EP1910482A1

EP1910482A1 - Method for coating surfaces

Info

Publication number: EP1910482A1
Application number: EP06777683A
Authority: EP
Inventors: Andreas FECHTENKÖTTER; Bernd DÜTTRA; Michael Ehle; Martin Scholtissek
Original assignee: BASF SE
Current assignee: BASF SE
Priority date: 2005-07-19
Filing date: 2006-07-11
Publication date: 2008-04-16
Also published as: DE102005034215A1; US20080200604A1; WO2007009909A1

Abstract

The invention relates to a method for coating surfaces using: (A) at least one ethylene copolymer wax, selected from ethylene copolymer waxes containing comonomers obtained by polymerisation and comprising (a) between 15 and 40 wt. % of at least one ethylenically unsaturated carboxylic acid and (b) between 60 and 85 wt. % of ethylene, and ethylene copolymer waxes containing the following obtained by polymerisation (a') between 14.5 and 39.9 wt. % of at least one ethylenically unsaturated carboxylic acid, (b') between 60 and 79.4 wt. % ethylene and (c') between 0.1 and 15 wt. % esters of an ethylenically unsaturated carboxylic acid, each in at least partially neutralised form; and (B) at least one additional wax that is not an ethylene copolymer wax (A).

Description

Process for coating surfaces

The present invention relates to a method of coating surfaces using

A) at least one ethylene copolymer wax, selected from those ethylene copolymer waxes which contain copolymerized as comonomers

(a) from 15 to 40% by weight of at least one ethylenically unsaturated carboxylic acid and (b) from 60 to 85% by weight of ethylene, and such ethylene copolymer waxes containing in copolymerized form (a ¹ ) from 14.5 to 39.9% by weight at least one ethylenically unsaturated carboxylic acid,

(b ¹ ) 60 to 79.4% by weight of ethylene and (c ¹ ) 0.1 to 15% by weight of ester of an ethylenically unsaturated carboxylic acid, in each case in at least partially neutralized form, and

B) at least one further wax other than ethylene copolymer wax (A).

In many cases one would like to coat surfaces that are exposed to a considerable extent environmental influences. Due to a hydrophobic coating otherwise hydrophilic surfaces become water repellent. Water swellable substrates are thus less vulnerable, and metallic substrates are less susceptible to corrosion.

For the purpose of coating various technical possibilities are known. So you can, for example, paint. Another method is to provide the surface in question with a hydrophobic film.

DE 34 20 168 discloses wax dispersions for floor care which contain:

1. 5 to 20 wt .-% of an aqueous secondary wax dispersion of 5 to 40

Wt .-%, based on the secondary wax dispersion, of an ethylene copolymer wax, consisting of 10 to 25 wt .-% of an α-olefinically unsaturated mono- or dicarboxylic acid having 3 to 8 carbon atoms and 90 to 75 wt .-% of ethylene with an MFI value, measured at 190 ⁰ C and 2.16 kp, of 1 to 600, or an MFI value, measured at 160 ⁰ C and 325 g, from 1 to 400, further comprises from 0.1 to 5 wt %, based on the secondary wax dispersion, alkali metal hydroxide, ammonia, alkanolamine, dialkylalkanolamine and their mixtures, and optionally

From 1 to 5% by weight of a nonionic or anionic emulsifier and the balance of water to 100% by weight, based on the secondary wax dispersion, and because of the total weight of wax dispersion for floor care,

2. 20 to 50 wt .-% of an aqueous primary dispersion having a solids content of 20 to 50 wt .-%, wherein (page 4, lines 21-24), the primary dispersion is a copolymer which is not a wax by itself,

3. 1 to 8% by weight of one or more plasticizers,

4. 0.2 to 2 wt .-% leveling agent and

5. 73.8 to 20 wt .-% water.

However, wax dispersions for floor care disclosed in DE 34 20 168 can still be improved for coatings.

Low cost hydrophobic materials are waxes such as paraffin waxes. In order to apply hydrophobic materials such as waxes in the form of a film to surfaces, it is necessary to dissolve either the organic wax (s) concerned, such as gasoline or toluene. However, coating using large amounts of organic solvent is undesirable. It was therefore attempted to apply paraffin wax in the form of an aqueous emulsion. This requires large amounts of emulsifiers (surfactants).

However, it can be observed that paraffin wax films are not very durable on many substrates such as stones, stoneware, terracotta, metal, wood, glass and cardboard and are easily removable mechanically. It is further observed that in many cases the effect of the coating decreases greatly over time. Finally, it is observed that paraffin wax films are often slightly cloudy and visually unfavorable.

It was therefore an object to provide a method for coating surfaces of substrates such as wood, glass and cardboard, which avoids the known from the prior art disadvantages. It was a further object to provide coated surfaces of articles with coated surfaces.

Accordingly, the method defined above was found.

According to the method of the invention, it is possible to coat surfaces which consist of any desired materials. It is preferable to coat surfaces of metals, lacquered or uncoated, cellulose-containing substrates, textile, natural and synthetic films and adhesives.

In one embodiment of the present invention, surfaces coated according to the present invention have a measurable hydrophilicity prior to coating. They usually belong to objects that you want to protect against attack by water or dissolved or dispersed in water substances. Surfaces to be coated in accordance with the invention can consist, for example, of stone, metal, or also of alloys of two or more metals, coated, galvanized or, preferably, unpainted. In other embodiments of the present invention, surfaces to be coated consist of cellulosic substrates, such as paper, cardboard, cardboard, wood, solid or chipboard, of adhesive, in particular hotmelts, preferably in the cured state, of paints, in particular overcoats, or of glass. Also suitable are surfaces made of synthetic materials such as polypropylene or polyethylene.

Objects with surfaces to be coated according to the invention can be, for example, cars in which, in particular, the subfloor can be coated in accordance with the invention, furthermore cartons. Wooden objects with surfaces to be coated according to the invention can be, for example, buildings or parts of buildings such as roof trusses or terraces, furthermore fences or benches. Also to be mentioned are stoneware and terracotta.

