except that 3 parts by pared by replacing the electron-acceptor-containing weight of 2-(2',4',6'-trimethylphenylamino)-8-die coating liquid used in the above-mentioned examples thylamino-benzcifluoran and 3 parts of 2-dime by coating liquids of the following recipes: thylamino-8-dipropylamino-benzcifluoran, which 55 may form dark reddish violet color, as electron donat Parts by weight ing color formers were dissolved in 100 parts by weight (a) Water 100 of trichlorodiphenyi. Copied image obtained on the Acid clay 100 electron-acceptor surface was black in color and main Cadmium hydroxide 10 Styrene-butadiene latex 20 tained the original color during storage for a long pe (b) Water 200 riod of time. 60 Acid clay 100 Manganese sulfate 5 Styrene-butadiene latex 15 EXAMPLE F (c) Water 200 Pressure-sensitive copying paper, which may form Acid clay 100 Copper sulfate 3 black color images was obtained in the same manner as 65 Latex 10 in Example E except that 3 parts by weight of 2-N- (d) Water 200 Acid clay 100 (2',4'-dimethoxyphenyl)-aminol-8-methylamino Ferrous sulfate 3 benzc)-fluoran and 3 parts by weight of 2-methyl-6- Latex 5 3,947,471 2S -continued Parts by weight (e) Water 200 Acid clay 100 Zinc acetate O Latex 20 (f) Water 200 Acid clay W 00 Cobalt sulfate 5 Latex 15 (g) Water 200 Acid clay OO Nickel sulfate 5 Latex . 5 (h) Water 200 EXAMPLE K Attapulgite 100 Zinc oxide 5 Latex 15 A thermo-responsive (or heat-sensitive) recording 15 material is manufactured by the following manner. 20 Parts by weight of 2-(2',4'-dimethoxyphenylamino)-6- diethylamino-benz(c) fluoran, 15 parts by weight of EXAMPLE I 3-diethylamino-6-methylfluoran, 150 parts by weight of a 10% aqueous solution of polyvinyl alcohol, and 65 In 100 parts by weight of trichlorodiphenyl, 4 parts 20 parts by weight of water were dispersed in a high shear by weight of 2-(2',4'-dimethylphenylamino)-8- mixer. (Component A). 35 Parts by weight of Bisphe ethylamino-benzcifluoran was dissolved at 100°C. nol A, 150 parts by weight of the polyvinyl alcohol The color former-containing oil was dispersed in 500 solution, and 65 parts by weight of water were dis parts by weight of a 7% gelatin solution at 60°C to form persed in a high shear mixer. (Component B). 3 Parts an emulsion. To the emulsion, 350 parts by weight of a 25 by weight of Component A and 67 parts by weight of 10% gum arabic solution was added and 550 parts by Component B were combined and coated on the paper weight of warm water was added. A 10% acetic acid sheet at a dry weight of 5 g/m. The resulting sheet may solution was gradually added dropwise at 50°C with be used alone as a copy-receiving sheet by being served stirring to adjust the pH value to 4.0 - 4.3 and the with a pattern of heat from front or back, as by a ther emulsion was cooled to a temperature below 10°C. 200 30 mographically-heated original document, by trace of Parts by weight of a 50% dispersion of titanium oxide hot stylus, by hot type, or by any other means giving a having a particle size of 0.2 to 0.5 L was gradually heat pattern by conduction. Developed image of this added at this temperature with stirring. 38 Parts by sheet is clear black. weight of 37% formalin was then added and a 10 % What is claimed is: caustic soda solution was added dropwise to adjust the 35 1. A compound represented by the formula: pH value to 10.0 to 10.5. The thus obtained dispersion is referred to as "A liquid'. On the other hand, 20 parts by weight of zinc oxide and 40 parts by weight of a 28% ammonia water was added to 400 parts by weight of water. Then, 200 parts by weight of acid clay was dispersed in the mixture and one part by weight of sodium aiginate was added. Fur ther, 100 parts by weight of a 10% polyvinyl alcohol solution was added and the whole was well mixed. The resulting dispersion was mixed with the above-men tioned A liquid and 250 parts by weight of a 10 % polyvinyl alcohol solution and 100 parts by weight of pulp powder to form a coating composition. This coating composition was applied onto one side of 40 g/m paper in an amount of 10 g/mon dry basis and dried. The thus obtained pressure-sensitive copy ing paper is so-called "self-contained' type copying wherein R and Reach signify a lower alkyl group, R paper. Dark green image could be instantly formed by signifies hydrogen, Y signifies hydrogen, a lower alkyl the application of pressure and the obtained image did or lower alkoxy group, and m is an integer of 1 to 3. neither change in color nor disappear on exposure to 55 2. A compound represented by the formula, light or moisture.

O N(CH3)2 EXAMPLEJ CH3 60 Similar pressure-sensitive copying paper could be prepared by replacing 2-(2',4'-dimethylphenylamino)- CH3 CH3r 8-diethylamino-benzcifluoran used in Example I by the following fluoran compounds. Shade of the image obtained is shown in the right hand column. 65 3. A compound represented by the formula, 3,947,471 27 28 7. A compound represented by the formula, CH3 O N(CH3)2 f NH g O N(CH3)2 CO 5 OCH3 CH3 NH O 4. A compound represented by the formula, CO

O 8. A compound represented by the formyla,

:20

25.

30.

35.