US3901918A

US3901918A - Fluoran compounds

Info

Publication number: US3901918A
Application number: US301490A
Authority: US
Inventors: Koichi Koga; Yukiaki Ito
Original assignee: Sumitomo Chemical Co Ltd
Current assignee: Sumitomo Chemical Co Ltd
Priority date: 1971-10-29
Filing date: 1972-10-27
Publication date: 1975-08-26
Anticipated expiration: 1992-08-26
Also published as: JPS4933714A; DE2253161A1; JPS5125170B2; JPS5033891B2; JPS4931412A; JPS512010B2; JPS5127164B2; JPS4912918A; JPS512009B2; IT966700B; JPS5127166B2; JPS4887910A; JPS4922205A; GB1408200A; JPS4933715A; JPS5127167B2; JPS4931413A; FR2161937A1; JPS4883915A; NL7214690A

Abstract

Novel fluoran compounds such as 2-bis-(5'',6'',7'', 8''-tetrahydro2''-naphthylmethyl)amino-6-diethylaminofluoran and 2-(2''thenylamino)-8-dimethylbenz(c)fluoran, which are useful as a coloring material for record material systems, such as pressuresensitive copying paper or heat-sensitive copying paper, wherein colored images formed by an electron-donor-acceptor color-forming reaction between coloring material and acidic material.

Description

[ 1 Aug. 26, 197 5 221 Filed:

[ FLUORAN COMPOUNDS [75] Inventors: Koichi Koga, Toyonaka; Yukiaki Ito, Minoo, both of Japan [73] Assignee: Sumitomo Chemical Company,

Limited, Osaka, Japan Oct. 27, 1972 [21] Appl. No.: 301,490

[30] Foreign Application Priority Data Oct. 29. 1971 Japan 46-86643 Dec. 27, 1971 Japan.... 46-1074 Feb. 10, 1972 Japan.... 47-14663 Feb. 24 1972 Japan.... 47-19187 Apr. 13, 1972 Japan 47-37433 May 17, 1972 Japan 47-49375 June 22, 1972 Japan 47-63031 July 17, 1972 Japan 47-71844 July 17,1972 Japan 47-17845 July 28. 1972 Japan 47-76199 July 28. 1972 Japan 47-76198 [52] US. Cl. 260/335; 117/362; 117/368;

260/240; 260/247.2 R; 260/268 PC; 260/293.58; 260/295 T; 260/304; 260/306.8 R; 260/307 R; 260/307 D; 260/310 R; 260/326.l3 R; 260/326.36; 260/330.5; 260/332.2 H

[51] Int. Cl. C07D 311/96 [58] Field of Search 260/335 [56] References Cited UNITED STATES PATENTS 3,501,331 3/1970 Kimura et a1 260/335 FORElGN PATENTS OR APPLICATIONS 4640.079 3/1971 Japan Primary Examiner-Norma 8. Milestone Attorney, Agent, or Firm-Stevens, Davis, Miller & Mosher [5 7 1 ABSTRACT Novel fluoran compounds such as 2-bis-(5',6',7', 8'- tetrahydro-Z-naphthylmethyl)amino-6- diethylaminofluoran and 2-(2'-theny1amino)-8-dimethy1benz[c]fluoran, which are useful as a coloring material for record material systems, such as pressuresensitive copying paper or heat-sensitive copying paper, wherein colored images formed by an electrondonor-acceptor color-forming reaction between coloring material and acidic material.

3 Claims, No Drawings 1 FLUORAN COMPOUNDS In order to eliminate the inefficiencies and defects of a the oil carbon paper, pressure-sensitive copying paper or noncarbon paper, which is economic and handy, has recently made its debut in place of the oil carbon paper complying with demand for speed-up of office works.

Heretofore, leueoaurarnines, leucomethyleneblues, phthalides and fluorans are well known as color precursors. They are colorless or nearly colorless compounds, which may change to a certain coloring matter when they are brought into contact with acidic electronacceptor as explained below.

For example, 2-methyl-6-diethylamino-fluoran having the following formula is one of the well-known color precursors which are colorless compounds under ordinary condition but change to red coloring matters by opening their lactone ring when they are brought into contact with acidic electron-acceptor.

The pressure-sensitive copying paper is usually prepared by coating a back side of one sheet of paper with a color precursor such as a leucoauramine or a fluoran, and coating a surface of another sheet of paper with an acidic electron-acceptor substance such as kaolin, bentonitc, activated clay, acid clay, aluminum silicate, attapulgite, metal oxides, metal chlorides, metal sulfates, organic acids such as phenols, aliphatic acids or tannic acid, or phenolic resins such as p-phenylphenolformaldehyde resin, p-cyclohexylphenylformaldehyde resin, etc. The pressure-sensitive copying paper is used by placing the coated papers upon one another so that the back side of the first paper may be faced to the surface ofthe second paper, and the back side of the second paper to the surface of the third paper and so on. By applying pressure or impact to the papers by means of a pencil, a ball-point pen or a typewriter on the first paper, the material on the back side and the electron accep'torsubstances on the surface of the papers are brought into contact with each other, whereby the colorless pressure-sensitive material moves to' the electron-acceptor layer and undergoes color development and therefore colored images can be obtained.

