DE2202315A1 - Fluorane derivatives - Google Patents

Description

48 326

Applicant: YAMAMOTO KAGAKU GOSEI KAEUSHIKI KAISHA, 182-1 Yuge, Yao-shi, Osaka / Japan

Fluorane derivatives

The invention relates to fluorans having a .lonophenylamino group and their core substitution derivatives, as well as a new process for their preparation. These Fluorans and fluoran derivatives are highly effective color formers for pressure-sensitive copier papers

Basically, pressure-sensitive copier paper is made of two sheets of paper. The lower surface of the upper sheet is coated with tiny capsules that are color-reactive achromatic substance (hereinafter referred to as "color former") as a solution in a poorly volatile solvent, while the upper surface of the lower sheet is coated with a solid acid, such as acid clay, phenolic compounds and the same. When the lower surface of the upper sheet and the upper surface of the lower sheet are placed against each other and pressure is applied to the upper surface of the upper sheet by hand or machine writing will, bo tear the capsules under the action of pressure and the color former contained therein is through the solid acid on the top surface of the bottom sheet absorbs and develops a color, creating a copy will.

There is also a type of pressure sensitive copier paper showing a mechanism of developing color when local pressure is applied to a sheet of paper,

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the capsules containing a color former and a solid acid on or in the paper sheet. This guy is however, in terms of the mechanism of color formation, very similar to the first mentioned pressure-sensitive copier paper, which consists of two sheets of paper, an upper and a lower sheet. It. can therefore be the same for both types Color formers are used.

Various types of chemical compounds have been used as color formers. Among other things have fluoran compounds has recently gained great importance in the field of pressure-sensitive copier papers because of these compounds develop a rich variety of colors and exhibit high color development speeds.

For example, 3> 6-dimethoxyfluorane (Beilstein Hauptwerk, Volume XIX, page 225) slightly yellow Parbe, 7-chloro-6-methyl-3-diethylaminofluoran (published Japanese patent application 21 199/1968) turns slightly yellowish red, Rhodamine lactone (Beilstein Hauptwerk, Volume XIX, page 344) changes to bluish red and 3-diethylamino-7-methylaminofluoran (Canadian patent 814 948) changes to a greenish-blackish green.

Many of the derivatives and homologues mentioned are commercially available as dyes for pressure-sensitive copier paper.

There has now been a new process for the production of fluorane compounds, containing a monophenylamino group or their core substitution derivatives of the following general ones Formula I found (this compound is hereinafter referred to as "monophenylaminofluoran compound").

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h a

(D

In this formula, each of the radicals R- and 'R ₂ denotes a methyl or ethyl group, each of the radicals R ^ and R denotes a hydrogen atom, a methyl or ethyl group, R ^ a hydrogen atom or a lower alkyl group and η is an integer from 1 to 5, where R, and R are not simultaneously hydrogen atoms.

Develop as a color former for pressure-sensitive copier paper the new fluoran compounds green or black in color. They show exceptionally good properties in terms of important requirements of color development speed, the density of color developed, light resistance after color development and solubility. To manufacture the new, pressure-sensitive copier paper, the compounds are dissolved in a non-volatile solvent and enclosed in tiny capsules that are used in conjunction with a solid acid.

If monophenylaminofluorane compounds (I) are to be produced in practice by a conventional method, The high manufacturing cost is a problem caused by the low yield and the difficulty of separation the reaction by-products are conditional. The improvement of manufacturing in this regard is a very important problem.

When it is attempted to prepare the compounds (I) by the conventional method, the procedure follows the following formula scheme:

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Therein R ₁ , R _{2 , R 1} , R-, R 1 - and η have the meaning given for formula I, while X .. stands for a halogen atom or a hydroxyl group ο

The above reaction can never be applied to industrial Manufacture are used because the ring cleavage of the lactone ring, the decomposition of the puoran core and other factors reduce the yield.

The synthesis method shown below is also contemplated.

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. 4-

COOH

'EUSO

R * and R ₅ - those given in formula I.

