EP0506751A1

EP0506751A1 - Use of a combination of non-ionic surface-active agents.

Info

Publication number: EP0506751A1
Application number: EP91901279A
Authority: EP
Inventors: Juergen Geke; Bernd Stedry; Raina Hirthe
Original assignee: Henkel AG and Co KGaA
Current assignee: Henkel AG and Co KGaA
Priority date: 1989-12-22
Filing date: 1990-12-13
Publication date: 1992-10-07
Anticipated expiration: 2010-12-13
Also published as: DE59006082D1; PT96342A; EP0506751B1; DE3942727A1; BR9007941A; CA2072009A1; ES2055582T3; JPH05502259A; WO1991009925A3; WO1991009925A2; ATE106937T1; ZA9010356B; DK0506751T3; TR25486A

Abstract

The invention concerns the use, for cleaning hard surfaces, of a combination of non-ionic surface-active agents, the combination containing: (a) at least one alk(en)yl ethoxylate of general formula (I): R<1>-O-(CH2CH2O)n-H, in which R<1> is a straight-chain or branched-chain alkyl or alkenyl group with 6-18 C-atoms or a cyclic alkyl group with 5-6 C-atoms, and n is a number in the range from 2 to 12, and (b) at least one alk(en)yl ethoxylate propoxylate of general formula (II): R<2>-O-(CH2CH2O)p-A-H, in which R<2> is a straight-chain or branched-chain alkyl or alkenyl group with 6-18 C-atoms or a cyclic alkyl group with 5-6 C-atoms, p is a number in the range 2 to 10 and A is a group of the type -(CH2-CH(CH3)-O)q- or -(CH(CH3)-CH2-O)r-, the sum q + r being a number in the range from 2 to 8, the ratio by weight of components a and b being in the range from 10:1 to 1:10.

Description

Use a combination of nonionic surfactants

The present invention relates to the use of a combination of nonionic surfactants - optionally with conventional additives for cleaning hard surfaces. So-called "industrial cleaners" are usually used for such tasks.

Such industrial cleaners are mainly used in the automotive industry and their supplier industries for cleaning and passivation, predominantly in spray cleaning systems. They are suitable for intermediate and final cleaning without cutting as well as machined parts in unit and assembly plants. Practically all relevant materials such as iron and steel, aluminum, silu en, copper, brass, zinc and plastics can be treated and the majority of all contaminations on an organic or inorganic basis, such as cooling lubricants, rust protection oils, processing oils, drawing aids, Pigments and slight metal abrasion can be removed. Such cleaning agents can also be used in customary immersion processes, but their use in the spraying process is usually preferred.

The chemical basic components of such industrial cleaners are usually surfactants and organic corrosion inhibitors. The latter ensure temporary protection against corrosion during and after treatment. In addition, cleaning agents of this type generally contain substances which are able to wanted to counteract foam development. The use of such foam-inhibiting additives is in most cases due to the fact that the contaminants detached from the substrates and accumulating in the cleaning baths act as foaming agents. In addition, the use of so-called anti-foaming agents may also be necessary due to the fact that the cleaning agents themselves contain constituents which give rise to undesired foaming under the given working conditions - ie in particular in the case of spraying processes, for example anionic surfactants or in the case of non-ionic surfactants foaming at the respective working temperature.

From "Ull ann's Encyclopedia of Industrial Chemistry", 4th edition, volume 22 (1982), pages 489 to 493, the use of fatty alcohol polyethylene glycol ethers - also known as fatty alcohol ethoxylates - as surfactant components in detergents and cleaning agents known. However, such addition products of ethylene oxide with fatty alcohols are not suitable for use in spraying processes, since they foam strongly at application temperatures in the range from 15 to 80.degree. It is also known to use fatty alcohol ethoxylate propoxylates as low-foaming wash raw materials; see. for example the Ull ann volume cited above, page 494.

In contrast, the present invention was based on the object of providing surfactant combinations for cleaning hard surfaces which exhibit low-foaming properties in the entire temperature range relevant to the application, namely in the range from 15 to 80 ° C., and thus for use are suitable in spraying processes. In addition, these surfactant combinations should have a high cleaning ability and excellent wetting properties compared to the substrates treated with them; further should these surfactant combinations can be easily assembled with additives customary in industrial cleaners, good, spot-free drainage of the cleaning agent solutions from the treated substrate

Enable surfaces and have demulsifying properties with regard to non-self-emulsifying oils and fats.

Surprisingly, it has been found that mixtures of the nonionic surfactants listed above fully meet the requirements described in the above task over a wide range of mixtures.