The aforesaid compound has defects that, when used as color precursor for pressure-sensitive copying paper, it stains capsules in undesired red color because it is slightly soluble in water or slightly acidic or alkaline water.

Further, it has a relatively high vapor pressure so that it tends to vaporize from the capsules to form ghost images which contaminate regular images on the pressure-sensitive copying paper and to cause the images to disappear on the paper during storage for a long period of time.

Thus, an object of the present invention is to provide a novel chromogenic material without aforesaid defects.

This object can be accomplished by providing a novel fluoran represented by the following formula (I), (ll), (lll), or (IV),

(II-I) wherein R, and R each represents hydrogen atom. a lower alkyl group, a lower alkyl group substituted by halogen atom, lower alkoxy group or hydroxyl group, benzyl group or a benzyl group substituted by lower alkvl group, lower alkoxy group, halogen atom or nitro group as substituent R R represents a general formula.

R l H c 0 1 I l 085 R2 R4 provided that when R signifies I V C --(R A is naphthalene l R nucleus is (fight S5 Q'- gln [Kg- 10M -CH2-CH=CHCOOR12 9 n l0)n' N 414 -4 -13 (Rgl wm-U- (R l WW (R9),

wherein R R and R, each represents hydrogen atom, a lower alkyl group, a halogen atom, a lower alkyl group substituted by halogen atom, lower alkoxy group or hydroxyl group, or phenyl group which may be substituted by lower alkoxy group, lower alkyl group, halogen atom or nitro group; R represents hydrogen atom, a lower alkyl group or an acyl group; R and R each represents hydrogen atom or a lower alkyl group, R,, represents hydrogen atom, a lower alkyl group or benzyl group; R,, and R each represents hydrogen atom, a lower alkyl group, a lower alkoxy group, halogen atom, nitro group, amino group, an amino group substituted by lower alkyl group, lower alkoxy carbonyl group, a lower alkanesulfonyl group or benzenesulfonyl group which may be substituted by at least one Ry, R represents a lower alkyl group, a halogenated lower alkyl group, an aralkyl group or an aralkyl group substituted by R,; R and R13 represent hydrogen atom, a lower alkyl group, a halogenated lower alkyl group, phenyl group, aralkyl group, or phenyl or aralkyl group substituted by R.:' R represents hydrogen atom, a lower alkyl group, benzyl group or an acyl group; D represents a divalent radical, -O-, S or (R has the above-defined meanings); W represents D or --CH,; B represents pyridine or quinoline nucleus; P represents direct bond, or a divalent radical,

formula,

@- (R9 in -cn -ca=cu Q R, represents R,,, or R,', R R, and R each represents R R or R,,,; R, and R, each represents R phenyl group or a phenyl group substituted by R,; R (COL- OUR PRECURSOR NO. each represents R,,, R, or R,,,; andR and R R, and R, and R, and R may form a ring with a divalent radical, -(CH ),,W--'(CH CH2 C (R, is the same as defined above), wherein q r is 3 or 4; W is the same as defined above provided that W does not represent -CH in the case where A is benzene nucleus and q r= 4; n and n is an integer of l to 7; r is un integer of l to 2; Y, represents hydrogen atom, a lower alkyl, a lower alkoxy, a halogen atom such as fluorine, chlorine, bromine and iodine, amino group, or an amino group substituted by at least one lower alkyl group or nitro group; 2 stands for hydrogen atom, a lower alkyl, halogen atom such as fluorine, chlorine,

bromine and iodine, lower alkoxy, nitro or amino group, or an amino group substituted by at least one lower alkyl groups, or groups of the formula,

(wherein R and R each represents hydrogen atom, a lower alkyl, phenyl, halophenyl, methoxyphenyl or nitrophenyl); m is an integer of l to 4; A represents benzene or naphthalene nucleus, and Y, signifies phenyl, cyclohexyl, or benzyl group.

Throughout the present specification, the term lower" as is seen in "lower alkyl group" indicates that the number of carbon atoms is from 1 to 4.

Acyl group represents a group R'-CO in which R is an alkyl group having l to 3 carbon atoms, or benzoyl group which may be substituted by an aliphatic group having I to 4 carbon atoms or by R,.

The present invention has technical advance over prior arts in the following points:

1. These fluoran compounds represented by the general formulas (l), (ll), (ill) and (IV) are colorless and stable in air at ordinary temperature, but the compounds (I), (ll), ("1) and (IV) change in color from white to red, green or black when they are brought into contact with an acidic electron-acceptor explained above.

