DE1932630C3 - Process for impregnating leather to achieve water and oil resistance and leather impregnating agents therefor - Google Patents

Description

B) compounds containing fluorinated lipophilic radicals of chain lengths Cg to Cm from the Group of fluorocarboxylic acids or their esters and fluoroalcohols or their esters, Ether or acetals are used.

2. The method according to claim 1, characterized in that in the solution as a condensation product A) a reaction product of 1 mol of aluminum isopropoxide and 0.7 to 1.5 mol of one Monoalkylphosphoric acid ester mixture of chain lengths Ci2 to Ci8 is used.

3. The method according to claim 1, characterized in that in the solution as compound B) a Mixture of perfluorooctanoic acid and a methacrylic acid ester of a fluorinated unsaturated fatty alcohol mixture the average chain length Cg is used.

4. The method according to claim 1 to 3, characterized in that the proportion of fluorinated Compounds in the active ingredient mixture is about 5 to 90, preferably 10 to 50% by weight.

5. The method according to claim 1 to 4, characterized in that the solvents and diluents used are benzines with a boiling point of 60 to 200 ⁰ C, ethyl acetate, butyl acetate, trichlorethylene or toluene.

6. The method according to claim 1 to 5, characterized in that solutions in organic Solvent with a concentration of 0.5 to 6% by weight, preferably 1 to 4% by weight, of the Sum of compounds A) and B) are used.

7. The method according to claim 1 to 6, characterized in that the impregnation solutions in addition about 1 mole of acetylacetone or ethyl acetoacetate, based on 1 mole of compound A), contain.

8. The method according to claim 1 to 7, characterized in that the impregnation solutions in addition Contain dimethylpolysiloxane.

9. Leather impregnation agent for performing the method according to claim 1, consisting of one Mixture of fluorinated and non-fluorinated compounds as water and oil repellent Component in organic solvents, characterized in that it is water and Oil-repellent component in organic solvents a mixture of

A) Condensation products from aluminum alcoholates of lower monoalcohols of chain lengths Ci to C4 with phosphoric acid monoesters higher fatty alcohols of chain lengths C12 to C 20 and

B) fluorinated lipophilic residues of chain lengths Ce

The invention relates to a method for impregnating leather with organic solutions of Mixtures of fluorochemicals and non-fluorinated compounds with the aim of achieving good water and to achieve oil resistance of the treated leather.

From German patent specification 10 61478 it is known to use condensation products of alcoholates of polyvalent metals and acidic higher molecular weight organic derivatives of phosphoric acids in organic solvents for impregnating leather. The impregnation gives the leather water-repellent properties, with preferably good water-beading effects being achieved and the water absorption of the impregnated leather also being reduced to a greater or lesser extent. At higher use concentrations, however, the leathers become increasingly hardened and darker in color, while the water absorption and dynamic water resistance are only slightly improved.
The use of so-called is also known

jo fluorochemicals for leather impregnation. Below fall saturated or unsaturated fluorocarboxylic acids or fluoroalcohols of chain lengths Cg to Cig and their esters or derivatives and polymerizable fluorine-containing compounds, such as. B. acrylic or Methacrylic acid esters of fluorinated higher alcohols or esters and ethers of allyl alcohol with fluorinated ones higher carboxylic acids or alcohols or acetals of unsaturated aldehydes with fluorinated alcohols etc.

The impregnation with the fluorochemicals mentioned in organic solution gives water and oil-repellent leathers that show good water-repellent and oil-repellent effects. The dynamic water resistance however, it is no better than those impregnated with the phosphoric ester condensation products Leather. With increasing application concentration of the fluorochemicals, the water absorption increases decreased. However, the leather properties change at the same time in an increasingly disadvantageous manner Wise. The leathers become harder and more stained.

In addition, the oil-repellent effect is more and more lost at higher concentrations.

Finally, in DT-OS 14 69 462 impregnating agents for textiles and leather, which are made from a fluorinated polymer, a melamine-formaldehyde condensation product and / or another non-fluorinated diluent polymer in an organic solvent. The means can also contain up to 50% of a wax. The funds are used to make insoluble closed

To form coatings on sensitive surfaces that cannot tolerate water treatment. They are fixed by a heat treatment at temperatures up to 180 ^° C. with reaction with the sensitive surfaces and are said to be water and oil repellent

ft.s cause effects.

