DE2242693A1 - NEW FLUORANE COMPOUNDS - Google Patents

Description

48 593

ν *

Applicant: NISSO ΚΑΚΟ CO., LTD., 1-6o, 3-Chome, Ukima, Kita-ku, Tokyo (Japan)

New Pluoran connections

The present invention relates to new fluorane compounds . as well as their use as color-forming component in Auf- ' Drawing materials.

The present invention relates to new fluorane compounds of the following general formula:

(D

wherein R is an alkyl group having 5 to 8 carbon atoms represents.

The present invention also relates to a recording method which is characterized in that a .Pluorane compound of the above general formula I in intimate Is brought into contact with an electron accepting substance, the above fluorine compound being a parbe developed.

309 819/1 174

INSPECTED

Fluoran derivatives of the above formula I are substances which are themselves practically colorless. These substances have the Property that when they come into contact with an electron accepting substance, e.g. acids, acid clays, Phenol-formaldehyde resins, etc., develop a black or green color. So if a solution of the mentioned When fluoran derivatives are brought into contact with acid clay in an inert solvent, one develops black color. A deep green color becomes through contact developed this solution with a phenol-formaldehyde resin. Furthermore, a color is developed by being finely powdered Fluoran derivative and finely divided acidic clay or phenol-formaldehyde resin in intimate contact under pressure come, or that a mixture thereof is brought into intimate contact, while this mixture is at least one Temperature above the melting point of one of the two components of the mixture is heated. Because of the above Properties make fluoran derivatives of Formula I above useful as chromogenic materials for use in the production of copier or recording papers, for example pressure sensitive sheets, pressure sensitive Duplicating materials, heat-sensitive recording materials, heat-sensitive copying materials etc. These fluoran derivatives can also be used as chromogenic materials in a recording material for color development be used because printing on the surface of a sheet of paper made with an electron accepting substance is coated, can be done using a pressure solution in which said fluoran derivative is dissolved.

There is a strong need for a chromogenic Material for use in pressure sensitive duplicating sheets; this chromogenic material is said to have the ability on contact with acidic clay to produce black coloring. However, so far it is not

- 3 -30981 9/1174 -

single chroinogenic material known to meet this requirement would correspond. ! Do was surprisingly found, however, that the fluorine an derivatives / ler above formula I according to the invention hacen the property on contact with acidic Tone to develop a deep black color very quickly. By using the new fluoran derivatives according to the invention As a chromogenic material, obshaTb can be as set out above Need to be satisfied.

For developing a black color in a pressure-sensitive copying material, of which the underlying paper is coated with an acidic clay, mixtures of chromogenic materials are known which are suitable Contain amounts of, for example, the following compounds: C.V.L. (capable of developing a blue color), B.L.M.B, (capable of developing a greenish-blue color), 3-Cyclohexylamino-6-chlorofluorane (capable of developing an orange color), Rhodamine-B-lactam (for developing of a red color), etc. Pressure-sensitive reproduction materials made using a However, mixtures of different types of these substances have been produced, have serious disadvantages in that the black color developed thereby loses its hue in an extremely short time when exposed, there with regard to the substances used, differences in the. Consist of lightfastness. Furthermore, the color tends to be theirs Change hue when the recording material is kept for a long time.

According to the present invention, a pressure sensitive Reproduction material can be obtained which does not have the disadvantages mentioned above.

3 (i? ¹ 8 1 9/1 1 7 4

As a substance with a structure similar to that of the fluoran derivatives is similar to the above general formula I, the 3-diethylaraino-6-methyl-7-anilinofluoran is chromogenic Material for use in pressure sensitive duplicating materials known (BE-PS 744 705).

: N-ι

(ID

The inventors of the present invention have found that when the fluoran derivative of the above formula II is brought into contact with acid clay, a purple color develops is surprising, while with the fluoran derivatives of the above general formula I according to the present invention a deep black color is developed.