The present invention thus relates to the use of a combination of nonionic surfactants, comprising:

(a) at least one alk (en) yl ethoxylate of the general formula (I)

R ¹ -0- (CH ₂ CH ₂ 0) _n -H (I)

in which R - is a linear or branched alkyl radical or alkenyl radical having 6 to 18 carbon atoms or a cyclic alkyl radical having 5 to 6 carbon atoms and n is a number in the range from 2 to 12, and

(b) at least one alk (en) yl ethoxylate propoxylate of the general formula (II)

R ² -0- (CH ₂ CH ₂ 0) _p -AH (II)

in which R ^{2 is} a linear or branched alkyl radical or alkenyl radical having 6 to 18 carbon atoms or a cyclic alkyl radical having 5 to 6 carbon atoms, p is a number in the range from 2 to 10 and A radicals of the type - (CH ₂ -CH (CH3) -0) _q - and - (CH (CH3) -CH ₂ -0) _r - mean- ten, the sum (q + r) being a number in the range from 2 to 8, the weight ratio of components a: b being in the range from 10: 1 to 1:10, for cleaning hard surfaces.

With regard to the surfactant components a and b to be used according to the invention, the following applies in detail:

In the general formula (I) of components a mentioned above, R * - * represents a linear or branched alkyl radical or alkenyl radical having 6 to 18 carbon atoms. The following radicals are suitable as substituents R - *: n-hexyl, n-heptyl, n-octyl, n-nonyl, n-decyl, n-undecyl, n-dodecyl, n-tridecyl, n-tetradecyl, n-pentadecyl, n-.hexadecyl, n-heptadecyl and n-octadecyl and the branched isomers of the alkyl radicals mentioned. Instead of the saturated alkyl radicals, R ** - can also mean the unsaturated alkyl radicals (alkenyl radicals) with a number of carbon atoms in the above range, which can likewise be linear or branched. Furthermore, R ^{1 can} also be a cyclic alkyl radical having 5 to 6 carbon atoms, ie cyclopentyl or cyclohexyl. The number of ethoxy residues in the molecule - index n - is in the range from 2 to 12.

For the purposes of the invention, preference is given to using, as component a, those compounds of the general formula (I) in which R ^{1 is} a linear alkyl radical or alkenyl radical having 6 to 18 carbon atoms and n is a number in the range from 2 to 10. According to a particularly preferred embodiment of the present invention, the reaction product of octanol (R ¹ = linear alkyl radical having 8 carbon atoms) with 4 moles of ethylene oxide is used as the surfactant component a. For the preparation of compounds of general formula (I), reference is made, for example, to the Ullmann monograph cited above

<pointed. Products of this type are also commercially available, for example under the brand name DEHYD0L ^R (Henkel KGaA, Düsseldorf).

In the abovementioned general formula (II) of the surfactant components b, R ^{2 represents} a linear or branched alkyl radical or alkenyl radical having 6 to 18 carbon atoms or a cyclic alkyl radical having 5 to 6 carbon atoms. Suitable substituents R ² are therefore all those radicals which have already been explained above in connection with the substituent R of the general formula (I). The number of ethoxy radicals in the molecule - index p - is in the range from 2 to 10. The substituent A in the general formula (II) stands for propoxy radicals, the number of propoxy radicals - index (q + r) - in the range from 2 to 8.

For the purposes of the invention, those compounds of the general formula (II) are preferably used as component b in which R ^{2 is} a linear alkyl radical having 8 to 18 carbon atoms, p is a number in the range from 2 to 5 and A is propoxy radicals, and the Sum (q + r) is a number in the range 4 to 6. According to a particularly preferred embodiment of the present invention, the surfactant components b used are the reaction product of technical lauryl alcohol - which has alkyl radicals with 12 to 18 carbon atoms (therefore approx. 80% with 12 to 14 carbon atoms) with 2 to 4 moles of ethylene oxide and 4 to 6 moles of propylene oxide or the reaction product of n-octanol with 2 to 6 moles of ethylene oxide and 2 to 5 moles of propylene oxide.

For the preparation of compounds of the general formula (II), reference is also made, for example, to the Ullmann monograph cited above. Such products are also commercially available holds! I, for example under the brand name DEHYPON ^ -LS or -LT (Henkel KGaA, Düsseldorf).