2. These fluoran compounds (I), (ll), (Ill) and (IV) show all sorts of dark colors, for example, deep red, dark green, dark blue-green, dark greenish black, or black according to the number, kind and position of substituents.

It is also possible to use the said compounds together with other color precursors such as C.V.L. (crystal violet lactone), B.L.M.B. (benzoyl leucomethylene-blue) or 2-tert-butyl-4-methyl-6-diethylaminofluoran, etc., to obtain a special color such as blue-black or black image on the paper without spoiling the other color precursors. These are significant features of the present invention.

3. These fluoran compounds are well soluble under colorless condition in a non-volatile non-polar solvent used for preparing a recording sheet. Examples of the non-polar solvent are as follows:

Cresylacetate, l-phenyl-3-methyl-indane, l,ldiphenylethane, bis-(a-methylbenzyl)benzenes; alkylated benzenes; alkylated naphthalenes such as dimethylnaphthalenes anddipropylnaphthalenes; mineral oil; paraffin oil; olive oil; and tricresyl phosphate, etc.

Good solubility particularly in the aromatic solvents makes it easy to prepare the recording sheet and to obtain a deep image on the paper.

4. The present fluoran compounds have no solubility and good stability in water, acids or alkalis. For example, 2-(5f,6',7',8'-tetrahydro-2'- naphthylmethyl)amino-8-diethylamino-benz[clfluoran can be boiled with an alkali solution without being destroycd.

5. The present fluoran compounds have good fast nesscs to light, moisture and sublimation.

The obtained deep image on this recording sheet does not disappear or change in color by moisture or droplets of water, or by exposure to sun-light or by .heating.

The recording sheet prepared with use of the present fluoran compound endures storage for a long period of time without the disappearance of the image on the documents and slips.

6. The present fluoran compounds have high colordeveloping speed. Such color formation occurs just at once when the fluoran compounds in the form of crystals or a solution in the above-cited solvents are brought into contact with the acidic electron-acceptor. Then, the recording sheet prepared with use of the present fluoran compounds gives vivid deep images on the paper at the moment when a pressure or impact is applied onto the paper by means of a pencil, a ballpoint pen or a typewriter.

7. The images on the recording sheet prepared with a mixture of the present fluoran compounds do not change in color owing to the same color-developing speeds caused by the same fluoran nucleus. The present fluoran compounds represented by the general formulas (I), (ll), (Ill) and (IV) may be prepared by the following methods.

In the presence of a dehydrating agent, fluorans (I), (II), (III) and (IV) can be prepared by reacting a o-(2'- hydroxyl-4'-aminobenzoyl)-benzoic acid represented by the formula,

m R N CO-Q COOH wherein R, and R signify R R,, R,., R,, R, and R,, Z and m are defined above, with a compound represented by the formulas R R R OR I! wherein R and R represent R R,,, R,, R,,, R and R,. E stands for benzene, naphthalene or tetrahydronaphthalene nucleus. R" indicates hydrogen atom, a lower alkyl group or an acyl group, and R R, and Y are as defined above, to obtain a fluoran represented by the following formulas,

9 R1 Y2 R O J /Rk 9 R wherein h RI! llh RIV! h h ks h Y1! Y2 M and E are as defined above.

The reaction may be effected at a temperatureof 0 to 300C for several hours or sometimes for a few days in the presence of a dehydrating-condensing agent. Examples of the dehydrating-condensing agent include sulfuric acid; phosphorous pentoxide; phosphoric acid; polyphosphoric acid; an hydrous metal halides such as anhydrous tin chloride or bromide, anhydrous zinc chloride or bromide, anhydrous aluminum chloride or bromide, anhydrous ferric chloride or bromide; phosphoric pentachloride or bromide; phosphorous trichloride or bromide; phosphorus oxychloride or oxybromide, and anhydrous hydrogen chloride or fluoride.

If necessary, carbon disulfide, chlorinated benzenes, or nitrobenzenes are used as a solvent for the reaction.

After. the reaction is over, the reaction mixture is poured into ice or'water to separate solid, and if desired, the mixture is neutralized with a solution of an alkali such as caustic soda, potassium hydroxide an the like.

in order to convert the resulting solid to the pure fluoran compound represented by the formula (I), (ll), (Ill) or (IV) by purification, the solid may be'dissolved and heated in a solvent and then the mixture may be cooled or concentratedto obtain the fluoran compound (I), (ll), (lll) or (IV) as white crystals.

