DE4016999A1 - METHOD FOR PRODUCING A HARDENABLE COMPOSITION, THE HARDENABLE COMPOSITION PRODUCED BY THIS METHOD AND THEIR USE - Google Patents

Description

The present invention relates to a method for Preparation of a curable composition containing a polymer compound containing silyl groups, where the silyl groups by monomeric compounds the general formula

With
R¹ = alkyl, aryl, acyl, aralkyl with 1 to 10 carbon atoms
R² = organic residue with polymerizable double bond or organic residue with reactive group
X = hydrolyzable group
n = 1, 2 or 3
be introduced into the polymer.

Compositions are already known which are characterized by Mixing acid, base, organometallic catalysts u. Ä. with an alkoxysilane group  Acrylate copolymer are produced, and the by crosslinking at a relatively low temperature, d. H. at room temperature up to temperatures of about 100 ° C, can be cured. Such compositions are for example in the international Patent application with the international publication number WO88 / 02010 and in the literature cited in this document described. This from the patent application with the international publication number Compositions known from WO88 / 02010 stand out when used as a paint, in particular by a good petrol and solvent resistance of the cured Coatings should, however, in particular the curing speed and the Erichsen deepening and cross-cut values of the resulting Coatings can be further improved.

Furthermore, for example, from the international Patent application with the international publication number WO88 / 07556 compositions known those activated from compounds (I) with at least two Double bonds and compounds (II) that contain at least two active hydrogen atoms, getting produced. These compositions can also by crosslinking at relatively low temperatures, d. H. at room temperature up to temperatures of about 100 ° C, cured. This from the patent application with the international publication number Compositions known from WO88 / 07556 are characterized by short drying times as well due to very good resistance to solvents and petrol of the coatings made from them. The visual appearance, the gloss and the Cross cut values of the resulting coating however, should be further improved.  

Finally, from DE-PS 37 16 417 curable additives known from a copolymer known as monomeric components an oxirane-containing vinyl monomer and contains an alkoxysilane-containing vinyl monomer, and an aluminum chelate compound and / or a zirconium chelate compound be produced as a crosslinker and they also cure at a low temperature.

The present invention is therefore the object based on a method for producing a curable To provide composition at which Compositions obtained at low Temperatures can harden and therefore preferably can be used in car refinishing, largely are isocyanate-free and lead to coatings, which has good resistance to petrol and solvents, improved Erichsen cupping and cross-cut values, a good visual appearance and a high Shine and the best possible weather resistance exhibit.

Surprisingly, this task is accomplished through a process of the type mentioned solved that is marked that

• 1. at least one polymer A, the monomeric compounds of the formula (I) and monomeric compounds having at least one group with active hydrogen atoms of the type or contains -CH₂- copolymerized,
  or
• 2. a mixture of at least one polymer B, which contains copolymerized monomeric compounds of the formula (I), and at least one polymer C, which contains monomeric compounds having at least one group with active hydrogen atoms of the type or contains -CH₂- copolymerized,
• 3. at least one organic solvent,  
• 4. optionally at least one monomeric and / or oligomeric Connection that is more than one versus active Has hydrogen atoms reactive group, as Crosslinking agents,
• 5. If necessary, pigments and / or fillers and
• 6. If necessary, auxiliaries and additives

are mixed and optionally dispersed and that before Application a mixture of at least one catalyst for curing over the silyl groups and at least one catalyst for curing the groups with active hydrogen atoms added becomes.

The present invention also provides those that can be produced by the method according to the invention curable compositions and their use.

The following are first those in the invention Process used components explained in more detail.

Preference is given to the preparation of the curable compositions Binder based on acrylic copolymers used. Acrylate copolymers are suitable, which are both silyl groups in one molecule as well as groups with active hydrogen atoms of type

or -CH₂- included and further Mixtures of an acrylate copolymer containing silyl groups and an acrylate copolymer with groups with active hydrogen atoms of the type

or -CH₂-.

A method is therefore particularly preferred in that is characterized in that a polymer A is used which is obtainable by copolymerization from

• a) 20 to 50 wt .-%, preferably 30 to 40 wt .-%, a mixture of at least one of the silane monomers (I) with R₂ = organic radical with polymerizable double bond and at least one ethylenically unsaturated monomer with at least one group with active hydrogen atoms of type or -CH₂-,
• b) 0 to 30% by weight, preferably 20 to 25% by weight, at least of a monomer with at least two polymerizable ethylenically unsaturated double bonds,
• c) 0 to 40% by weight, preferably 10 to 20% by weight, at least a vinyl aromatic hydrocarbon,
• d) 20 to 80% by weight, preferably 30 to 70% by weight, at least one alkyl ester of acrylic and / or Methacrylic acid and
• e) 0 to 20 wt .-%, ethylenically unsaturated monomers without active hydrogen groups, where the sum of the parts by weight of components a to e is 100% by weight in each case.

A method is also preferred which is characterized in that is that a polymer B is used which is available through copolymerization of

• f) 20 to 50% by weight, preferably 30 to 40% by weight, at least one silane monomer (I) with R₂ = organic Remainder with polymerizable double bond,
• g) 0 to 30% by weight, preferably 20 to 25% by weight, at least one monomer with at least two polymerizable ethylenically unsaturated double bonds,  
• h) 0 to 40% by weight, preferably 10 to 20% by weight, at least a vinyl aromatic hydrocarbon,
• i) 20 to 80% by weight, preferably 30 to 70% by weight, at least one alkyl ester of acrylic and / or Methacrylic acid and
• j) 0 to 20% by weight of ethylenically unsaturated monomers without active hydrogen groups, where the sum of the parts by weight of the components f to j is 100% by weight in each case, and that a polymer C is used, which is available through Copolymerization of
• k) 20 to 50% by weight, preferably 30 to 40% by weight, of at least one ethylenically unsaturated monomer having at least one group with active hydrogen atoms of the type or -CH₂-,
• l) 0 to 30 wt .-%, preferably 20 to 25 wt .-%, at least of a monomer with at least two polymerizable ethylenically unsaturated double bonds,
• m) 0 to 40% by weight, preferably 10 to 20% by weight, at least a vinyl aromatic hydrocarbon,
• n) 20 to 80% by weight, preferably 30 to 70% by weight, at least one alkyl ester of acrylic and / or Methacrylic acid and
• o) 0 to 20% by weight of ethylenically unsaturated monomers without active hydrogen groups, where the sum of the parts by weight of the components k to o is 100% by weight in each case.