The method defined at the beginning is based on at least one ethylene copolymer wax (A) in at least partially neutralized form.

Ethylene copolymer waxes (A) used according to the invention are selected from those ethylene copolymer waxes which have been copolymerized as comonomers

(A) 15 to 40 wt .-%, preferably 19 to 35 wt .-%, particularly preferably 25 to 34 wt .-% of at least one ethylenically unsaturated carboxylic acid and

(b) 60 to 85% by weight, preferably 65 to 81% by weight, particularly preferably 66 to 75% by weight of ethylene, and those ethylene copolymer waxes (A) which contain in copolymerized form (a ¹ ) 14.5 to 39 , 9 wt .-%, preferably 19 to 28 wt .-% of at least one ethylenically unsaturated carboxylic acid,

(b ¹ ) 60 to 79.4 wt .-%, preferably 71, 5 to 81, 5 wt .-% of ethylene and (c ') 0.1 to 15 wt .-%, preferably 0.5 to 10 wt. % of at least one ester of an ethylenically unsaturated carboxylic acid.

By copolymerized comonomers are meant the proportions of comonomer which are incorporated molecularly into the ethylene copolymer waxes used according to the invention.

Preferably, the ethylenically unsaturated carboxylic acid (a) or (a ') used is at least one carboxylic acid of the general formula I, in which the variables are defined as follows: R ¹ and R ² are the same or different. R ¹ is selected from hydrogen and unbranched and branched C 1 -C 10 -alkyl, such as, for example, methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-butyl Pentyl, iso-pentyl, sec-pentyl, neo-pentyl, 1, 2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n Nonyl, n-decyl; particularly preferably C 1 -C 4 -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl, in particular methyl;

R ² is selected from straight-chain and branched Ci-Cio-alkyl such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl, tert-butyl, n-pentyl, iso -Pentyl, sec-pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl , n-decyl; particularly preferably C 1 -C ₄ -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl, in particular methyl; COOH, and most preferably hydrogen.

In one embodiment of the present invention, R ^{1 is} hydrogen or methyl. Most preferably, R ^{1 is} methyl.

In one embodiment of the present invention, R ^{1 is} hydrogen and R ^{2 is} COOH.

In one embodiment of the present invention, R ^{1 is} hydrogen or methyl and R ^{2 is} hydrogen.

Very particular preference is given to using ethylenically unsaturated carboxylic acid (a) or (a ¹ ) of the general formula I as methacrylic acid.

If it is desired to use several ethylenically unsaturated carboxylic acids to prepare ethylene copolymer wax (A) used according to the invention, two different ethylenically unsaturated carboxylic acids (a) or (a ') of the general formula I can be used, for example acrylic acid and methacrylic acid. In one embodiment of the present invention, for the preparation of ethylene copolymer wax (A) used according to the invention as the ethylenically unsaturated carboxylic acid (a) or (a '), (meth) acrylic acid and maleic acid are used.

In one embodiment of the present invention, only one ethylenically unsaturated carboxylic acid (a) is used to prepare ethylene copolymer wax (A) used according to the invention, in particular acrylic acid or methacrylic acid.

In one embodiment of the present invention, those ethylene copolymer waxes (A) are used which contain polymerized units

(a ¹ ) from 14.5 to 39.9% by weight, preferably from 19 to 28% by weight, of at least one ethylenically unsaturated carboxylic acid,

(b ¹ ) 60 to 79.4 wt .-%, preferably 71, 5 to 81, 5 wt .-% of ethylene and

(c ¹ ) 0.1 to 15 wt .-%, preferably 0.5 to 10 wt .-% of at least one ester of an ethylenically unsaturated carboxylic acid.

By ethylenically unsaturated carboxylic acids (a ') are meant the same ethylenically unsaturated carboxylic acids as described above.

Preferably, at least one ester of an ethylenically unsaturated carboxylic acid (c ') corresponds to a carboxylic acid ester of the general formula II,

where the variables are defined as follows:

R ³ and R ⁴ are the same or different.

R ³ is selected from hydrogen and unbranched and branched C ¹ -C 10 -alkyl, such as, for example, methyl, ethyl, n-

Propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, isopentyl, sec-pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl, n-decyl, particularly preferably C 1 -C ₄ -alkyl, such as methyl, ethyl, n-propyl, iso-propyl, n-butyl, iso-butyl, sec-butyl and tert-butyl, especially methyl.

R ⁴ is selected from straight-chain and branched C 1 -C 10 -alkyl, for example methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, iso -Pentyl, sec-pentyl, neo-pentyl, 1,2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl , n-decyl, more preferably C ^■ 1 - C 4 -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl

Butyl, especially methyl; and most preferably hydrogen.

R ⁵ is selected from straight-chain and branched C 1 -C 10 -alkyl, for example methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert-butyl, n-pentyl, iso -Pentyl, sec-pentyl, neo-pentyl, 1, 2-dimethylpropyl, iso-amyl, n-hexyl, iso -hexyl, sec-hexyl, n-heptyl, n-octyl, 2-ethylhexyl, n-nonyl , n-decyl, particularly preferably C 1 -C 4 -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl and tert-butyl, in particular methyl;

C ₃ -C 12 cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferred are cyclopentyl, cyclohexyl and cycloheptyl.

In one embodiment of the present invention, R ^{3 is} hydrogen or methyl. Most preferably, R ^{3 is} hydrogen.

In one embodiment of the present invention, R ³ and R ^{4 are} hydrogen.

Most preferably, R ^{5 is} methyl.

Very particular preference is given to using as the ester of an ethylenically unsaturated carboxylic acid of the general formula II methyl acrylate.

If it is desired to use a plurality of ethylenically unsaturated carboxylic acid esters (c ') for the preparation of ethylene copolymer wax (A) used according to the invention, it is possible to use, for example, two different ethylenically unsaturated carboxylic acid esters of the general formula II, for example methyl acrylate and methyl methacrylate.

In one embodiment of the present invention, methyl (meth) acrylate is used as the ethylenically unsaturated carboxylic acid ester of the general formula II to prepare ethylene copolymer wax (A) used according to the invention.