As a solvent for the purification, aromatic hydrocar bon solvents such as benzene, xylene, etc.; nuclear halogenated aromatic hydrocarbon solvents such as chlorobenzcne,v bromobenzene, dichlorobenzenes, trichlorobenzenes, etc.; alcohols such as methanol, ethanol, etc.; amide solvents such as dimethylfonnamide,

halogenated aliphatic hydrocarbon solvents such as chloroform,bromoform, methylchloroform, etc.; and ethers such as dimethyl ether, diethyl ether, etc. are

useful. I i i a The purificationis often facilitated by the addition of an aliphatic aminesuch as dimethylamine, trimethylamine, diethylamine, triethylamine, etc.; an aliphatic aminoalcohol such as ethanolamine, propanolamine, ctc.; or a heterocyclic'basic'substance such as pyridine, picolinc. ctc. 1 i

White crystals, which separate on heating and then cooling in any one of these purification solvents or a mixture thereof, are filtered and washed with a'nonpolar solvent such as cyclohexane, nhexane, diethyl ether-to obtain a colorless compound. In case ofa com wherein R,,,, R Y Z, E. and m are as defined above, may be reacted with a m-aminophenol at a proper reaction temperaturein the presence of a dehydrating agent as explained above to obtain a fluoran compound.

The reaction preceeds as follows:

COOH

wherein R", R,, R R R Y., E, Z and m 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 fluoran compound prepared by the first or second methods. Thus, a aminofluoran represented by the formulas,

, amino s'ubstituent of the fluoran nucleus, is treated with (wherein R,, R Rm, Rh, Y E, Z and m are as defined above), which has at least one hydrogen atom in the an alkylating agent,'an acylating agentora sulfonylating agent as explained below in the presence or absence of a dehydrating agent or a dehydrohalogenating agent. The reaction is properly carried out at 0 200C for (wherein R,, R R,, R Y., Z, m and E are as defined several hours or sometimes for a few days, if desired, above, and X each signifys a residue of the alkylating, in the presence of a solvent such as benzene, toluene, 3o acylating or sulfonylating agent such as halogen atom, xylene, chloroform, l,2 dichloroethane, ether, dioxhydroxy group, 80,", POff', etc.)

ane, N,N-dimethylformamide, dimethylsulfoxide, alcoin the same way, a fluoran compound represented by hols, etc. the formula (ill) may be obtained by reacting fluoran The reaction proceeds as follows: compound represented by the formula,

N O 40 H/ W Rk U K R! gg co RIVX (wherein R., R,, R,,, R,, Y Z and m are as defined above), which has at least one hydrogen atom in the amino substituent, with an alkylating agent, an acylating agent or a sulfonylating agent as explained below.

Examples of the acylating. alkylating and sulfonylati. Acetic anhydride Propionic anhydride Butyric anhydride Propionic anhydride Crotonic anhydride ing agents which may be used in the above-mentioned reaction include:

Benzoic anhydride l 3-Phenyl-2-propynyl bromide m-Chlorobenzoic anhydride 8. Oxiranes m-Nitrobenzoic anhydride Ethyleneoxide p-Bromobenzoic anhydride m-Methylbenzoic anhy- Propyleneoxide dride Z-Ethyloxirane p-Methoxybenzoic anhydride l5 2.2-Dimethyloxirane 2. Acetyl chloride Propionyl chloride 2,3-Dimethyloxirane 2,2-Diethyl-3-methyloxirane Acryloyl chloride 2,2-Diphenyloxirane Methacryloyl chloride 2-(4'-Nitrophenyl)-oxirane Acetyl bromide 2-Phenyloxirane 2-(2'-Chlorophenyl)-oxirane Butyryl bromide t 9. Sulfonylating agents: Propiolyl bromide Methanesulfonyl chloride Crotonyl bromide Ethanesulfonyl chloride Benzoyl chloride Propanesulfonyl chloride m-Chlorobcnzoyl chloride Butanesulfonyl chloride p-Nitrobenzoyl chloride Benzenesulfonyl chloride m-Bromobenzoyl chloride p-Toluenesulfonyl chloride p-Methylbenzoyl chloride m-Toluenesulfonyl chloride m-Methoxybenzoyl chloride p-Chlorobenzenesulfonyl chloride Benzoyl bromide l o-Chlorobenzenesulfonyl chloride m-Nitrobenzenesulfohyl chloride o-Nitrobenzenesulfonyl chloride m-Methoxybenzenesulfonyl chloride and bromides thereof such as, for example,

Methanesulfonyl bromide Ethanesulfonyl bromide Benzenesulfonyl bromide p-Toluenesulfonyl bromide p-Chlorobenzenesulfonyl bromide p-Nitrobenzenesulfonyl bromide p-Methoxybenzenesulfonyl bromide 10. Miscellaneous p-Chlorobenzoyl bromide m-Nitrobenzoyl bromide m-Methylbenzoyl bromide -o-Methoxybenzoyl bromide- Also, as'the alkylating agent, the following compounds are preferable.