The silyl groups are thereby in the copolymers introduced that the copolymers using of ethylenically unsaturated monomers (component a or f) the general formula  

With
R¹ = alkyl, aryl, acyl, aralkyl with 1 to 10 carbon atoms
R² = organic residue with polymerizable double bond
X = hydrolyzable group
n = 1, 2 or 3
getting produced. The hydrolyzable group X can be, for example, a halogen radical, an alkoxy radical, an acyloxy radical, a mercapto radical or an alkenyloxy radical. Suitable examples of the silane monomers are listed below:
γ-acryloxyethyltriethoxysilane, γ-methacryloxyethyl triethoxysilane, γ-methacryloxypropyltrimethoxysilane, γ-methacryloxypropyltriethoxysilane, γ-acryloxypropyl trimethoxysilane, γ-methacryloxybutyltriethoxysilane, γ-acryloxypropyl
such as

The examples in DE-PS 37 16 417 are also suitable for the compounds named monomer A. Especially preferred as silane monomer (I) γ-methacryloxypropyltrimethoxysilane used.

For the introduction of groups with active hydrogen atoms of type

or -CH₂- are all ethylenic unsaturated compounds suitable, the groups contain with active hydrogen (component a or k). For example, as monomers C-H-acidic groups monomers based on acetoacetic acid, Cyanoacetic acid, malonic acid, cyclopentanone carboxylic acid, Methane tricarboxylic acid and cyclohexanone carboxylic acid suitable. Acetoacetate groups are preferred or malonic or methane tricarboxylic acid Monomers used.

Acetoacetoxyethyl methacrylate, for example, is suitable; Adducts of hydroxyalkyl esters of acrylic and methacrylic acid with methyl acetoacetate, ethyl acetoacetate, n-propylacetoacetate, iso-propylacetoacetate, n-butylacetoacetate, iso-butylacetoacetate and preferred with t-butyl cetoacetate; Adducts of hydroxyalkyl esters acrylic and methacrylic acid on cyanoacetic acid, Malonic acid, cyclopentanone carboxylic acid, methane tricarboxylic acid and cyclohexanone carboxylic acid or its Derivatives.

Acetoacetoxyethyl methacrylate is preferably used.

To produce the used as a binder Acrylate copolymers can also be used as monomers vinyl aromatic hydrocarbons are used (Components c or h or m). Monovinyl aromatic are preferred Compounds with 8 to 9 carbon atoms  used per molecule. Examples of suitable ones Compounds are styrene, vinyl toluenes, α-methylstyrene, chlorostyrenes, o-, m- or p-methylstyrene, 2,5-dimethylstyrene, p-methoxystyrene, p-tert-butylstyrene, p-dimethylaminostyrene, p-acetamidostyrene and m-vinylphenol. To be favoured Vinyl toluenes and styrene in particular are used.

Also used to manufacture the as a binder used acrylic copolymers alkyl esters Acrylic and methacrylic acid used (component d or i or n). Examples include methyl (meth) acrylate, Ethyl (meth) acrylate, propyl (meth) acrylate, Butyl (meth) acrylate, isopropyl (meth) acrylate, Isobutyl (meth) acrylate, pentyl (meth) acrylate, Isoamyl (meth) acrylate, hexyl (meth) acrylate, Cyclohexyl (meth) acrylate, 2-ethylhexyl (meth) acrylate, Octyl (meth) acrylate, 3,5,5-trimethylhexyl (meth) acrylate, Decyl (meth) acrylate, dodecyl (meth) acrylate, hexadecyl (meth) acrylate, Octadecyl (meth) acrylate, octadecenyl (meth) acrylate.

Furthermore, for the production of as binders Acrylate copolymers used also with monomers at least two polymerizable ethylenically unsaturated Double bonds are used (component b or g or l). Connections can be advantageous the general formula

With
R = H, CH₃ or alkyl
X = O, NH, S
n = 2 to 8
be used. Examples of such compounds are hexanediol diacrylate, hexanediol dimethacrylate, glycol diacrylate, glycolediamethacrylate, butanediol diacrylate, butanediol dimethacrylate, trimethylolpropane triacrylate and trimethylolpropane trimethylacrylate. Divinylbenzene is also suitable. Combinations of these polyunsaturated monomers can of course also be used.

Furthermore, the component can have at least two Double bonds advantageously one with an unsaturated, containing a polymerizable double bond Alcohol esterified polycarboxylic acid or a unsaturated esters esterified with an unsaturated alcohol Be monocarboxylic acid.

Furthermore, can advantageously be used as such a component Reaction product of a polyisocyanate and an unsaturated Alcohol or an amine can be used. The reaction product is an example of this from one mole of hexamethylene diisocyanate and two moles Allyl alcohol or the reaction product from isophorone diisocyanate and called hydroxyethyl acrylate.

Another advantageous component of this type is a diester of polyethylene glycol and / or polypropylene glycol with an average molecular weight of less than 1500, preferably less than 1000, and Acrylic acid and / or methacrylic acid.

Coming as a monomer with at least two double bonds furthermore reaction products from a carboxylic acid with a polymerizable, olefinically unsaturated Double bond and glydidyl acrylate and / or Glycidyl methacrylate and reaction products from  Dicarboxylic acids with glycidyl acrylate and / or glydidyl methacrylate in question. Such multiple ethylenic unsaturated monomers should, however, according to the invention can only be used in small proportions as they Contain hydroxyl groups with the silane monomers (I) can react. This also applies to multiple ethylenically unsaturated monomers made from diepoxide compounds and ethylenically unsaturated monomers with a primary or secondary amino group because these products are also hydroxyl groups contain.

The selection of the ethylenically unsaturated neutral monomers (Component e or j or o) is not special critical. These can be selected from the Group of alkyl esters α, β-unsaturated carboxylic acid, except alkyl esters of acrylic and methacrylic acid, Alkoxyethyl acrylates, aryloxyethyl acrylates and the corresponding methacrylates u. Ä.