In it, R-, R

Meaning 'and X- stands for a hydroxyl group or a halogen atom and Rg for a hydrogen atom or a lower alkyl group «,

In this case it is necessary to obtain the intermediate (II) in its synthesis in extremely high purity in satisfactory yields. If the obtained intermediate (II) is not pure, it also leads to a decrease in the purity of the compound (I) and a change in the hue of the developed color when this compound is printed on the pressure-sensitive copying paper

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is applied, thereby causing various disadvantages in terms of practical use.
However, the conventional method represented by the above formula also generates such an amount of impurities as by-products that it is not possible to produce the
to obtain desired product at a reasonable cost in view of industrial production in high purity.

It is an object of the invention to produce the compounds (I) with a low process complexity and low cost in a high quality which is sufficient for use for pressure-sensitive copying paper.

It has been found that the compounds (I) can be obtained in high quality in satisfactory yields and at a low cost can be obtained by the method described below.

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OR '

(V)

cone. K ₂ SO ₄

In this formula scheme, R ^, R ₂ , R ,, R ,, Rc and η have the meaning given for formula (I), while each of the radicals R and Ry represents a lower alkyl group and X means a halogen atom »

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As can be seen from the formula of the compound (III), this compound (III) can be converted into the compound (V) when, for example, an aliphatic acyl group has been previously introduced into an amino group. In this case, the compound (V) in high quality and in high yields, obtained as about 80% _t simply by the first-mentioned compound with the aromatic halogen compound (IV) is refluxed under ordinary pressure. The obtained compound (V) is also converted to the high quality compound (VI) in high yields such as more than 80% when it is heated in an alkaline aqueous solution. It is very important to introduce an alkyl group R into the compound (III) in order to obtain the compound (VI) in satisfactory yields and by simple procedures through the deacylation reaction (i.e., the synthesis of the compound (VI)). The intermediate (VI), which is not only obtained in good quality and at a low cost, but is also well suited for the preparation of the compound (I) which can be applied very cheaply to pressure-sensitive copying paper, can easily be obtained because aliphatic acyl and alkyl groups have been introduced into the compound (III).

The invention therefore relates to new fluorane compounds of the formula I already given.

The subject matter of the invention is also a process for the preparation of these compounds of the formula I, which is characterized in that is that an acylaminophenol of the formula III given above with an aromatic halogen compound of the specified formulas IV and VI *, the reaction product of the formula V to the diphenylamine derivative of the formula VI deacylated and the compound VI with ortho- (4-dialkylamino-2-hydroxybenzoyl) benzoic acid condensed.

The invention also relates to a pressure-sensitive copier paper, to which at least one fluoran derivative of the formula I is applied. - 9 -

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In one embodiment, this is pressure sensitive Copy paper made from two sheets of paper, with the fluoran derivative in capsules that are placed on the underside of the are applied to the top sheet of pressure-sensitive copier paper. The top of the bottom sheet of this copy paper contains a solid acid.

According to another embodiment, this is pressure-sensitive Copy paper from a single sheet of paper, which contains the fluorane derivatives in the form of a solution in tiny capsules, and which also has a solid acid.

According to a specific embodiment of the invention means the radical R, a methyl or ethyl group, while the other radicals have the meaning given. Another embodiment are compounds in which Ej stands for an ethyl group and the other radicals in the formula I have the meaning already mentioned. According to a further embodiment, Rj- means one of Methyl Various lower alkyl groups, such as an ethyl or propyl group.

The invention is illustrated by the examples below.

example 1

Preparation of 3-diethylamino-6-methyl-7-anilinofluoran (VIII).

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C ₂ H ₅ X

(VII)

OCH ₃

(VIII)

OCH ₃

(DO

24 g of 3-methoxy-6-acetylaminotoluene (VIII, Beilstein, first supplement to Volume 13, page 223), 31.6 g of bromobenzene, 10.38 g of potassium carbonate, 0.6 g of copper powder and 0.01 g of iodine were refluxed under normal pressure on the oil bath for 48 hours. Excess bromobenzene was then obtained by steam distillation and the remaining reaction equipment was distilled in vacuo, giving 29.2 g (85.0 % of the theoretical yield) of 3-methoxy-6- (N-acetylanilino) toluene (IX) as a pale yellowish-brown pesticide with a melting point from 86 to 87 ° C.