3. Esters: Dimethyl sulfate Diethyl sulfate Dipropyl sulfate Trimethyl phosphate Triethyl phosphate Methyl benzenesulfonate Methyl p-toluenesulfonate Propyl p-toluenesulfonate Methoxyethyl p-toluenesulfonate Methoxypropyl p-toluenesulfonate Methyl methanesulfonate Propylmethanesulfonate 4. Lower alkyl halides: Methyl chloride Ethyl bromide Propyl chloride c o 8 Butyl chloride 5. Benzyl halides: l 55 t 3 Benzyllchloride m-Nitrobenzyl chloride p-Chlorobenzyl chloride m-Bromobenzyl chloride 6O p-Methylbenzyl chloride m-Methoxybenzyl chloride Bcnzyl bromide C p-Nitrobcnzyl bromide l o-Bromobcnzyl bromide C1-C3 m-Methylbenzyl bromide o-Methoxybenzyl bromide 6. Allyl halides: C1Cl l2 Allyl chloride U men; s

CiCH B l0 CH3 Br I ClCH n:

chore-( 1 I t COCH;

no-cm gmcnym I Cl-CH QE m2 Q0 ClCHg -Q- ori -Q I l Compound Colour precursor 1 ci-cs; Q-o-G a CI-CH As the dehydrohalogenating agent,

Sodium hydrogencarbonatze Potassium hydrogencarbonate Sodium carbonate Potassium carbonate Sodium acetate Potassium acetate and Caustic soda may be used. Also if circumstances permit, the basic substance used in the purification, may be used.

As the solvent in the third method, aromatic hydrocarbon solvents such as benzene, xylene, etc.; halogenated aliphatic hydrocarbon solvents such as chloroform, bromoform, methylchloroform, etc.; halogenated aromatic hydrocarbon solvents such as chlorobenzene, bromobenzene, dichlorobenzenes, etc.; alcohol solvents such as methanol, ethanol, propanol, etc.', ether solvents such as diethyl ether, dimethylene glycol, dimethyl ether, diethylene glycol, etc.; sulfoxide solvents such as dimethyl sulfoxide, 'diethyl 'sulfoxide, etc.; and amide solvents such as N,N'-dimethylformamide, dimethylacetamide, N-methylpyrrolidone may be used.

Specific examples of the compounds of the general formulas (I), (ll), (Ill) and (lV) "produced by the above-mentioned methods according to the present invention which show excellent resistance to water, good fastness to light and rapid color developing speed are as follows. Shade on silica gel after development for eachcompound is also shown below.

Shade after development Dark green m.p. 242 244C Colour precursor 2 H3CH2)2N Q Red N CH g m )2 m.p. 98.6 0

Colour precursor 3 on (orgcugyw o 3 CH Green 0 (1:0 as m.p. 136 140% Colour precursor 4 Colour precursor 5 (C2H5)2N Dark green m.p. 190 195o Colour precursor 6 (CH3CH2)2N o D\ CH Dark green 0 3 60 org-@- 0@ mp. 126,3c

Colour precursor 7 (CH3CH2)2N O Greenish black 0 K H 6O GHQ-G0 m. p. 110.5%

Colour precursor 8 n e e r G Colour precursor 9 n e e r G m.p. 133 135C Colour precursor 1O n e e r G Colour precursor 11 C O 6 9 1 8 T- .04 5.0 11 l MD- Pm 2 Colour precursor 12 Red m.p. 167 168C Colour precursor 13 Dark green W 2 H C m.p. 196 198C 2 Colour precursor 14 C H N O 2 5 2 Greenish black 0 NHCHTHSH m.p. 144 145C I C0 Colour precursor l5 (CH3CH2)2N 0 Purplish black 0 NHCH 1 m.p. 213 2170 CO Colour precursor l6 Bluish green I m.p. 123 124o Colourrprecursor 1? (on on ocn Red c 2 2 32 co mp. 121.6C

Colour precursor 18 Green Colour preoursor 1g (CH3CH2)2N Green Colour precursor 20 (CH3CH2)2N O 0 N(CH2CH2OCH3)2 Green Colour precursor 21 Green Coloiuprecursor 23 (CH' CHQgN Dark green Colour precursor 24 Relddish purple imp. 219.390

op. ,m. 242.1%

n w m m b .n n. m

d w m m R Red Colour precursor 26 Colour precursor 27 Colour precursor 28 n on a u r r r G G .nuGUCHj Colour precursor 29 Colour. precursor '50 Colour precursor 31 2-( I '-Naphthylmedryluminn)-8-dimethyl-uminobenzlc lfluoran nrnyUurninn] Dark green Green Red Red

Red

Dark green Red I Red Dark green Red Red

Red

Green Green Dark green Blackish green Dark green Dark green Dark green Green Green Green Black-green Black-green Green Red Green Green Violet-red BIaek-green Black-green Greenlah black Greenish black Greenish black Green Berk-green Red Red

