DEI0010791MA - - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

Registration date: October 20, 1955. Advertised on November 15, 1956

GERMAN PATENT OFFICE

PATENT APPLICATION

CLASS 57b GROUP I812 INTERNAT. CLASS G 03c -

110791 IVa / 57 b

John Mathers Woolley, Blackley (Great Britain)

has been named as the inventor

Imperial Chemical Industries Limited, London

Representative: Dipl.-Ing. A. Bohr, Dr.-Ing. H. Fincke and Dipl.-Ing. H. Bohr, patent attorneys, Berlin-Lichterfelde West, Freiwaldauer Weg 28

Method and material for the manufacture of photographic

Color images

The priority of filings in Great Britain on October 22, 1954 and October 7, 1955

is used

The invention relates to a new method for the production of photographic color images by color development in the presence of a Color former and on piiotographic material which contains the mentioned color former.

It is known that when a reducible silver salt image with a primary aromatic Amino evolves in the presence of certain isooxazolones is developed, which is a responsive

ίο contain methylene group, dyes of the azomethine series can be obtained. Dyes of this class are generally low in chemical properties Resistance and poor lightfastness.

It has now been found that developing the reducible silver salt with a color developer in the presence of certain derivatives of isooxazolones which do not have a reactive methylene group contained in the isooxazolone ring and which were previously unknown as color couplers

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a completely different kind of color coupling occurs.

According to the invention, a method for Proposed production of photographic color images, which is characterized by that an exposed gelatin-silver halide emulsion layer is coated with a photographic color developer in the presence of a color coupler of the formula

.-C

CO

is developed, where in the given formula Z denotes the atoms which are required are to complement a homocyclic, heterocyclic or polycyclic nucleus, and R Denotes hydrogen or an acyl group.

The nucleus denoted by Z can have substituents, for example halogen, sulfanic acid, carboxylic acid, carboxylic acid ester or amide substituents. Z can, for example, denote the atoms which are required to complete a benzene nucleus or a substituted benzene nucleus, ie the compounds can be β, jz-Behziisooxazolones which are in the 1-, 4-, 5-, 6- or 7-positions May have substituents. The numbering system used in this description for the β, 7-benzisooxazolones is the same as described in "The Ring Index" by Patterson and Capell in Reinhold Publishing Corporation (1940), No. 729.

was ben. As an example of a heterocyclic and polycyclic nucleus is the quinoline nucleus.

The color coupler used in the method according to the invention can be in the developing solution can be applied, or it can be in a photosensitive layer of a multilayer photographic material or in a non-photosensitive layer, which is a Sensitive Schidht is adjacent or that of this through a water-permeable Colloidschidht is separated.

In the latter case, an insoluble color coupler can be used or a soluble color coupler, which is enclosed in particles of water-insoluble but water-permeable material is, but it is preferred to use color couplers which contain a substituent which makes them diffusion-resistant, for example an alkyl chain with at least 5 carbon atoms and, if desired, a solubilizing group.

The color couplers used in the process according to the invention can be prepared by the general procedures used in the synthesis of β, γ-benzisooxazolones, for example by reducing the corresponding o ¹ -nitrobenzoic acid, 3-nitrophthalic acid, sN.itro-o-dhlorphtihal . Acid 2-nitro-4-sulfobenzoic acid, S-octadecyloxy-o-nitrotrimellitic acid, S-nitro ^ -oxyquinoline ^ -carboxylic acid ethyl ester or 2-nitro-terephthalic acid 'to the corresponding o-nitrocarboxylic acid or an ester thereof, for example hydroxylamino compound, through subsequent ring closure, whereupon, if desired, the hydrogen atom bonded to the nitrogen atom is replaced by an acyl radical in which, for example, the compound is heated with acetic anhydride, ethyl chloroformate, p-toluenesulfonyl chloride or phenyl isocyanate. If desired, substituents can also be introduced into the nucleus denoted by Z, or substituents on this nucleus can be modified by known reactions. For example, if nitrophthalic acid is used as the starting material, the 4-carboxy- ^, y-benzisooxazolone formed itself can be used as a color former, or it can be converted into the corresponding 1-acetyl-, i-phenylcarbamyl-, i-carbethoxy or ip -Toluenesulfonylderivat can be converted by substitution of the nitrogen atom or the carboxyl group in the 4-carboxy / ?, y-benzisooxazolone or in its ι-substituted derivatives can be modified, for example, by converting it into the corresponding carboxylic acid chloride, this with an alcohol , such as octadecanol, is reacted, or with an amine, such as. Octadecylamine or with i-amino-2- (N - methyl-N-oetadecylamino) - benzene - 5 - sulfonic acid.