The fluoran derivatives of the general formula I develop a color not only when they come into contact with acid Clay can be brought, but also when mixed with conventional electron-accepting substances, for example phenol-formaldehyde resins be brought into contact. Accordingly, a set of sheets consisting of a top sheet, its underside with microcapsules containing such a fluoran derivative, e.g. a solution thereof in an inert contains organic solvents, and a, lower sheet, the surface of which is coated with acid clay, Can be used as a pressure sensitive copy material capable of developing a black color on top of that with clay

309819/1 1 7

coated surface of the lower sheet is used,

A corresponding arrangement with such an upper sheet and a lower sheet, the surface of which with a Phenol-formaldehyde resin coated can be used as pressure sensitive copying material that is used for development a green color on the resin-coated surface of the lower sheet. A sheet of paper, that on the surface with a mixture of the above-mentioned microcapsules and one such electron accepting Substance, for example acid clay or phenol-formaldehyde resin. Coated can be used as a pressure-sensitive recording sheet. If words or figures printed or written on the surface of a sheet of paper which surface with fine particles of such an electron accepting substance, for example Acid clay or phenol-formaldehyde resin, coated and thereby containing a solution in an inert organic solvent or an ink-like material a fluoran derivative of the general formula I is used, this solution or this ink-like Material is essentially colorless, the so printed or written ', Vorte or figures will be in black or deep green color recorded on the surface of the leaf. Using a typewriter ribbon, that with such a solution in an inert organic solvent or such an ink-like liquid is impregnated, a paper sheet coated on the surface with an electron accepting substance can be used with written on a typewriter.

On the surface of a sheet of paper, the surface of which is coated with a mixture of fine particles of a fluoran derivative of the general formula I, fine particles' of an electron accepting substance, for example acid clay, phenol

309819/1174

2 2 A 2 6 93

Formaldehyde resin or bisphenol A and a binder, For example, if polyvinyl alcohol has been coated, a color is developed when this surface is coated with a thermal pen or a heat type, and thus such a paper can be used as a heat-sensitive recording material be used. Such a paper can also be used for copying, since the development of pits intimate contact of the fluorane derivative with the electron-accepting substance then takes place when a thin Sheet of an original with a material capable of absorbing infrared rays on its surface (e.g. Chinese ink, black Ti: .to etc.) with figures is provided, brought into close contact with the surface of the paper and with strong infrared radiation is irradiated. The paper can also be written on by applying strong local pressure to the surface of the sheet is applied.

Usable carriers for the microcapsules, electron accepting substances, etc. for these recording materials are high molecular weight substances in the form of films, woven or non-woven fabrics, including papers.

One of the essential properties of the fluoran derivatives of general formula I above is that when they are used as chromogenic materials in recording processes, they very quickly develop a deep black color on contact with acidic clay. Another essential property is that the developed black color has excellent lightfastness. If a dye developed from the fluoran derivative of the formula II is exposed to sunlight for a short time , it turns a pale red ouch, while a dye according to the invention developed from a fluoran derivative of the above general formula I even after long Lioiittoe-

309819/1 174

radiation only changes to a blackish-brown. The third essential property of the fluoran derivatives General formula I is that it has good solubility in various inert organic solvents own. The solubility of the fluoran derivatives according to the invention, for example in an alkylnaphthalene and alkyldiphenyl is about three times that of the fluoran derivative of the formula II. The fourth essential property of the fluoran derivatives according to the invention consists in that by contact with an electron accepting substance developed colors have a so-called 'diazocopy usability.

In addition, the fluoran derivatives of the general formula I have excellent water resistance and do not sublime at all. For these reasons, the new derivatives are extremely valuable substances that are used as chromogenic materials in the Recording technology can be used.

Color shades obtained through contact of the fluoran derivatives of the general formula I with substances that accept electrons are given in Table 1 »It is, however also possible to achieve a change in color with the fluoran derivatives of the general formula I, that these are mixed with other chromogenic materials that develop a different hue, and it is thereby also possible to change the hue of others to change chromogenic materials by mixing them with the fluoran derivatives according to the present invention will-. The light fastness of the fluoran derivatives according to the invention can be enhanced by, for example Ultraviolet absorbers, etc. 'can be added.

The manufacture of a pressure-sensitive opjer sheet

3 0 9819/1 174

using a fluoran derivative of the general formula I can, for example, according to the in.den US-PS 2,548,366, 2,8oo, 458 and 2,969,37o are carried out. When using the fluoran derivatives in heat-sensitive Recording sheets can for example those in Japanese Patent Publication No. 6o4o / i ° <65, 4160/1968 and 14039/1970 are used will.

In Table I below, the color shades and melting points of fluoran compounds are given which are those of the above correspond to general formula 1.

Table I.