Green Red Green Red Red

-Continued diaflylaminobenzl clfluoran 2-[ 3'-( p-Methylphenyl )-propi0nyIamino]-8- Red bis(p-chlorobenzyl)aminobenzlclfluoran 2-( 2'-Pyridylmethyl )amino-B-l bis- Green (melhoxymethyl)amino]-4'-2'.4'-dimelhylbenzylideneaminobenzl clfluoran 2-l N-Ethyl-pyrrole-2'-carbonami-do]-8[ bis-(p- Red chlorobenzyl)amino]-4'-' dimethyluminobenzlclfluoran 2-(4'-Methoxy-2-ethoxy-phenylamino)-8-di(3'- Red furfuryhaminobenzlclfluornn 2-( 4'-Chlorobenzenesulfonylamino)-8-bis( S'- Red Greenish black Green Greenish black Greenish black 2-( 2'-Furoylumino )-6-bis-( melhdxymethyl- Red )aminofluoran 2-(u-Naphthylacetylamino )-6- Red dihenzylarninofluoran 2-l3'-(4"-ChIoro-2"-methyIphenyI)-2'- Green propynyl]amino-6-bis-(B-chlorocthyhamino- Violet-black 2-(p-Chl0roben7hydrylamino)-8- Dark green dielhylaminobcnzlclfluoran 2-(o,pDichloro-p'-methoxybenzhydrylamino)- Green 8-dimelhylamin0fluoran 2'(N.N-Bis-benzhydryl)amino-6- Red diethylaminofluoran 4 2-(N,N-Bis-benzhydryl)amino-8- Green 2-[ N-MethyH p-chlorobenzhydryhamino] Violet black Green -4-chloro-6-diethylaminofluoran diphenylelhyl)uminol-6-dimethylaminofluoran Green Red Red

Red

Violet-red Violet-red Green Black-green -Continued Black-green Black-green Green Green Green Black-green Red Green Black-green Black-green Green Red Red Red Green Green Red Red

Red

Black-green Green 7 Black-green -Continued benz! b1lhienylmethylaminol-8-din1ethylamino- 4'-methoxybenz!c lfluoran 4 e Pentachlorophenyl\hio)benzyl-2"- Dark green Black green Dark green Black-green Dark green Dark green Dark green Red Red

Red

Green Red Red

Red

Green Green Dark green Dark green Red Red

Green Green Green Green Red Red Red Red

-Cominued Z-Bia-(B-Methoxyethyl)umino-B-dibenzylumino- Green Green Green Green Red Red

Red

Green Red Green Green Green Reddish violet Black-green Green Red Red Black-green Black-green Green Green Red Black-green Green Red Violet-red Black-green Green Green Green Red Green Green Black-green Red r Green Red Green Red Red 'Red Red

Green Blu ck green -Continued Green Red Black-green Green Black-green Red Red

Red

Green Green Green Green Red Red

Red

Green Red Green Green Red Red

Green 7 Dark green Green Green Dark green Green Red Green Green Red Red

-Continued 2-[ N-( 2'-thenyl)-p-toluenesulfonylumino1-6-bis- Red (o-bromobenzyl )aminofluoran 2-(N-2'-Quinolylmethyl-propionylsmino)-6- Red bisl rn-( n-propylbenzyl )aminol-fluorsn 2-!a.a'-Diphenyl-phenethylamino]-6- Dark green methylaminofluoran 2-( l',l '-Diphenyl-n-butylsmino)4-n-buthoxy-6- Dark green di-n-propylaminot'luoran 2-lN,N-Bis(2'-quinolylmethyl)smino]-8-bis(p- Red isopropylbenzyl)aminobenzlclfluorsn 2-1 l-lsobutyl-l'-(a-nsphthyl)-n-propylamino]- Green S-bis-lo-(n-butoxy)benzyl]aminobenzlclfluoran 2-[4'-n-Butoxyearbonyl-Z'-thenylamino]-8- Green bl|(-ymethoxypropyl)aminobenzlclfluoran M N-( 3'-Benzo[ blthlenyl )smino1-6-bis(7- Black-green hydroxy-n-propyl)sminofluorsn 2-(2'-Furhrrylamino)-4-n-butoxy-6- Black-green diethylsminofluoran 2-(N,N'-Di-2-thenylsmino)-4-methoxy 6- Dark green diethylaminofluoran i 2-[N,N-bis-( 2'-pyrrolylmethyl )arnlno-6- Green diethylaminotluoran 1 2-[ 2'-Benzyl-4-methyl )cyclohexylaminol-S- Green diethylaminobenzlcmuoran 2-l2'-(p-Methoxybenzyl)cyclohexylamino|-8- Green diethyluminobenzlclfluoran 2-l 2'-(p-Chlorobenzyl )cyclohexylaminol-S- Green diethylaminobenzlclfluoran 2-(2,6'-Dibenzylcyclohexylamino)-6- Green diethylaminofluoran 2-(2-Phenethylcyclohexylamino) 6- Green diethylaminofluorun 2-! 2'-( 'y-Phenylpropyl )cyclohexyiaminol-(r. Green diethylaminolluoran 2-(2',6'-Diethylcyclohexylamino)-8- Green dibenz laminohenzlclfluoran 2-l 2'- ethyl-6'-benzyl )cyclohexylamino1-8- Green dibenzylaminobenzlclfluoran 2-( l -Phcnethylethylamino)-8- Green diethylaminobenzlclfluoran 2-(l' Green -Phenethylpropylamino)-8- diethylaminobenzlclfluoran 2-ll'-(p-Chloropheneth l)-2'- Green mcthylpropylarninol-6 ibenzylarninofluoran 2-( l '-Phenethyl-Z'-methyl-propylamino)-8- Green dimethylaminobenzlclfluoran 2-[ l'-(p-Methoxyphenethyl)pentylaminol-6- Green dimethylaminofluoran 2-1 I '-Phenethyli'-methyl-butylamino]-8- Green diethylaminobenzlclfluoran 2-( I '-(a-Methyl-p-methylphenethyl Green propylamino l-b-diethylaminofluoran 2-[ I '-(a-Methylphenethyl)butylaminol-b- Green dihenzylaminolluoran 2-[ l '-(a-Methylphenethyl )-2'- Green rnethylpropylaminol-8- dimethylaminobenzlclfluoran 2-[ l '-(a-Ethylphenethyl )butylamino 1- Green diethylaminobenzlclfluoran cording system utilizing an electron donor-acceptor color-forming reaction between chromogenic material and acidic material. V