Examples include butoxyethyl acrylate, butoxyethyl methacrylate, Phenoxyethyl (meth) acrylate, acrylonitrile, Methacrylonitrile, vinyl acetate, vinyl chloride as well as the alkyl esters of maleic, fumaric, croton, Isocrotonic and itaconic acid, such as. B. the methyl, Ethyl, propyl, butyl, isopropyl, isobutyl, t-butyl, pentyl, isoamyl, hexyl, cyclohexyl, 2-ethylhexyl, octyl, 3,5,5-trimethylhexyl, decyl, Dodecyl, hexadecyl, octadecyl and octadecenyl esters of these acids. Other monomers can be used unless they become undesirable properties of the copolymer.

The radical polymerization to produce the silyl group-containing and / or containing C-H-acidic groups Polymerisate in an organic solvent  at temperatures of 80-130 ° C, preferably 90-120 ° C. Advantageously radical polymerization becomes Preparation of the polymer carried out so that a Solution of the polymer with a solids content of 40-65% by weight results.

As a solvent for radical polymerization come non-reactive solvents, such as Esters, ethers, hydrocarbons, alcohols and Ketones in question.

The polymerization reaction is carried out in the presence of a Initiator and possibly carried out in the presence of a controller. The controller is then usually in one Amount of at least 2% by weight, preferably at least 4% by weight, based on the total weight of the monomers used. To be favoured Polymerization regulator without active OH or NH groups, such as B. mercaptoethanol and mercaptosilanes, used. For example, for suitable regulators the in the international patent application with the international publication number WO88 / 02010 described connections.

It turns out that often only overruled regulators for certain combinations of those to be polymerized Monomers are suitable.

If, for example, diacrylates or Dimethyl acrylates of the general formula  

With
R = H, CH₃ or alkyl
X = O, NH, S
n = 2 to 8
in a proportion of more than 10% by weight, based on the total weight of all monomers, the polymerization should be carried out using more than 6% by weight, based on the total weight of the monomers, of mercaptoethyltriethoxysilane and / or mercaptopropylmethyldimethoxysilane, if appropriate together with other mercapto compounds, in a temperature range between 100 ° C and 120 ° C.

If more than 10 wt .-% divinylaromatics, such as Divinylbenzene, together with the monomers should be copolymerized, preferably as a regulator more than 10% by weight, based on the monomer weight, Mercaptoethyltriethoxysilane and / or Mercaptopropylmethyldimethoxysilane can be used, to prevent gelation of the copolymer.

Azo initiators are preferably used as initiators, such as azobisisobutyronitrile and Azobis (isovaleronitrile) in question. With a low proportion on polyunsaturated polyunsaturated Monomers can also use peroxy esters as initiators be used. As examples of this tert-Butylperoxy-2-ethylhexanoate called. Of course can also use azo initiators with reactive Silicone groups can be used. These are in one Proportion of 0.01 to 20 parts by weight per 100 parts by weight of the polymerizable monomers used.  

Examples of reactive silicone groups that can be used Azo initiators containing are found in EP-A-1 59 715 and EP-A-1 59 716.

Those produced by the process according to the invention Acrylate copolymers usually have number-average Molecular weights from 1000 to 35,000 im Case of linear, i.e. H. without the use of monomers made with at least 2 double bonds, Copolymers and in the case of branched acrylate copolymers number average molecular weights from 2,000 to 50,000.

To prepare the curable compositions acrylate copolymers are particularly preferred as binders used in the copolymerization a mixture of silane monomers (I) and ethylenically unsaturated monomers (II) with at least a group with active hydrogen atoms from Type

or -CH₂- is used. Doing so the mixing ratio of silane monomers (I) to Monomers with -C-H-acidic groups (II) preferred between 10: 1 and 1:10, particularly preferably between 5: 1 and 1: 5 and very particularly preferably between 3: 1 and 1: 2 selected. The using of these bifunctional acrylate copolymers curable compositions stand out due to high gloss, good visual appearance, very good cross-cut and Erichsen indentation values and improved weather resistance. These were made using the monomer mixtures Acrylate copolymers are in the curable Compositions usually in an amount from 20 to 75% by weight, preferably from 40 to 60% by weight, based on the total weight of the curable composition, used.  

A mixture of one is also suitable acrylate copolymer containing silyl groups and one Acrylate copolymer with groups with active hydrogen atoms of type

or -CH₂- good for production the curable composition. The mixing ratio of acrylate copolymer containing silyl groups to the acrylate copolymer with groups with active hydrogen atoms of the type

or -CH₂- is generally between 10: 1 and 1:10, preferably between 5: 1 and 1: 5 and entirely preferably between 3: 1 and 1: 2.

To prepare the curable compositions as silyl groups and / or groups with active hydrogen atoms of type

and / or -CH₂- carrying Polymers other than the preferred acrylate copolymers other known polymers, for example appropriately modified polyester, Polyester acrylates u. suitable.

These resins are also commonly used in one Total amount from 20 to 75% by weight, preferably from 40 up to 60 wt .-%, based on the total weight of the curable compositions used.

For the preparation of the compositions according to the invention the binders may be mixed with a crosslinking agent mixed and dispersed if necessary.

Suitable as crosslinking agents are all compounds which is more than one towards active hydrogen atoms have reactive group.

Monomers and / or are preferred as crosslinking agents oligomeric compounds with more than one ethylenic unsaturated double bond used per molecule.  

The preferred crosslinking agents are relative low molecular weight (number average molecular weight up to about 2000, preferably up to about 1000) di- and Polyacrylates such as B. butanediol diacrylate, hexanediol diacrylate, Trimethylolpropane diacrylate, trimethylolpropane triacrylate, Pentaerythritol diacrylate, Pentaerythritol tetraacrylate, esterified with acrylic acid alkoxylated glycerin, 1.12 dodecyl diacrylate, urethane groups Polyacrylates such as B. Implementation Products from tolylene diisocyanate, acrylic acid and Pentaerythritol and reaction products from isophorone diisocyanate, Acrylic acid and pentaerythritol used. Possibly. the corresponding methacrylates can also be used are preferred, but the more reactive are preferred Acrylates used. The preferred crosslinking agents conveniently contain in statistical mean 2 to 6 acrylic structures per Molecule. The use of the relatively low molecular weight Crosslinking agent enables the formulation of High solids paints.