The photographic color developers used in the method according to the invention include the mono-, di- and triamino-aryl compounds one. Particularly among the monoamino developers are the aminophenols and 105. Aminocresols and their halogen derivatives as well as aminonaphthols mentioned.

The developers used in a preferred manner, which in the method according to the invention For best results, the aromatic o- and p-diamines, such as p-phenylenediamine and its substitution products.

The color coupling which occurs in the method according to the invention when an exposed Gelatin-silver halide emulsion with a primary aromatic amino developer in the presence one of the above-mentioned color couplers is treated, leads to a 'surprising and full, come unexpected reaction in which the isooxazolone ring is split and an azo dye is formed, in which the remainder of the oxidation product of the developer to the nitrogen atom is bonded beforehand in the 1-nitrogen atom of the isooxazolone ring has been formed. For example, if 1-phenylcaibamyl-4-carboxy- / 3, 7-benzisooxazolone and as

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J 10791IYa 157 b

Developer p-diethylamino-aniline is used, a dye of the following formula is formed: COOH

, - COOH

! - N = N -

-N (C ₂ H ₅ ),

It should be noted that the acyl substituent on the nitrogen atom of the i-position of the Indazolone ring is split off during color development.

By selecting suitable color couplers, in particular with regard to the atoms which are used in the above given formula the color couplers are denoted by Z, and by selecting suitable developers it is evident to obtain dye images with a wide range of colors.

The color images which are formed by the subject of the invention methods are, as regards their chemical stability and their Liohtechtheit superior to the known Azomethiinfarbstoffbildern, and ^1, the method according to the invention provides a- simple operation to photographic color images with good fastness properties by direct development of a exposed gelatin-silver halide emulsion with a photographic color developer.

The invention is illustrated in the following examples without, however, being restricted thereto. The parts are consigned.

Example ι

A developer solution of the following composition is prepared:

Anhydrous sodium carbonate i6.2

N, N-diethyl-p-phenylenediamine sulfate ... 0.75

Potassium bromide 0.25

Sodium sulfite anhydrous 0.25

ß, ^ -Benzisooxazolone 0.5

Water 250.0

In this solution is at a temperature of 20 ° an exposed photographic silver halide emulsion layer developed. In the exposed parts of the layer, the silver halide is converted into metallic silver, and the yellow azo dyes consisting of the sodium salt of 2-carboxy-4'-diethylami: noazobenzene, gets formed. This yellow azo dye has a better stability to the action of light than the azomethine dyes produced by heretofore known color development processes.

In the developer solution of the above example, the same amount by weight of the N-acetyl derivative of this compound can be used instead of the 0.5 part of β, γ-benzisooxazolone, whereby the same dye is formed and the acetyl groups are split off during the coupling reaction.

Instead of the N, N-diethyl-p-phenylenediamine sulfate, that is used in the developer solution of the above example, 4-Amino-3-methyl-N, N-diethylaniline, 4-amiho-3-ethoxy-N, N-diethylaniline or p-phenylenediamine are used will.

Example 2

Instead of the 0.5 part of ß, ^ -benzisooxazolone used in Example 1, 0.5 part of 4-carboxy- / ?, ^ -benzisooxazolone is used, this substance being produced as follows!

31 parts of 3-nitro-phthalic acid are dissolved in 130 parts of water. This solution is quickly added to a solution of 100 parts of stannous chloride in 100 parts of 35 ⁰ ZoIgCr aqueous hydrochloric acid. Here, heat is developed and a crystalline solid substance is formed. The mixture is cooled to 20 ° and the crystalline product is filtered off, washed first with 20% aqueous hydrochloric acid and then with water and dried. 4-carboxy- / γ-benzisooxazolone is obtained in the form of pale yellow needle-shaped crystals which have a melting point of 190 to 192 ⁰ . The azo dye formed in the exposed parts of the silver halide ^{emulsion consists of the sodium salt of 2,3-dicarboxy-4 /} diethiylaminoazobenzene.