In one embodiment of the present invention, for the preparation of ethylene copolymer wax (A) used according to the invention, only one ethylenically unsaturated carboxylic acid ester and one ethylenically unsaturated carboxylic acid are used, in particular acrylic acid or methacrylic acid and (meth) acrylic acid methyl ester.

In one embodiment of the present invention, to prepare ethylene copolymer wax (A) used in the present invention, up to 0.5 parts by weight, based on the sum of the comonomers described above, further comonomers are copolymerized. Other comonomers may be selected, for example, from vinyl acetate and isobutene.

In another embodiment of the present invention, no further comonomers are copolymerized in to produce ethylene copolymer wax (A) used according to the invention.

In one embodiment of the present invention, ethylene copolymer wax (A) used according to the invention has a melt flow rate (MFR) in the range of 1 to 50 g / 10 min, preferably 5 to 20 g / 10 min, more preferably 7 to 15 g / 10 min , measured at 160 ⁰ C and a load of 325 g according to EN ISO 1133. Their acid number is usually 100 to 300 mg KOH / g wax, preferably 110 to 230 mg KOH / g wax, determined according to DIN 53402.

In one embodiment of the present invention, ethylene copolymer wax (A) used according to the invention has a kinematic melt viscosity v of at least 45,000 mm ² / s, preferably of at least 50,000 mm ² / s.

In one embodiment of the present invention, the melting range of the present invention ethylene copolymer wax (A) in the range of 50 to 110 ⁰ C, preferably in the range of 60 to 90 ⁰ C, determined by DSC in accordance with DIN 51,007th

In one embodiment of the present invention, the melting range may be wide, and a temperature interval of at least 7 to a maximum of 20 ⁰ C, preferably at least 10 ⁰ C and at most 15 ° C of the present invention relate to ethylene copolymer wax (A).

In another embodiment of the present invention, the melting point of ethylene copolymer wax (A) used according to the invention is sharp and is in a temperature range of less than 2 ° C, preferably less than 1 ° C, determined according to DIN 51007.

The density of ethylene copolymer wax (A) used according to the invention is usually 0.89 to 1.10 g / cm ³ , preferably 0.92 to 0.99 g / cm ³ , determined according to DIN 53479.

Ethylene copolymer waxes (A) used according to the invention may be alternating copolymers or block copolymers or preferably random copolymers.

Ethylene copolymer waxes (A) used according to the invention of ethylene and ethylenically unsaturated carboxylic acids and optionally ethylenically unsaturated carbohydrates. Biconic esters can advantageously be prepared by free-radically initiated copolymerization under high-pressure conditions, for example in stirred high-pressure autoclaves or in high-pressure tubular reactors. Production in stirred high pressure autoclave is preferred. High pressure autoclaves are known per se, a description can be found in Ullmann's Encyclopedia of Industrial Chemistry, 5th edition, keywords: Waxes, Vol. A 28, p. 146 ff., Verlag Chemie Weinheim, Basel, Cambridge, New York, Tokyo, 1996. With them predominantly the ratio length / diameter at intervals of 5: 1 to 30: 1, preferably 10: 1 to 20: 1 behaves. The equally applicable high-pressure tube reactors can also be found in Ullmann's Encyclopedia of Industrial Chemistry, 5th edition, keywords: Waxes, Vol. A 28, p 146 ff., Verlag Chemie Weinheim, Basel, Cambridge, New York, Tokyo, 1996.

Suitable pressure conditions for the polymerization are 500 to 4000 bar, preferably 1500 to 2500 bar. Conditions of this type are also referred to below as high pressure. The reaction temperatures are in the range from 170 to 300 ^° C., preferably in the range from 195 to 280 ^° C.

The polymerization can be carried out in the presence of a regulator. The regulator used is, for example, hydrogen or at least one aliphatic aldehyde or at least one aliphatic ketone of the general formula III

O

R ⁶ ^ ^ R ⁷

or mixtures thereof.

The radicals R ⁶ and R ^{7 are} identical or different and selected from

Hydrogen;

C ₁ -C ₆ -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, isobutyl, sec-butyl, tert.

Butyl, n-pentyl, iso-pentyl, sec-pentyl, neo-pentyl, 1, 2-dimethylpropyl, iso-amyl, n-hexyl, iso-hexyl, sec-hexyl, particularly preferably Ci-C ₄ alkyl such as methyl, ethyl, n-propyl, isopropyl, n -butyl, iso -butyl, sec -butyl and tert -butyl; C ₃ -C 12 cycloalkyl such as cyclopropyl, cyclobutyl, cyclopentyl, cyclohexyl, cycloheptyl, cyclooctyl, cyclononyl, cyclodecyl, cycloundecyl and cyclododecyl; preferred are cyclopentyl, cyclohexyl and cycloheptyl.

In a particular embodiment, R ⁶ and R ⁷ are covalently linked together to form a 4- to 13-membered ring. Thus, R ⁶ and R ⁷ may be, for example, in common: - (CH ₂ J ₄ -, - (CH ₂₎ S-, - (CH ₂₎ _6, - (CH ₂₎ ₇ -, -CH (CH ₃₎ -CH ₂ -CH ₂ - CH (CH ₃ ) - or -CH (CHS) -CH ₂ -CH ₂ -CH ₂ -CH (CH ₃ ) -. Examples of suitable regulators are furthermore alkylaromatic compounds, for example toluene, ethylbenzene or one or more isomers of xylene. Examples of suitable regulators are also paraffins such as isododecane (2,2,4,6,6-pentamethylheptane) or isooctane.

As initiators for the radical polymerization, the customary free radical initiators such as organic peroxides, oxygen or azo compounds can be used. Also mixtures of several radical starters are suitable.