Hue of the color developed with an electron accepting substance

η -

Activate
the tone resin Melting black green 159-161 black green 170-173 black green 127-130 black green 65-68

i - C ₅ H ₁ t - C ₅ H ₁ η -

The 3-diethylaroino-6-niethyl-7-ani] inofluoran compounds of the present invention, which correspond to the following general formula

"Q _

3 O 9 8 1 9/1 1 7

where R has the above meaning,

can be prepared in that o- (4-diethylamino-2-hydroxybenzoyl) benzoic acid the formula

H ₅ C ₂

COOH

at -10 to +20 C in concentrated sulfuric acid roughly equimolar amounts with a 4-hydroxy-2-methyldiphenylamine compound the general formula

CH

wherein R has the same meaning as above, is implemented.

The invention is further developed with the aid of the following examples

309819/1174

- ίο -

explained.

Production example 1

7 g of o- (4-diethylamino-2-hydroxybenzoyl) benzoic acid and 7 g of 4-hydroxy-2-methyl-4'-n-pentyldiphenylamine are added to 100 g of concentrated sulfuric acid, and the mixture obtained is left at 0 for 24 hours Stirred up to 10 ° C. The mixture is then poured into 300 ml of ice water, and the precipitated crystals are collected by filtration. The crystals are made alkaline with dilute sodium hydroxide solution and then extracted with 300 ml of toluene. The toluene · and subsequently washed several times with 1 1 of a 2 follow sodium hydroxide solution and 1 1 of a 2 ^c / o ± gen hydrochloric acid water layer. Then the solution is treated with activated charcoal. After filtration, the toluene is distilled off under reduced pressure. 30 ml of isopropyl alcohol are added to the distillation residue. The mixture is heated to reflux and then left to stand overnight. The crystals which have separated out are then filtered off with suction, 6.5 g of 3-diethylamino-6-methyl-7-pn-pentylanilinofluorane of the formula

^C 5 ^H 11

can be obtained in the form of almost white crystals with a melting point of 159 161 C.

309819/1 174

The 4-hydroxy-2-methyl-4'-n-pentyldiphenylamine used here was made as follows. 14 g of 4-amino-m-cresol hydrochloride and 14 g of p-n-pentylaniline were placed in a four-necked flask and added 4 g of zinc chloride. The reaction is carried out at 180-200 ° C. for 3 hours with stirring. then the reaction mixture is washed with a dilute sodium hydroxide solution adjusted to pH 7.0 and extracted with 300 ml of toluene. Afterward the extract is suctioned off and the toluene is distilled off. Obtained on distillation under reduced pressure one 7 g of a distillate with the boiling point 130 200 ° C / 4 mmHg.

Production example 2

10 g of o- (4-diethylamino-2-hydroxybenzoyl) benzoic acid and 10 g of 4-hydroxy-2-methyl-4'-n-octyldiphenylamine are added to 120 g of concentrated sulfuric acid. The mixture is stirred for 24 hours at 0 to 10 ° G and then poured into 500 ml of ice water. The crystal precipitated is collected by filtration. The crystals are made alkaline with dilute sodium hydroxide solution and then extracted with 300 ml of toluene. Subsequently, the toluene several times' with 1 1 of a 2 follow Katronlauge with 1 1 is then washed a 2 ^ hydrochloric acid and with water. Then it is treated with activated charcoal. After filtration, the toluene is distilled off under reduced pressure. 30 ml of isopropyl alcohol are added to the distillation residue, and the mixture is then heated to reflux and left to stand overnight. The precipitated crystals are filtered off with suction, 1 g of 3-diethylamino-6-methyl-7-pn-octylanilinofluorane of the following formula

- 1 P -

3098 19/1174 -

CH ₅

NH \ - / ~ ^C 8 ^H 17

is obtained in the form of almost white crystals with a melting point of 65-68 C.

The 4-hydroxy-2-ethyl-4'-n-octyldiphenylamine used here was made as follows.

14 g of 4-amino-m-cresol hydrochloride, 18 g of p-n-octylaniline and 4 g of zinc chloride were added. The reaction is carried out at 180 ° C. for 3 hours with stirring. Then the reaction mixture is with dilute sodium hydroxide solution adjusted to pH 7.0 and extracted with 300 ml of toluene. The extract is sucked off, and that Toluene is distilled off. Distillation under reduced pressure gives 10 g of a distillate having the boiling point 200 - 240 ° C / 4 mmHg.

example 1

1 g of 3-diethylamino-6-methyl-7-p-n-octylanilinofluoran becomes by heating to 80 ° C in 20 g of alkylnaphthalene (liquid A) solved. In addition, 20 g of gelatin (isoelectric point: 8.0) and 5 g of CM.C. completely in 120 ml Waseer (liquid B) dissolved. Then the liquid A is mixed with the liquid B at 50 - 60 ° C, and the mixture is stirred at high speed, to make an emulsion.

