DE1217008B - Process for the preparation of water-insoluble monoazo dyes - Google Patents

Description

FEDERAL REPUBLIC OF GERMANY

GERMAN

PATENT OFFICE

EDITORIAL

Int. Cl .:

C09b

German class: 22 a - 1

Number: 1217 008

File number: F 33235IV c / 22 a

Filing date: February 18, 1961

Opening day: May 18, 1966

The subject of patent 1188 229 is a method for the preparation of water-insoluble monoazo dyes of the following general formula

CO co N / \
B. V
H R-NH HO
! \ N / - NH- \ -NH
I. , CO

in which the group R - NH - CO - is in the m- or p-position to the azo group, R is a hydrogen atom, denotes an alkyl or aryl radical, the benzene nucleus A by alkoxy groups and the benzene nucleus B can be substituted by alkyl groups, alkoxy groups or halogen atoms, the diazonium compounds of m- or p-aminobenzoic acid amides of the general formula

R-NH-CO

in which R denotes a hydrogen atom, an alkyl or aryl radical and the benzene nucleus A through Alkoxy groups can be substituted with 5- (2 ', 3'-oxynaphthoylamino) benzimidazolones, which are substituted in the benzene nucleus of the benzimidazolone radical by alkyl groups, alkoxy groups or halogen atoms can, in substance, on the fiber or on another substrate.

The water-insoluble monoazo dyes obtainable by the process mentioned have good ones to very good light fastness and very good solvent fastness and are suitable for production of printing inks and for the preparation of colored lacquers. They can also be used for coloring rubber and plastics, especially polyvinyl chloride, can be used.

In a further embodiment of this inventive concept, it has now been found that water-insoluble monoazo dyes with similarly good fastness properties are obtained if, in the process of the main patent, instead of the diazo compounds of m- or p-aminobenzoic acid amides, processes for the preparation of
water-insoluble monoazo dyes

Addendum to the patent: 1188 229

Applicant:

Farbwerke Hoechst Aktiengesellschaft

formerly Master Lucius & Brüning, Frankfurt / M.

Named as inventor:

Dr. Karl Schilling, Frankfurt / M.-Höchst;

Dr. Erich Dietz, Kelkheim (Taunus)

Diazo compounds of primary amines of the benzene series, those in the benzene nucleus by non-water-solubilizing Groups - with the exception of the group R - NH - CO - (R here denotes a hydrogen atom or an alkyl or aryl group) - may be substituted.

The new dyes can also be used in substance, on the fiber or on another Make substrate. For this purpose, primary amines of the benzene series, such as aminobenzene, l-Ammo-2-fluorobenzene, l-amino-2-chlorobenzene, l-amino-4-chlorobenzene, l-amino-3-bromobenzene, 1 - amino - 3 - iodobenzene, 1 - amino - 2 - methylbenzene, l-amino-4-methylbenzene, l-amino-2-methoxybenzene, 1 - amino - 2 - nitrobenzene, 1 - amino - 3 - nitrobenzene, 1 - amino - 4 - nitrobenzene, 1 - aminobenzene - 2 - carboxylic acid methyl ester, 1 - amino - 2,4 - dimethylbenzene, l-amino-i-methyl-4-chlorobenzene, l-amino-2-methyl-5 - chlorobenzene, 1 - amino - 2 - methyl - 4 - nitrobenzene, l-amino-2-methoxy-4-chlorobenzene, l-amino-2-methoxy-5-chlorobenzene, l-amino-2-methoxy-4-nitrobenzene, l-amino-2-nitro-4-methylbenzene, 1-amino -2-nitro-4-methoxybenzene, l-amino ^ -nitro ^ -acetaminobenzene, l-amino-2,5-dichlorobenzene, 2-amino-4,4'-dichlorodiphenyl ether or l-amino-2,4,5-trimethylbenzene, in Usually diazotized and in alkaline, neutral or acidic medium, preferably in neutral to weakly acidic medium, combined with the 2 ', 3'-oxynaphthoyl compound of 5-aminobenzimidazolone.

