DE1543571A1 - Condensation products and processes for their manufacture and use - Google Patents

Description

FARBENFABRIKEN BAYER AG

LlVERKU SEN-kyerwMk Faceitt-AbuUuag Ut / EK

Feb 10, 1966

Condensation products and processes for their manufacture and use

Condensation products from unsulfated diaryl ethers, salicylic acid and formaldehyde are described in German Patent 728 described. Products of this type are only very limited for the tanning of hides because of their poor solubility in the acidic pH range usable? in the range of approximately pH 3.5, which is optimal for binding phenolic tannins, they can only be avoided special and additional working conditions, e.g. under the preceding or use subsequent acidification. The patent also mentions the possibility of using the condensation products of, for example, diaryl ethers, salicylic acid and formaldehyde, to sulfonate afterwards. Nothing is said about the properties of the products available in this way.

It has now been found that valuable new condensation products can be obtained obtained if 1 mole of diphenyl oxide sulfonic acid is obtained with approximately 0.5-4 moles of an aromatic oxycarboxylic acid, preferably salicylic acid, and approximately 1-4 moles of formaldehyde or formaldehyde-releasing Agents condensed in acidic medium. According to a preferred embodiment, 1.5 to 2.2 mol of the

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aromatic oxycarboxylic acid and 1.5 to 2.2 moles of formaldehyde or formaldehyde releasing agent.

The condensation according to the invention takes place in the acidic range below pH 2.0 and at an elevated temperature, for example in the range from 80 to 115 ° C and preferably in the range from 100 to 105 ° C. Conveniently, the sulfonation of the Diphenyl ether sulfonic acids formed from diphenyl ether. and small amounts of sulfuric acid, which are not converted during the sulfonation have been used to acidify the condensation mixture.

The diphenyl oxide sulfonic acids are primarily mono- or disulfonic acids or mixtures of such sulfonic acids into consideration. For the sulfonation of diphenyl oxide, for example by action of sulfuric acid monohydrate or chlorosulfonic acid takes place at elevated temperature, one can either use pure diphenyl oxide or preferably use technical mixtures, such as those obtained in the production of phenol from chlorobenzene and which, in addition to diphenyl oxide, contain various other phenols, such as o- and p-hydroxydiphenyl, as impurities. Such Impurities affect the properties of the invention available condensation products, e.g. in their Tanning effect, no.

The aromatic oxycarboxylic acids used are preferably salicylic acid. However, other aromatic oxycarboxylic acids can also be used use such as o-cresotinic acid and 3-chloro-2-ox3rbenzoic acid.

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The compounds known in the art can be used as formaldehyde-releasing agents, for example aqueous formaldehyde solutions, paraformaldehyde or hexamethylenetetramine »

The condensation of the starting products is generally carried out until complete implementation or until complete disappearance of formaldehyde. In the course of the Reaction, the condensation product formed precipitates out in a resinous form. For working up the reaction mixture can be neutralized with ammonia water and the resulting solution with organic acids, for example acetic acid Set a suitable acid number for the intended use, e.g. for sole or replacement tanning agents. the However, condensation products can also be worked up by spray drying the reaction mass, the product being in powder form is obtained. This, too, can be adjusted to a desired acid number with suitable powdery organic acids will.

The new condensation products obtainable according to the process are valuable tannins and can be used, for example, as Use replacement and retanning agents excellently for tanning hides and leather.

A special application of the condensation products obtainable according to the process lies in the production of shrink leather.

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According to, for example, from the German Auslegeschriften 1 I50 and 1,158,660 known processes, shrink leather is obtained in such a way that animal pelts are treated with mineral acid adjusted synthetic tanning agents containing methylol groups and then tanned with chrome tanning agents. In terms of

The needs of the practice, especially for labor -saving tanning processes in chro-leather factories, are aimed at processes according to which shrink leather is not manufactured in a special production process, but rather the entire pelt material of a uniform water workshop treatment and. Can be subjected to chrome tanning "which is then able to process portions of the material to shrink leather after sorting of the different types of leather. The use of the Ti-duen condensation products available in accordance with the process enables chrome leather, including sub-assortments, to be processed into shrink leather after folding. The chrome leather is treated in a short liquor or, depending on the desired shrinkage grain, in a longer liquor with the new condensation products obtainable according to the process or, after a preliminary run, in weak acid, preferably acetic acid or glutaric acid, with neutral condensation products. treated in the tanning barrel of the type obtainable in accordance with the procedure. If the fulling effect is good, it can be used on this

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Ways an even shrinking effect right into the Flemings achieve. Chrome leathers treated according to the process are also characterized by particularly good fullness in the loose ones structured areas of skin. Particularly suitable for the Shrink leather production after chrome tanning is calf, Goat and other small animal skins, in particular imported goods pre-tanned with chrome, so-called "wet-blue" leather. Also on chrome-tanned Cattle necks and skins as well as Chevreaux leather from two-bath chrome tanning can be used to achieve a well-profiled, even shrinking effect. A particularly noteworthy ^ The advantage of the new condensation products obtainable according to the process is that they are not only available in alkaline and neutral area in the form of their salts but also in weakly acidic areas are readily water-soluble. Settings with one i pH of 3.0 to 3.5 can be used for tanning without the risk of unwanted precipitations.