A crosslinking agent can also be, for example Reaction product from 1 mol of N-methylolacrylamide or 1 mole of N-methylol methacrylamide, 1 mole of a diisocyanate and a hydroxyl-containing synthetic resin will.

Such resins and the manufacture of these Synthetic resins are described in DE-OS 38 43 323.

Di- and polyisocyanates are also crosslinking agents suitable, for example those in the international Patent application with the international publication number WO90 / 00570 described isocyanate group-containing  Crosslinking agent.

Also suitable as crosslinking agents are aldehydes and Suitable aminoplast resins. Examples of suitable ones Aminoplast resins are also in the international Patent application with the international publication number WO90 / 00570.

Of course, it is also possible to use mixtures use different crosslinking agents. Further compounds can also be used as crosslinking agents be different, per molecule active hydrogen have reactive groups.

The crosslinking agent is usually used in such Amounts used that the equivalent ratio of reactive groups of the crosslinking agent to the active Hydrogen atoms of the polymer A or C between 0: 1 and 1.5: 1, preferably between 0.5: 1 and 1: 1 lies. So it is also possible to use curable compositions without the addition of a crosslinking agent to manufacture.

The curable compositions can also usual pigments and fillers in usual amounts, preferably 0 to 60% by weight, based on the total composition, as well as other usual auxiliaries and additives, such as B. leveling agents, silicone oils, Plasticizers such as phosphoric acid esters and phthalic acid esters, viscosity-controlling additives, matting agents, UV absorbers and light stabilizers in usual Amounts, preferably 0.2 to 10 wt .-%, based on the total composition.

This described, according to the inventive method manufactured compositions have no additive  of a crosslinking catalyst is long enough Pot life. Suitable crosslinking catalysts are used too, the coating compositions also cure Humidity at room temperature or slightly higher Temperature quickly out.

A mixture of is used as the crosslinking catalyst at least one catalyst for curing over the Silyl groups and at least one catalyst for the Hardening over the C-H-acidic groups used.

As catalysts for curing over the silyl groups are, for example, tin dibutyl dilaurate, tin dioctyl laurate, Triethylamine, diazabicyclooctane, Amidines such as diazabicycloalkenes, e.g. B. diazabicyclonones, Diazabicycloundecen and low molecular weight, basic Siloxanes with at least one hydrolyzable Group, such as B. 3-aminopropyltriethoxysilane, 3-aminopropyltrimethoxysilane, 3-aminopropyltrismethoxyethoxysilane, 3-aminopropyl-methyl-diethoxysilane, N-2-aminoethyl-3-aminopropyltrimethoxysilane, N-2-aminoethyl-3-aminopropyl-methyldimethoxysilane, N-methyl-3-aminopropyltrimethoxysilane, 3-ureidopropyltriethoxysilane and 3,4,5-dihydroimidazol-1-yl-propyltriethoxysilane; preferably 3,4,5-dihydroimidazol-1-yl-propyltriethoxysilane, further alkali catalysts, such as potassium hydroxide or Suitable sodium hydroxide.

As organic tin compounds which can be used as crosslinking catalysts, compounds with tin-sulfur single or double bonds may also be mentioned, such as, for. B.
(c-C₄H₉) ₂ Sn (SCH₂COO),
(n-C₈H₁₇) ₂ Sn (SCH₂CH₂COO),
(n-C₈H₁₇) ₂ Sn (SCH₂COO CH₂ CH₂ OCO CH₂S),
(n-C₈H₁₇) ₂ Sn (SCH₂COO CH₂ CH₂ CH₂ CH₂ OCO CH₂S),
(n-C₄H₉) ₂ Sn (SCH₂ COO C₈H₁₇-iso) ₂
(n-C₈H₁₇) ₂ Sn (SCH₂ COO C₁₂H₂₅-n) _{2 ′}
(n-C₄H₉) ₂ Sn (SCH₂COO C₈H₁₇-iso) ₂ and
(n-C₈H₁₇) ₂ Sn = S.

There are also mixtures of the above-mentioned tin Sulfur compounds with tin compounds, such as for example with dialkyltin dimaleates, for catalysis suitable. Mixtures of organotin compounds, such as. B. Tin dibutyl dilaurate with the above-mentioned low molecular weight, basic siloxanes and / or thiol groups Siloxanes that are at least one hydrolyzable Group included, such as B. 3-mercaptopropyl triethoxysilane, 3-mercaptopropylmethyl dimethoxysilane and 3-mercaptopropyltrimethoxysilane.

Find other suitable catalysts in EP-A-48461 and in EP-A-63753.

As catalysts for curing over the groups with active hydrogen are e.g. B. Michael catalysts, for example from the group Diazabicyclooctane, amidines such as e.g. B. diazabicycloundecene, organic phosphonium salts, tertiary Phosphines, alkoxides and the like. a. suitable.

The catalysts are advantageously in a total amount of 0.5 to 5% by weight, preferably 1 up to 3% by weight on the binder content, used.  

Those produced by the process according to the invention curable compositions are suitable especially as a coating agent. You can due to the achievable low curing temperatures (Hardening generally at one temperature from room temperature to about 100 ° C) in particular for the refinishing of motor vehicles be used. But they are also for the area automotive serial painting (hardening in generally at temperatures from 120 to 180 ° C) applicable. They can each be used as a clear coat, for example for metallic multi-layer coatings on a conventional or a water-dilutable Basecoat, as well as basecoat, as a one-coat finish as well as a primer and filler material be used. They are preferred used as clear and top coat.

The curable compositions can be sprayed, Flooding, diving, rolling, knife coating or brushing applied to a substrate in the form of a film the film then becomes an adherent Coating is hardened.

The invention is illustrated in the following examples explained in more detail. All parts and percentages are weights unless expressly stated something else is found.