Instead of the 2 ', 3'-oxynaphthoyl compound of 5-aminobenzimidazolone, the corresponding

609 569/417

3 4

corresponding, in the benzene nucleus of the Benzimidazolonrestes the products according to the invention for colors in the

be used by alkyl groups, alkoxy groups or halogen spinning pulp,

atoms substituted derivatives, such as. B. 5- (2 ', 3'-Oxy- Dem from U.S. Patent 2,156,731

naphthoylamino) -6-chlorobenzimidazolone, 5- (2 ', 3'-oxy- known dye from diazotized 3-nitroaniline

naphthoylamino ^ -cMor-benzimidazolon, 5- (2 ', 3'-oxy- 5 and the anilide of 4'-oxy-5'-carboxy-3,4 * benzo-

naphthoylamino) -6-methyl-benzimidazolone, 5- (2 ', 3'-acridone is the dye available according to the procedure.

Oxynaphthoylamino) - 7 - methyl - benzimidazolone, substance of diazotized 3-nitroanine and 5- (2'-oxy-

5 - (2 ', 3' - Oxynaphthoylamino) - 6 - ethoxy - benzimide- 3'-naphthoylamino) -benzimidazolone in the light-

azolon, 5 - (2 ', 3'- oxynaphthoylamino) - 7 - bromobenz- fastness of printing dyeings, fastness to bleeding

imidazolone, can be used. io of the polyvinyl chloride dyeings and in the solution

Far superior to those used for the production of the process-related fastness.

borrowed monoazo dyes used azo compo- In the following examples behave

nents can be according to known methods, for example parts by weight to parts by volume such as grams to milliliters, wise by reacting the 2,3-oxynaphthoic acid

chloride with an optionally substituted 15 example
5-Amino-benzimidazolone in a solvent suitable for this reaction, for example 7.6 parts by weight of methyl 2-aminobenzoate, toluene or pyridine. are known in a known manner using

For the production of the pigments, 100 parts by volume of 2N hydrochloric acid and 25 parts by volume are found Sometimes it is expedient to diazotize the coupling in the form of 20 2 n sodium nitrite solution. The diazo solution to carry out that the diazo compound is in aqueous with 5 parts by volume of a 10 weight percent Medium is presented. After adding a sodium-aqueous solution of an emulsifying agent (reaction acetate, an alkaline solution of the product of 1 mol of oleyl alcohol and 30 mol of ethylene-azo component is allowed to do so or add a sodium oxide) and 100 parts by volume of 2N sodium acetate solution acetate-acetic acid buffer mixture and leaves the 25 added.

Diazo compound and the alkaline solution into this diazo solution is allowed at 5 ⁰ C

Azo component run in at the same time. rapid stirring the solution of 17 parts by weight

The dyes obtainable according to the invention are 5 - (2 ', 3' - oxynaphthoylamino) - benzimidazolone in partly of hard grain and can produce 65 parts by volume of 2N sodium hydroxide solution and 400 parts of water the full color strength either in the form of an aqueous 30 and 2 parts by volume of the 10 weight percent aqueous Paste, optionally with the addition of an organic solution of the emulsifying agent listed above to the solvent, run under pressure to temperatures over.

100 ° C, preferably 120 to 180 ° C, heated, after the coupling is completed with steam

or in the form of the aqueous pastes or the dry 80 ° C., the dye is suctioned off, washed out

Dye an aftertreatment with organic 35 and dried.

Solvents are subjected. The dye is made with 250 parts by volume of pyridine

the application of compounds such as B. with stirring and reflux for 2 hours

PyridinjDnriethylformamidjN-Methylacetamidjl ^ di- HO ⁰ C heated. Then one sucks off at 80 ° C, washed

chlorobenzene or phosphoric acid trisdimethylamide, thoroughly dry with hot water and dry

if necessary at an elevated temperature, as appropriate 40 6O ⁰ C.

proven. Mari receives 25 parts by weight of a red pigment

This post-treatment can be avoided by having a high color strength and very good lightfastness, one the coupling at elevated temperature, preferential solvent fastness, overspray fastness and ID cards 50 to 90 ° C, or in the presence of anion blood fastness in plasticized polyvinyl chloride, active, cationic or non-ionic emulsions 45