Depending on the area of use and intended use, further nonionic surfactants can be added to the surfactant combinations to be used according to the invention. According to a further preferred embodiment of the present invention, the surfactant combinations to be used according to the invention contain, as an additional component, at least one alk (en) yl ethoxylate mixed ether of the general formula

(III)

R ³ -0- (CH ₂ CH ₂ 0) _s -R ⁴ (III)

in which R ^{3 is} a linear or branched alkyl radical or alkenyl radical having 5 to 18 carbon atoms or a cyclic alkyl radical having 5 to 6 carbon atoms, s is a number in the range from 2 to 12 and R ^{4 is} a linear or branched alkyl radical 1 to 8 carbon atoms, the weight ratio of components (a + b): c being in the range from 1: (0.1 to 4).

In the general formula (III) of the surfactant components c given above, R ³ therefore represents a linear or branched alkyl radical or alkenyl radical having 6 to 18 carbon atoms or a cyclic alkyl radical having 5 to 6 carbon atoms. Suitable substituents R ³ are therefore all those radicals which have already been explained above in connection with the substituent R ^{1 of} the general formula (I). The number of ethoxy radicals in the molecule - index s - here is in the range from 2 to 12. The substituent R ⁴ in the general formula (III) represents a linear or branched alkyl radical having 1 to 8 carbon atoms; thus for methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, n-heptyl _f n-octyl and for the corresponding branched chain isomers. Such alk (en) yl Mixed ethoxylate ethers, which are also referred to as end-group-closed fatty alcohol polyethylene glycol ethers, are described in more detail in German Offenlegungsschriften 33 15 951, 37 27 378 and 38 00 490. The production of these nonionic surfactants is also disclosed in detail in these German published publications.

For the purposes of the invention, it is preferred to use at least one alkyl ethoxylate mixed ether of the general formula (III) as additional component c of the surfactant combination, where R ^{3 is} a linear alkyl radical having 8 to 10 carbon atoms, s a Number in the range from 3 to 5 and R ^{4 is} an n-butyl radical. Particularly preferred mixed alkyl ethoxylate ethers of the general formula (III) are addition products of 3.5 to 4.5 mol of ethylene oxide onto fatty alcohols having 8 to 10 carbon atoms and etherified with an n-butyl radical.

The surfactant combinations to be used according to the invention are further characterized by a certain weight ratio of components a: b, which is generally in the range from 10: 1 to 1:10. If only these two components are used in the manner according to the invention, the preferred weight ratio of components a: b is in the range from 2: 1 to 1: 2. On the other hand, if the surfactant combination to be used according to the invention contains the additional component c, the weight ratio of components (a + b): c is in the range from 1: 0.1 to 1: 4, preferably in the range from 1: 0.1 to 1: 1.5.

The surfactant combinations to be used according to the invention are notable for high cleaning power at temperatures in the range from 15 to 80 ° C. They are in the temperature range mentioned Moreover, it can also be used without problems in the spraying process, since they do not cause any undesirable foam development. Further advantages are: very good wetting properties, very good demulsifying properties with regard to non-self-emulsifying oils and fats as well as easy assembly with additives commonly used in industrial cleaners.

Possible additives which are preferably used in the context of the invention in addition to the surfactant combinations to be used according to the invention are: framework substances and / or complexing agents, corrosion inhibitors and bases or acids. If necessary, stabilizers, solubilizers or antimicrobial agents can also be used as additives.

As builders and / or complexing agents, for example, alkali metal orthophosphates, polyphosphates, silicates, borates, carbonates, polyacrylates and gluconates can be used, as well as phosphonic acids or phosphonoalkane carboxylic acids or their water-soluble alkali metal salts, for example l-hydroxyethane-l, l -diphosphonic acid or 2-phosphonobutane-l, 2,4-tricarboxylic acid. Straight-chain or branched aliphatic carboxylic acids or their salts are suitable as effective corrosion inhibitors. In particular, alkanolamine salts of straight-chain or branched monocarboxylic acids with 8 to 11 carbon atoms are used as corrosion inhibitors. Depending on the intended use, the aqueous solutions of the surfactant combinations to be used according to the invention can be acidic or also alkaline; accordingly, they contain excess acid or bases, for example sodium hydroxide and / or potassium hydroxide.

The surfactant combinations to be used according to the invention are prepared by simply mixing the individual components In the same way, corresponding powdery or liquid cleaning agents are also produced by mixing the surfactant combinations to be used according to the invention with the other additives and, if appropriate, water. For the purposes of the invention, cleaning agents of this type contain 1 to 70% by weight, preferably 2 to 20% by weight, of the surfactant combinations to be used according to the invention.

