EP0986631A1

EP0986631A1 - Low-foam detergent

Info

Publication number: EP0986631A1
Application number: EP98937430A
Authority: EP
Inventors: Jürgen Geke; Bernd Stedry; Nicole Völler
Original assignee: Henkel AG and Co KGaA
Current assignee: Henkel AG and Co KGaA
Priority date: 1997-06-06
Filing date: 1998-05-29
Publication date: 2000-03-22
Anticipated expiration: 2018-05-29
Also published as: CA2293524A1; JP2002508794A; AR012941A1; ES2169536T3; HUP0003711A2; WO1998055578A1; ATE210718T1; TR199902907T2; KR20010013301A; EP0986631B1; DE19723990A1; CZ289755B6; DE59802449D1; US6187737B1; PL337232A1; AU8623998A; CN1259164A; ZA984853B; BR9810413A; CZ9904371A3

Abstract

The invention relates to a detergent concentrate containing glycol ether and cationic surfactants. It is characterized in that it contains less than 0.1 wt. % fatty alcohol polyglycol ether and/or amphoteric surfactants, and that it contains a) glycol ether of general formula R-O-(CH2-CH(CH3)-O)n-H, in which R is an alkyl radical with 1-4 C-atoms or a phenyl radical, and n is a number between 1 and 5, and b) cationic surfactants. The weight ratio of a) to b) is between 8:1 and 100:1.

Description

"Low-foaming cleaning agent"

The invention relates to a cleaning agent for hard, in particular metallic, surfaces. It therefore represents a so-called industrial cleaner, in particular a so-called neutral cleaner. Because of its special combination of glycol ether and cationic surfactants, it is low-foaming and can therefore be used preferably as a spray cleaner in the entire temperature range from about 15 to about 80 ° C. relevant to the application.

Industrial cleaners of this type are mainly used in the automotive industry and their supplier industries for cleaning and passivation, primarily 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, silumin, 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 light 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 Such cleaning agents usually contain substances that are able to counteract undesirable 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 - under the given working conditions. H. especially in spraying processes - give rise to undesirable foaming, for example anionic surfactants or nonionic surfactants foaming at the respective working temperature.

From "Ullman's Encyclopedia of Industrial Chemistry", 4th edition, volume 22 (1982), pages 489 to 493, the use of fatty alcohol polyethylene glycol ethers - also called fatty alcohol ethoxylates - as surfactant components in washing and cleaning agents is known. However, Addition products of this type of ethylene oxide to fatty alcohols of this type are not suitable only for use in spray processes, since they foam strongly at application temperatures in the range from 15 to 80 ° C. It is also known to use fatty alcohol ethoxylate propoxylates as low-foaming detergent raw materials, cf., for example, those cited above Ulimann volume, page 494.

DE-A-36 20 01 1 describes cationic surfactants based on quaternary ammonium compounds and their use in cleaning agents. The cationic surfactants are used in the alkaline pH range in addition to other detergent components. EP-A-0 116 151 describes a process for the regeneration or recycling of aqueous degreasing and cleaning solutions by adding cationic surfactants or cationic modified polymers or mixtures thereof.

EP-A-0 054 895 describes a surfactant mixture of a nonionic surfactant and a quaternary ammonium compound as a cationic surfactant for cleaning hard surfaces. The mixture contains the nonionic surfactant in a proportion of 20 to 95% by weight, the cationic surfactant in a proportion of 5 to 80% by weight.

DE-A-40 14 859 describes a low-foam surfactant combination for cleaning hard surfaces, which consists of at least one quaternary ammonium compound and at least one alkyl polyethylene glycol mixed ether. These mixed ethers have either an acyclic alkyl or alkenyl radical with 6 to 18 carbon atoms or a cyclic alkyl radical with 5 to 6 carbon atoms. In addition, this surfactant combination can contain alkyl ethoxylates or alkyl ethoxylate propoxylates, each of which has an alkyl or alkenyl radical having 6 to 18 carbon atoms.