The pressure-sensitive recording systems generally comprise color-forming compounds on and/or withinone or more sheet supports, the color-forming compo-.

nents being isolated from one another by a pressurerupturable barrierqwhere the color-forming compo nents are disposed on separate sheets as disclosed in U.S. Pat. No. 2,712,507, the record material referred to as a "transfer" or "couplet" system. in such system, a solution of a chromogenic material is held in rupturable microscopic capsules coated onto one surface of a transfer sheet, while an adjacent receiving sheet is sensitized with an acidic material. i.e., an electron acceptor. Most common acidic materials are activated acid clay and acid clays, such as attapulgite, zeolite, bentonite, kaolin and silica. Recently, monomeric phenols or acid reactant polymeric materials, such as phenolic polymers, phenol acetylene polymers, maleic acid-rosin resins. have been suggested either alone or in combination with acid clays.

in the manufacturing method of such record material, for instance, a non-volatile oil containing a chromogenic material dissolved therein is protected by encapsulation with coacerva'te film of a water-soluble polymer. The resulting coating composition containing dispersed capsules are coated on one side of a sheet, and coating composition of said electron acceptors is coated on the other side of the sheet. When several sheets are laid one over another and impressed with a pencil or the like. Capsules are collapsed torelease the oil containing chromogenic material which produces a duplicated image on contact with v the electronacceptor. In another system as disclosed in U.S. Pat. No. 2,730,457, a coating liquid containing both of the capsules chromogenic material and acidic material is applied on one side of a sheet or alternatively, a coating containing capsules is first applied on one side of a sheet and the second coating containing the electronacceptor is applied thereon. Thus, all the components are disposed on a single sheet, the record material is referred to as self contained" system and develops image color where the pressure is applied.

As a modification of pressure-sensitive marking sys tem, Japanese Pat. No. 511,757 (corresponds to U.S. Pat. application Ser. No. 392,404,tiled on Aug. 27, 1964) discloses a recording; sheet, in which minute capsules containing liquid solvent are coated on one surface of a sheet support and both of the chromogenic material and the acidic polymer are coated on or impregnated in same sheet or other sheet in solid condition.

There is thermo-responsive record sheet as a markforming system utilizing an electron donor-acceptor color-forming reaction. For example, Japanese Pat. Pub. No. l4039/ 1970 (corresponds to U.S. Pat. application Ser. No. 554,565 filed on June 1, 1966) discloses a temperature-responsive recordmaterial comprising a supporting sheet material having crystal violet lactone and a phenolic material solid at room temperature but capableof liquefying and/or vaporizing at normal thermographic temperatures, said lactone and phenolic material being further capable of producing a mark-forming reaction upon reactive contact.

The novel compounds of our invention are widely usedfor above-mentioned. mark-forming system as a colorless chromogenic compound, i.e., electron donor,

EXAMPLEJ (COLOUR PRECURSOR NO. 24)

140 Grams'of 95 %-sulfuric acid-was eharged'into a four-necked flask. A mixture of 26.5 g of 2-hy'droxy-5- amino-diphenyl hydrochloride and 31:3-g of "o-(-2'- hydroxy-4 -diethylaminobenzyl) benzoic acid was added for one hour below 25C: At that time, the'hydrogen chloride gas evolved was absorbed in a absorber. After dissolution, the mixture was warm ed to 25 to 30C for 8 hours. After cooling, the reaction mixture was then poured into 1.5 kg of ice-water at 10 'to C.-The mixture was neutralized with an aqueous caustic soda solution at the'same temperature.