For the purposes of the invention, the surfactant combinations to be used according to the invention are preferably used in the form of application solutions diluted with water. Such application solutions preferably contain the surfactant combinations to be used according to the invention in concentrations of 0.0001 to 1.5% by weight, in particular 0.0005 to 0.5% by weight. Ready-to-use application solutions of this type which are used in the sense of the invention for cleaning hard surfaces in the spraying process can likewise be strongly acidic to strongly alkaline (pH values in the range from

I to 14) and preferably have pH values in the range from 3.5 to

II on. Such application solutions are prepared by simply mixing the surfactant combinations with water.

The invention is illustrated by the examples below.

example 1

Surfactant combinations according to the invention

The abbreviations used below have the following meaning: EO = ethylene oxide, PO = propylene oxide

A 10 parts hexanol + 10 EO

1 part Cι ₂ _i8 fatty alcohol + 2 EO + 4 PO

B 1 part octanol + 4 EO

1 part Cι ₂ _i8 fatty alcohol + 3 EO + 6 PO

C 10 parts octadecenol + 2 EO

1 part Cι ₂ _i8 fatty alcohol + 3 EO + 6 PO D 1 part decanol + 2.9 EO

10 parts Cι ₂ _i8 fatty alcohol + 4 EO + 5 PO

E 1 part octanol + 4 EO

2 parts Cι _i4 fatty alcohol + 5 EO + 4 PO F 1 part octanol + 4 EO

5 parts Cι _i8 fatty alcohol + 3 EO + 6 PO

1 part of Cs-io fatty alcohol + 4 EO-butyl ether

G 1 part hexanol + 2.5 EO

1 part Cι ₂ _i4 fatty alcohol + 5 EO + 4 PO

3 parts Cs-io fatty alcohol + 3 EO-butyl ether H 1 part octanol + 4 EO

1 part Cι _i8 fatty alcohol + 4 EO + 5 PO Example 2

Detergent basics, as additives to the surfactant combinations according to the invention

Basis 1:

55.3 parts water

7.0 parts of ethanolamine

10.0 parts triethanolamine

8.0 parts diethanolamine

15.0 parts of Cg carboxylic acid, branched

1.0 part of 2-phosphonobutane-l, 2,4-tricarboxylic acid

0.2 parts tolyltriazole

3.5 parts of pentapotassium triphosphate

Basis 2:

59.2 parts water

10.0 parts ethanolamine

10.0 parts triethanolamine

5.0 parts diisopropanolamine

5.0 parts of n-octanoic acid

2.0 parts of Cg carboxylic acid, branched,

5.0 parts of Cs carboxylic acid, branched

3.0 parts boric acid

0.8 parts polyacrylate (MW approx. 1500)

Basis 3:

1 part disodium tetraborate x 10 H ₂ 0 1 part tetrasodium diphosphate x 10 H ₂ 0 Basis 4:

72.3 parts water

9.0 parts of potassium hydroxide

2.5 parts sodium hydroxide

5.0 parts of pentapotassium triphosphate

5.0 parts of potassium gluconate

5.0 parts mixture of branched carboxylic acids with 9 to 11 carbon atoms

(Versatic acid, Shell)

1.2 parts of l-hydroxyethane-l, l-diphosphonic acid

Basis 5:

80.0 parts water 15.0 parts o-phosphoric acid 5.0 parts sodium hydroxide

Basis 6:

1 part of pentasodium triphosphate

1 part tetrasodium diphosphate

1 part trisodium phosphate x 12 H ₂ 0

Example 3

The performance properties of the surfactant combinations according to Example 1 to be used according to the invention were tested in the detergent basics according to Example 2 in a laboratory spraying system. In this test, steel sheets (quality St 37), which were contaminated with corrosion protection oil, were treated with aqueous solutions, which are characterized in more detail in Table 1 below, treated by spraying (spray pressure 2.5 to 5 bar). The cleaning effect, the foaming behavior and the wetting of the sheet metal surfaces and the runoff behavior of the application solutions from the sheet metal surfaces were assessed visually.

In all cases of the individual examples summarized in Table 1, the tested application solutions showed a good cleaning effect. Furthermore, it was found that the application solutions used were readily sprayable at the temperatures given in Table 1 and showed no disruptive foam developments. The results obtained with regard to "wetting" and "run-off behavior" are each shown in Table 1 in the "Comments" column.

The individual columns in Table 1 are explained below:

"Basis":

Indication of the number of the detergent base used in the respective example according to Example 2.

"Surfactant combination":

Indication of the designation (No.) of the surfactant combination used in the respective example according to Example 1;

"Percentage": means the respective concentration of the surfactant combination based on the detergent base in% by weight.

