Classifications

• • C—CHEMISTRY; METALLURGY
  • C14—SKINS; HIDES; PELTS; LEATHER
  • C14C—CHEMICAL TREATMENT OF HIDES, SKINS OR LEATHER, e.g. TANNING, IMPREGNATING, FINISHING; APPARATUS THEREFOR; COMPOSITIONS FOR TANNING
  • C14C9/00—Impregnating leather for preserving, waterproofing, making resistant to heat or similar purposes
  • C14C9/02—Impregnating leather for preserving, waterproofing, making resistant to heat or similar purposes using fatty or oily materials, e.g. fat liquoring

Definitions

• the invention relates to the use of special sulfated substances for greasing leather.
• These substances are reaction products of mono- or polybasic carboxylic acids with 12 to 72 carbon atoms or mixtures of such carboxylic acids with a sulfonating reagent made from at least one organic sulfonic acid and sulfuric acid.
• greasing agents are the most important tools to shape the character of leather.
• the effect of the fatliquoring agents comes about through fiber-insulating lubrication and through hydrophobization.
• the mutual friction is reduced and, consequently, the suppleness and stretchability of the fabric are improved.
• This has positive effects on the tensile strength of the leather, because in a stretchable material, many fibers align in the direction of tension when subjected to tensile stress and then resist tearing more than the same fibers within a brittle material.
• Vegetable and animal oils, fats and waxes are generally used as leather greasing agents, furthermore the hydrolysis, sulfation, oxidation and hardening products obtained from these substances by chemical conversion and finally mineral greasing agents; in detail:
• the saponifiable fats and oils as well as the natural waxes and resins belong to the esters.
• Oils and fats refer to esters of glycerin and fatty acids that are solid or liquid at room temperature.
• For leather greasing from the group of animal fats in particular trane, fish oil, beef tallow and beef claw oil, from the group of vegetable fats castor oil, rape oil and linseed oil are used.
• the fatty acids are esterified with higher molecular weight alcohols instead of glycerin.
• waxes are bees wax, Chinese wax, carnauba wax, montan wax and wool fat; The most important resins include rosin, yeast oil and shellac.
• the chemical conversion of vegetable and animal fats gives products which are water-soluble and which moreover have different emulsifying effects on water-insoluble fatty substances.
• the sulfated water-soluble oils of various types are known, the tears modified by oxidation, which are referred to as degras or moellon, the soaps which are formed during the hydrolytic cleavage of natural fats, hardened fats and finally free fatty acids such as stearic acid as stoving fats.
• Most animal and vegetable fats have a certain affinity for the leather substance, which is considerably increased by the introduction or exposure of hydrophilic groups.
• Mineral greasing agents are also important for leather production. These hydrocarbons are in the natural fats and oils Similar to some properties, but cannot be saponified. These are fractions from petroleum distillation, which are called mineral oil in liquid form, petroleum jelly in pasty form and paraffin in solid form.
• licker oils leather is usually greased with the help of oil-in-water emulsions, the so-called licker oils.
• These liqueur oils are self-cleaning products that contain a neutral oil and an emulsifier in an aqueous medium.
• the emulsifier can either be admixed to the licker oil as a separate component or be produced by partial sulfonation of the neutral oil.
• agents for greasing leather that are produced by this classic and still important process are sulfated claw oil, sulfated lard oil and rapeseed oil, sulfated fish oil and sulfated beef tallow.
• the amounts of concentrated sulfuric acid typically used for the sulfation are typically in the range from 15 to 60% by weight, based on the oil to be sulfated (cf. Hans Herfeld, ed., "Bibliothek des Leders, Frankfurt 1987, Volume 4, page 77-78).
• the classic sulfation process has the disadvantage, however, that it requires complex and time-consuming work-up measures.