Then 25 g of the compound IX were submitted and hydrolyzed by heating at 180 ° C. for 8 hours in an autoclave with 130 ml of water and 9 g of sodium hydroxide. After cooling, the reaction product was filtered to give a solid which was recrystallized in twice the amount of ethyl alcohol. 18.8 g (90.5 ¥> the theoretical yield) of 3-methoxy-6-anili: iotoluene were obtained in the form of light brown crystals with a melting point of 79 to 80.5 ° G.

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10 g of the 3-methoxy-6-anilinotoluene obtained and 14.7 g of ortho- (4-diethylamino-2-hydroxybenzoyl) benzoic acid were mixed into 50 ml of concentrated sulfuric acid and 42
Stirred at 25 ° C. for hours. The mixture was then poured into 50 ml of water and the precipitate was filtered off, washed with 300 ml of a 2% strength aqueous solution of sodium hydroxide solution at 60 ° C., dried and recrystallized from 220 ml of toluene. 14.2 g (63.5% of the theoretical yield) of 3-diethylamino-6-methyl-7-anilinofluoran (VII) were obtained in the form of white crystals with a melting point of 199.5 to 201 ° C.

Results of the analysis: G H IT

Theoretical \ 7ert 78.15 $ 5.88% 5.88% Found value 78.14% 5.68% 5.65%

Example 2

Preparation of 3-dimethylamino ~ 6-methyl-7-anilinofluoran (X).

CH _S \

¹ ^ (χ)

4.26 g of 3-methoxy-6-anilinotoluene, which is obtained by the method of Example 1 was obtained, and 5 x 7 g of ortho- (4-dimethylamino-2-hydroxybenzoyl) benzoic acid were ifi 30 ml more concentrated

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Sulfuric acid mixed and stirred at 15 to 25 C for 70 hours. The mixture obtained was poured into 200 ml of water and adjusted to a pH of 10 with sodium hydroxide solution. The precipitate obtained was filtered off and micrystallized from 200 ml of toluene. This gave 5.55 g (62 % of the theoretical yield) of 3-dimethylamino-6-methyl-7-anilinofluoran (X) in the form of light yellow crystals with a melting point of 201 to 201.5

Analysis results

Theoretical value Found value

C received H • 6th N C. .3 6th .25% 77 .6% 5. , 2 6% .19% 77 Λ1 * 5 < Ί%

Example 3

Preparation of 3-diethylamino-6-methyl-7 - (4'-methylanilino) -fluorane (Xl)

OCH,

NH

(XI)

21.8 g of I-methoxy-ö-acetylaminotoluene (VIII, see Example 1), 25 g of para-bromotoluene, 9.5 g of potassium carbonate, 1 g of copper powder and Oo01 β iodine were 40% under normal pressure

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Hours refluxed. The excess para-brointoluene was obtained by steam distillation and the remaining solid (crude 3-methoxy-6- (N-acetyl-4'-methylanilino) toluene) was filtered off and mixed with 100 ml of a 10% aqueous solution of sodium hydroxide solution without purification and then heated to 200 ° C in the autoclave for 8 hours. After cooling, an oil layer was removed and passed through Purified distillation under reduced pressure. 19 g (68.7 0 of the theoretical yield, based on VIII) 3-methoxy-6- (4'-methylanilino) toluene (XII) as yellowish brown, oily substance with a boiling point of 180 to 190 ° C / 5 mmHg is obtained.

Analysis results

Theoretical value Found value

10 g of the product XII thus obtained and 13.8 g of ortho- (4-diethylamino-2-hydroxybenzoyl) benzoic acid were in 50 ml • concentrated sulfuric acid for 18 hours at room temperature touched. The product obtained was treated in the same way as in Example 2, with 8.6 g (39.9 0 of the theoretical Yield) 3-diethylamino-6-methyl-7- (4'-methylanilino jfluorane (XI) were obtained in the form of light yellow crystals with a melting point of 201 to 202 ° C.

