HRP930646A2 - Leather greasing material - Google Patents

Description

Through oiling, the skin acquires several more important properties for use. In particular, it has a lot of influence on: elasticity, hardness, toughness, extensibility, absorption capacity, i.e. resistance to water and air permeability.

Common means for greasing and auxiliary means for greasing the skin are made on the basis of animal oils, such as fish oil, and/or vegetable oils, such as sunflower oil. Since the fats themselves are difficult to apply and do not have the ability to penetrate deeply into the skin, they should be converted into water-emulsifying fatty substances by chemical modification.

These first lubricants, also called "Licker", consist of emulsified fat and a suitable emulsifier. The usual possibility for obtaining "Licker" is oxidation, and later sulfiting of fat.

Both the procedure and the resulting means for oiling the skin are subject to certain requirements, especially on the part of the user. Considering the procedure, the oxidation of the applied oils should be as complete as possible, and the duration of the oxidation should be as short as possible. In order to shorten the oxidation time, it was common until now to use metal catalysts, such as cobalt-naphthenate, zinc-sulfate, aluminum-sulfate or sodium-oxalate.

As catalysts were used, the oxidation often lasted several days.

After the oxysulfite treatment, skin creams often showed disadvantages, such as too high viscosity, especially at low temperatures, an unpleasant fishy smell and too little stability towards chromium. In order to reduce the smell, usually inorganic peroxides were used, as well as hydrogen peroxide (DD-A-21 46 28).

As the aforementioned improvement measures were taken, there was, as before, a desire for thickening agents, which would be expressed in order to improve the properties for use, especially in the field of leather processing.

The task of this invention was to make available such a process for the production of lubricating compositions of oxysulfitated oils of animal and/or plant origin, which requires shorter time periods for oxidation compared to known oxysulfitated processes and which does not require the use of metal catalysts and substances to reduce odors like Xerox.

A further task of the invention was to make available compounds based on oxysulfated oils of animal and/or plant origin, which show improved properties in use compared to known lubricants, such as low viscosity, especially at lower temperatures, less inherent smell, better penetration and improved stability according to oxidizing compounds.

It was shown in a surprising way, that the application of conjugated unsaturated carbonic acids and/or esters achieved the desired improvement.

The subject of the invention is a process for the production of lubricating compositions, which includes:

Oxidation of the composition based on fatty substances containing:

a) 70-99 wt.% fatty substances of animal and/or vegetable origin and

b) 30-1 wt.% of compounds of formula I

[image]

which differ from the compounds of component a) and where R1, R2, R3 are independently branched or straight-chain, in the given case, substituted C1-24 alkyl residues

R4 hydrogen or straight chain or branched,

in the given case a substituted C1-6 alkyl residue

m is an integer greater than zero and

n is an integer greater than zero,

at a temperature above 40°C, preferably in the range of 40 to 90°C, especially preferably 50 to 80°C,

in the given case, the conversion of oxidized fatty substances with 10 to 40 wt.% aqueous alkali hydroxide solution and

by subsequent sulfiting with the addition of 5 to 50 wt.% - preferably 20 to 40 wt.% - of a solution of a sulfited agent under simultaneous or subsequent heating.

Also, the subject of the invention is the masking compounds that can be obtained through the process, which includes the measures mentioned above.

First of all, the procedure for the production of lubricating compositions according to the invention will be explained and, following on from this, the compositions of the same according to the invention.

Compositions based on fatty substances of animal and/or vegetable origin (component a) serve as starting materials for the production of lubricating compositions according to the invention. Examples of fatty substances of animal origin are fish oil, fish oil and its conversion products, beef hoof oil, sperm oil, jaina oil and tallow. Fish oil and beef hoof oil are preferred.

In addition to fats of animal origin, vegetable fats can also be used as starting materials. Examples of fatty substances of vegetable origin are castor oil, rapeseed oil, olive oil, soybean oil, sunflower oil, palm oil, peanut oil, cottonseed oil and linseed oil. Rapeseed oil and sunflower oil are preferred.

The listed fatty substances of animal and vegetable origin can be used individually or in mixtures in the process according to the invention.

If only fatty substances of animal or vegetable origin are used as starting materials for the production of the fattening composition according to the invention, so that their share amounts to 70-90% by weight in relation to the total weight of the mixture. If mixtures of fatty substances of animal and plant origin are used, so that it has starting substances in the composition in a ratio between 30 and 99.9 wt. % fat of animal origin and 70 to 0.1 wt.% of vegetable fat in relation to the total weight of the used fats. One preferred composition consists of approximately equal parts of fish oil, beef hoof oil and canola oil.

In addition to the mentioned fats (component a), they enter as further starting substances of compounds of formula I

[image]

included as components b) which differ from the compounds of component a) and where R1, R2, R3 are independent straight-chain or branched C1-C24 alkyl residues substituted in the given case, preferably straight-chain substituted C16-C20 alkyl residues in the given case, R4 is either hydrogen or a straight-chain or branched, optionally substituted C1-C6 alkyl residue, m is an integer greater than zero, preferably 1 to 5, particularly preferably 1 and n is an integer greater than zero, preferably 1 to 20. Suitable Substituents are for example OH, OR, NH2, NHR1, NHR12, halogen.