; - 13

3 0 9 8 19/1174

This emulsion is adjusted to pH 8.5 - 9.0. The resulting emulsified liquid is then stirred at high speed for 20 minutes and the pH is gradually adjusted to pH 3.8 with dilute hydrochloric acid or acetic acid. The liquid is cooled to 10 to 20 ° 0, with continuous stirring. 6 g of a formalin solution ( $ 37) are added and stirring is continued for another hour at 10-20 ° C. The. The solution obtained is then adjusted to pH 9.0 with 5% sodium hydroxide solution. The resulting emulsion is slowly stirred for a few more hours, microcapsules forming in the emulsion which enclose an alkylnaphthalene solution of 3-diethylamino-6-methyl-7-pn-octylanilinofluorane. Each of these microcapsules contains a sufficiently solidified film of CM.C. and gelatin. A sheet of paper is coated on one surface with the resulting emulsion and allowed to dry. Separately, a sheet of paper is coated on one surface with an activated clay and allowed to dry. The first mentioned sheet is placed on top of the second sheet so that the coated side of the first sheet comes into contact with the clay coated surface of the second sheet. When words are written on the surface of the first sheet, the written words are quickly developed in black color on the clay coated surface of the second sheet. The words developed in this way changed their hue only slightly to a blackish brown after long exposure to sunlight.

Example 2

1.0 g of S-diethylamino-δ-methyl-T-p-n-octylanilinofluoran becomes dissolved in 20 g of dibutyl phthalate (liquid A). On the other hand, a liquid B becomes in the same way as described in Example 1 prepared. Liquid A and

3 0 9 8 19/1174

-H-

Liquid B are mixed with one another and treated in the same way as described in Example 1 to obtain a Make emulsion. A sheet of paper is coated with the emulsion on one surface and then allowed to dry. Independently of this, a paper sheet is coated on the surface with an I-henol-formaldehyde resin and left to dry. The first sheet is placed on the second sheet so that the emulsion-coated surface of the first sheet comes into contact with the resin-coated surface of the second sheet. V / enn Y / places open written on the surface of the first sheet, the words so written will quickly turn into dark green in color developed on the resin coated surface of the second sheet.

Example 3

1.0 g of 3-diethylamino-6-methyl-7-pn-pentylanilinofluoran are dissolved in 20 g of alkyldiphenyl (liquid A). In addition, the liquid B is prepared in the same manner as described in Example 1. Liquid A and liquid B are mixed together and treated in the same manner as described in Example 1 to prepare an emulsion. A sheet of paper is surface coated with the emulsion and allowed to dry. Independently of this, a sheet of paper is coated on the surface with an activated clay and allowed to dry. The former sheet is placed on top of the second sheet so that the emulsion-coated surface of the first sheet comes into contact with the clay- coated surface of the second sheet. When words are written on the surface of the first sheet, those words are quickly developed in black color on the clay coated surface of the second sheet. The words so developed changed their hue only slightly in; -15-

3 0 9 3 19/117 A

a blackish brown when exposed to sunlight for a long time.

Example 4

1.0 g of 3-diethylamino-6-methyl-7-p-n-pentylanilinofluoran and 0.2 g of benzoyl-leucomethylene blue were added together with 20 g Alkyldiphenyl heated to 100 C ^ to form a solution (liquid A) to manufacture. In addition, a liquid B was prepared in the same manner as described in Example 1. liquid A and liquid B were mixed with one another and then described in the same manner as in Example 1 treated to make an emulsion. A sheet of paper. is coated on one surface with "the emulsion and then left to dry. In addition, a sheet of paper is coated on the surface with an activated clay and left to dry. The first sheet is placed on the second sheet so that the emulsion-coated surface comes into contact with the clay coated surface of the second sheet. When words on the surface of the first Are written on a sheet of paper, these words thus written are quickly developed in pure black color. The so Developed words practically did not change their hue, even when exposed to direct sunlight for a long time became.