Analysis results. ·

C. 7th H 6th N 79 .300 7th .490 6th .170 79 .080 .500 .010

78 C. 6th H_ 5o N_ Theoretical value 77 .340 6o 160 5o 710 Found value example ο 260 13% 510 4th

Preparation of 3-diethylamino-6-methyl-7- (2 ^t , 4'-dimethylanilino) fluoran (XIII).

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C ₂ H _5x

OCH ₃

NH

CH,

CH ₃

(XIII)

CH ₃ (XIV)

80 g of 3-methoxy-6-acetylaminotoluene (VIII, see Example 1), 160 g of 4-bromometaxylene, 35 g of potassium carbonate, 2 g of copper powder and Oo2 g of iodine were refluxed for 48 hours at normal pressure on the oil bath. Excess 4-bromometaxylene was then obtained by steam distillation and the remaining solid (crude 3-methoxy-6- (N-acetyl-2 ', 4'-dimethylanilino) toluene) was filtered off and, without purification, with 300 ml of a 10 % aqueous solution Solution of sodium hydroxide mixed and heated in an autoclave to 200 C for 8 hours. After cooling, an oil layer was separated and purified by distillation under reduced pressure. This gave 22.8 g (78.7 % of the theoretical yield, based on VIII) of 3-methoxy-6- (2 ', 4'-dimethylanilino) toluene (XIV) in the form of pale yellow crystals with a melting point of 78 to 79 ° C.

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10 g of the compound (XIV) thus obtained and 13 g of ortho- (4-methylamino-2-hydroxybenzoyl) benzoic acid were stirred for 42 hours at ambient temperature in 92 g of concentrated sulfuric acid. The resulting mixture was treated in the same way as in Example 2, with 15.2 g (72.7 % of the theoretical yield) 3-Mäthylamino-6-methyl-7- (2 ', 4'-dimethy1-anilino) fluorane (XIII) in the form of light yellow crystals with a melting point of 108 to 110 G were obtained.

Analysis results

! Theoretical value Found value

78.

H
6,357 "

6 .:

JL 9.53% 9.42%

Example 5
Preparation of 3-diethylamino-6-ethyl-7-anilinofluoran (XV).

OCH,

OCH,

(XVI)

(XVlI)

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19o3 g of 3-methoxy-6-acetylaminoethylbenzene (XVI), 22 g of bromobenzene, 7.78 g of potassium carbonate, 0.43 g of copper powder and 0.01 g of iodine were refluxed on an oil bath under normal pressure for 48 hours. Excess bromobenzene was then obtained by steam distillation and the remaining solid (crude 3-methoxy-6- (N-acetylanilino) ethylbenzene) was filtered off and mixed without purification with 140 ml of a 10% aqueous solution of sodium hydroxide and left in the autoclave for 8 hours 200 C heated. After cooling, an oil layer was separated and purified by distillation under reduced pressure. 1408 g (66.0 % of the theoretical yield, based on XVI) of 3-methoxy-6-anilinoethylbenzene (XVII) were obtained in the form of a pale yellow oily substance with a boiling point of 185 to 215 ° C./13 mm Hg

10 g of the compound (XVII) thus prepared and 16.8 g of ortho- (4-diethylamino-2-hydroxybenzoyl) benzoic acid were stirred in 50 ml of concentrated sulfuric acid for 48 hours at ordinary temperature. The mixture obtained was worked up in the same way as in Example 2, with 12 g (55o2 % of the theoretical yield) of 3-diethylamino-6-ethyl-7-anilinofluoran (XV) in the form of light red crystals with a melting point of 103-105 ° C.

Analysis results

example 78 6th C_ 6th H 5 JL Theoretical value 78 .4% 6th 5 .72 * Found value .256 .01% «61%

Preparation of 3-diethylamino-5-methyl-7-anilinofluoran (XVIII).