From EP-A-275 987 a cleaning agent for compressors of gas turbines is known which contains 4 to 95% by weight glycol ether, 0.1 to 14% by weight nonionic surfactant, 0.01 to 6% by weight cationic surfactant and 0 contains up to 95 wt .-% water. EP-A-691 397 discloses an antimicrobial cleaner for hard surfaces which contains C 6 -alkanol-C3-24-alkylene glycol ether, amphoteric and / or nonionic surfactants, cationic surfactants, builders and water as solvents. DE-C-41 02 709 proposes a means for degreasing metal surfaces which contains 15 to 30% by weight of adducts of lower alkylene oxides with fatty alcohols with cloud points below 50 ° C, 0.5 to 3% by weight of cationic surfactants and 10 to Contains 20 wt .-% auxiliary solvent from the group of C2-5 ~ alkanols and lower glycol ether in water. Accordingly, agents are known which contain fatty alcohol ethoxylates, cationic surfactants and lower glycols as solvents or solubilizers. The invention is based on the surprising finding that, with a suitable combination of glycols and cationic surfactants, an excellent cleaning action is achieved without these agents additionally containing amphoteric surfactants or fatty alcohol alkoxylates having a surfactant action, such as ethoxylates or propoxylates. Here, fatty alcohol alkoxylates are understood according to the disclosure of EP-A-691 397 alkoxylates of alcohols with at least 6 carbon atoms in the alkyl radical.

All sprayable surfactant systems have a number of disadvantages in the application concentration of about 0.5 to about 5% by weight:

1. To ensure low foam, the application is above the so-called cloud point. The application solutions are therefore clouded by a dispersed, surfactant-rich phase. This phase, which is rich in surfactants, is easily separated by conventional measures to extend the service life, such as skimmers, separators, centrifuges or membrane filtration, and is no longer available for the cleaning process.

2. The usual nonionic surfactant systems such as fatty alcohol or fatty amine ethoxylates or propoxylates and their mixed ethers are classified in water hazard class 2.

3. The highly degreasing nonionic surfactants, for example fatty alcohol ethoxylates with more than 4 moles of ethylene oxide or fatty amine ethoxylates with more than 5 moles of ethylene oxide, which themselves have no cloud point at the usual application temperatures, foam extremely strongly and are not suitable for spray applications alone. Rather, anti-foaming agents must be added that make little or no contribution to the cleaning performance itself. In order to incorporate these anti-foaming agents into the liquid cleaner concentrates, solubilizers, so-called hydrotropic substances required to obtain clear concentrates. These solubilizers represent another ballast that does not itself contribute to the cleaning performance.

In contrast, the object of the invention is to provide a new cleaning-effective combination of substances which does not have the disadvantages mentioned above. In particular, a new cleaning-active substance combination is to be provided, which delivers clear, low-foaming and sprayable cleaning solutions in the practical temperature range from about 15 to about 80 ° C, without the need for additional defoamers and solubilizers.

This object is achieved by a cleaning agent concentrate containing glycol ether and cationic surfactants, characterized in that it contains less than 0.1% by weight of fatty alcohol alkoxylates and / or amphoteric surfactants and that it contains a) glycol ethers of the general formula RO- (CH ₂ -CH ( CH ₃ ) -O) _n -H, where R is an alkyl radical with 1 to 4 carbon atoms or a phenyl radical and n is a number in the range from 1 to 5, and b) cationic surfactants in the weight ratio a) to b) between 8: 1 and 100: 1 contains.

Glycol ethers of the abovementioned formula are preferably used in which R is an alkyl radical having 1 to 4 carbon atoms or a phenyl radical and n is a number in the range from 1 to 3. It is further preferred that the detergent concentrate contains glycol ethers and cationic surfactants in the weight ratio a): b) between 8: 1 and 25: 1.

This cleaning agent concentrate preferably contains the glycol ethers a) in the concentration range from about 5 to about 200 g / 1 and the cationic surfactants b) in the concentration range from about 0.2 to about 25 g / 1. The rest is water or an aqueous solution of other active ingredients or auxiliaries, in particular corrosion inhibitors.