The same dye is obtained if 0.5 part of i-acetyl ^ -carboxy- / ?, y-benzisooxazolone (melting point 212 ⁰ ) is used instead of 0.5 part of 4-carboxy- / ?, γ-benzisooxazolone by heating 4-carboxy- / ?, jz-benzisooxazolone with acetic anhydride.

Example 3

SS in place of the 0.5 parts as used in Example 1, y-Benzisooxazolon are ß 0.5 parts of 6-carboxy, j'-benzisooxazolon used, where this substance is prepared as follows:

16 parts of 2-nitro-terephthalic acid are stirred with 100 parts of water at 10 °, and 12 parts of zinc dust are added at such a rate that the temperature of the mixture does not rise above 15 °. When all the zinc dust has been added, the mixture is stirred for a further 30 minutes at 15 ⁰ long, and the mixture is then filtered. The residue is washed with 50 parts of water, and sulfuric acid is added to the combined filtrates and washing liquids until the mixture contains 10% free sulfuric acid. The solution thus obtained is boiled and then cooled. 6-carboxy- / γ-benzisooxazolone crystallizes out and is filtered off, washed with water and dried. The product is purified by stirring with 20 parts of cold methanol for 15 minutes, filtered off and crystallized from methanol. The thus-formed 6-carboxy / ?, ^ -benzisooxazolon not melt below 300 ^0th The yellow dye formed in the exposed parts of the silver halide photographic emulsion layer consists of

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2,5-Dicarjboxy-4 ^ d \ iäthylärni; noazobenzol. The same dye is obtained if instead of 5 parts 6-carboxy- / ?, y-benzisooxazolone 0jS parts i-acetyl-o-carboxy- / ?, y-behzisooxazolone (melting point 190 ⁰ ) are used, which can be obtained by heating 6-carboxy- / ?, y-benzisooxazolone can be produced with acetic anhydride.

Example 4

Instead of the 0.5 part of ß, jz-benizisooxazolone used in Example 1, 0.5 part of i; henylcarbamyl-4-carboxy- / 3, y-benzisooxazolone is used, this substance being produced as follows:

ι part 4-carboxy / ?, y-benzisooxazolone, 10 parts dry dioxane and 1 part phenyl isocyanate are

. . the cooler together at reflux for 30 minutes cooked. The mixture is cooled and the crystalline precipitates from the solution

ao fabric is nitrided off, washed with methanol and ether and dried. The product melts at 190 ^° .

Example 5

Instead of the 0.5 part ß, y-Benzisooxazoloii; which are used in Example 1, is worked with OjS parts of 1-CaAaIhOXy ^ -CaIbOXy- / ?, y-benzisooxazolon, and this substance is ^{1 produced} as follows:

1 part of 4-carboxy / ?, y benzisooxazolon, 10 parts of chlorobenzene and ¹ 1 part of ethyl chloroformate are combined boiled for 3 hours at reflux cooler. The mixture is cooled and the crystals which separate out from the solution are filtered off, washed with benzene and dried. The product melts at 156 ^° .

B e i s ρ i e 1 6

Instead of the 0.5 parts of β, γ-benzisooxazolone used in Example 1, o, S parts of ι -p-toluenesulfonyl-vi-carboxy- / ?, γ-benzisooxazolone are used, this substance being prepared as follows will:

ι part ^ -Carboxy - /? *, y-benzisooxäzolon is in 10 parts of pyridine dissolved, and 2 parts of p-toluene - sulfonyl chloride are added. The mixture is heated to the boiling point, and 10 parts Water are added. The mixture is left to stand for 10 minutes and then poured into a Poured mixture of 100 parts of water and 20 parts of hydrochloric acid. The separating The syrup is separated off and heated with 10 parts of methanol. The clear solution that forms is cooled, and here 1-p-toluenesulfonyl-4-carboxy- / ?, y-benzisooxazolone from. The product is: filtered and dried. It melts at 2o6 °.