Conventional basecoats used

There have been known, conventional, conventional basecoats based on 15 to 25% by weight of binder, 0.5 to 22% by weight of pigments (incl. Metallic and Effect pigments) and 68 to 82% by weight of solvent used, the binder being a mixture  from 20 to 30% by weight of CAB (35 to 40% by weight of butyryl, 0.8 to 1.8% by weight hydroxyl, viscosity 50-5000 mPas), 45 to 60% by weight polyester, 7 to 20% by weight Melamine resin and 5 to 10 wt .-% polyethylene or copolymerized polyethylene wax with a Melting point of 90 to 120 ° C and the solvent a mixture of 50 to 65% by weight of butyl acetate, 15 to 30% by weight of xylene, 5 to 10% by weight of butyl glycol acetate and 5 to 15% by weight of butanol and the Sum of the parts by weight of the binder components and the sum of the parts by weight of the solvent components is in each case 100% by weight.

The polyester is based on phthalic acid, adipic acid, Neopentylglycol and trimethylolpropane built and has an acid number (solid) of 5 to 20 mgKOH / g, an OH number (solid) from 130 to 170 mgKOH / g and a number average molecular weight from 1200-2500 on. As a melamine resin is a isobutyl etherified melamine formaldehyde resin with a Viscosity of 200-2000 mPa · s (23 ° C, 55% Solution) used.

Comparative Example 1 Preparation of a copolymer containing silyl groups 1

The proportions of the individual monomers, amounts of solvent, Initiator and regulator quantities as well as polymerization temperature, Feed time of the initiator solution and Binder data are shown in Tables 1 and 2. The acrylates were produced in Standard apparatus (4 liter steel reactors) with stirrer, Reflux cooler and inlet vessels. As a solvent was a 1: 1 mixture of xylene and  1-methoxypropyl-2-acetate used.

The solvent mixture was presented, part was used to dissolve the initiator. As an initiator Azobis (isovaleronitrile) was used. As The polymerization regulator was 3-mercaptopropylmethyldimethoxysilane used.

The solvent mixture was indicated on the Polymerization temperature warmed up, the temperature during the entire polymerization period held. The specified monomer mixture (incl. Controller) and the initiator solution were metered in separately.

The feed times for the monomer mixture were (incl. regulator) 3 hours, with the initiator solution 3.5 hours (see Table 2), with the two Inlets were started simultaneously; the inflow took place evenly over the specified time, after The end of the initiator feed was at 2 hours post-polymerized at the indicated polymerization temperature. The amounts of monomers, solvents, etc. are given in T = parts by weight.

The solid values were here as in the following examples in a convection oven after 1 hour determined at 130 ° C. The viscosities were on a cone and plate viscometer (ICI viscometer) determined at 23 ° C.

Production of a clear coat 1

From 76.0 parts of the silyl group-containing described above Copolymer 1, 4.0 parts of a commercially available  Leveling agent (solution of 1 part of a Polysiloxane polyether copolymer in a mixture 79 parts Shellsol®A and 20 parts Xylene), 3.0 parts butyl glycol acetate, 1.0 part a commercial light stabilizer (commercial product ("Tinuvin 292" from Ciba Geigy), 1.0 parts another commercially available sunscreen (Commercial product "Tinuvin 1130" from the company Ciba Geigy), 5.0 parts butanol and 10 parts Shellsol®A is a clear coat 1 is produced by the individual components one after the other Dissolver be stirred.

Then 8.0 parts of a dilution, consisting from 50% by weight of butyl acetate, 10% by weight of gasoline with a boiling range of 135 to 180 ° C, 15% by weight Xylene, 15% by weight Solvent Naphtha®, 5% by weight Methoxypropyl acetate and 5% by weight butyl glycol acetate admitted.

3 parts of a 10% butanolic are used as catalysts Solution of dibutyltin dilaurate, 1.5 parts 4,5-dihydro-1- [3- (triethoxysilyl) propyl] imidazole and 10 parts of a 1% solution of γ-mercaptopropyltrimethoxysilane used in xylene.

Application of the clear coat 1

For comparison, the clear coat 1 - as described in the patent application with the international publication number WO88 / 02010 - was applied to the conventional solvent-based basecoat described above:
Phosphated steel sheets (Bonder 132) are first coated with a commercially available conventional epoxy filler (dry film thickness 36 µm). The conventional basecoats described above were applied to these filled steel sheets in accordance with a dry film thickness of approx. 15 µm and, after a short flash-off time of 15 min, overcoated with the clear coat 1 described above (dry film thickness approx. 50 µm; spray application: presentation of a cloister, 5 min flash-off time , then 1 closed cloister). After a short flash-off time of 20 minutes, the cover layer was then dried together with the base layer. The technical properties of the resulting coatings were then tested. The results are shown in Table 3.

In addition, the clear lacquer was knife-coated on glass panels (Dry film thickness 25-28 µm) and dried. From the resulting coatings hardness and solvent resistance were tested. The results are shown in Table 4.

Comparative Example 2 Preparation of an Acetoacetate Group-Containing Copolymer 2

It is according to that in Comparative Example 1 Point 1.1 specified manufacturing instructions from the in Table 1 listed components and among the in Table 2 conditions contained an acetoacetate group Copolymer 2 produced. As Solvent in the polymerization became a Mixture of 50% xylene and 50% butyl acetate used. Methyl mercaptan was used as the regulator and Initiator Azobis (isovaleronitrile) used.  

Production of a clear coat 2

From 76.7 parts of the acetoacetate group described above Copolymer 2, 12.6 parts of one commercially available alkoxylated tetrafunctional Pentaerythritol acrylic acid ester with a double bond equivalent weight of 145 (commercial product "Monigomer PPTTA" from Hans Rahn & Co, Zurich), 5 parts of ethanol, 4.5 parts of butyl acetate and 1.5 parts of a solution of a commercially available Leveling agent (5 parts polymerized methylpolysiloxane, dissolved in 94 parts of xylene and 1 part Butanol) a clear coat 2 is produced by the individual components one after the other in a dissolver be stirred. Then 2.5 parts a 20% solution of diazabicycloundecene in Ethanol used as a catalyst.