gators, such as paraffinsulfamidoessig- Example 2
acid sodium (the underlying paraffin rest corresponds to a hydrocarbon fraction of 16.2 parts by weight of molten l-amino-2,5-di-boiling range 180 to 210 ⁰ C), the sodium salt of chlorobenzene in 100 parts by volume of 2N hydrochloric acid Schwefelsäureesters of the reaction product of 5 ° stirred at 9O ⁰ C. With vigorous stirring add 2,4,6-tributylphenol with ethylene oxide, furthermore oleyl, add 30 parts by volume of 10 η-hydrochloric acid, cool amine acetate, distearyldimethylammonium chloride or down to 10 ⁰ C, add 100 parts by weight of ice and add the reaction product of 1 Moles of oleyl alcohol are diazotized by passing 50 parts by volume of 2N sodium with 30 moles of ethylene oxide or emulsifier mixtures, nitrite solution fairly quickly under the surface or by letting the dye run after 55% of the liquid. The mixture is stirred ¹ Z ₂ hours completion of coupling, in aqueous suspension at after, removes excess nitrous acid at elevated temperature with a non-water-soluble aminosulfonic acid and the solution is clarified by FII organic solvent, optionally in trate counter. The clear, pale yellowish diazo solution was treated with an emulsifier. is diluted to 500 parts by volume with water.

The new monoazo dyes are water-insoluble 60 Furthermore, 36 parts by weight of 5- (2 ', 3'-Oxynaph-

pigments which are very good solution thoylamino) benzimidazolone in 200 parts by volume of 2N Na * distinguish medium and light fastness. They are suitable dissolved in tronlax. The solution is 4 parts by volume

for the production of printing inks and for a 10 weight percent aqueous solution Preparation of colored lacquers. You can also use the emulsifier (reaction product of 1 mole of oleyl dye of rubber, of natural resins and alcohol with 30 mol of ethylene oxide) and added

of polymerisation and condensation resins, diluted 500 parts by volume.

but especially for the fast dyeing of poly. Both solutions are left at 10 ° C. with rapid vinyl chloride, can be used. Furthermore, stirring can be carried out simultaneously and at the same speed

in a buffer solution of 50 parts by volume of 2η-acetic acid, 100 parts by volume of 2N sodium acetate solution, 100 parts Water and 3 parts by volume of the 10 weight percent solution of the above-mentioned emulsifier.

After the coupling has ended, 35 parts by volume of 10 η hydrochloric acid are immediately added and the dye is sucked off away. After washing with water and drying, 54 parts by weight of a brown pigment are obtained of hard grain and poor color strength.

The dye is with 360 parts by volume of pyridine with stirring and reflux for 2 hours 110 ° C heated. It is diluted with 100 parts by volume of water, the dye is filtered off with suction and washed with hot Water until it is colorless and dries it at 60 ° C.

48 parts by weight of a brown pigment of soft grain and great color strength are obtained. It is characterized by high lightfastness, good solventfastness and very good fastness to bleeding in polyvinyl chloride.

Example 3

16.2 parts by weight of l-amino-2,5-dichlorobenzene are melted on a steam bath, and poured into 50 parts by volume of 2N hydrochloric acid, which had previously heated to 95 ⁰ C. Then 40 parts by volume of 10N hydrochloric acid are added and, after addition of ice, diazotization is carried out with 20 parts by volume of 5N sodium nitrite solution. Furthermore, 33 parts by weight of 5- (2 ', 3'-oxynaphthoylamino) benzimidazolone are dissolved in 400 parts by volume of water and 130 parts by volume of 2N sodium hydroxide solution.

The solution of the diazo compound and the solution of the azo component is then allowed at temperatures below 2O ⁰ C in 20 to 30 minutes in a submitted buffer solution consisting of 200 parts by volume of water, 100 parts by volume of 2 N acetic acid, 100 parts by volume of 4 N sodium acetate solution and 8 parts by weight oleylamine acetate, drop. After the coupling has ended, the mixture is heated by passing in steam

1 hour at 95 to 100 ° C and then works up in the usual way. 53 to 55 parts by weight of one are obtained brown pigment of excellent lightfastness and good solvent, spray and Fastness to bleeding. A practically identical product is obtained if one uses oleylamine acetate instead of oleylamine acetate the distearyl-dimethylammonium chloride is used as an emulsifier.

Example4

8.4 parts by weight of l-amino-2-methoxy-5-nitrobenzene are diazotized with 100 parts by volume of η 2-hydrochloric acid and 25 parts by volume of 2-n nitrite solution at 5 to 1O ⁰ C. The clarified diazo solution is 75 parts by volume

2 N sodium acetate solution and 5 parts by volume of a 10 weight percent aqueous solution of an emulsifying agent (Reaction product of 1 mole of oleyl alcohol and 30 moles of ethylene oxide).