Compounds of formula II are preferred

[image]

inserted as component b) which differ from the compounds of component a) and where R1, R2, R3, R4, m and n have the aforementioned meaning.

Further suitable starting materials (component C) assume compounds of formula III

[image]

which differ from compounds components a) and b) and where R5 is a straight-chain and branched, in the given case OH-substituted C9-C24 - alkyl, C9-C24- alkenyl or C9-C24 - alkdienyl residue and that R4 has the aforementioned meaning . These compounds of formula III are contained in a given case in an amount of up to 30% by weight in relation to the entire weight of the mixture.

Especially preferred use as components b) and c) are lauric acid, palmitic acid, stearic acid, margaric acid, 10-methyl-stearic acid, oleic acid, linoleic acid, conjugated linoleic acid, lindenic acid and its esters. Compounds of formulas I, II and in the given case III can be used as individual substances or in the form of mixtures of two or more individual substances. Additional substances can be added to the compositions according to the invention in order to regulate the final alignment, e.g. alkanolamines, such as diethanolamine for an optimal pH value, hydrocarbons, such as paraffin oil, for the desired viscosity, low-molecular mineral oil or synthetic oil, based on chlorinated or otherwise modified paraffin derivatives, as well as softeners, such as glycerin.

These additional substances are preferably added after obtaining the lubricating compositions.

The starting materials found in a suitable reactor are subjected to oxidation at a temperature above 40°C, preferably in the range of 40 to 90°C, and especially preferably 50 to 80°C. Oxidation is preferably followed by introducing a directed stream of air at a rate of 203 to 400 1/h into the mixture.

The final point of oxidation will be indicated by sufficient sulfiting ability of the oxidized lubricant. For this purpose, it is taken from the reaction batch during sample oxidation and sulfited as described. Satisfactory sulphiting ability should be understood as the fact that when this oxysulphated sample is added, preferably 10% by weight, to water, a fine emulsion is formed, which is stable over a period of at least one day at room temperature and which has stability to chromium for at least 5 hours. It has been shown that the final point of oxidation, and thus these properties, is reached mostly 10 to 30 hours earlier than with known procedures.

Following on from oxidation and prior to sulfiting, the conversion of oxidized fatty substances with 10 to 40% by weight, preferably 20 to 30% by weight, of an aqueous solution of a strong base, such as alkali hydroxide, can follow.

For the purpose of sulfiting, oxidized substances are mixed with a solution of a sulfiting agent. The preferred sulfiting agent is an aqueous solution such as sodium pyrosulfite, sodium hydrogen sulfite or dark trioxide. The concentration of aqueous solutions lies in the range between 5 to 50 wt.%. preferably 20 to 40 wt.%.

During the addition of the sulphited agent, the reaction mixture is heated. Usually, the reaction mixture is heated to the boiling point. The reaction mixture is heated until the sample taken does not meet the desired requirements in terms of appearance, ability to emulsify in water and electrolytic stability, especially stability for chromium. The sample must be clear when taken, i.e., transparent and without coloration. Regarding the ability to emulsify in water, the sample must form a stable, finely divided emulsion. These requirements are assessed by observation. Chromium stability in the test must exist over a time interval of more than 5 hours, preferably at least 10 hours.

Chromium stability of oxysulfitated lubricants is tested in the following way. Disperse 5 ml of the oxysulphated sample in 90 ml of distilled water in a 100 ml measuring cylinder. 5 ml of an aqueous chromium sulfate solution is added to this dispersion with vigorous shaking. Chromium sulfate solution is made from 56 g of basic chromium sulfate of the formula Cr(OH)SO4xnH2O with 25 wt.% Cr2O3. The time until phase separation occurs is a measure of chromium stability.

Some additional treatment of oxidized starting materials by washing and/or neutralization in the process according to the subject invention is not necessary, so that the entire sequence of reactions can take place in the same reactor.

The following are the advantages of the method according to the invention:

- shorter times for oxidation compared to usual procedures

- the use of metal catalysts is not required

- it is not necessary to use peroxide.

The following are the advantages of the lubricating composition according to the invention:

- almost odorless product

- low viscosity, partially capable of casting even at 0°C

- high stability to chromium

- application-technical properties similar to products based only on fish oil.

The greasing compositions according to the invention are suitable as highly emulsifying, electrolytically stable greasing agents, excellent for greasing demanding game fur products, shoe leather, velor, furniture, gloves as well as fine top leathers, and are used with great advantages for pre-greasing and smearing after washing. Oiled skin has good tactility and fullness in tight, tight scars.

The degreasing agents according to the invention are suitable extraordinary agents for degreasing the skin. It has been shown that the products penetrate well into the skin and provide a soft, light but full grip.