Application of the clear coat 2

Analogously to Comparative Example 1, phosphated Steel sheets (Bonder 132) first with a commercially available conventional epoxy filler (Dry film thickness 50-55 µm) coated. After aging, the conventional one described above became Basecoat according to a dry film thickness of approx. 12-15 µm applied. To a short flash-off time of approx. 20 min Overcoated clear coat 2 described above (Dry film thickness 50-55 µm) and the base layer dried together with the top layer. Then the technical properties are checked the coating. The results are in Table 3 shown. In addition, were analogous to Comparative Example 1 Glass Elevators Made and checked. The results are shown in Table 4.  

Example 1 Preparation of a copolymer containing silyl groups 3

It is according to that in Comparative Example 1 Point 1.1 specified manufacturing instructions from the in Table 1 listed components and among the in Table 2 conditions listed copolymer 3 containing silyl groups. Xylene was used as the solvent. As an initiator tert-butyl perbenzoate was used.

Preparation of an Acetoacetate Group-Containing Copolymers 4

It is according to that in Comparative Example 1 Point 1.1 specified manufacturing instructions from the in Table 1 listed components and among the in Table 2 conditions contained an acetoacetate group Copolymer 4 produced. As Solvent became a mixture of 50% xylene and 50% butyl acetate used. As an initiator Azobis (isovaleronitrile) is used.

Production of a clear coat 3

From 40.2 parts of the above-described copolymer containing acetoacetate groups 4, 4.9 parts of a commercially available alkoxylated tetrafunctional pentaerythritol acrylic acid ester with a double bond equivalent weight of 145 (commercial product "Monigomer PPTTA" from Hans Rahn & Co, Zurich), 3.1 parts of butanol, 1, 25 parts of ethanol, 3.1 parts of butyl acetate, 0.75 part of a solution of a commercially available leveling agent (solution of 5 parts of a polyether-modified methylpolysiloxane in 1 part of butanol and 94 parts of xylene), 2.0 parts of a solution of a further commercially available leveling agent (solution of 1 part of a polysiloxane polyether copolymer in 79 parts of Shellsol®A and 20 parts of xylene), 38.2 parts of the above-described silyl group-containing copolymer 3, 1.5 parts of butylglycol acetate and 5 parts of Shellsol®A, a clear lacquer 3 is produced by adding the individual components in succession be mixed in a dissolver.

1.25 parts of a 20% strength catalyst are used Solution of diazabicycloundecen in ethanol, 1.5 parts a 10% solution of dibutyltin dilaurate in Butanol, 5 parts of a 3% solution of γ-mercaptopropyltrimethoxysilane in xylene and 0.75 parts 4,5-dihydro-1- [3- (triethoxysilyl) propyl -] - imidazole used. With a paint thinner, consisting from 50% by weight of butyl acetate, 10% by weight of gasoline with a boiling range of 135 to 180 ° C, 15% by weight Xylene, 15% by weight Solvent Naphta®, 5% by weight Methoxypropyl acetate and 5% by weight butyl glycol acetate to a viscosity of 18 s in the DIN 4 flow cup set at 23 ° C.

Application of the clear coat 3

The application and curing of the clear coat 3, (Dry film thickness 50-55 µm) is done analogously to Comparative Example 1 on phosphated Steel sheets (Bonder 132), previously with a conventional Epoxy filler (dry film thickness 50-55 µm) and the conventional described above Basecoat (dry film thickness approx. 12-15 µm) were coated. Checking the  technical properties of the coating as well the glass lifts were also carried out analogously to Comparative Example 1. The results are in Tables 3 and 4 summarized.

Example 2 Production of a clear lacquer 4

From 47.6 parts of the acetoacetate group described above Copolymer 4, 3.1 parts of butanol, 1.25 parts ethanol, 3.1 parts butyl acetate, 0.75 parts a solution of a commercially available leveling agent (Solution of 5 parts of a polyether modified Methylpolysiloxane in 1 part butanol and 94 parts Xylene), 2.0 parts of a solution of another commercial leveling agent (solution of 1 part of a polysiloxane polyether copolymer in 79 parts Shellsol®A and 20 parts xylene), 35.7 parts of the above-described silyl group-containing copolymer 3, 1.5 parts of butyl glycol acetate and 5 parts Shellsol®A is a clear coat 4 made by the individual components one after the other with a dissolver be stirred.

1.25 parts of a 20% strength catalyst are used Solution of diazabicycloundecen in ethanol, 1.5 parts a 10% solution of dibutyltin dilaurate in Butanol, 5 parts of a 3% solution of γ-mercaptopropyltrimethoxysilane in xylene and 0.75 parts 4,5-dihydro-1- [3- (triethoxysilyl) propyl -] - imidazole used. With a paint thinner, consisting from 50% by weight of butyl acetate, 10% by weight of gasoline with a boiling range of 135 to 180 ° C, 15% by weight Xylene, 15% by weight Solvent Naphta®, 5% by weight methoxypropylacetate and 5% by weight of butyl glycol acetate  a viscosity of 18 s in the DIN 4 flow cup 23 ° C set.

Application of the clear coat 4

The application and curing of the clear coat 4, (Dry film thickness 50-55 µm) is done analogously to Comparative Example 1 on phosphated steel sheets (Bonder 132), previously with a conventional Epoxy filler (dry film thickness 50-55 µm) and the conventional basecoat described above (Dry film thickness approx. 12-15 µm) coated were. Checking the technical properties the coating and the glass lifts also took place analogous to comparative example 1. The results are summarized in Tables 3 and 4.

Example 3 Production of a silyl and acetoacetate group Copolymer 5

According to the procedure described in Comparative Example 1 under 1.1 Manufacturing instructions given in Table 1 listed components and among those in Table 2 conditions listed a silyl and acetoacetate Copolymer produced. As a solvent was a mixture of 50 parts of xylene and 50 parts of methoxypropyl acetate. As Azobis (isovaleronitrile) was used as the initiator.