To this solution, the solution -benzimidazolone in 65 parts by volume 2 passes at 10 ⁰ C of 17 parts by weight of 5- (3'-oxynaphthoylamino 2 ') N sodium hydroxide, 400 parts water and 2 parts by volume of a lOgewichtsprozentigen aqueous solution of the above-mentioned emulsifying agent.

After the coupling has ended, the mixture is heated to 80 to 90 ° C. with steam and the dye is sucked off off, wash off and dry.

The dye is heated for 2 hours at 110 ⁰ C in a vessel equipped with a stirrer and reflux condenser with 250 parts by volume of pyridine. At about 8O ⁰ C, the dye is suction filtered, washed with hot water until the effluent was colorless and dried at 6O ⁰ C.

25 parts by weight of a pigment of great color strength and soft grain, the bordo-colored one, are obtained Shades of excellent light fastness, good solvent fastness and perfect fastness to bleeding supplies its colorations in plasticized polyvinyl chloride.

Example 5

7.6 parts by weight of l-amino-2-methyl-4-nitrobenzene are diazotized with 100 parts by volume of η 2-hydrochloric acid and 25 parts by volume 2 N sodium nitrite solution at 5 to 1O ⁰ C. The clarified diazo solution is mixed with 75 parts by volume of 2N sodium acetate solution, 20 parts by volume of 2η-acetic acid and 5 parts by volume of a 10 weight percent aqueous solution of an emulsifying agent (reaction product of 1 mole of oleyl alcohol and 30 moles of ethylene oxide).

The solution of 19 parts by weight of 5- (2 ', 3'-oxynaphthoylamino) -6-methylbenzimidazolone runs into this solution with vigorous stirring at 10.degree in 85 parts by volume of 2 N sodium hydroxide solution, 400 parts of water and 2 parts by volume of the 10 weight percent aqueous Solution of the above-mentioned emulsifier.

After coupling is complete, the dye is heated with steam at 8O ⁰ C, filtered off, washed and dried. The dye is then stirred with 250 parts by volume of pyridine at HO ⁰ C for 2 hours, filtered off with suction while warm, washed out with hot water and dried.

27 parts by weight of a pigment of soft grain and good color strength, the maroon tones, are obtained provides and is characterized by very high lightfastness as well as excellent solventfastness and bleeding resistance of its dyeings in plasticized polyvinyl chloride excels.

Example 6

15.3 parts by weight of 1-amino-2-methyl-4-nitrobenzene are added to 150 parts by volume of ice water and 60 parts by volume 5 η-hydrochloric acid is diazotized with 20 parts by volume of 5N sodium nitrite solution. Furthermore, 35 parts by weight of 5 - (2 ', 3' - oxynaphthoylamino) - 6 - methylbenzimidazolone dissolved in 400 parts by volume of water and 150 parts by volume of 2N sodium hydroxide solution.

The diazo compound and the alkaline solution of the azo component are then left in for about 20 minutes at 10 to 15 ° C at the same time and with vigorous stirring into a mixture provided from 150 parts by volume of water, 100 parts by volume of 2 n-acetic acid, 100 parts by volume of 4 n-sodium acetate solution and 8 parts by weight oleylamine acetate, drop. The coupling is immediately after the addition of the azo and diazo components completed. The aqueous suspension of the monoazo dyestuff formed is thereupon with 30 parts by weight of paraffinsulfamidoessigsaurem Sodium (the underlying paraffin residue corresponds to a hydrocarbon fraction from the boiling range 180 to 210 ° C) added aqueous emulsion of 100 parts by weight of 1,2-dichlorobenzene

7 8

and by introducing steam for 30 minutes to a 95 10 weight percent aqueous solution of the above heated to 100 ° C. This is followed by a more commonly used emulsifier. The clutch is instant Worked up in a manner that gives 72 to 74 Ge complete.

important parts of a chestnut pigment with good light, the coupling mixture is heated with steam

Solvent and overspray fastness. 5 95 ⁰ C, sucks off the dye, washed with water

thoroughly and dry at 60 ° C.