Examples

Example 1

In a 2 1-reactor, 323 g of fish oil, 337 g of safflower oil, 300 g of rapeseed oil and 40 g of ®Prifac-acid 8968 (manufacturer: Unichema, Che.mie GmbH, DE) were oxidized at 70°C with oxygen from air ( speed: 340 l/h). After 40 hours, the mixture had a viscosity of 3 minutes 30 seconds, measured with "Ford glass" no. 2 at 27°C. After the end of the oxidation, 25.6 g of a 30% by weight aqueous NaOH solution was added with stirring at a temperature of 40°C. The solution is stirred for 30 minutes, at the temperature that occurred during the heat of reaction. Then, 280 g of a 35% by weight Na2S2O5 solution were added successively in equal portions. After the addition of the first half of the Na2S2O5 solution, the mixture is mixed for 15 minutes at the temperature that was formed during the heat of reaction. After the addition of the second half is complete, the temperature is raised to the boiling point. The viscosity of the final product is 10 minutes and 30 seconds as measured with "Ford glass" no. 2 at 27°C.

Chromium stability is given over a time interval of more than 5 hours.

Composition of Prifac acid 8968

23% C18 - carbonic acids (monounsaturated)

9% C18 - carbonic acids (double unsaturated)

50% C18- carbonic acid (conjugated unsaturated)

1% C18 - carbonic acids (triple unsaturated)

1% C18 - carbonic acid

Example 2

The conversion of 323 g of fish oil, 337 g of rapeseed oil and 300 g of rapeseed oil and 40 ®Prifac-acid 8961 is carried out analogously to example 1. After 60 hours, the mixture has a viscosity of 6 minutes 10 seconds measured with "Ford glass" no. 2 at 27°C. The sulfiting is carried out analogously to example 1. The viscosity of the final product is 18 minutes 25 seconds measured with "Ford glass" no. 2 at 27°C. Chromium stability is given over a time period of more than 5 hours.

Composition of ®Prifac-acid 8961

3% C18 - carbonic acid

1% C18 - carbonic acid

25% C18 _ carbonic acids (monounsaturated)

67% C18 - carbonic acids (double unsaturated)

1% C18 - carbonic acids (triple unsaturated)

Claims (11)

1. An agent for degreasing the skin in which the production process is indicated by the oxidation of the composition containing fat, namely 70 to 99% by weight of animal and/or vegetable fat and 30 to 1% by weight of compounds according to formula I [image] which differ from the first mentioned compounds and in which R1, R2, R3 independently of each other are branched or straight-chain substituted C1-24 alkyl residues in the given case, R4 is hydrogen or straight-chain or branched, in the given case substituted C1-6 alkyl residue m is an integer greater than zero and n is an integer greater than zero at temperatures above 40°C, in the given case of conversion of oxidized fatty substances with 10 to 40% wt. proportion of aqueous alkali hydroxide solution and subsequent sulfiting with the addition of 5 to 50% by weight. proportion of the solution of some sulphited agent during simultaneous or subsequent heating. 2. The method according to claim 1, characterized in that the composition is oxidized with an additive containing up to 30% by weight of compounds of formula III where: R5 – COO – R4 which differ from the compounds of the previous components where R5 is straight-chain or branched, in the given case OH-substituted C9-C24 - alkyl or C9-C24 -alkenyl or C9-C24 -alkedienyl residue, and R4 has the meaning specified in claim 1. 3. The method according to claims 1 and 2, characterized by the use of compositions containing: 30 - 99.9 wt.% fat of animal origin and 70 - 0.01 wt.% vegetable fat in relation to the total weight of the used fats, for the components first listed in claim 1. 4. The method according to one of claims 1 to 3, characterized by the fact that the compositions contain equal parts by weight of fish oil, oil from papaya and rapeseed oil in the components first mentioned in claim 1. 5. The method according to one of claims 1 to 4, characterized in that compounds of formula II are used [image] as a component else specified in claim 1, where R1, R2, R3, R4. , m and n specified in claim 1 and which differs from the compounds of the component first specified in claim 1. 6. The method according to one of claims 1 to 5, indicated by the fact that the compounds of the components mentioned in claim 1 are used, where m is an integer from 1 to 5, preferably 1 and n is an integer from 1 to 20. 7. The method according to one of claims 1 to 6, indicated by the fact that the compounds of the components mentioned in claim 1 are used, where R1, R2 and R3 are independent of each other, one straight chain in the given case substituted - C16-C20-alkyl residue. 8. The method according to one of claims 1 to 7, characterized in that the oxidation takes place via the introduction of an air stream at a temperature in the range of 40 to 90°C, preferably 50 to 80°C. 9. The method according to one of claims 1 to 8, characterized in that an aqueous solution of Na2S2O5, sodium hydrogen sulphite or sulfur trioxide is used as a sulfiting agent. 10. Lubricating compositions, characterized by the fact that they can be obtained through the process covered by one of claims 1 to 9. 11. Application of lubricating composition according to claim 10, characterized in that it is used as an agent for greasing the skin.