Production of a clear lacquer 5

From 84.1 parts of the silyl and copolymer containing acetoacetate groups 5, 5.1 parts of a commercially available alkoxylated tetrafunctional  Pentaerythritol acrylic acid ester with a double binding equivalent weight of 145 (commercial product "Monigomer PPTTA" from Fima Hans Rahn & Co, Zurich), 2.3 parts butanol, 2.3 parts ethanol, 3.7 parts Butyl acetate, 0.70 parts of a solution of a commercially available Leveling agent (solution of 5 parts of a polyether-modified methylpolysiloxane in 1 part Butanol and 94 parts of xylene) and 1.8 parts of a solution another commercially available leveling agent (Solution of 1 part of a polysiloxane polyether copolymer in 79 parts Shellsol®A and 20 parts xylene) a clear coat 5 is produced by the individual Components are mixed in succession with a dissolver will.

1.25 parts of a 20% strength catalyst are used Solution of diazabicycloundecen in ethanol, 5 parts a 10% solution of dibutyltin dilaurate in Butanol, 5 parts of a 3% solution of γ-mercaptopropyltrimethoxysilane in xylene and 0.75 parts 4,5-dihydro-1- [3- (triethoxysilyl) propyl] imidazole used. With a paint thinner consisting of 50% by weight of butyl acetate, 10% by weight of gasoline with a Boiling range from 135 to 180 ° C, 15 wt .-% xylene, 15% by weight of Naphta® solvent, 5% by weight of methoxypropylacetate and 5% by weight of butyl glycol acetate is added to a Viscosity of 18 s in a DIN 4 flow cup at 23 ° C set.

Application of the clear coat 5

The application and curing of the clear coat 5, (Dry film thickness 50-55 µm) is done analogously to Comparative Example 1 on phosphated steel sheets (Bonder 132), previously with a conventional Epoxy filler (dry film thickness 50-55 µm)  and the conventional basecoat described above (Dry film thickness approx. 12-15 µm) coated were. Checking the technical properties the coating and the glass lifts also take place analogous to comparative example 1. The results are summarized in Tables 3 and 4.

Examples 4 and 5

Analogously to Example 3, the clear coats 6 and 7 manufactured, which differs from the clear coat 5 of Example 3 only by a different salary of crosslinking agents ("Monigomer PPTTA" from the company Hans Rahn & Co, Zurich) differentiate. The Composition of these clear coats 5 to 7 is in Table 5 compiled. The application and Curing of these clear coats and testing of resulting coating takes place analogously to Example 3. The test results of Clearcoat coatings are shown in Table 6, which is the Glass elevators shown in Table 7.

Examples 6 to 8

Analogously to Example 3, the clear coats 8 to 10 produced, which differs from the clear coat 5 of Example 3 only by the type and amount of used Differentiate crosslinking agents. The composition these clearcoats 8 to 10 are summarized in Table 5. Application and curing as well as testing the resulting coating is carried out analogously to example 3. The test results of the clear lacquer coatings are in Table 6 that of the glass lifts shown in Table 7.  

Example 9 Production of a silyl and acetoacetate group Copolymer 6

According to the procedure described in Comparative Example 1 under 1.1 Manufacturing instructions given in Table 1 listed components and among those in Table 2 conditions listed a silyl and acetoacetate Copolymer 6 produced. As a solvent was a mixture of 50 parts of xylene and 50 parts of methoxypropyl acetate. As Azobis (isovaleronitrile) was used as the initiator.

Production of a clear lacquer 11

From 97.1 parts of the silyl and described above copolymer containing acetoacetate groups 6, 2.1 parts of a commercially available alkoxylated tetrafunctional Pentaerythritol acrylic acid ester with a double binding equivalent weight of 145 (commercial product "Monigomer PPTTA" from Hans Rahn & Co, Zurich), 2.2 parts butanol, 2.2 parts ethanol, 3.7 parts Butyl acetate, 0.70 parts of a solution of a commercially available Leveling agent (solution of 5 parts of a polyether-modified methylpolysiloxane in 1 part Butanol and 94 parts of xylene) and 1.8 parts of a solution another commercially available leveling agent (Solution of 1 part of a polysiloxane polyether copolymer in 79 parts Shellsol®A and 20 parts xylene) a clear coat 11 is produced by the individual Components are mixed in succession with a dissolver will.

1.00 part of a 20% strength catalyst is used Solution of diazabicycloundecen in ethanol, 7 parts  a 10% solution of dibutyltin dilaurate in Butanol, 7 parts of a 3% solution of γ-mercapto propyltrimethoxysilane in xylene and 0.75 parts 4,5-dihydro-1- [3- (triethoxysilyl) propyl] imidazole used. With a paint thinner consisting of 50% by weight of butyl acetate, 10% by weight of gasoline with a Boiling range from 135 to 180 ° C, 15 wt .-% xylene, 15% by weight of Naphta® solvent, 5% by weight of methoxypropylacetate and 5% by weight of butyl glycol acetate is added to a Viscosity of 18 s in a DIN 4 flow cup at 23 ° C set.

Application of the clear coat 11

The application and curing of the clear coat 11 (Dry film thickness 50-55 µm) analog to Comparative Example 1 on phosphated steel sheets (Bonder 132), previously with a conventional Epoxy filler (dry film thickness 50-55 µm) and the conventional basecoat described above (Dry film thickness approx. 12-15 µm) coated were. Checking the technical properties the coating and the glass lifts also took place analogous to comparative example 1. The results are summarized in Tables 3 and 4.  