Example 5

35 g of 3-diethylamino-6-methyl-7-p-n-pentylanilinofluoran were ground and 1 hour with 150 g of a 10% aqueous Polyvinyl alcohol solution (the polyvinyl alcohol used is , a 98 $ hydrolyzate) and 65 g of water grind to a Manufacture dispersion. The particle diameter of the 3-diethylamino-6-methyl-7-p-n-pentylani] inofluorine after milling it was 1-3 IJnkrön (component A). .Also \ vur-

3 0 Π Β 1 9/1 1 7 4

the 35 g of 4,4'-isopropylidenediphenol (bisphenol A), 150 g a 10 ^ strength aqueous polyvinyl alcohol and 65 g of water together mixed and the mixture was milled for 1 hour. The particle diameter of the bisphenol A after grinding was 1-3 microns (component B).

This was followed by 3 g of component A and 67 g of component B mixed together to make a mixture. A sheet of paper was coated on the surface with the mixture and allowed to dry. It was a obtained heat-sensitive recording material. On the surface of the heat-sensitive recording material ^ a deep green color is developed very quickly through the local application of heat using a thermal needle, a thermal type or a thermal pattern.

Example 6

30 g of 3-diethylamino-6-methyl-7-pn-pentylanilinofluoran and 6 g of 3-diethylamino-6-methyl-7-dibenzylaminofluoran (the last compound is capable of developing a deep red color when brought into intimate contact with bisphenol A. is) are mixed with 150 g of a 10 follow aqueous polyvinyl alcohol solution (the polyvinyl alcohol used here is a 98 ^ iges hydrolyzate) and 65 g of water and ground for 1 hour (component A). In addition, a component B was produced in the same manner as described in Example 5. Furthermore, 35 g of talc with a particle diameter of 10 microns, 150 g of polyvinyl alcohol and 65 g of water were mixed with one another and ground for 1 hour (component C). A mixture of 3 g of component A, 27 g of component B and 40 g of component C was then applied to the surface of a sheet of paper, and. the sheet was then allowed to dry. A thin sheet of paper on which black pencil, black ink, Chinese ink, or other infrared rays - 1 7 -

3093 19/117 /.

Absorbent Parbmaterial a manuscript was written, on the coated side of the first sheet placed. The arrangement was through a Risofax BP-11 machine (a thermal copying machine with an IR radiation source by Pirma Riso Kagaku Kogyo Co., Ltd.), using the words or images of said manuccript corresponding parts were quickly reproduced in black parbe on the coated surface of the sheet.

Example 7

1.0 g 3-diethylamino-6-methyl-7-p-n-per! + Ylanilinofluoran, 5 g dibutyl phthalate,, 10 g castor oil and 5 g chlorinated Paraffin were mixed together to prepare a solution. A rubber stamp or a wooden printing plate were made moistened with the solution. Regardless of this, a sheet of paper was coated on the surface with activated clay and left to dry. When the heated rubber stamp or the wood printing plate in contact with the clay coated Surface of the sheet were brought, were located on the rubber stamp or the wooden plate Yi / orte quickly in black parbe on the clay coated Surface of the sheet reproduced.

- 18 -

309819/1174

Claims (1)

Patent claims: iJ) Fluoran compounds of the general formula wherein R is an alkyl group having 5 to 8 carbon atoms represents. 2.) Recording method, characterized in that one a fluoran compound of the general formula wherein R is an alkyl group having 5 to 8 carbon atoms represents brought into intimate contact with an electron accepting material, the fluoran compound being a Lets color develop. 5.) Recording method according to claim 2, characterized in that 309819/1 17 / » 22A2693 draws the fluoran compound on a surface of a substrate and the electron accepting substance on a surface of another substrate is present. 4.) Recording method according to claim 2, characterized in that that the fluoran compound is contained in microcapsules and together with the electron accepting Material is applied to a surface of a carrier material *. -. 5.) Recording method according to claim 2, characterized in that that the recording is carried out according to the pressure-sensitive copying process. 6.) Recording method according to claim 2, characterized in that that the recording by the thermal copying process is carried out. -,. 7.) Use of compounds of the general formula wherein R is an alkyl group having 5 to 8 carbon atoms represents ^ - ,, as a color-forming component which develops a color in contact with an electron accepting material, in y \ ufzeichnumvsTuateria] ien '.,. - , ■ ·,' - .. ··.; ■ - -,.. , 1 309819/1174 BATH ORIGINAL