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C ₂ H _5n /

(XVIII)

OCH

OCH,

(XX)

18 g of 5-acetylamino-2-methoxytoluene (XIX, Beilstein, First Supplement to Volume 13, page 217), 30 g of bromobenzene, 8.5 g of potassium carbonate, O ₀ 5 g of copper powder and 0.05g of iodine were gerüokflußt under atmospheric pressure 43 hours in the oil bath . Excess bromobenzene was then obtained by steam distillation and the remaining solid (crude 2-methoxy-5- (N-acetylanilino) toluene) was filtered off and, without purification, mixed with 100 ml of a 10% aqueous solution of sodium hydroxide and the mixture in autoclave 18 Heated to 180 ° C. for hours. After cooling, the pesticide was filtered off and purified by vacuum distillation. This gave 10.6 g (65.0% of the theoretical yield, based on XIX, of 2-methoxy-5-anilinotoluene (XX).

Analysis results

Theoretical value Found value

C. 7th H 6 " N 87% 7th .04% 6o 57% eofo • 11% 52%

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6.8 g of the compound XX thus obtained and 10 g of ortho- (4-diethylamino-2-hydroxybenzoyl) benzoic acid were stirred for 48 hours at room temperature in 50 ml of concentrated sulfuric acid. The mixture obtained was then worked up in the same way as in Example 2, 3.7 g (24.3% of the theoretical Yield) 3-diethylamino-5-methyl-7-anilinofluoran (XVIII) in the form of light brown crystals with a melting point from 124 to 126 ° C.

Analysis results

78. C_ 5 H 5 N Theoretical value • 77. 15% 6th .88% 5 .88% Found value Example 7 31% .12% .67%

A pressure-sensitive copier paper that acts as a color former 3-diethylamino-6-methyl-7- (4'-methylanilino) fluoran (the in Example 3) was prepared in the following manner:

60 g of gelatin and 60 g of gum arabic were dissolved in 50 ml of water at 40.degree. Separately, 6 g of 3-diethylamino-6-methyl-7- (4'-methylanilino) fluoran was dissolved in 120 g of diphenyl chloride. Then this solution was added to the aqueous solution of gelatin and gum arabic and completely dispersed and emulsified with the aid of a homogeneous mixer (homo-mixer). To this dispersion, water at 50 ° C. was added to increase the volume of the dispersion to 2000 ml. Then 90 ml of 10% acetic acid and water of 50 G were added with constant stirring until the weight of the total mixture was increased to 4 kg. After 1 hour stirring the dispersion was cooled with stirring with ice-water to less than 10 ⁰ G, and it was 10% sodium hydroxide solution added to adjust the pH to. 9 Then the dispersion was gradually brought back to room temperature. It was applied to the lower surface of a top sheet and dried.

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Separately, a solid acid such as acid clay and phenol compounds was applied to the upper surface of the lower sheet applied

When copying was carried out with a pressure-sensitive copying paper composed of the upper and lower parts thus prepared When the lower sheet passed, a black print excellent in light resistance was immediately developed

Example 8

A pressure-sensitive copier paper was used of the color former obtained in Example 6 prepared in the following way:

By dissolving 4 g of 3-diethylamino-5-methyl-7-anilinofluoran and 1.5 g of 3-diethylamino-7,8-benzofluorane (Beilstein Hauptwerk, Volume 19, page 351) in 120 g of diphenyl chloride and carrying out the process steps described in Example 7, a obtained pressure-sensitive copier paper. If local pressure was applied to the coated paper, it quickly developed a black print with excellent light resistance.

Example 9

A pressure-sensitive copier paper was made using the Color former obtained in Example 5 prepared in the following manner:

By dissolving 4 g of 3-diethylamino-6-ethyl-7-anilinofluoroan in 120 g of diphenyl chloride and treating the resulting solution in the manner described in Example 7, an aqueous solution containing dispersed minute capsules was obtained. It was dried to a dust from tiny capsules by spraying, which were then placed in a 4 # xylene solution of a p-phenylphenol-formaldehyde condensation product mixed in and dispersed. This dispersion in a solution was

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applied to a sheet of paper and dried to prepare a pressure-sensitive copying paper. If more local When pressure was applied to the coated paper, it quickly developed a black image with excellent Lightfastness.