Glycol ethers which can be used according to the invention are, for example, tripropylene glycol monoethyl ether, dipropylene glycol n-butyl ether,

Tripropylene glycol n-butyl ether and propylene glycol phenyl ether. Tripropylene glycol monomethyl ether and tripropylene glycol n-butyl ether are preferably used.

The cationic surfactants b) are preferably selected from quaternary ammonium compounds of the general formula Rl- (CHOH-CHR ² ) _n -N ⁺ R3R4R5 χ ~ in the

Rl is a linear or branched alkyl radical having 1 to 22 carbon atoms,

R2 may be hydrogen or a linear or verweigter alkyl radical having 1 to 22 carbon atoms, the total number of C atoms of the radicals R and R ² in the range of

10 to 22, n = 0 or 1,

R ^ and R ^ independently of one another for methyl, ethyl, 2-hydroxyethyl or

Hydroxypropyl,

R5 represents alkyl radicals with 1 to 12 atoms, a benzyl radical or alkylphenyl radicals with 1 to 3 C atoms in the alkyl radical and the total number of carbon atoms of the quaternary ammonium cation is at least 9 and at least one of the radicals Rl and R ^ is more than 4

Has carbon atoms, and

X "stands for halide, methyl sulfate or an anion of an aliphatic or aromatic organic acid with up to 15 carbon atoms.

Cationic surfactants are preferably used in which, in the general formula given, R3 and R4 are methyl and R ^ is benzyl. Examples of such cationic surfactants are lauryl-dimethyl-benzylammonium salts or 2-hydroxydodecyl-dimethyl-benzylammonium salts. Anions X "in these salts are, for example, halides, in particular chloride, or anions of organic acids which form water-soluble salts with the quaternary ammonium ions. Examples of such organic anions are acetate, propionate, lactate or benzoate.

The use of such cationic surfactants together with nonionic surfactants for low-foam industrial cleaners is known, for example, from DE-A-40 14 859. There, however, these cationic surfactants are combined with nonionic surfactants with alkyl or alkenyl radicals with at least 5, preferably with 6 to 18, carbon atoms. In contrast, it is new and surprising that the glycol ethers a) can be used instead of these customary nonionic surfactants. Since these have an alkyl radical with only 1 to 4 carbon atoms, it is surprising that they have a degreasing effect at all. Compared to the nonionic surfactants of the prior art, they have the ecological advantage of being classified in water hazard class 1. Together with the cationic surfactants, they form clear application solutions in the use concentration of the detergent concentrate in water from about 0.5 to about 5% by weight, which are low-foaming in spray processes and whose cleaning performance is at least comparable to that of conventional spray cleaners.

The cleaning agent concentrates according to the invention can in principle be used in dilute aqueous application solution for cleaning purposes without further additives. However, since they are to be used primarily for cleaning unpainted metal surfaces, it is preferable that the cleaning agent concentrates additionally contain corrosion inhibitors. Their concentration in the concentrates is preferably in the range from about 100 to about 700 g / l. These corrosion inhibitors prevent the corrosion of the cleaned bare metal parts, if they are not processed directly, but instead are packed or stored in a damp place.

Alkanolamines, for example, can be used as corrosion inhibitors. Monoethanolamine, monoisopropanolamine, triethanolamine, triisopropanolamine or mixtures thereof are preferably used. Dialkanolamines could also be used due to their excellent corrosion protection. For toxicological reasons (danger of nitrosamine formation), however, the use of dialkanolamines is avoided today.

Furthermore, the corrosion inhibitors can be selected from branched or unbranched, saturated or unsaturated aliphatic carboxylic acids with 6 to 10 C atoms and / or from aromatic carboxylic acids with 7 to 10 C atoms. At the desired pH values of the so-called neutral cleaners, which are in the range from about 6.5 to about 9, the carboxylic acids are largely present as anions. Counterions with which the acids can be neutralized are, for example, alkali metal ions such as, in particular, sodium or potassium ions, but preferably the cations of the alkanolamines listed above.