The disadvantage of these agents is, on the one hand, that they are a complicated mixture of certain polymers represent that by thermal treatment

must be cured and reacted with the surface of the substrate. They make up as well closed surface coatings that hinder the air permeability of the leather and also the Change surface character.

The object of the invention is to provide better impregnation and better water behavior, in particular to achieve a better dynamic water resistance of the impregnated leather without it the general character of the leather due to hardening, staining or influence on the color shade in an unfavorable way Way changes

The object is achieved with a method for impregnating leather to achieve Water and oil resistance by means of mixtures of fluorinated and non-fluorinated compounds in organic Solvents according to the invention in that an organic solution of

A) Condensation products from aluminum alcoholates of lower monoalcohols of chain lengths Ci to C ₄ with phosphoric acid monoesters of higher fatty alcohols of chain lengths C _{] 2} to C ₂ O and

B) fluorinated lipophilic residues of chain lengths from Cs to C'20-containing compounds from the group of fluorocarboxylic acids or their esters and the Fluoroalcohols or their esters, ethers or acetals are used.

The invention also relates to leather impregnation agents for carrying out such a process, as they are characterized in claim 9.

The surprising finding was made that the combination of the means A) known per se and B) eliminates the disadvantages which occur when using the two impregnating agents separately. It a better thorough impregnation and a significantly better water behavior of the impregnated Leather is achieved without the general leather character being affected by hardening, staining or influencing the color tone and the like adversely changes. Another advantage is that the application concentration of Active ingredient solutions can be increased significantly, resulting in further improvements in terms of Water and oil repellent effects as well as the dynamic water resistance of the impregnated leather without significant A change in the character of the leather can be achieved.

The condensation products according to A) are according to German patent 10 61 478 by reaction of aluminum alcoholates, e.g. B. aluminum isopropoxide or butoxide, with phosphoric acid monoesters higher Obtain fatty alcohols with 12 to 20 carbon atoms. The formation takes place in such a way that one dissolves the Starting components in an organic solvent such as isopropanol, trichlorethylene or toluene combines and, if necessary, heated to temperatures of about 30 to 50 ° C for a short time.

The molar ratio of alcoholate to phosphoric acid ester should be about 1: 0.5 to 1.5. Up to 30 mol percent of the phosphoric acid monoester can be replaced by corresponding phosphoric acid diesters of higher fatty alcohols. Suitable products of group A) are the reaction product of 1 Mo! Aluminum isopropylate with 0.7 mol of a monoalkyl phosphoric acid ester with alkyl radicals C'12 to Ci ₈ , the reaction product of 1 mol of aluminum propylate with 0.9 mol of the monotetradecyl phosphoric acid ester, the reaction product of 1 mol of aluminum butylate with 0.6 mol of a monoalkyl phosphoric acid ester with alkyl radicals Ci ₆ to Ci ₈ . Compounds containing enol groups, such as acetylacetone or ethyl acetoacetate, can be added to the solutions of these products to stabilize them against the effects of moisture.

The compounds of group B) contain a lipophilic fluorinated one as a common feature Hydrocarbon radical with chain lengths from Cs to C'20 · Es are also known compounds from the group of higher saturated or unsaturated fluorocarboxylic acids and their esters with lower saturated or unsaturated alcohols, preferably allyl alcohol, as well as from the group of the higher saturated or unsaturated or branched chain Fluoroalcohols and their esters, ethers or acetals with lower, preferably unsaturated ones Carboxylic acids, alcohols or aldehydes. Examples of compounds of group B) are: perfluorodecanoic acid, a mixture of perfluorinated carboxylic acids of chain lengths Ci2 to Cw, perfluorooctanoic acid allyl ester, perfluorododecyl alcohol, Perlluorododecyl alcohol acrylic acid ester, a mixture of the methacrylic acid esters perfluorinated Fatty alcohols with chain lengths from C12 to C'i », perfluorodecanol-formaldehyde acetal. To the extent that the aforementioned compounds are esters of acrylic or methacrylic acid or esters or ethers of Allyl alcohol acts, the compounds are polymerizable and can also be in the form of their soluble Polymers or copolymers are used. The proportion of fluorinated compounds in the active ingredient mixture can be about 5 to 90, preferably 10 to 50 wt .-%. It can already be done with relatively low proportions of fluorine compounds in the mixture achieve very beneficial effects, so that the claimed Method is also particularly advantageous from an economic point of view.