Example 10

A pressure-sensitive copier paper was used of the color former obtained in Example 4 in the following way:

By dissolving 6 g of 3-diethylamino-6-methyl-7- (2 ·, 4 ¹ -dimethylanilino) fluorane in 120 g of diphenyl chloride and treating the resulting solution in the manner described in Example 7, an aqueous solution was obtained which dispersed, contained tiny capsules. This dispersion was mixed and dispersed with 8 g of a finely divided dust of p-phenylphenol-formaldehyde condensation product and also mixed with 40 g of pulp. After diluting with water until the final pesticide content was reduced to 0.5%, the mixture was passed through the screen of a Fourdrinier machine to form a sheet of pressure-sensitive copier paper. When local pressure was applied to the sheet obtained, it immediately developed a black print with excellent light resistance.

Example 11

A pressure sensitive copier paper containing 3-diethylamino-5-methyl-7-anilinofluoran, which had been obtained according to Example 6, contained as a color former, was in the following V / alternately manufactured:

60 g of gelatin and 60 g of gum arabic were in 50 ml V / ater of 40 ° C dissolved. Separately, there was 4 g of 3-diethylanuno-5-methyl-7-anilinofluoran and 1.5 g of 3-diethylarnino-7,8-bonsofluoran (Beilstein Hauptwerk, Volume 19 »

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Page 351) dissolved in 120 g of diphenyl chloride. Then this solution became the aqueous solution of gelatin and gum arabic added and completely dispersed and emulsified with the help of a homogeneous mixer. Water became this dispersion of 50 ° C given in order to adjust the volume of the dispersion to 2000 ml. Then 90 ml of 10? 5 strength acetic acid and water were added of 50 ° G was added with constant stirring until the weight of the total amount was increased to 4 kg. After stirring for 1 hour the dispersion was cooled to less than 10 ° C. with the aid of ice water with stirring and 10% sodium hydroxide solution was added added to adjust the pH to 9. It was then gradually brought back to room temperature. The mixture was applied to the lower surface of the top sheet and dried.

Separately, a solid acid, such as sour clay or a phenolic compound, was applied to the upper surface of the lower Applied to the leaf.

When copying with the pressure sensitive copy paper consisting of the upper and lower sheets thus prepared, it immediately developed a black one Imprint with excellent lightfastness.

Example 12

A pressure sensitive copier paper that contains the same color former as previously contained, was made in another way as follows:

By dissolving 4 g of 3-diethylamino-5-methyl-7-anilinofluoran in 120 g of diphenyl chloride and treating the resulting solution in the manner described in Example 7 prepared an aqueous solution containing tiny dispersed capsules. She became one through spray drying Dust is dried from tiny capsules, which are then dissolved in a 4% xylene solution of a p-phenylphenol-formaldehyde

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Condensation product were mixed and dispersed. This dispersion solution was applied to a sheet of paper and dried to prepare a pressure-sensitive copying paper. When local pressure on the coated Paper was applied, it immediately developed a green print with excellent lightfastness.

Example 13

A pressure sensitive copier paper that contains the same color former as previously contained, was made in another way as follows:

By dissolving 4 g of 3-diethylamino-5-methyl-7-anilinofluoran in 120 g of diphenyl chloride and treating the obtained Solution In the same manner as in Example 7, an aqueous solution containing dispersed minute capsules was obtained. This solution was mixed with 5 g of a finely divided dust mixed from p-phenylphenol-formaldehyde condensation product and a dispersion prepared and then mixed with 40 g of pulp. After diluting with water until the final pesticide content was reduced to 0.5% the mass passed over the screen of a Fourdrinier machine to form a sheet of pressure sensitive copier paper. When local pressure was applied to this sheet, it quickly developed a green print with excellent Lightfastness.

In Examples 7, 8, 9 and 10, diphenyl chloride is used as the low-volatility solvent. Essentially the same results are obtained when no low volatility solvent is used instead of diphenyl chloride a lower-alkyl-substituted diphenyl is used, such as methyl, ethyl, or propyldiphenyl, or a higher alkylbenzene, such as dodecyl, decyl or octylbenzene, with a Boiling point greater than 150 ° C. If the boiling point of the solvent is at least 150 ° C, it is for the Sufficiently volatile for purposes of the invention.

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The solid acid acts as an electron accepting adsorbent * Instead of the solid acids used in the preceding examples, zeolites, bentonite, attapulgite can also be used or Silton (product of Mizusawa Kagaku Kogyo K.K.) can be used with excellent results.