Suitable peroxides selected from commercially available substances are didecanoyl peroxide, 2,5-dimethyl-2,5-di (2-ethylhexanoylperoxy) hexane, tert-amyl peroxy-2-ethylhexanoate, dibenzoyl peroxide, tert-butyl peroxy-2-ethylhexanoate, tert Butyl peroxydiethylacetate, tert-butyl peroxydiethyl isobutyrate, 1,4-di (tert-butylperoxycarbonyl) cyclohexane as mixture of isomers, tert-butyl perisononanoate, 1,1-di- (tert-butylperoxy) -3,3,5-trimethylcyclohexane , 1, 1 -Di-

(tert-butylperoxy) cyclohexane, methyl isobutyl ketone peroxide, tert-butyl peroxyisopropyl carbonate, 2,2-di- (tert-butylperoxy) butane or tert-butyl peroxyacetate; tert-butyl peroxybenzoate, di-tert-amyl peroxide, dicumyl peroxide, the isomeric di- (tert-butylperoxyisopropyl) benzenes, 2,5-dimethyl-2,5-di-tert-butylperoxyhexane, tert-butylcumyl peroxide, 2, 5-dimethyl-2,5-di (tert-butylperoxy) -hex-3-yne, di-tert-butyl peroxide, 1,3-diisopropylbenzene monohydroperoxide, cumene hydroperoxide or tert-butyl hydroperoxide; or dimeric or trimeric ketone peroxides of the general formula IV a to IV

IV a IV b IV c

The radicals R ⁸ to R ^{13 are} identical or different and are selected from C 1 -C 6 -alkyl, such as methyl, ethyl, n-propyl, isopropyl, n-butyl, sec-butyl, isobutyl, tert-butyl , n-pentyl, sec-pentyl, iso-pentyl, n-hexyl, n-heptyl, n-octyl; preferably linear C 1 -C 6 -alkyl, such as methyl, ethyl, n-propyl, n-butyl, n-pentyl, n-hexyl, more preferably linear C 1 -C ₄ -alkyl, such as methyl, ethyl, n-propyl or n-butyl, most preferred is methyl and ethyl;

C ₆ -C 4 aryl such as phenyl, 1-naphthyl, 2-naphthyl, 1-anthryl, 2-anthryl, 9-anthryl, 1-phenanthryl, 2-phenanthryl, 3-phenanthryl, 4-phenanthryl and 9-phenanthryl Phenyl, 1-naphthyl and 2-naphthyl, more preferably phenyl. Peroxides of the general formulas IV a to IV c and processes for their preparation are known from EP-A 0 813 550.

As peroxides, di-tert-butyl peroxide, tert-butyl peroxypivalate, tert-butyl peroxyisononanoate or dibenzoyl peroxide or mixtures thereof are particularly suitable. As an azo compound, azobisisobutyronitrile ("AIBN") is mentioned as an example Radical starters are metered in amounts customary for polymerizations.

Many commercially available organic peroxides are added to so-called phlegmatizers before they are sold to make them more manageable. For example, white oil or hydrocarbons, in particular isododecane, are suitable as phlegmatizers. Under the conditions of high pressure polymerization, such phlegmatizers may have a molecular weight regulating effect. For the purposes of the present invention, the use of molecular weight regulators should be understood to mean the additional use of further molecular weight regulators beyond the use of phlegmatizers.

The quantitative ratio of the comonomers at the dosage usually does not correspond exactly to the ratio of the units in the ethylene copolymer waxes used according to the invention, since ethylenically unsaturated carboxylic acids are generally more readily incorporated into ethylene copolymer waxes than ethylene.

The comonomers are usually dosed together or separately.

The comonomers can be compressed in a compressor to the polymerization pressure. In another embodiment of the method according to the invention, the comonomers are first brought by means of a pump to an elevated pressure of for example 150 to 400 bar, preferably 200 to 300 bar and in particular 260 bar and then with a compressor to the actual polymerization.

The polymerization may optionally be carried out in the absence and in the presence of solvents, with mineral oils, white oil and other solvents present in the reactor during the polymerization and used to quench the radical initiator or initiators not being considered as solvents in the context of the present invention. Suitable solvents are, for example, toluene, isododecane, isomers of xylene.

Ethylene copolymer wax (A) used according to the invention is at least partially neutralized, for example with hydroxide and / or carbonate and / or bicarbonate of alkali metal, for example sodium hydroxide, potassium hydroxide, sodium carbonate, potassium carbonate, sodium bicarbonate, potassium bicarbonate, lithium hydroxide, or preferably with one or more amines such as ammonia and organic amines such as alkylamines, N-alkylethanolamines, alkanolamines and polyamines. Examples of alkylamines are: triethylamine, diethylamine, ethylamine, trimethylamine, dimethylamine, methylamine, piperidine, morphine-Nn. Preferred amines are monoalkanolamines, N, N-dialkylalkanolamines, N-

Alkylalkanolamines, dialkanolamines, N-alkylalkanolamines and trialkanolamines having in each case 2 to 18 C atoms in the hydroxyalkyl radical and optionally in each case 1 to 6 C atoms in the alkyl radical, preferably 2 to 6 C atoms in the alkanol radical and optionally 1 or 2 C atoms in the alkyl radical , Very particular preference is given to ethanolamine, diethanolamine, triethanolamine, methyldiethanolamine, n-butyldiethanolamine, N ₁ N-

Dimethylethanolamine and 2-amino-2-methylpropanol-1. Very particular preference is given to ammonia and N, N-dimethylethanolamine. Examples of polyamines are: ethylenediamine, tetramethylethylenediamine (TMEDA), diethylenetriamine, triethylenetetramine.

In one embodiment of the present invention, ethylene copolymer wax (A) used in the present invention is partially neutralized, i. at least one third, preferably at least 60 mol% of the carboxyl groups and, for example, up to 99 mol% of the ethylene copolymer wax (s) are neutralized.

In one embodiment of the present invention, ethylene copolymer wax (A) used in the present invention is quantitatively neutralized.

For carrying out the process according to the invention, at least one further wax (B) is used, which is different from ethylene copolymer wax (A) and is also referred to as wax (B) in the context of the present invention.