The precipitate was filtered and washed with water. The thus obtained crude solid, 2-amino-4-phenyl-6- dietjnylaminofluoran was dissolvedin 500 g of benzene and 'dehydrated with 50 g of anhydrous sodium sulfate. After addition of 5 g of active charcoal, the benzenesolution was filtered while hot. The filtrate was concentrated under reduced pressure to obtain the syrups.

Thus, 2-amino-4-phenyl-6-diethylaminofluoran was obtained as white crystals. After recrystallization from benzene the compound Ihad m.p. of-2l9.-3C.

The resulting compound, formed dark reddish brown color on contacting with silica gel when used as a material for pressure-sensitivecopying paper. The'image having excellent fastnesses to moisture, sublimation and alkali was produced.

EXAMPLE 2 (coLouR PRECURSOR No, 8)

By. use of the same procedure as in Examp1e:1,'2-( 1- pyrr'olidinyl)-6-diethylaminofluoran was prepared from N-(4-hydroxyphenyl)-pyrro1idine and 2-(2'-hydroxy- 4-diethylaminobenzoyl)-benzoic acid. Yield: 41.8 Meltingpoint: 238 240C. This compound formed dark'green color on silica gel withgood fastnesses to light and moisture.

EXAMPLE 3 (COLOUR PRECURSOR NO. l7)

According to the same method as in Example -1, 2- [N,N-bis-(B-methoxyeth'yl)aminol-8- sol,

36 diethylaminobenzlclfluoran was prepared from N,N- bis-(B-methoxyethyll-4-amino l naphthol and 2-(2'- hydroxy-4EdiethylaminobenzoylJ-benzoic acid. This derivative having a melting point'of l95.3 to 196.3C formed dark green color on silica gel.'

EXAMPLE 4 (COLOUR PRECURSOR No. 22

On cooling with, water-in 3 00 cc flask, 25.3 g of 4-cyclohexylamino-l naphthol was dissolved in 150 g of sulfuric acid below 20C. Then at the same temperaturc, 3l.3 g of 2-(4' diethylamino-Z'-hydroxybcnzoyl)-benzoic acid was added. After completion of the dissolution, the reaction mixture :was stirredfor 15 hours between 20C and 30C. After the reaction was over, the reaction content .was poured into 1.5 kg of ice-water mixture at about 0C. After neutralized and set the pH to ll with sodiurn'hydroxide solution, the obtained crude solid was filtered, the solid was recrystallized repeatedly 26 g of 2 -cyclohexylami'no-8-diethylamino-benz[c]fluoran was obtained as white crystals having a'melting point of 272.2C. This compound formed dark green color on silica gel anddid not change in color during storage for a long period of time.

EXAMPLE 5 (COLOUR PRECURSOR N0. 23)

In the same way colour precursor No. 23,, 2- cyclohexylamino--diethylaminofiuoran was obtained from N-cyclohexyl-p-anisidine and 2-(4'-diethylamino 2'-hydroxybenzoyl)-benzoic acid. This compound formed greenish black colour on silica gel andhad a good fastness to light and moisture. m.p.: 212.2- 213.2C

EXAMPLE 6 (COLOUR PRECURSOR NO. 27)

Colour precursor No. 27, 2-amino-8-diethylamino- 3,4,5,6-tetrahydro-benz[c]fiuoran was prepared with 4-amino5,6 ,7,8-tetrahydro-l naphthol and 2 -(4'- diethylamino-Z'-hydroxybenzoyl)-benzoic acid. This compound, having a melting point'of242. 1C gave reddish brown colour on silica gel.

EXAMPLE 7 (COLOUR PRECURSOR NO. 20)

2-[N,N-bis-lB-methoxyethyll aminolodiethylaminofluoran prepared from N,N-bis-(B- "methoxyethyl)-p-anisidine was obtained as white crystals, mp; 953C. This derivative gave dark green colour on silica gel and good light fastness.

i EXAMPLE 8 1n the same manner as in Example 1, the following compounds were synthesized. Shade on silica gel is shown on the right hand column.

Bunauy tbenzotc aetd Amtnophencl Colour Grunt" cmmtGcoQno bun HO O M -U11. Br

Claims

1. A COMPOUND OF THE FORMULA

2. 2-(2''-Benzylcyclohexylamino)-8-diethylaminobenz(c)fluoran.

3. 2-Cyclohexylamino-8-diethylaminobenz(c)fluoran.