• the reason for this is that in practice the fats and oils to be sulfated are brought into contact with - based on these fats and oils - the already mentioned high amounts of concentrated sulfuric acid, for example about 20% by weight in the case of fish oil become. Only a part of the sulfuric acid reacts, the rest - as a rule the majority - is present in unchanged form after the reaction. After neutralization with usually NaOH, a large amount of sodium sulfate is accordingly present. The consequence of this is that the products are not stable in storage. A lack of storage stability means that separation into several phases occurs. The aqueous phase contains a large part of the respective inorganic salts, e.g. As sodium sulfate or ammonium sulfate.
• the purpose of the postprocessing is to remove a large part of the salt. This is usually done by first washing the neutralized sulfation product with water. The (salt-rich) aqueous phase is then separated from the (low-salt) oil phase.
• the phase separation process is difficult to carry out in practice and is time-consuming.
• the wash water that arises is environmentally harmful both with regard to the salt load contained therein and with regard to the (small) amounts of sulfated products contained therein.
• this method should essentially correspond to the method known from IN-A-146 476, in which frog oil is sulfated after ethoxylation, a method which aims to improve the performance properties of sulfated oils, Above all, to improve the resistance to electrolytes by modifying the raw material before sulfonation, which, however, was rather regarded as a curiosity in the relevant specialist literature (cf. Hans Herfeld, ed., "Library of Leather, Frankfurt 1987, Volume 4, page 78, fifth paragraph).
• DE-A-41 41 532 discloses a process for the preparation of hydrophylized triglycerides in which saturated, unsaturated and / or blown triglycerides are first reacted with ethylene oxide in the presence of glycerol and alkaline catalysts, and the resulting ethoxylated triglycerides are reacted with gaseous ones Sulfur trioxide sulfates and the resulting acid sulfonation products then neutralized with aqueous bases. According to the teaching of DE-A-41 41 532, the products thus produced are suitable for greasing leather.
• a very important need in practice is to provide greasy substances or finishing agents which can be bound in the tanned skin substance so reliably that the leather is washable and cleanable enough for practical needs - and fur products is ensured.
• High-quality leather goods for example from the clothing industry, are said to be accessible to both aqueous-surfactant laundry and, if appropriate, chemical cleaning without a significant loss in quality.
• leather that is used in the interior of cars and aircraft to have substances for greasing equipment that are fogging-resistant. “Fogging” means that volatile substances escape from the leather over time and are deposited in an undesirable manner, for example on windshields.
• Fogging-genuine substances are understood to mean that on the one hand these substances are themselves so tightly bound inside the leather that they are practically non-volatile, and on the other hand that these substances improve the fogging characteristics of conventional fat and fat components. ie reduce their fogging values.
• EP-A-498 634 teaches a treatment of the leather with aqueous dispersions which are free from organic solvents and which contain an amphiphilic copolymer which consists of at least one hydrophilic monomer and at least one hydrophobic monomer.
• the object of the present invention was to provide substances which are suitable for greasing leather.
• greying equipment means on the one hand leather greasing in the narrower sense of the word, and also the hydrophobization of leather.
• a further task was that these substances impart good properties with respect to grain strength, fullness, lardiness to the leather treated with it, that is to say, leaked leather, and that subsequently dyed leather are distinguished by an unlightened, level shade.
• Another task was to ensure that these substances are well absorbed by leather and are particularly characterized by a high leach liquor consumption. In addition to its purely technical relevance, the latter point is also useful from an ecological point of view.
• Another task was that the leather treated with these substances had good fogging characteristics.
• the present invention accordingly relates to the use of sulfonated substances for greasing leather, the sulfated substances being obtainable by reacting mono- or polybasic carboxylic acids a) with 12 to 72 carbon atoms, with a sulfonating reagent b) in addition subsequent neutralization.
• a combination of at least one organic sulfonic acid b1) and sulfuric acid b2) is used as the sulfonating reagent b), with the proviso that the proportion of sulfuric acid - based on the sum of organic sulfonic acid and sulfuric acid - 0.5 to Is 80% by weight.
• the invention itself is not subject to any restrictions. Particularly important embodiments are the fatty acids, the dicarboxylic acids and the dimer or trimer fatty acids.