Example 7

Part of the octadecyl ester of i-acetyl-4-caA-oxy- / ?, y-benzisooxazolone is dissolved in 5 parts of dibutyl phthalate, and 1 part of the ammonium salt of sulfonated oleic acid is added. The resulting solution is added at 40 ⁰ 100 parts of a melted gelatin-silver halide emulsion. The mixture is placed in a homogenizer. This mixture is then applied as a layer to a film base and the layer is dried; This layer is exposed through a graduated part and then developed in a photographic color developing solution which contains N, N-diethyl-p-phenylenediamine as a developing substance. The developed silver is bleached and the silver salts are removed by a fixing bath. In this way, a yellow azo dye image is obtained which, in terms of its density gradation, corresponds to the intensity of the light which has passed through the graded part. The octadecyl ester of i-acetyl ^ -carboxy- / ?, y-benzisooxazolone used can be prepared as follows:

2 parts of i-acetyl-4-carboxy- / ?, γ-benzisooxazolone and Lö parts of thionyl chloride are boiled for 2 hours on a reflux condenser. The excess thionyl chloride is distilled off and the Carbonsäürechiorid ¹ is dried in vacuo. A mixture of 1 part of the cafboxylic acid chloride thus formed, 2 parts of octadecariol and 10 parts of benzene are refluxed for 2 hours. The mixture is cooled and the ootadecyl ester of 4-carboxy- / γ-benzisooxazolone which separates out of the solution is filtered off, washed with benzene and dried. It melts at 71 to 72 ⁰ .

Example

Instead of the 1 part octadecyl ester used in Example 7, 1 part i-acetyl- ß, y-benzisooxazolone ^ -carboxyoctadecylamide can be used, which is prepared as follows:

ι part ι -acetyl- / ?, y-benzisooxazolone-4-carbon-'acid chloride is dissolved in 10 parts of benzene and this solution becomes a solution of 3.5 parts Octadecylamine in 10 parts of pyridine and 10 parts of benzene were added. The solution will be Boiled for 5 minutes, and the benzene and excess pyridine are then removed by vacuum distillation removed. The residue is dissolved in 10 parts of methanol and the solution becomes poured into a mixture of 100 parts of water and 10 parts of hydrochloric acid. The resulting white precipitate is filtered off, first with water, then with methanol and finally washed with ether and dried. The product is recrystallized from methanol and then melts at 98 to 100 °.

Example 9

ι Part ß, y-Benzisooxäzolon-4-caf boxy- (2'-N-methyl-N-octadecylamino-5'-sulfo-benz) amide is added to a mixture of 5 parts of methanol and 4 parts of water, and an o , 4% aqueous sodium hydroxide solution is added dropwise until a clear yellow solution has been obtained. The _pH value of this solution is

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Addition of acetic acid or an o, 4% aqueous Sodium hydroxide solution adjusted to 8 and the solution then becomes 100 parts of a molten solution Gelatin-silver halide emulsion added. This emulsion is called a layer

. a support is applied and the layer is dried. This layer is exposed with

a solution of N, N-diethyl-p-phenylenediamine developed, the developed silver is bleached,

ίο and the silver salts are fixed. The layer is washed with water. In this way an orange colored azo dye image is obtained.

- The ß, y-benzisooxazolone - 4 - carboxy - (2'- N - methyl -N- octadecylamino-5'-sulfo-benz) -amide used in this example can be prepared as follows:

2.2 parts of 1-acetyl- / γ-benzisooxazolone-4-carboxylic acid chloride are dissolved in 18 parts of benzene, and the solution becomes a hot solution of 4.5 parts of 1-amino-2- (N-methyl-N-octadecylamino) -benzene-5-sulfonic acid dissolved in a mixture of 10 parts of benzene and 8 parts of pyridine. The solvent is removed by vacuum distillation and the residue is divided into 20 parts Dissolved methanol. This solution is a mixture of 50 parts of ice and 20 parts of a 35% hydrochloric acid added. The one that forms The gummy precipitate is allowed to settle and the supernatant liquid becomes decanted off. 1 The gummy residue is washed with water and then with 100 parts Boiled methanol. The solution thus obtained is cooled, and the pale gray solid substance, which separates out, is filtered off and crystallized from glacial acetic acid. The product melts at 212 °.