J5 The compounds A) and B) used in the process according to the invention are in organic solution in concentrations of about 0.5 to 6% by weight, preferably 1 to 4% by weight, based on the sum of components A) and B) applied. Suitable solvents and diluents mainly gasolines come 60 to 200 ⁰ C, ethyl acetate, butyl acetate, chlorinated hydrocarbons such as methylene chloride, methyl chloroform, trichlorethylene, perchlorethylene or toluene, etc. boiling limits. And preferably mixtures of mineral spirits of boiling range 60 to 95 ° C and ethyl acetate into consideration.

The leather is treated by dipping, but mainly by spraying onto the leather surface. The leathers are expediently treated in a dry state. After impregnation post-drying takes place at 50 to 70 ° C., if necessary in the presence of humidity, which means that optimum water resistance is achieved immediately. Cheap Effects can also be achieved by post-drying at room temperature, but this is necessary Method a storage time of a few days.

Particularly suitable for the impregnation process according to the invention are types of suede, such as shoe and clothing suede, but also unfinished or poorly finished, so-called aniline leather types.

The leather impregnating agents used in the process according to the invention from the specified combinations of active ingredients can contain other conventional additives, such as waxes, resins or dyes, in order to achieve a

<> 5 different types of leather are cheap To achieve influencing of the leather character. To further increase the water resistance, commercially available Silicone oils based on dimethylpoly-

siloxanes or methyl hydrogen polysiloxanes are also used.

Examples

There are stock solutions of an aluminum alcoholate-phosphoric acid ester condensation product ("Solution A") and a mixture of fluorinated compounds ("Solution B"), from which by mixing and further diluting the impregnation solutions of the following examples can be obtained.

Solution a

216 parts by weight of aluminum isopropylate are dissolved in 240 parts by weight of perchlorethylene with heating and with a solution of 200 parts by weight of a monoalkylphosphoric acid ester mixture of chain lengths C12 to C'i8 in 200 parts by weight of perchlorethylene with stirring and heating to 65 to 70 ⁰ C gradually united to the clear reaction mixture dissolved 144 parts by weight of ethyl acetoacetate are added with stirring and stirred for another two hours at about 70 ⁰ C. The solution contains about 40% by weight

Aluminum alcoholate-phosphoric acid ester condensation product.

Solution b

There are 4.5 parts by weight of a mixture of about 1 part by weight of perfluorooctanoic acid and about 2 parts by weight of the methacrylic acid ester of a fluorinated unsaturated fatty alcohol mixture of the average chain length Ce dissolved in methyl chloroform.

example 1

32 parts by weight of solution A are mixed with 40 parts by weight of solution B. The yellow-colored, clear Imprägniermitlelgemisch is ⁰ to 140 C and 7 parts by weight of butyl acetate diluted with a further 21 parts by weight of gasoline boiling range of the 110th The resulting 15% active ingredient solution is further diluted for use with petrol with a boiling point of 60 to 95 ° C or ethyl acetate to an active ingredient content of 1 or 4% by weight.

Table 1

A commercially available, slightly retanned and greased chrome cowhide leather of the so-called aniline leather type is sprayed with a 10% or 4% active ingredient solution of the aforementioned impregnating agent mixture so that in the first case about 2.5 g / m ² leather surface and in the second case about 9 g / .ti ² leather surface can be applied. After the leather has dried and deposited, those in the table! received impregnation data contained. At the same time, the table contains data which were obtained with solution A or with solution B after appropriate dilution or with a dimethylpoiysiloxane solution of the appropriate concentration or with untreated leather.

The result clearly shows that with the impregnating agents according to the invention without any disadvantageous change the leather character significantly better impregnation effects can be obtained than with the individual components or with the commercially available dimethylpolysiloxane.

Example 2

28 parts by weight of solution A are mixed with 36 parts by weight of solution B and 4 parts by weight of a commercially available dimethylpolysiloxane with gentle heating. The mixture is diluted with 28 parts by weight of butyl acetate and 4 parts by weight of perchlorethylene. The result is an approximately 17 wt ° / o active compound-containing impregnating agent which is further diluted with gasoline boiling range of ⁰ to 95 C, or ethyl acetate at a content of active substance 60 of about 1 to 4 wt .-% for the application.

The same as used in Example 1, commercially available, slightly retanned and greased chrome cowhide leather upper of the aniline leather type is - as described in Example 1 - with the above impregnating agent mixture treated and finished. The impregnation data can also be found in Table I. Im Compared to the individual components is despite the relatively small amount of fluorine compounds obtained a superior overall effect in the impregnating agent mixture.