• Fatty acids - as is common in the art are understood to mean all aliphatic, monobasic carboxylic acids that are both saturated and can be unsaturated.
• fatty acids Ren which are suitable as fatty acid building blocks of the esters a
• Dicarboxylic acids are understood to mean dibasic organic carboxylic acids. Preference is given to those with 2 to 24 carbon atoms and in particular those which - in the sense of the classic definition of "Römpp” (see, for example, O.-A.Neumüller, Römpps Chemie-Lexikon, Stuttgart 1973, p .828f) - derived from linear paraffins in that both ends are oxidized to carboxyl groups.
• dicarboxylic acids examples include oxalic acid, malonic acid, succinic acid, glutaric acid, adipic acid, pelic acid, suberic acid, azelaic acid, sebacic acid, dodecanedioic acid, furthermore maleic acid, fumaric acid, phthalic acid and terephthalic acid.
• dicarboxylic acids containing OH groups e.g. Malic acid, preferred.
• Dimer fatty acids - as is customary in the art - are to be understood as those carboxylic acids which are accessible by oligomerizing unsaturated carboxylic acids, generally fatty acids such as oleic acid, linoleic acid, erucic acid and the like.
• the oligomerization is usually carried out at elevated temperature in the presence of a catalyst made of, for example, alumina.
• the products obtained are mixtures of different substances, with the dimersization products predominating. However, are also minor Portions of higher oligomers, in particular "which contain trimer fatty acids.
• Dimer fatty acids are commercially available products and are offered in various compositions and qualities. For the purposes of the present invention, those dimer fatty acids are preferred which have a dimer content of at least 50%, preferably 75% and in which the The number of carbon atoms per dimer molecule is predominantly in the range from 36 to 44.
• trimer fatty acids are oligomerization products of unsaturated fatty acids, but the proportion of trimers in the product predominates. Trimer fatty acids are also commercially available products. Preferred trimer fatty acids are those in which the trimer content is at least 50%, preferably 75%.
• component a) is at least partially ethylenically unsaturated.
• "At least partially ethylenically unsaturated” means that the iodine number of carboxylic acid a) is at least 5.
• the iodine number of the carboxylic acid a) is limited in practice by values in the range from approximately 300 to 400.
• those carboxylic acids or carboxylic acid mixtures a) are generally used whose iodine number is in the range from 40 to 260.
• the choice of the method for determining the iodine number is of minor importance per se. Within the meaning of the present invention, however, express reference is made to the methods according to Hanus or Wijs, which have long been a part of the CV section of the "DGF standard methods", and to the equivalent newer method according to Fiebig (cf. Fat Sei. Technol. 1991, No. 1, pp. 13-19).
• the quantitative ratios of carboxylic acid a) and sulfonating reagent b) can vary within wide limits.
• the proportions of these components are set so that they are in the range from 1:99 to 99: 1.
• a range a): b) from 10: 1 to 1:10 and in particular a range from 4: 1 to 1: 4 is preferred.
• the sulfonated substances according to the invention are very generally characterized by good greasing or hydrophobizing properties and by good fogging characteristics.
• the carboxylic acids a) can be used in the form of commercially available products.
• qualities such as are present, for example, in distillation residues of fatty acid extraction are also sufficient.
• component a) to be sulfonated is used in the form of a mixture of at least one carboxylic acid a) and at least one lower alkyl ester of a fatty acid which is liquid at 20 ° C. and has 8 to 24 carbon atoms.
• a lower alkyl ester is understood to mean that the alcohol building block of the ester has at most 8 carbon atoms, the range from 1 to 4 carbon atoms being preferred.
• the fatty acid lower alkyl ester can be saturated or (ethylenically) unsaturated with respect to its alcohol and / or fatty acid units.
• This embodiment has the advantage that the fatty acid lower alkyl ester has the task of liquefying carboxylic acids a) which are completely or partially solid at 20.degree. C. or at least converting them into a homogeneous and flowable state, so that the mixture - possibly after a slight change Warming - stir gently.