Example 7 This gives 30 parts by weight of a violet one

Pigments of moderate color strength.

15.3 parts by weight of 1-amino-2-methyl-4-nitrobenzene The dye is mixed with 250 parts by volume of pyridine

are, as described in Example 6, diazotized and io with stirring and reflux for 1 hour heated with 35 parts by weight of 5- (2 ', 3'-oxynaphthoylamino) - 110 ° C. After diluting with the same 6-methyl-benzimidazolone coupled. When the volume of water has ended, it is suctioned off at 80 ° C., with Coupling, the mixture is washed out by 30% by weight of hot water and dried at 60 ° C, share paraffinsulfarnidoessigsaurem sodium (the one gets 26 parts by weight of a grain-soft

The underlying paraffin residue corresponds to a carbon pigment of great color strength, which has a high light hydrogen fraction from the boiling range of 180 to 210 ° C) fastness,
and 100 parts by volume of water and heated by Example 10

Introduce steam for 1 hour at 95 to 100 ° C. ^P.

Then you work up in the usual way and get 16.9 parts by weight of l-amino-2-methoxy-4-mtroben-

70 to 72 parts by weight of a chestnut pigment of 20 zol are in 150 parts by volume of ice water and 60 parts by volume Fastness to light, solvents and overspray. Lumteile 5 η-hydrochloric acid diazotized. Also be

33 parts by weight of 5- (2 ', 3'-oxynaphthoylamino) -benz-

Example 8 imidazolone in 400 parts by volume of water and 130% by volume

lumteile 2 η-sodium hydroxide solution dissolved.

14.2 parts by weight of 1-amino-2-methyl-5-chlorobenzene 25 The diazo compound and the solution of the azo clay with 200 parts by volume of 2η-hydrochloric acid and 50 vol. component one then leaves in about 20 minutes Divide 2 n sodium nitrite solution diazotized at 5 ° C. Temperatures below 20 ° C simultaneously and below The clarified diazo solution is mixed with 150 parts by volume vigorously in a mixture 2 n-sodium acetate solution and 10 parts by volume of the 10--150 parts by volume of water, 100 parts by volume of 2 n-vinegar percentages by weight aqueous solution of an emulsifying acid, 100 parts by volume of 4N sodium acetate solution and by means of (reaction product from 1 mol of oleyl alcohol, 8 parts by weight of oleylamine acetate. and 30 moles of ethylene oxide). when the coupling is ended, the

To this solution runs under vigorous stirring weight share paraffinsulfamidoessigsaurem sodium beil0 ^o CdieLösungvon35Gewichtsteilen5- (2 ', 3'-oxy- (paraffin remaining underlying corresponds to a naphthoylamino) benzimidazolone in 130 parts by volume of 35 hydrocarbon fraction having a boiling range from 180 to 2 N sodium hydroxide, 800 parts of Water and 4 parts by volume 210 ° C) aqueous emulsion of 100 Ge of a 10 weight percent aqueous solution of the parts by weight 1,2-dichlorobenzene was added and the above-mentioned emulsifier. Introduction of steam for 30 minutes at 95 to 100 ° C

After the coupling has ended, the mixture is heated. Subsequently, in the usual manner aufmit steam to 8O ⁰ C, sucks the dye, washed worked 40 and there is obtained 72 to 74 parts by weight of it and dried at 60 ° C. of a violet pigment excellent in light

The dye is fast with 400 parts by volume of pyridine and good solvent, spray-over and with stirring and reflux for 2 hours.
boils. The mixture is then diluted with about

the same volume of water and soak the dye 45 Example 11

fabric off. After washing with hot water

and drying at 60 ° C. gives 50 parts by weight of 7.6 parts by weight of 1-amino-2-methyl-4-nitrobenzene

a deeply colored pigment with a soft grain. are with 100 parts by volume of 2N hydrochloric acid at 5 to Its bordeaux red color is distinguished by stirring at 10 ° C and containing 25 parts by volume of 2 N sodium good fastness to light, good fastness to solvents 50 nitrite solution diazotized. The clarified diazo solution will and good resistance to bleeding in plasticized with 75 parts by volume of 2N sodium acetate solution and Polyvinyl chloride. 5 parts by volume of a 10 weight percent aqueous

Solution of an emulsifier (reaction product from

Example 9 1 mol of oleyl alcohol and 30 mol of ethylene oxide)

55 places.