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Claims (1)

- 24 claims in which each of the radicals R and R _{2 is} a methyl or ethyl group, each of the radicals R and R is a hydrogen atom, a methyl or ethyl group, Rc is a lower alkyl group or a hydrogen atom and η is an integer from 1 to, where R, and R. do not simultaneously represent hydrogen atoms. 2ο pluorane derivatives according to claim 1, characterized in that that R-z denotes a methyl or ethyl group. 5. Pluorane derivatives according to claim 1 or 2, characterized in that R- is an ethyl group. 4. Pluurane derivatives according to claims 1 to 3 »characterized in that that Rc represents a lower alkyl group other than methyl. 5. 3-Dimethylamino-6-methyl-7-anilinofluoran. 209832/1 222 6 «3-diethylaclino-6- ■ methyl-7- (4'-methylanilino) fluoran. 7. 3-Diethylamino-6-methyl-7- (2 ^l , 4'-dimethylanilino) fluoran. 8. 3-Diethylamino ~ 6-ethyl-7-anilinofluoran. 9ο 3 ~ diethylamino-5-methyl-7-anilinofluoran. 10. Process for the preparation of fluoran derivatives according to An ■ Proverbs 1 to 9, characterized in that an acylaminophenol of the general formula III with a halophenol of the formula IV converts the obtained, - N-acylated diphenylamine derivative deacylated to the diphenylamine derivative (VI) VI and this diphonylaniine derivative (VI) with ortho- (4-bialkylamino-2-hydroxybenzoyl) benzoic acid condensed, - 26th 209832/1222 where R *, Rp, R ^, Ri, Rc and η are as defined, each of the radicals R and R _{7 is} a lower alkyl group and X is a halogen atom. 11. Pressure-sensitive copier paper, characterized in that it has a paper sheet on which at least one Pluurane derivative of the general formula in which each of the radicals R .. and R ₂ is a methyl or ethyl group, each of the radicals R and R is a hydrogen atom, a methyl or ethyl group, Rc is a hydrogen atom or a lower alkyl group, η is an integer of 1 to 5 and R, and B, do not represent hydrogen atoms at the same time, is plotted. 12. Pressure sensitive copier paper according to claim 11, characterized characterized in that there is at least one fluorine derivative according to claim 11 on a single sheet of paper in the form of a solution encased in tiny capsules in a non-volatile solvent and a solid acid having. - 27 - 209832/1222 13. Pressure-sensitive copier paper according to claim 11, characterized characterized in that there is an upper bath to which at least one fluoran derivative according to claim 11 is applied in the form of a solution encased in tiny capsules in a non-volatile solvent, and a bottom sheet coated with a solid acid. 14 · Pressure-sensitive copying paper according to claims 11 to 13, characterized in that it contains a fluoran derivative in which R., in the formula a methyl or Meant ethyl group 15 · Pressure-sensitive copier paper according to claims 11 to 14, characterized in that it is a fluoran derivative contains, in which R, in the formula is an ethyl group means. 16. Pressure-sensitive copier paper according to claims 11 to 15, characterized in that it is a fluoran derivative contains, in which R, - one different from methyl represents lower alkyl group. 17. Pressure-sensitive copier paper according to claims 11 to 13 »characterized in that it is a fluoran derivative contains. 18. Pressure-sensitive copier paper according to claims 11 to 13, characterized in that it contains 3-diethylamino-6-methyl-7- (4'-methyianilino) fluorane as the fluorane derivative. 19. Pressure-sensitive copying paper according to claims 11 to 13, characterized in that it is the fluoran compound 3-diethylamino-6-methyl-7- (2 ', 4'-dimethylanilino) fluoran contains. - 28 - 209832/1222 - do - 20. Pressure-sensitive copier paper according to claims 11 to 13, characterized in that it is used as a fluoran compound _} - Diethylaininc contains ~ 6-ethyl-7-anilinofluoran. 21. Pressure-sensitive copier paper according to claims 11 to 13 »characterized in that it contains 3-diethylamino - ^ - methyl-7-anilinofluorane as the fluorane compound. 209832/1222