Examples of suitable carboxylic acids are caproic acid, caprylic acid, ethylhexanoic acid, heptanoic acid, isononanoic acid and benzoic acid or their derivatives, in particular 3-nitrobenzoic acid or 4-hydroxybenzoic acid.

The cleaning agent concentrates may contain further auxiliaries or active substances: builder substances such as, for example, alkali metal orthophosphates, polyphosphates, silicates, borates, carbonates, polyacrylates and gluconates. Some of these builder substances also have complexing properties and therefore have a water-softening effect. Instead of or in addition to this, stronger ones Complexing agents such as l-hydroxyethane-l, l-diphosphonic acid or 2-phosphonobutane-l, 2,4-tricarboxylic acid can be used. Ethylene diamine tetraacetate and nitrilotriacetate can also be used, but may cause problems in wastewater treatment. To protect the cleaning agent concentrates and the application solutions made from them against germs, biocides can be added if desired.

The cleaning agent characterized above represents a concentrate from which the ready-to-use cleaning solution can be prepared by dilution. In principle, it would be possible to prepare the cleaning solution by dissolving the individual active components in water in the required concentration range. In the industrial sector concerned, however, it is common for the manufacturer to supply concentrates which contain all the active ingredients in the required proportions and from which the user can prepare the ready-to-use cleaning solution by simply diluting with water. The concentrates are usually adjusted so that they are used as about 0.5 to about 5% by weight aqueous solution, ie they are diluted for use with water in a ratio of about 1: 200 to about 1:20 . Accordingly, the invention also comprises a ready-to-use aqueous cleaning agent which can be obtained by diluting the cleaning concentrate according to one or more of claims 1 to 7, as described in more detail above, in a ratio of 1: 200 to 1:20 with water. This aqueous cleaning agent is used in particular for degreasing metal parts in spraying systems, a temperature in the range from about 15 to about 80 ° C. and in particular in the range from about 15 to about 30 ° C. being set for this. Embodiments

example 1

Aqueous application solutions according to the invention and comparison solutions according to the prior art were compared with one another with regard to the cleaning result, surfactant separation and foaming behavior. For this, were initially through

Mixing the individual components made of detergent concentrates.

For the application tests, these were diluted with water as indicated below.

Test results:

A basic cleaner formulation, which consists of 30% triethanolamine and 4% isononanoic acid and the remainder 100% water, is mixed with various "surfactants" and then subjected to a cleaning, surfactant separation and foam test (all percentages are percentages by weight).

Surfactants: a) 5.0% tripropylene glycol monomethyl ether

0.5% 2-hydroxydodecyl-dimethyl-benzyl-ammonium-benzoate b) 5.0% coconut amine + 12 EO c) 5.0% fatty alcohol C \ 2 / \ 4 + 3 EO + 6 PO d) 5.0% octanol + 4.5 EO-butyl ether with a narrow homolog distribution, each 100% filled with condensed water. Abcd surfactant mixture

(invention (comparison) (comparison) (comparison) according to)

Cleaning result ++ ++ __. __

Surfactant separation ++ ++ _. ..

Foam behavior + + ++

++ = very good cleaning, no surfactant separation, no foam + = good cleaning, foam height in the spraying process <= 1.5 cm ~ = practically no cleaning, strong surfactant separation, strong foaming

Example 2

Further aqueous application solutions according to the invention with different glycol ethers e), f) and g) were tested:

Cleaner formulation: 1.2% by weight citric acid 1.5% by weight isononanoic acid 10.4% by weight boric acid 3.8% by weight triethanolamine 1 1.2% by weight monoethanolamine 2.0% by weight glycol ether e), or g) 0.15% by weight of 2-hydroxydodecyldimethylbenzylammonium benzoate (50%