Example

Instead of the 0.5 part of β, γ-benzisooxazolone used in Example 1, 0.5 part of 4-carboxy-S-chloro- ^, γ-benzisooxazolone is used, this substance being prepared as follows: 36 parts 3-Nitro-6-chlorophthalic acid are dissolved in 130 parts of water. The solution is quickly added to a solution of 100 parts of stannous chloride in 100 parts of 35% aqueous hydrochloric acid. Here, heat is developed and a crystalline solid substance is formed. The mixture is cooled to 20 ^0, and dais crystalline product is filtered off and then washed first with 20 ° / cent aqueous hydrochloric acid, with water and dried. In this way, 4-CaPbOXy-S-CIhIoT- / ?, is y-benzisooxazolon in the form of pale yellow needle-like crystals obtained, melting at 178 ^0th The yellow dye which forms in the exposed parts of the halide emulsion layer is the sodium salt of 2,3-dicarboxy-4-chloro-4'-dIethylaminoazobenzene. *

B e i s ρ i e 1 11

;: =, In place of the ß, "-Benzisooxazolons, Example 3 Indian developer solution is used in accordance with 5 parts of a io ⁰ / o aqueous solution · ß, y-Benzisooxazolon-o-sulfonic acid are applied, whereby an azo dye is formed which is light yellow in alkaline solution and clear reddish purple in acidic solution.

The ioVoige aqueous solution of ß, jz-benzisooxazolone-o-sulfonic acid used according to this example can be prepared as follows:

2-Niitrotoluene-4-sulfonic acid is used in the usual Way is oxidized with an alkaline permanganate solution to give 2-nitro-4-sulfobenzoic acid.

2 parts of 2-nitro-4-sulfobenzoic acid are stirred into 200 parts of water, which contain 16 parts of ammonium chloride. To this cooled mixture was added 32 parts of zinc dust gradually at a rate such that the temperature did not exceed 30 ⁰ increases. The mixture is then stirred for 30 minutes at room temperature and filtered. The filtrate is strongly acidified by adding hydrochloric acid and boiled in order to bring about the ring closure of the 2-hydroxylamino-4-sulfobenzoic acid and to form the benzisooxazolone-6-sulfonic acid. The solution obtained in this way is being neutralized with sodium carbonate and! filtered. The benzisooxazolone-6-sulfonic acid content of the filtrate is determined by nitration with n-2 sodium nitrite solution, and then water is added to the filtrate in order to bring the concentration of the β, γ-benzisooxazolone-6-sulfonic acid to 10 percent by weight.

Example 12

Instead of the β, γ-benzisooxazolone used in the developing solution of Example 1, 0.5 part of oxyquinoliniisooxazolone is used, which is prepared as follows: One. phötögraph is before SiI be rhalogen diem i u 1 si on ss chi oh t, wel before has been exposed, is developed in the 20 ⁰ warm solution, and the silver and the silver halide in the exposed parts of the layer are removed. The yellowish brown azo dye in the exposed parts of the layer is converted into a clear purple color by treatment with hydrochloric acid.

The oxy-quinoline isooxazolone used in this example can be made as follows: no

20 parts of 4-Oxy-quinoline-2-carboxylic acid ethyl ester are dissolved in 18 parts of concentrated sulfuric acid at a temperature below 30 ^0th 180 parts by weight of a mixture of nitric acid and concentrated sulfuric acid, 10% nitric acid, the mixture is slowly added and after the addition is complete, the mixture is stirred at 30 hour ι ⁰ long. The solution is poured onto 300 parts of ice, and the yellow solid is filtered off and washed free of acid. The filter cake is stirred up with 60 parts of ethanol, and the mixture is heated to boiling and filtered. This filter cake is washed with 60 parts of hot methanol and then recrystallized from 100 parts of acetic acid. In this way, the 3-NitiO-4-oxy-quinoline-2-carboxylic acid ethyl ester

60 »707/313

110791 IVa / 57 b

obtained in the form of small yellow crystals melting ^{at 286 0.} 4 parts of this product are stirred in 60 parts of water containing 2 parts of ammonium chloride, and 4 parts of zinc dust are gradually added over the course of 15 minutes, the temperature being kept ^{below 30 0 by adding ice if necessary.} The mixture then becomes more. Stirred for 15 minutes then filtered. Sufficient hydrochloric acid is added to the filtrate until the mixture turns a strong blue color on Congo red paper. The cloudy suspension thus obtained is boiled for 1 minute, then cooled and filtered, and the mixture is stirred with 50 parts of normal sodium hydroxide solution. Then 1 part decolorization charcoal is added and the suspension is filtered. The filtrate is acidified and the precipitate is filtered off and dried. The product has the following formula