Applied
Concentralization
related to
Effective Drip bottle
Water machine oil l'enetro-
mclcr-TcM:
Water-
dii ichtiitt
in min. ¹ ) % Watercrawl
according to K 11 be I k a
after
30 '2 ¹ ' 24 '' 59.8
54.7 80.3
79.1 lieiirlciliing dos
Leather example 1 1%
40/0 40 '40' 12 '
25 ' 46.1
42.8 68.5
64.0 88.1
81.9 good grip
a bit cheesier
as 1% active ingredient Example 2 1%
40/0 > l ^h 25 '
>) !,> 24h 5 '
15 ' 55.5
53.4 70.9
60.1 87.1
82.3 good grip
a bit cheesier
as 1% active ingredient Solution b 1%
40/0 >jh> 24 ^h
30 'no effect
at too high
concentration 6 '
12 ' 58.1
46.9 72.3 93.1 Leather a little harder
Leather hard and
unsightly,
blotchy Dimethyl
siloxane 4% >, h T 60.2 64.1 81.7 no change
opposite to
untreated Solve A 4% > l ^h - 12 ' 56.0 Ship tends to

continuation Applied
concentration
related to
Active ingredient Drop test
Water machine oil Penetro
meter test:
water
passes through
in min. ¹ ) % Water absorption
According to K ubc 1 ka
after
30 '2 ^h 24 ^h Assessment of the
Leather - 4 '- 2 ' 115.4 119.0 131.0 Aniline
character Untreated
leather

') Average value from 3 determinations.

Example 3

30 parts by weight of solution A are mixed with 6ö parts by weight of solution B and with 10 parts by weight of butyl acetate diluted. The yellow-colored, clear impregnating agent solution contains an active ingredient content of about 15% by weight.

As described in Example 1, a commercially available velor leather from cattle slits in dry state with a 10% or 4% active ingredient solution, which can be obtained by diluting the aforementioned Solution obtained with gasoline with a boiling point of 60 to 95 ° C or ethyl acetate is sprayed. After Drying and depositing the leather could produce a superior impregnation effect of the invention Mixture against the individual components can be determined, as Table II shows no adverse change in the character of the leather was observed

Example 4

Part by weight of solution A is mixed with 36 parts by weight of solution B and 4 parts by weight of dimethylpolysiloxane, 28 Parts by weight of butyl acetate and 4 parts by weight of perchlorethylene are added with gentle heating.

A yellow-colored, clear impregnant solution with an active ingredient content of about 17% by weight is obtained. A commercially available suede for clothing as used in Example 3 is given a 1 or 4 % By weight of the adjusted active ingredient solution of the above impregnating agent as described in Example 1, overspray

After the leather was dried and deposited, a became superior to the individual components Impregnation effect obtained without the leather character was adversely changed, as from the Table II can be seen.

Table II

Applied Drop test Penetro ° / o water absorption Assessment of the concentration meter test: according to K u b e I k a Leather related to Water- Active ingredient passes through after Water machine oil in min. ¹ ) 30 '2 ^h 24 ^h

Example 3 1%

Example 4

Solution b

Dimethylsiloxane

4%
1%

4%

1%
4%

4%

10 '

> 24 ^h 5 '

> 24 ^h

30 '

Solution A 4%

Untreated -
leather

90.3 96.4 103.1

57.4
101.5

71.4
107.8

87.1
116.0

32.9 56.1 85.0

> 24h 6 '

no effect 12 'if the concentration is too high

107.8
65.2

126.8

91.7

122.8
80.0

1403
122.9

132.0
100.5

148.1

134.0

137.5 142.1 148.4

no change

opposite to

untreated

no change

opposite to
untreated no differences compared to
untreated no differences

Leather a little harder Leather hard and unsightly, stained

no change

opposite to

untreated

Grind tends to be fat, leather rougher and harder

Velvety, dry leather

·) Average value from 3 determinations.

Claims (1)

Patent claims: 1. Process for impregnating leather to achieve water and oil resistance by means of Mixtures of fluorinated and non-fluorinated Compounds in organic solvents, characterized in that an organic Solution of A) Condensation products of aluminum alcoholates of lower monoalcohols of chain lengths Ci to C.4 with phosphoric acid monoesters of higher fatty alcohols of chain lengths C _t 2 to C'20 containing compounds from the group of fluorocarboxylic acids or their esters and fluoroalcohols or their esters, ethers or acetals
contains