Examples of suitable waxes (B) are natural waxes such as, for example, beeswax, carnauba wax, candelilla wax, bark wax, ouricouria wax, sugarcane wax, montanic acid and ester wax, raw montan wax and in particular synthetic waxes such as Fischer-Tropsch waxes, low-pressure polyethylene waxes, For example, prepared with the aid of Ziegler-Natta catalysts or metallocene catalysts, further partially oxidized low-pressure polyethylene waxes having an acid number in the range of 1 to 150 mg KOH / g wax, determined according to DIN 53402, wherein low-pressure polyethylene waxes not only homopolymer waxes of ethylene, but also copolymers of polyethylene with a total of up to 20 wt .-% comonomer such as propylene, 1-butene, 1-pentene, 1-hexene, 1-octene, 1-decene or 1-dodecene and in particular paraffin waxes and Isoparaffin waxes, for example, crude paraffins (crude paraffin waxes), guadhrates, deoiled crude paraffins (deoiled crude paraffins) fin waxes), semi or fully refined paraffins (semi or fully refined paraffin waxes) and bleached paraffins (bleached paraffin waxes). Under paraffin waxes are related to the present Invention especially at room temperature solid, in the range of 40 to 80 ⁰ C, preferably 50 to 75 ° C melting paraffins understood, ie saturated hydrocarbons, branched or unbranched, cyclic or preferably acyclic, individually or preferably as a mixture of several saturated hydrocarbons. Paraffin waxes in the context of the present invention are preferably composed of saturated hydrocarbons having 18 to 45 carbon atoms, isoparaffins in the context of the present invention are preferably composed of saturated hydrocarbons having 20 to 60 carbon atoms.

In a specific embodiment of the present invention, as wax (B) other than ethylene copolymer wax (A), a mixture of paraffin wax and partially oxidized polyethylene wax obtainable, for example, by partial oxidation of high pressure or low pressure polyethylene wax is prepared , having an acid number in the range of 1 to 150 mg KOH / g wax, determined according to DIN 53402. If a mixture of paraffin wax and partially oxidized low-pressure polyethylene wax having an acid number in the range of 1 to 150 mg KOH / g wax desires weight ratios in the range of 1:99 to 99: 1, in particular 1: 9 to 9: 1.

In a specific embodiment of the present invention, as wax (B) other than ethylene copolymer wax (A), a mixture of paraffin wax and montan ester wax is used, for example in a weight ratio in the range from 1:99 to 99: 1, in particular 1: 9 to 9: 1.

For carrying out the process according to the invention, it is furthermore possible optionally to use at least one surfactant (C), preferably a nonionic surfactant.

Common nonionic surfactants are, for example, ethoxylated mono-, di- and tri-alkylphenols (degree of ethoxylation: 3 to 50, alkyl radical: C ₄ -C ₂ ), ethoxylated fatty alcohols (degree of ethoxylation: 3 to 80, preferably 10 to 20 ; alkyl radical: C ₈ to C ₃ 6, preferably C ₆ -C ₈₎ and ethoxylated oxoalcohols (degree of ethoxylation: 3 to 80; alkyl radical: -C Css). Examples are the Lutensol ^® brands from BASF Aktiengesellschaft and the Triton ^® grades from Union Carbide.

For carrying out the process according to the invention, it is furthermore possible optionally to use at least one solid in particulate form (D), preferably with an average diameter in the range from 10 nm to 300 nm, particularly preferably in the range from 50 to 250 nm. Particularly suitable examples of solids in Particulate form (D) are alumina, silica gel, in particular fumed silica gel, aluminosilicate, polyethylene and polypropylene. In a specific embodiment of the present invention, it is possible to use at least one montan wax (E), preferably at least one montan acid wax, particularly preferably a resin-free montanic acid wax for carrying out the coating according to the invention, montan wax (E) and in particular montan wax preferably in at least partially neutralized form used and selected for at least partial neutralization of suitable bases from the abovementioned bases.

In one embodiment of the present invention, an aqueous dispersion or emulsion is used to carry out the process according to the invention, which in addition to ethylene copolymer wax (A) in at least partially neutralized form and at least one wax (B); which is different from ethylene copolymer wax (A), and optionally surfactant (C), optionally at least one solid in particulate form (D) and optionally at least one montan wax (E).

To carry out the process according to the invention, it is customary to treat, preferably coat, the surface to be coated with at least one aqueous dispersion or emulsion, the at least one ethylene copolymer wax (A), at least one further wax (B); which is different from ethylene copolymer wax (A), optionally containing at least one preferably nonionic surfactant (C), optionally at least one solid in particulate form (D) and optionally at least one montan wax (E).

In one embodiment of the present invention, aqueous dispersion or emulsion used according to the invention has a solids content in the range from 1 to 70% by weight, preferably from 10 to 65% by weight.

In one embodiment of the present invention, the aqueous dispersion or emulsion used according to the invention contains from 0.1 to 99.9% by weight, preferably from 1 to 99% by weight, particularly preferably from 30 to 70

% By weight of ethylene copolymer wax (A),

0.1 to 99.9 wt .-%, preferably 1 to 99 wt .-%, particularly preferably 30 to 70

Wt% further wax (B) other than ethylene copolymer wax (A),

0 to 20 wt .-%, preferably 0.1 to 15 wt .-% of surfactant (C), 0 to 15 wt .-%, preferably 0.1 to 10 wt .-% solid in particulate form (D),

0 to 20 wt .-%, preferably 0.1 to 15 wt .-% montan wax (E), wherein in wt .-% in each case based on the solids content of the invention used aqueous dispersion or emulsion.

The process according to the invention can be carried out, for example, by applying ethylene copolymer wax (A) to the surface to be coated, further wax (B) which is different from ethylene copolymer wax (A), optionally surfactant (C), optionally solid in particulate form (D) and optionally montan wax (E), for example in the form of an aqueous emulsion or dispersion applies. The application can be done for example by applying such as spraying, knife coating, brushing or dipping.

The application is preferably in the form of a preferably coherent film, which may have a wet thickness of, for example, 1 to 300 μm, preferably 5 to 100 μm.