Solution) rest of water Glycol ether e) Dipropylene glycol n-butyl ether f) Tripropylene glycol n-butyl ether g) Propylene glycol phenyl ether

Test results:

Glycol ether e g

Cleaning result ++ +

Surfactant separation ++

Foam behavior + + +

Description of the test methods:

1. Cleaning test

Steel sheets of quality St 1405 are pre-cleaned manually with surfactant solution and soiled with lapping paste (original dirt from practice). After 2 days of storage in an oven at 60 ° C, they are sprayed with a 2% detergent solution in a laboratory spraying system at 60 ° C for 10 minutes. The surfaces are assessed visually and the residual contamination is determined gravimetrically.

Very good cleaning means that> 99% of the dirt has been removed, practically no cleaning means a result <70%.

2. Surfactant separation

A 2% cleaning solution is placed in a 1000 ml beaker (tall form)

Set water at 20 ° dH, 5 min on a magnetic stirrer at approx. 600 Stirred revolutions per minute and then stored for 24 hours at 60 ° C in the oven without moving the bath. The appearance of the solution and the deposition on the liquid surface are assessed.

Evaluation criteria:

++ = no visible deposits o = deposits visible, solution clearly cloudy

~ = strong deposits, clear solution

3. Behave foam

2% by weight cleaning solutions in water with a degree of hardness corresponding to 20 ° dH were prepared from the concentrates according to recipes a to d. In each case 10 1 of this solution were sprayed with temperatures in the range between approximately 30 and approximately 45 ° C. in a single-nozzle spraying system with a spray pressure of 5 bar for a period of 60 minutes. During the operation of the spray system, the foam height was measured, which is defined as the height of the foam above the liquid level in the initial state.

The evaluation is as follows:

++ = no foam

+ = Foam height <1.5 cm o = foam height <4.0 cm

- = foam height <5.5 cm

- = system switches off because foam height> 5.5 cm

As can be seen from the test results, the agents according to the invention offer clear advantages over existing systems.

Claims

claims

1. detergent concentrate containing glycol ether and cationic surfactants, characterized in that it contains less than 0.1 wt .-% fatty alcohol alkoxylates and / or amphoteric surfactants and that it

a) glycol ethers of the general formula RO- (CH ₂ -CH (CH) -0) _n -H, where R is an alkyl radical with 1 to 4 carbon atoms or a phenyl radical and n is a number in the range from 1 to 5, and

b) cationic surfactants

contains in the weight ratio a) to b) between 8: 1 and 100: 1.

2. Detergent concentrate according to claim 1, characterized in that it contains glycol ethers of the general formula R-0- (CH -CH (CH ₃ ) -0) _n -H, where R is an alkyl radical having 1 to 4 carbon atoms or a phenyl radical and n is a number in the range of 1 to 3.

3. Detergent concentrate according to one or both of claims 1 and 2, characterized in that it contains glycol ether a) and cationic surfactants b) in the weight ratio a) to b) between 8: 1 and 25: 1.

4. Detergent concentrate according to one or more of claims 1 to 3, characterized in that it contains 5 to 200 g / 1 glycol ether a) and 0.2 to 25 g / 1 cationic surfactants b) and the remainder water or an aqueous solution of further active ingredients. or contains auxiliary substances.

5. Detergent concentrate according to one or more of claims 1 and 4, characterized in that the cationic surfactants b) are selected from quaternary ammonium compounds of the general formula

Rl- (CHOH-CHR2) _n -N + R3R4R5 χ ~

in the

Rl is a linear or branched alkyl radical having 1 to 22 carbon atoms,

R2 is hydrogen or a linear or branched alkyl radical with 1 to 22 C-

Can be atoms, the total number of carbon atoms of the radicals R and R ² im

Range from 10 to 22, n = 0 or 1,

R3 and R ^ independently of one another for methyl, ethyl, 2-hydroxyethyl or

Hydroxypropyl,

R5 for alkyl radicals with 1 to 12 atoms, a benzyl radical or for

Alkylphenyl radicals with 1 to 3 carbon atoms in the alkyl radical and the total number of carbon atoms of the quaternary ammonium cation is at least 9 and at least one of the radicals R ^ and R ^ more than 4

Has carbon atoms, and

6. detergent concentrate according to claim 5, characterized in that in the general formula of the cationic surfactants R ^ and R ^ are methyl and R ^ is benzyl.