"Concentration":

Concentration of the detergent in the application solution in g / i. "Water quality":

Quality of the water used to prepare the application solutions in terms of water hardness; it means: VEW = demineralized water DIN = water hardness 20 ° d BW = process water, hardness approx. 15 ° d.

"Spray temperature":

Temperature of the application solution when used in the spraying process, without disruptive foaming.

In the case of Example 3.8, aluminum sheets were additionally treated. No undesirable discoloration of the aluminum surface was observed.

T a b e l l e 1 Application studies

Surfactant combination Concentrate water spray Remarks No. Art. Tration quality temp. (% By weight) (g / 1) from (° C)

B 15 VEW 40 even wetting + even drain D 10 VEW 50 as in Example 3.1

3.3 10 DIN 30 fast expiry without

Drop formation

3.4 E 15 VEW 55 very even

Wetting

3.5 A 20 VEW 50 as in Example 3.4

3.6 A 10 VEW 20 as in Example 3.4

3.7 B BW 35 as in Example 3.4

3.8 E 20 BW 45 as in Example 3.

continuation

Continuation of table 1

Example: basic surfactant combination conc. Water, spraying, comments no. Length no. Proportion tration quality temp. No. (% by weight) (g / 1) a (° C)

3.9 20 BW 20 rapid flow of the solution without droplet formation very uniform wetting uniform wetting + even flow as in Example 3.11 fast process without droplet formation

3.14 15 BW 30 very even wetting

3.15 H 100 10 BW 45 as in Example 3.14 3.16 F 100 5 DIN 35 as in Example 3.13

Claims

Patent claims

1. Use of a combination of nonionic surfactants, containing:

(a) at least one alk (en) yl ethoxylate of the general formula (I)

R ¹ -0- (CH ₂ CH ₂ 0) _n -H (I)

in which R1 is a linear or branched alkyl radical or alkenyl radical having 5 to 18 carbon atoms or a cyclic alkyl radical having 5 to 6 carbon atoms and n is a number in the range from 2 to 12, and

(b) at least one alk (en) yl ethoxylate propoxylate of the general formula (II)

R ² -0- (CH ₂ CH ₂ 0) _p -AH (II)

in which R is a linear or branched alkyl radical or alkenyl radical having 6 to 18 carbon atoms or a cyclic alkyl radical having 5 to 6 carbon atoms, p is a number in the range from 2 to 10 and A radicals of the type - (CH -CH (CH ₃ ) -0) _q - and - (CH (CH ₃ ) -CH ₂ -0) _r - mean, the sum (q + r) being a number in the range from 2 to 8 , the weight ratio of components a: b in the range of

10: 1 to 1:10, for cleaning hard surfaces.

2. Use according to claim 1, characterized in that as component a of the surfactant combination at least one alk (en) yl ethoxylate of the general formula (I) in which R * is a linear AI kylrest or alkenylrest with 6 to 18 carbon atoms and n is a number i

^• i range from 2 to 10, is used.

3. Use according to claim 1, characterized in that as component b of the surfactant combination at least one alkyl ethoxylate propoxylate of the general formula (II), in which R ^{2 is} a linear alkyl radical having 8 to 18 carbon atoms, p is a number in the range from 2 to 5 and A is the abovementioned radicals, the sum (q + r) being a number in the range from 4 to 6, is used.

4. Use according to one of claims 1 to 3, characterized gekenn¬ characterized in that the surfactant combination as additional component c at least one alk (en) yl ethoxylate mixed ether of the general formula (III)

R -0- (CH CH ₂ 0) _s -R ⁴ (III)

in which R ^{3 is} a linear or branched alkyl radical or alkenyl radical having 6 to 18 carbon atoms or a cyclic alkyl radical having 5 to 5 carbon atoms, s is a number in the range from 2 to 12 and R ^{4 is} a linear or branched alkyl radical 1 to 8 carbon atoms, contains, the weight ratio of components (a + b): c in the range of 1: (0.1 to 4).

5. Use according to claim 4, characterized in that as i additional component c of the surfactant combination at least one alkyl ethoxylate mixed ether of the general formula (III) in which R ³

* a linear alkyl radical having 8 to 10 carbon atoms, s is a number in the range from 3 to 5 and R ^{4 is} an n-butyl radical.

6. Use according to any one of claims 1 to 5, characterized gekenn¬ characterized in that the surfactant combination additionally contains builders and / or complexing agents, corrosion inhibitors and bases or acids.

7. Use according to one of claims 1 to 6, characterized gekenn¬ characterized in that the surfactant combination in diluted with water application solutions in concentrations from 0.0001 to 1.5 wt .-%, preferably from 0.0005 up to 0.5 wt .-%, is used.