After application, it is possible to dry, for example thermally, at temperatures in the range from 35 to 110 ^° C. However, it is also possible to dry at room temperature. It is also possible to dry by known methods of freeze-drying.

After drying, the applied preferably coherent film may have, for example, a thickness in the range from 0.5 to 75 μm, preferably from 1 to 40 μm and particularly preferably up to 25 μm.

Another object of the present invention is the use of ethylene copolymer waxes (A) according to the inventive method described above.

Another object of the present invention are coated surfaces, obtainable by the inventive method described above. Coated surfaces according to the invention are characterized by overall advantageous properties, for example high water-repellent behavior, good optical properties and high film resistance, in particular as regards durability, especially due to good durability or adhesion to the respective coated article.

In many cases, especially when coated surfaces according to the invention comprise wood, it is observed that scratches in the coating according to the invention heal with time. Thus, a certain self-healing effect is observed, which increases the lifetime of coatings according to the invention.

Another aspect of the present invention are articles comprising at least one coated surface according to the invention. Inventive objects are characterized, for example, by their high durability against water or substances dissolved in water.

A further subject of the present invention are aqueous formulations, for example dispersions and emulsions, containing at least one ethylene copolymer. polymer wax (A) and at least one further wax (B), which is different from ethylene copolymer wax (A), and optionally at least one surfactant (C). Aqueous formulations according to the invention may contain at least one solid in particulate form (D) and / or at least one montan wax (E).

In one embodiment of the present invention, the aqueous formulation according to the invention has a solids content in the range from 1 to 70% by weight, preferably from 10 to 65% by weight.

In one embodiment of the present invention, aqueous formulation according to the invention comprises:

0.1 to 99.9 wt .-%, preferably 1 to 99 wt .-%, particularly preferably 10 to 70

% By weight of ethylene copolymer wax (A),

From 0.1 to 99.9% by weight, preferably from 1 to 99% by weight, particularly preferably from 10 to 70% by weight, of further wax (B) which is different from ethylene copolymer wax (A),

0 to 20% by weight, preferably 0.1 to 15% by weight of surfactant (C),

0 to 15 wt .-%, preferably 0.1 to 10 wt .-% solid in particulate form (D),

0 to 20 wt .-%, preferably 0.1 to 15 wt .-% montan wax (E),

wherein in wt .-% in each case based on the solids content of inventive aqueous formulation.

In one embodiment of the present invention, ethylene copolymer wax (A) is selected from those ethylene copolymer waxes incorporated in copolymerized form as comonomers

(B) 60 to 85 wt .-%, preferably 65 to 81 wt .-%, particularly preferably 66 to 75 wt .-% of ethylene, and such ethylene copolymer waxes containing polymerized

In one embodiment of the present invention, the formulation according to the invention may comprise more basic substance (s), in particular amine, than necessary for complete neutralization of ethylene copolymer wax (A), for example an excess of up to 100 mol%, preferably up to 50 mol%. According to the invention aqueous formulations are particularly well suited for carrying out the process according to the invention.

A further subject of the present invention are processes for the preparation of aqueous formulations according to the invention, hereinafter also referred to as inventive production process.

The preparation process according to the invention can be carried out, for example, by reacting ethylene copolymer wax (A) in at least partially neutralized form, at least one further wax (B) other than ethylene copolymer wax (A), water and optionally at least one surfactant (C) any order mixed together.

In one embodiment of the present invention, the preparation process according to the invention is carried out by reacting ethylene copolymer wax (A) in at least partially neutralized form, at least one further wax (B) other than ethylene copolymer wax (A), water and optionally at least one surfactant ( C) at a temperature lower than the melting point of wax (B).

In the abovementioned embodiment of the production process according to the invention, the mixing can be carried out, for example by rapid stirring, for. B. with 5,000 to 20,500 U / min, preferably with at least 8,000 U / min, for example with UITra Turrax stirrer.

To carry out the above-mentioned embodiment of the production process according to the invention, wax (B) other than ethylene copolymer wax (A) is preferably used in the form of an aqueous dispersion comprising one or more waxes (B) and one or more preferably nonionic surfactants (C) contains.

After carrying out the abovementioned embodiment of the preparation process according to the invention, formulations according to the invention having a bimodal particle diameter distribution can preferably be obtained.

In another variant of the present invention, the preparation process according to the invention is carried out by reacting ethylene copolymer wax (A) in at least partially neutralized form with at least one further wax (B) other than ethylene copolymer wax (A) and with water at one temperature which exceeds the melting point of wax (B) and ethylene copolymer wax (A). One can do without the use of surfactant (C). The abovementioned variant can be carried out, for example, by reacting ethylene copolymer wax (A) preheated to a temperature in the range from 60 to 98 ° C. in at least partially neutralized form with at least one molten wax (B) obtained from ethylene copolymer wax (A). is different, mixed in water, in particular emulsified.

After carrying out the abovementioned variant of the preparation process according to the invention, formulations according to the invention having a monomodal particle diameter distribution can preferably be obtained.

In another variant of the present invention, the preparation process according to the invention is carried out by reacting ethylene copolymer wax (A) in unneutralized form with at least one further wax (B) in molten form, which is different from ethylene copolymer wax (A) in water at Temperature mixed and in particular emulsified, which is above the melting point of wax (B), and at the same time neutralized with the mixing or emulsifying or subsequently at least partially with base.

To carry out the abovementioned variant of the invention Herstellstellvorgang starting from one or more of the above-described ethylene copolymer waxes (A) in non-neutralized form. This or these are placed in a vessel such as a flask, autoclave or kettle, add wax (B), water and one or more bases and heated ethylene copolymer wax (A), water and one or more bases and wax (B). , wherein the order of addition of water and the addition of base, wax (B) and other ingredients is arbitrary. If the temperature is above 100 ⁰ C, it is advantageous to work under elevated pressure and to choose the vessel accordingly. Homogenize the resulting emulsion, for example by mechanical or pneumatic stirring or by shaking. It is heated to a temperature above the melting point of wax (B) and advantageously to a temperature above the melting point of ethylene copolymer wax (A). Advantageously, heating to a temperature which is at least 5 ° C, particularly advantageously at a temperature at least 10 ⁰ C above the melting point of ethylene copolymer (A).