The parts and parts by weight listed in the following examples.

example 1

170 parts of diphenyl oxide are mixed with 128 g of sulfuric acid with stirring and heated 1 hour at 130 ⁰ C to give a mixture of mono- and Diaulfonsäuren of Biphenyläther low Kengen unreacted sulfuric acid is obtained. After cooling the reaction mass to 80 ~ 9O ⁰ C 100 parts of water and 276 parts of salicylic acid are added. 210 parts of aqueous 30% formaldehyde are then left with constant stirring

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run up. When the reaction mixture is heated to 85-90 ° C., a clear solution is formed. The mixture is then condensed for 8-10 hours with constant itching at 100-105 ⁰ O until no more formaldehyde can be detected. A resinous paste begins to precipitate after approx. 2 hours. After the condensation has ended, the reaction mixture is neutralized with ammonia water to pH 3.5-4.5. The condensate obtained can now be isolated as such, for example by spray drying, or first, for example with acetic acid, adjusted to an acid number suitable for use for sole or substitute tanning and then used for tanning in this or in isolated form. The spray-dried product can be adjusted to the desired acid number with suitable organic acids before or after the spray-drying.

Example 2

170 parts of diphenyl be sulfonated as described in Example 1, "175 parts of sulfuric acid and then with 100 parts Yfesfl * r, and 138 parts of salicylic acid while stirring, and anschlieesend with 105 parts of 30 # sodium Pormaldehyd in 3 portions at 100 - added 105 ⁰ C. After 8-10 hours of condensation, the formaldehyde is completely consumed. After neutralization with ammonia water or sodium hydroxide or potassium hydroxide solution up to z \ x pK 3.5-4.2, it is spray-dried. * after spray drying with solid organic acids.

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Example 3

170 Parts of a crude diphenyl ether, have been eliminated from the alkali washing phenols largely be sulfonated with 147 g of sulfuric acid monohydrate one hour "at 130 C with stirring, The Diphenyläthermono- and obtained disulfonic acid mixture is heated to 80 -. Cooled 90 ⁰ C and under stirring with 100 parts of water and 276 parts of salicylic acid mixed Thereafter, 210 parts aqueous 30 # sulfuric PormaldehydlöauFig with intensive stirring run left During heating the reaction mixture to ^σ -... 90 ⁰ C. a clear red-brown solution after might pass / 'strongly exothermic reaction is 6-8 hours with stirring at 100 ^G C - 105 ⁰ C until no condensed formaldehyde longer detectable · After about 2 hours begins to precipitate a resinous paste * After condensation is complete, the reaction mixture with ammonia water to pH 3.5 is - 4.2 neutralized, spray-dried and, depending on the intended use, with suitable organic acids such as glutaric acid or adipic acid, e hired.

Proent data in the following examples relate to if it is not a question of concentration, the weight of the leather after folding or withering.

Example 4

In the usual manner chrome tanned calfskin be after folding without neutralization short ^it ö PÜlt, sammed and (15 - 25 revolutions / minute) in a high-speed tanning drum drummed for one hour without fleet. Then a solution adjusted to an acid number of 310 with acetic acid of 15 %, that in example 1

The neutral condensation product described in 50 "$> water was added through the hollow axis and drummed for a further 3 hours.

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The leathers are then neutralized and dyed as usual and greased. The achieved ' The shrinking effect can be worked out even more. The leather can be finished both by aniline dressing and by covered dressing.

The leathers obtained in this way are distinguished by uniform shrinkage while having good fullness.

Example 5

Chrome-pretanned bastard skins (wet blues) are rinsed, wilted and drummed for 1 hour in the tanning drum. Thereafter, a solution of 5 * i 98jtiger acetic acid and 25 t of water is added and drummed in for gleichmäesigen distribution in the leather 30 minutes. Added through the hollow axis to the shrinkage .A solution of 15 i "of a neutral condensation product prepared according to Example 1 in 25 # gewwlkt water and for a further 3 hours. It is then neutralized and further processed as indicated in Example 4. Even, finely shrunk leathers with good oil are obtained.

Example 6

Cowhides folded to a thickness of 1.8mm, which have been chrome-tanned as usual, are processed in a fast-moving machine without neutralization

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Tanning barrel (15-25 revolutions / minute) drummed for 30 minutes without liquor. Then $ 25> water and 8.5 # 60? Iiger acetic acid are added and drumming for 30 minutes. Then 15 Ί * of a condensation product described in Example 3 without addition of acid to be added in powder form to the tanning drum and # 25 of water at 35 ⁰ C by the hollow axle added after the start of the pass. After 2 hours of milling, the result is very even shrinkage over the entire surface. The shrink leather obtained in this way is rinsed, neutralized, dyed, greased and either hanging or dried in a warm air barrel. To emphasize the shrinkage, the leather can be peeled after the cleat. The leather can be finished with an aniline finish as well as with a covered finish.

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Claims (5)

1S43571 claims; 1) Process for the preparation of condensation products, thereby characterized in that 1 mol of a diphenyl oxide sulfonic acid is mixed with approximately 0.5-4 mol of an aromatic oxycarboxylic acid, preferably salicylic acid, and approximately 1 to 4 moles of formaldehyde or formaldehyde-releasing agent in an acidic medium condensed. 2) Method according to claim 1, characterized in that the condensation in the pH range below 2.0 at increased Temperature, preferably in the range from 80 ° C to 115 ° C is carried out. 3) Methods of tanning hides and skins and of tanning Pre-tanned leather, characterized in that condensation products are obtained as sole, substitute or retanning agents used according to the procedure of claims 1 and 2. 4) Process for the production of shrink leather, characterized in that that one for the shrinkage tanning condensation products obtained according to the method of claims 1 and 2 used. 5) Condensation products obtained by condensation of 1 mol of a diphenyl oxide sulfonic acid with approximately 0.5-4 mol of a aromatic oxycarboxylic acid, preferably salicylic acid, and approximately 1 to 4 moles of formaldehyde or formaldehyde-releasing agent in an acidic medium. Le A 9889 909831/1396