OH

NH,

Example 13

Instead of ι part ß, jz-BcnzAsooxazolon-4-carboxy- (2'-N-methyl-N-oetadecylamino'-5'-sulfobenz) amide, which is used in Example 9, 1 part 4, o-Dicarboxy-7-octadecyloxyb.enzisooxazolon worked, which is prepared in the manner to be described. In this way a yellow azo dye image ^{1 is} obtained. - The 4, o-dicarboxy ^ -octadecyloxybenzisooxazolone, which is used in this example, can be prepared as follows:

5-oxytrimellitic acid is found in the trimethyl ester transferred, other it is heated for 6 hours on the reflux condenser with methanol, the Contains 5 percent by weight anhydrous hydrochloric acid.

15th ¹ Ue of trimethyl ester to contain in 100 parts of oleum containing 20% free sulfur trioxide, not dissolved at a temperature of 30 ^0th This solution is stirred and cooled to below 2O °, and then 7.5 parts of potassium nitrate are added in portions at such a rate that the temperature did not exceed 20 ⁰ increases. When the addition of the nitrate is complete, the solution is stirred for 30 minutes at 25 ° and then poured onto 20 parts of ice. The resulting gummy mass is allowed to settle and the supernatant liquid is poured off. The gum is stirred up with ether and methanol is gradually added until the gum crystallizes out. The crystalline product is filtered off, washed with ether and. dried. The thus-formed 5 oxy-o-nitro-trimellitinsäuretrimethylester is a white solid which melts at 126 ^0th

10 parts of this nitro ester are stirred with 24 parts of octadecyl iodide and 4, δ parts of freshly prepared dry silver oxide for 30 minutes at 100 °. The precipitate of silver iodide that forms is filtered off, washed with ether, and the filtrate and the washing liquids are heated in order to evaporate the ether. 40 parts of methanol are added to the residue remaining after the ether has been removed, and 30% aqueous sodium hydroxide is then gradually added until the mixture remains alkaline after boiling for 5 minutes. The _pH value is the same then more than 10. Then are added 100 parts of water, and the alkaline solution is extracted with 100 parts of ether. The aqueous layer is separated and extracted again with 100 parts of ether. The aqueous layer is separated again and carefully neutralized by adding dilute hydrochloric acid. The leather-colored precipitate thus formed is filtered off, washed with 10% salt solution and dried. In this way a light brown hard wax is obtained which consists of a mixture of S-octadecyloxy-o-nitrotrimellitic acid and its sodium salt, this mixture not having a clear melting point. go

10 parts of this wax, 50 parts of 35% hydrochloric acid, 20 parts of water and 10 parts of stannous chloride are refluxed together for 30 minutes cooked. The suspended oil present at the beginning is colored by a pale straw yellow flaky precipitate replaced. The suspension is cooled and filtered, and the The filter residue is first treated with 15% hydrochloric acid and then washed with water. The product is dried at room temperature and ground to form a buff-colored solid. This product containing the monosodium salt too appears to be used without further purification.

Claims (4)

PATENT CLAIMS: i. Process for the production of photographic images Color images, characterized in that an exposed gelatin-silver halide emulsion layer with a photographic color developer in the presence of a dye coupler dfer formula ■. , -C 3 iZ where Z denotes the atoms, 707/313 110791 IVa / 57 b which are required to create a homocyclic, heterocyclic or polycyclic · To complete the nucleus, and R denotes hydrogen or an acyl group. 2. The method according to claim 1, characterized in that that the color coupler is contained in the developing solution used. 3. The method according to claim 1, characterized in that that the color coupler, in the gelatin-silver-halide emulsion layer of the photosensitive material used. 4. Light-sensitive photographic material for carrying out the process according to Claim 3, characterized in that it is a gelatin-silver halide emulsion layer which has a color complex of the formula ,, - C-COOH N = N-X contains, in which Z has the meaning given in claim 1 and X denotes the group of atoms which together with the group - NH _{2 forms} a primary aromatic amine and wherein the color complex contains a diffusion-proofing substituent and also a solubilizing group.