If a plurality of different ethylene copolymer waxes (A) are used, the mixture is heated to a temperature which is above the melting point of the ethylene copolymer wax (A) which melts at the highest temperature. In the case where one uses several different ethylene copolymer waxes (A), it is advantageous to heat to a temperature which is at least 5 ° C. above the melting point of the ethylene copolymer wax (A) melting at the highest temperature. It is particularly advantageous to heat in the case that several different ethylene copolymer waxes (A) used, to a temperature which is at least 10 ⁰ C above the melting point of the melting at the highest temperature ethylene copolymer wax (A).

Subsequently, the aqueous formulation thus prepared is allowed to cool.

In another variant of the present invention, the preparation process according to the invention is carried out by dispersing ethylene copolymer wax (A) in unneutralized form with at least one further wax (B), at least one base and water, for example in a mill, in particular a ball mill. or a shaking apparatus, for example a Skandex. Preferably, no further surfactant (C) is used in this variant.

To carry out the abovementioned variant, it is also possible to add grinding aids, for example glass or steel balls.

In carrying out the above-mentioned variant of the present invention, the mixture of ethylene copolymer wax (A), wax (B), base and water can be heated so that, for example, the melting point of wax (B) is exceeded.

Aqueous formulations according to the invention are characterized by good storage stability and can be used well in the above-described process according to the invention for coating surfaces.

The invention will be explained by working examples.

working examples

General: To determine the hydrophobicity, the contact angle with water was determined in accordance with DIN EN 828: 1997. The tangent method was used to evaluate the experiments (sessile drop).

1. Preparation of Ethylene Copolymer Wax In a high-pressure autoclave as described in the literature (M. Buback et al., Chem. Ing. Tech., 1994, 66, 510), ethylene and methacrylic acid were copolymerized. For this purpose, ethylene (12.0 kg / h) was continuously fed under the reaction pressure of 1700 bar in the high-pressure autoclave. Separately, the amount of methacrylic acid shown in Table 1 was first compressed to an intermediate pressure of 260 bar and then continuously fed using a further compressor under the reaction pressure of 1700 bar in the high-pressure autoclave. Separately, the amount indicated in Table 1 initiator solution consisting of tert-Butyl peroxypivalate (in isododecane, concentration see Table 1), continuously fed under the reaction pressure of 1700 bar in the high-pressure autoclave. Separately, the amount indicated in Table 1 controller, consisting of propionaldehyde in isododecane, concentration see Table 1, first compressed to an intermediate pressure of 260 bar and then continuously fed using a further compressor under the reaction pressure of 1700 bar in the high-pressure autoclave , The reaction temperature was about 220 ^° C. This gave ethylene copolymer wax (A) according to the invention with the analytical data shown in Table 2.

Tractor is the maximum internal temperature of the high-pressure autoclave to understand. Abbreviations: MAS: methacrylic acid, PA: propionaldehyde, ID: isododecane (2,2,4,6,6-pentamethylheptane), PA in ID: solution of propionaldehyde in isododecane, total volume of solution.

PO: tert-butyl peroxypivalate, ECW: ethylene copolymer wax c (PA): concentration of PA in ID in volume percent, c (PO): concentration of PO in ID in mol / l

The conversion refers to ethylene and is given in% by weight

The ethylene copolymer wax A-V6 is a comparative example. TABLE 2 Analytical data of ethylene copolymer wax used according to the invention (A)

The MFR of ethylene copolymer wax A.5 was 10.3 g / 10 min determined at a load of 325 g at a temperature of 160 ^° C.

nb .: not determined.

By "content" is meant the proportion of copolymerized ethylene or MAS in the respective ethylene copolymer wax.

v: dynamic melt viscosity measured at 120 ⁰ C according to DIN 51562,

The content of ethylene and methacrylic acid in the ethylene copolymer used in the invention was determined by NMR spectroscopy or by titration (acid number). The acid number of the ethylene copolymer waxes used according to the invention was determined by titrimetry according to DIN 53402. The KOH consumption corresponds to the methacrylic acid content in the ethylene copolymer wax. The density was determined according to DIN 53479. The melting range was determined by DSC (differential scanning calorimetry, differential thermal analysis) according to DIN 51007 determined.

2. Preparation of dispersions and comparative experiment

In a 2-liter autoclave with anchor stirrer, the amount of ethylene copolymer wax specified in Table 3 according to Example 1 was submitted. The amounts of deionized water indicated in Table 3 and the amine indicated in Table 3 were added and the mixture was heated to 120 ^° C. with stirring. After 15 minutes at 120 ° was cooled within 15 minutes to room temperature. The aqueous dispersions WD 1, WD2, WD3-V or WD4-V were obtained. Table 3: Preparation of dispersions

The "amount NH3" refers to the amount of 25% by weight aqueous ammonia solution.

3. Preparation of formulations according to the invention

Into a 250 ml beaker with Ultra-Turrax, the amount of ethylene copolymer wax (A) indicated in Table 4 was presented in neutralized form according to Example as WD1 or WD2 and heated to 8O ⁰ C. The amounts of deionized water indicated in Table 4 were added and heated to 8O ⁰ C with stirring on a water bath. Thereafter was added paraffin wax (unbranched, melting range 65-70 ⁰ C, average number of carbon atoms per molecule: 40) (B.1) in molten form to. A mixture was obtained. The water bath was removed and the mixture was stirred with the Ultra-Turrax at 9500 rpm until the temperature reached 45 ° C. The formulation according to the invention was obtained according to Table 4.

To prepare formulation F3 according to the invention, the procedure was as described above, but 12% by weight of a fumed silica gel (D.1) (primary particle diameter: 7 nm, average particle diameter 200 nm) was mixed to give the molten paraffin wax (B.1) and thus obtainable mixture of (B.1) and (D.1) to WD-1.