7. detergent concentrate according to one or more of claims 1 to 6, characterized in that it contains 100 to 700 g / 1 corrosion inhibitors as further active ingredients.

8. Detergent concentrate according to claim 7, characterized in that the corrosion inhibitors are selected from acanolamines and / or from branched or unbranched, saturated or unsaturated aliphatic carboxylic acids with 6 to 10 carbon atoms and / or from aromatic carboxylic acids with 7 to 10 carbon atoms .

9. detergent concentrate according to one or more of claims 1 to 8, characterized in that it additionally contains builder substances, biocides and / or complexing agents.

lO.Aqueous cleaning agent, which can be obtained by

Detergent concentrate according to one or more of claims 1 to 9 in a ratio of 1: 200 to 1: 20 diluted with water.

1 1. Use of the aqueous cleaning agent according to claim 10 for degreasing metal parts in spraying systems.

PCT / EP 98/03223

A CLASSIFICATION OF SUBJECT MATTER

IPC ⁶ C 11 D 3/43, C 11 D 1/835, C 11 D 1/62

According to International Patent Classification (IPC) or to both national classification and IPC

B FIELDS SEARCHED

Minimum documentation searched (classification system followed by classification symbols)

IPC ⁶ C 11 D

Documentation searched other than minimum documentation to the extent that such documents are included in the fields searched

Electronic data base consulted duπng the international search (name of data base and, where practicable, search terms used)

C DOCUMENTS CONSIDERED TO BE RELEVANT

Category * Citation of document, with indication, where appropnate, of the relevant passages Relevant to claim No

EP 0261874 A2 1, 2, 4,

(THE PROCTER & GAMBLE COMPANY) 6-9, 1 1

30 Marc 1988 (30.03.88), page 2, line 40 - page 3 _; l ine 39, Claims 1 -3, 7, 8.

EP 0288856 A2 1 -10

(HENKEL KGAA) November 2, 1988 (02.1 1 .88), Cl aims.

DE 4014859 A1 1 -1 1

(HENKEL KGAA) November 14, 1991 (November 14, 1991), Claims (c ited in the description).

EP 0054895 A1 1 -11

(HOECHST AG) 30 June 1982 (30.06.82), Claims (cited in the description).

EP 0691397 A2 -10

(THE CL0R0X COMPANY) 10 January 1996 (10.01.96), the hole document (c ited in the description).

X I Further documents are hsted in the design of Box C | | See patent family annex

* Special categories of cited documents "T" later document published after the international filing date or pπoπty

"A" document defining the general State of the art hich is not considered date and not in conflict with the apphcation but cited to understand to be of particular relevance the pπnciple or theory underlying the mveπtion

"E" earher document but published on or after the international filing date "X" document of particular relevance, the claimed invention cannot be considered novel or cannot be considered to involve an inventive

"L" document which may throw doubts on pπoπty claun (s) or which is step when the document is taken alone cited to estabhsh the pubhcaüon date of another citation or other Special reason (as specified) "Y" document of particular relevance, the claimed invention cannot be

"O" document refemng to an oral disclosure, use, exhibitor or other considered to involve an inventive step when the document is means combined with one or ore other such documents, such combination being obvious to a person skilled in the art

"P" document published pπor to the international filing date but later than the pnonty date claimed "&" document member of the same patent family

Date of the actual completion of the international search Date of mailing of the international search report

October 6, 1998 (October 6, 1998) November 9, 1998 (November 9, 1998)

Name and mailing address of the ISA / Authoπzed officer

European Patent Off ice

Facsraule No Telephone No

Form PCT / ISA 210 (second sheet) (July 1992)