• Another embodiment of the present invention consists in reacting those carboxylic acids a) with the sulfonating reagent b) which are alkoxylated and / or epoxidized.
• Suitable building blocks for alkoxylation are, in particular, ethylene oxide, propylene oxide and butylene oxide or their mixtures.
• ethoxylated fatty acids which are derived formally from the addition of one or more -CH2-CH2-0 groups.
• These compounds can be prepared in various ways, for example by reacting the fatty acids with ethylene oxide in the presence of a catalyst (classic ethoxylation) or by reacting the fatty acids with polyethylene oxide in the presence of a catalyst.
• a combination of at least one organic sulfonic acid b1) and sulfuric acid b2) is used as the sulfonating reagent b); the proportion of sulfuric acid - based on the sum of organic sulfonic acid and sulfuric acid - is 0.5 to 80% by weight. However, a sulfuric acid content of 1 to 40 and in particular 5 to 20% by weight is preferred.
• the sulfonating reagent is not subject to any restrictions with regard to the nature of the sulfuric acid.
• dilute sulfuric acid concentrated sulfuric acid or fuming sulfuric acid (concentrated sulfuric acid, which contains varying amounts of dissolved sulfur trioxide, the so-called oleum) can be used. It is preferred to use sulfuric acid at a concentration in the range from 96 to 98% by weight or oleum.
• organic sulfonic acids b1) are not subject to any particular restrictions.
• suitable sulfonic acids are alkane or haloalkanesulfonic acids such as methanesulfonic acid, ethanesulfonic acid, propanesulfonic acid, butanesulfonic acid, long-chain alkanesulfonic acids, chloro- sulfonic acid, also naphthalenesulfonic acid, alpha-sulfo-fatty acids (obtainable, for example, by reacting saturated fatty acids with gaseous sulfur trioxide), alpha-sulfo-fatty acid alkyl esters, for example methyl ester (obtainable, for example, by reacting saturated fatty acid alkyl esters with gaseous) Sulfur trioxide).
• aromatic sulfonic acids are used as component b2).
• Alkylbenzenesulfonic acids and in particular the commercially available linear alkylbenzenesulfonic acid are particularly preferred.
• the carboxylic acids a) are finally reacted with a sulfonating reagent b) which consists of a ternary combination of at least one organic sulfonic acid b1), sulfuric acid b2) and at least one hydrogen sulfate b3) (older name: bisulfate).
• a sulfonating reagent b) which consists of a ternary combination of at least one organic sulfonic acid b1), sulfuric acid b2) and at least one hydrogen sulfate b3) (older name: bisulfate).
• Suitable hydrogen sulfates are compounds of the structure Alk-HSO j , where "Alk” means a monovalent metal or NH4.
• Preferred monovalent metals are the alkali metals, especially sodium and / or potassium.
• Another object of the present invention is a process for the preparation of sulfated substances, wherein mono- or polybasic carboxylic acids a) having 12 to 72 carbon atoms, with a sulfonating reagent b) are reacted and the reaction mixture is then neutralized, with the conversion is carried out at temperatures in the range from 20 to 130 ° C. and uses a combination of at least one organic sulfonic acid bl) and sulfuric acid b2) as sulfonating reagent b), with the proviso that the proportion of sulfuric acid - based on the sum of organic Sulfonic acid and sulfuric acid - 0.5 to 80 wt .-% is.
• the process according to the invention has the advantage that it generally requires only moderate reaction temperatures.
• the reaction temperature is only in the range from 20 to 80 ° C. and in particular 20 to 40 ° C.
• the reaction proceeds spontaneously with the release of heat after the components a) and b) have been combined, so that in these cases cooling must even be carried out to ensure that the reaction proceeds in a controlled manner.
• reaction times are relatively short, usually of the order of 1 to 4 hours. However, depending on the nature of the component a) used in each case, it may also be desirable to set reaction times below one hour or above 4 hours.
• the process is usually carried out by mixing components a) and b) at about 20 ° C.