8.4 parts by weight of l-amino-2-methoxy-4-nitrobenzene The solution of this solution flows at 10.degree

using 100 parts by volume, 17 parts by weight of 5- (2 ', 3'-oxynaphthoylamino) -benz-2η-hydrochloric acid and 25 parts by volume of 2 N sodium nitrite imidazolone in 65 parts by volume of 2 N sodium hydroxide solution, 400 parts by volume at temperatures below 10 ⁰ C diazotized. 100 parts by volume of water and 2 parts by volume of a 10 weight-clarified diazo solution are mixed with 75 parts by volume of 2N Na 60 percent aqueous solution of the above-mentioned trium acetate solution and 5 parts by volume of a 10% emulsifying agent. Shortly after the end of the feed, the weight percent aqueous solution of an emulsifying agent is complete.

by means of (reaction product of oleic acid chloride and one heats with steam to 70 to 80 ° C, sucks the

N-methyltaurine) added. Dyestuff runs off into this diazo solution, washes out with water and dries under the surface 65 with rapid stirring at 10 ° C. The dyestuff with 250 parts by volume of pyridine becomes the solution of 17 parts by weight of 5- (2 ', 3'-Oxynaph- 2 hours heated with stirring to HO ⁰ C, at 60 ° C thoylamino) benzimidazolone in 65 parts by volume 2 η- and washed out with hot water. Sodium hydroxide solution, 300 parts of water and 2 parts by volume of the After drying at 60 ° C, 20 parts by weight

parts of a pigment that delivers Bordo tones and has very good fastness properties, especially one exceptionally high lightfastness.

In the table below, a few more combinations are put together that can be worked through

10

Coupling obtained according to the method described in the preceding examples and which is carried out by high light fastness, good solvent fastness and good bleeding fastness of their dyeings in polyvinyl chloride distinguish.

Diazo component Azo component hue l-amino-2-chlorobenzene 5- (2 ', 3'-oxynaphthoylamino) benzimidazolone Brown l-amino-3-chlorobenzene the same Red 1-amino-2-methoxy-4-chlorobenzene the same Ruby red 1-aniino-2-: methoxy-5-chlorobenzene the same Bordo 1-amino-2-methyl-4-chlorobenzene the same Bordo l-Amino ^ -nitro- ^ acetaminobenzene the same Bordo 4,4'-dichloro-2-aminodiphenyl ether 5- (2 ', 3'-oxynaphthoylamino) -7-chlorobenz-
imidazolone Red 1-amino-2-methoxy-4-nitrobenzene 5- (2 ' ₅ 3'-oxynaphthoylamino) -6-chlorobenz-
imid.a7o1on Marron 1-amino ^ -methoxy ^ -nitro-S-methylbenzene JL.LJLI. Au. CIZj VJ jWJ XJ.
5- (2 ', 3'-oxynaphthoylamino) benzimidazolone Marron 1-amino-2,5-dimethoxy-4-nitrobenzene the same Bordo 1-amino ^ -methoxy-S-methyl-S-nitrobenzene the same Red

Claims (1)

Claim: Process for the production of water-insoluble monoazo dyes in modification of the Method according to patent 1188,229, thereby characterized that here the diazo compounds of primary amines of the benzene series, the groups that do not make water soluble in the benzene nucleus - with the exception of the group R - NH - CO -, in which R is a water torratome or an alkyl or aryl group - may contain, with 5- (2 ', 3'-oxynaphthoylamino) -benzimidazolones, which can be substituted in the benzene nucleus of the benzimidazolone radical by alkyl or alkoxy groups or halogen atoms, in Substance, on the fiber or on another substrate in alkaline, neutral or weak acidic medium with the formation of water-insoluble azo dyes of the general formula HO CO-NH-i A-N = couples, in which A denotes a residue of the benzene series, that in the benzene nucleus by non-water-solubilizing Groups - with the exception of the group R - NH - CO -, in which R is Means hydrogen atom or an alkyl or aryl group - can be substituted, and the benzene nucleus B can be substituted by alkyl or alkoxy groups or by halogen atoms. Considered publications:
U.S. Patent No. 2156,731. When the application was announced, two coloring tables with explanations were laid out. 609 569/417 5.66 © Bundesdruckerei Berlin