Table 4: Preparation of formulations according to the invention

Note: as surfactant (C.1), a Ci6-Ci8 fatty alcohol mixture (molar ratio 1: 1) reacted with 7 equivalents of ethylene oxide was used. The novel dispersions F1 and F2 were each stored at room temperature. Even after 24 hours of storage, they were still in a dense, homogeneous-looking, strongly foamed state. Only after more than a week, a phase separation was observed, the paraffin wax swam up.

4. Coating of glass

General rule:

On a glass sheet, a film of inventive formulation according to Table 4 was applied with the aid of a doctor blade. The wet film each had a thickness of 60 μm. The mixture was then dried for 30 minutes at a drying temperature according to Table 5 and the quality of the film was assessed.

Table 5: Coating of glass

Note: The gloss was always judged at 85 °. As a reference, the data of an uncoated glass plate are also given. High gloss is undesirable, nb: not determined

5. Preparation of formulations according to the invention by dispersing in a shaking apparatus and coating glass

One prepared a mixture by mixing of

40 g of ethylene copolymer wax A.5

6.8 g of N, N-dimethylethanolamine

40 g (B.1)

113.2 g of distilled water

The resulting mixture was placed in a 500 ml polyethyene bottle in a Skandex type shaker with 900 g steel balls (3 mm diameter) for one hour and dispersed for 45 minutes. The mixture reached a temperature of 90 ⁰ C. This gave inventive aqueous formulation F.5.

Aqueous formulation F.5 according to the invention was stored at room temperature for a period of one week. After 12 hours and even after 72 hours of storage, it was a visually uniform, highly viscous dispersion with a small amount of foam on it. Even after one week of storage, it was a visually uniform, highly viscous dispersion, but on which no foam was observed.

A film of formulation F.5 according to the invention was applied to a glass pane using a doctor blade. The wet film had a thickness of 60 μm. The mixture was then dried for 30 minutes at a drying temperature according to Table 6 and the quality of the film was assessed. For comparison, coated with WD1 or WD2.

Table 6: Coating of glass with inventive formulation F.5 and comparative experiments

Claims

claims

1. A method of coating surfaces using

(A) at least one ethylene copolymer wax, selected from those ethylene copolymer waxes which contain copolymerized as comonomers

(A) 15 to 40 wt .-% of at least one ethylenically unsaturated carboxylic acid and

(B) 60 to 85 wt .-% of ethylene, and those ethylene copolymer waxes which contain copolymerized (a ¹ ) 14.5 to 39.9 wt .-% of at least one ethylenically unsaturated

Carboxylic acid,

(b ¹ ) 60 to 85.4% by weight of ethylene and

(c ') 0.1 to 15 wt .-% of at least one ester of an ethylenically unsaturated carboxylic acid, each in at least partially neutralized form, and

(B) at least one further wax other than ethylene copolymer wax (A).

2. The method according to claim 1, characterized in that at least one ethylenically unsubstituted (a) or (a ') has the general formula I,

where the radicals are defined as follows:

R ¹ selected from hydrogen, unbranched or branched Ci-Cio-alkyl, R ² selected from hydrogen, COOH and unbranched or branched Ci-Cio-alkyl.

3. The method according to claim 1 or 2, characterized in that at least one ester of an ethylenically unsaturated carboxylic acid (c ') has the general formula II,

where the radicals are defined as follows:

R ³ selected from hydrogen, unbranched or branched Ci-Cio-alkyl, R ⁴ selected from hydrogen, unbranched or branched Ci-Cio-alkyl. R ⁵ selected from unbranched or branched Ci-Cio-alkyl or C3-C12

Cycloalkyl.

4. The method according to any one of claims 1 to 3, characterized in that R ^{1 is} methyl.

5. The method according to any one of claims 1 to 4, characterized in that R ^{2 is} hydrogen.

6. The method according to any one of claims 1 to 5, characterized in that the or the ethylene copolymer (A) are at least partially neutralized with basic alkali metal compound or at least one amine.

7. The method according to any one of claims 1 to 6, characterized in that the or the ethylene copolymer (A) are at least partially neutralized with amine, wherein at least one amine is selected from ammonia, N-alkylethanolamines, alkanolamines and polyamines.

8. The method according to any one of claims 1 to 7, characterized in that surfaces are selected from surfaces of metals, lacquered or un-painted, cellulosic substrates, textile, natural and synthetic films and adhesives.

9. The method according to any one of claims 1 to 8, characterized in that at least one wax (B) is selected from paraffin waxes.

10. The method according to any one of claims 1 to 9, characterized in that one surfaces with a film of ethylene copolymer wax (A) and more

Wax (B) which is wet in the range of 1 to 300 microns thick.

11. The method according to any one of claims 1 to 10, characterized in that at least one aqueous emulsion or dispersion containing at least one ethylene copolymer wax (A), at least one further wax (B), which is different from ethylene copolymer wax (A), and optionally at least one surfactant (C), applied to the surface to be coated.

12. Use of at least partially neutralized ethylene copolymer wax (A) by a process according to any one of claims 1 to 11.

13. Coated surfaces obtainable by a process according to one of claims 1 to 11.

14. articles comprising at least one surface according to claim 13.

An aqueous formulation comprising at least one ethylene copolymer wax (A) and at least one further wax (B) other than ethylene copolymer wax (A), and optionally at least one surfactant (C).

16. Process for the preparation of aqueous formulations according to claim 15, characterized in that ethylene copolymer wax (A), at least one further wax (B) other than ethylene copolymer wax (A), water and optionally at least one surfactant (C) in a Temperature mixed, which is below the melting point of wax (B).

A process for the preparation of aqueous formulations according to claim 15, characterized in that ethylene copolymer wax (A) is mixed with at least one further wax (B) other than ethylene copolymer wax (A) in water at a temperature above the melting point of wax (B) lies.

18. Process for the preparation of aqueous formulations according to claim 15, characterized in that ethylene copolymer wax (A) in unneutralized form with at least one further wax (B), which is different from ethylene copolymer wax (A), in water at a temperature which is above the melting point of wax (B) and of ethylene copolymer wax (A), and at the same time as mixing or at least partially neutralized with base.