• An exothermic reaction often occurs here - particularly strongly in those cases where the sulfonating reagent consists of a mixture of aromatic sulfonic acids and sulfuric acid.
• the reaction mixture is now stirred at a slightly elevated temperature.
• the method according to the invention is carried out at the lowest possible temperature. This is in cases where at 20 ° C liquid carboxylic acids are used as component a) and where the The proportion of sulfuric acid in the sulfonating reagent b) is in the preferred range from 1 to 40% by weight, preferably in the range from 20 to 40 ° C., in which case it is often necessary to cool externally in order to maintain the temperature in this range.
• carboxylic acids a) which are not sufficiently liquid at 20 ° C. or a slightly elevated temperature, or where the reaction is to be brought to an end as quickly as possible, it may be desirable to use the entire temperature range of 20 to 80 ° C. or 20 to 130 ° C. In individual cases it may even be desirable to carry out the reaction at higher temperatures (up to approx. 250 ° C.), e.g. B. if one uses as component a) carboxylic acids with a high melting point, but wants to dispense with the possible addition of a diluent or if the reaction rate is to be increased even further. In the range of these high reaction temperatures, it may be expedient to carry out the reaction in the presence of air in an inert gas atmosphere (for example under nitrogen).
• an inert gas atmosphere for example under nitrogen
• neutralization follows.
• the reaction mixture is allowed to cool and the desired base is then metered in.
• suitable bases are alkali metal hydroxides, alkaline earth metal hydroxides, ammonium hydroxide, alkanolamines and alkylamines or mixtures thereof. Sodium hydroxide, potassium hydroxide and ammonium hydroxide are particularly preferred. Further processing of the neutralized products is not necessary.
• F-l erucic acid (acid number 166; iodine number 75)
• F-2 arachidonic acid (acid number 184, iodine number 334)
• F-5 Oleic fatty acid ("Edenor Ti05", acid number 201; iodine number 95; Fa.
• F-7 Conjuene fatty acid ("Edenor UKD 3510", acid number 198; iodine number 140; Fa.
• F-8 polyunsaturated fatty acid ("Edenor Sj", acid number 201; iodine number 131;
• Alkylbenzenesulfonic acid which is also a commercially available product, is obtainable by sulfonating linear alkylbenzenesulfonate with gaseous sulfur trioxide.
• carboxylic acid e.g. F-1 to F-8
• sulfonating agent e.g. S-1 to S-3
• the mixture is stirred for about 2 hours, a temperature in the range from 20 to 40 ° C. being set. In the case of exothermic reactions, cooling is carried out accordingly.
• carboxylic acids which are solid, partially solid or viscous at 20 ° C. (e.g. carboxylic acid F-6)
• a reaction temperature is chosen in which the carboxylic acid is liquid. If possible, a temperature of at most 80 ° C is set.
• the reaction mixture is then neutralized with a base (for example 37% by weight aqueous sodium hydroxide solution), if appropriate after the mixture has been cooled beforehand.

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• Chemical & Material Sciences (AREA)
• Oil, Petroleum & Natural Gas (AREA)
• Chemical Kinetics & Catalysis (AREA)
• General Chemical & Material Sciences (AREA)
• Organic Chemistry (AREA)
• Treatment And Processing Of Natural Fur Or Leather (AREA)
• Organic Low-Molecular-Weight Compounds And Preparation Thereof (AREA)
• Coloring (AREA)
• Lubricants (AREA)

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• 1994
  • 1994-02-21 DE DE4405416A patent/DE4405416A1/de not_active Withdrawn
• 1995
  • 1995-02-13 WO PCT/EP1995/000511 patent/WO1995022632A1/fr active IP Right Grant
  • 1995-02-13 DE DE59503704T patent/DE59503704D1/de not_active Expired - Fee Related
  • 1995-02-13 EP EP95908273A patent/EP0746630B1/fr not_active Expired - Lifetime
  • 1995-02-13 AT AT95908273T patent/ATE171481T1/de active
  • 1995-02-16 TR TR00156/95A patent/TR28870A/xx unknown

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