Table 1

Monomer components of copolymers 1 to 6

Table 2

Polymerization conditions and key figures of copolymers 1 to 6

Table 3

Test results of the clear lacquer coatings of Examples 1, 2, 3 and 9 and of Comparative Examples 1 and 2

Table 4

Test results of the glass lifts of Examples 1, 2, 3 and 9 and Comparative Examples 1 and 2

Table 5

Composition of the clearcoats of Examples 3 to 8 (in parts by weight)

Table 6

Test results of the clear lacquer coatings of Examples 3 to 8

Table 7

Test results of the glass lifts of Examples 3 to 8

Claims (22)

1. Process for the preparation of a curable composition comprising a silyl group-containing polymeric compound, the silyl groups being formed by monomeric compounds of the general formula (I) With
R¹ = alkyl, aryl, acyl, aralkyl with 1 to 10 carbon atoms
R² = organic residue with polymerizable double bond or organic residue with reactive group
X = hydrolyzable group
n = 1, 2 or 3
be introduced into the polymer, characterized in that

• 1. at least one polymer A, the monomeric compounds of the formula (I) and monomeric compounds having at least one group with active hydrogen atoms of the type or contains -CH₂- copolymerized,
  or
• 2. a mixture of at least one polymer B, which contains copolymerized monomeric compounds of the formula (I), and at least one polymer C, which contains monomeric compounds having at least one group with active hydrogen atoms of the type or contains -CH₂- copolymerized,
• 3. at least one organic solvent,
• 4. if appropriate, at least one monomeric and / or oligomeric compound which has more than one group which is reactive toward active hydrogen atoms, as crosslinking agent,
• 5. If necessary, pigments and / or fillers and
• 6. If necessary, auxiliaries and additives

are mixed and optionally dispersed and that before Application a mixture of at least one catalyst for curing over the silyl groups and at least one catalyst for curing added the group with active hydrogen atoms becomes. 2. The method according to claim 1, characterized in that

• 1. 20 to 75 wt .-%, based on the total weight of the composition, of at least one polymer A or
• 2. 20 to 75% by weight, based on the total weight of the composition, of the mixture of at least one polymer B and at least one polymer C and
• 3. 0.5 to 5% by weight, based on the binder content of the composition, of the catalyst mixture

are used and that the crosslinking agent in such an amount is used that the equivalent ratio the reactive group of the crosslinking agent to the active hydrogen atoms of polymer A or C is between 0: 1 and 1.5: 1. 3. The method according to claim 1, characterized in that

• 1. 40 to 65 wt .-%, based on the total weight of the composition, of at least one polymer A or
• 2. 40 to 60% by weight, based on the total weight of the composition, of the mixture of at least one polymer B and at least one polymer C and
• 3. 1 to 3% by weight, based on the binder content of the composition, of the catalyst mixture

are used and that the crosslinking agent is used in such an amount that the Equivalent ratio of the reactive groups of the Crosslinking agent to the active hydrogen atoms of the polymer A or C between 0.5: 1 and 1: 1 lies. 4. The method according to any one of claims 1 to 3, characterized in that a polymer A is used, which is obtainable by copolymerization of

• a) 20 to 50 wt .-%, preferably 30 to 40 wt .-%, a mixture of at least one of the silane monomers (I) and at least one ethylenically unsaturated monomer with at least one group with active hydrogen atoms of the type or -CH₂-,
• b) 0 to 30% by weight, preferably 20 to 25% by weight, of at least one monomer with at least 2 polymerizable ethylenically unsaturated double bonds,
• c) 0 to 40% by weight, preferably 10 to 20% by weight, of at least one vinylaromatic hydrocarbon,
• d) 20 to 80% by weight, preferably 30 to 70% by weight, of at least one alkyl ester of acrylic and / or methacrylic acid and
• e) 0 to 20% by weight of ethylenically unsaturated monomers without groups with active hydrogen, the sum of the parts by weight of components a to e being 100% by weight in each case.

5. The method according to claim 4, characterized in that the mixing ratio of the silane monomers used as component a to the ethylenically unsaturated monomers having at least one group with active hydrogen atoms of the type or -CH₂- is between 10: 1 and 1:10. 6. The method according to claim 4, characterized in that the mixing ratio of the silane monomers used as component a to the ethylenically unsaturated monomers having at least one group with active hydrogen atoms of the type or -CH₂- is between 5: 1 and 1: 5. 7. The method according to claim 4, characterized in that the mixing ratio of the silane monomers used as component a to the ethylenically unsaturated monomers having at least one group with active hydrogen atoms of the type or -CH₂- is between 3: 1 and 1: 2. 8. The method according to any one of claims 1 to 3, characterized in that a polymer B is used, which is obtainable by copolymerization of

• f) 20 to 50% by weight, preferably 30 to 40% by weight, of a mixture of at least one of the silane monomers (I),
• g) 0 to 30% by weight, preferably 20 to 25% by weight, of at least one monomer with at least two polymerizable ethylenically unsaturated double bonds,
• h) 0 to 40% by weight, preferably 10 to 20% by weight, of at least one vinylaromatic hydrocarbon,
• i) 20 to 80% by weight, preferably 30 to 70% by weight, of at least one alkyl ester of acrylic and / or methacrylic acid and
• j) 0 to 20% by weight of ethylenically unsaturated monomers without groups with active hydrogen, the sum of the parts by weight of components f to j being 100% by weight in each case

and that a polymer C is used, which is obtainable by copolymerization of

• k) 20 to 50% by weight, preferably 30 to 40% by weight, of at least one ethylenically unsaturated monomer having at least one group with active hydrogen atoms of the type or -CH₂-,
• l) 0 to 30% by weight, preferably 20 to 25% by weight, of at least one monomer with at least 2 polymerizable ethylenically unsaturated double bonds,
• m) 0 to 40% by weight, preferably 10 to 20% by weight, of at least one vinylaromatic hydrocarbon,
• n) 20 to 80 wt .-%, preferably 30 to 70 wt .-%, at least one alkyl ester of acrylic and / or methacrylic acid and
• o) 0 to 20% by weight of ethylenically unsaturated monomers without groups with active hydrogen, the sum of the proportions by weight of components k to o being 100% by weight in each case.

9. The method according to claim 8, characterized in that the mixing ratio of the polymer B to the polymer C is between 10: 1 and 1:10. 10. The method according to claim 8, characterized in that the mixing ratio of the polymer B to the polymer C is between 5: 1 and 1: 5. 11. The method according to claim 8, characterized in that the mixing ratio of the polymer B to the polymer C is between 3: 1 and 1: 2. 12. The method according to any one of claims 1 to 11, characterized characterized in that as monomeric compounds with at least one group with active hydrogen atoms acetoacetate and / or methane tricarboxylic acid and / or those containing malonic acid groups Connections are used. 13. The method according to any one of claims 4 to 12, characterized characterized in that as a monomeric compound of the formula (I) γ-methacryloxypropyltrimethoxysilane is used. 14. The method according to any one of claims 4 to 13, characterized characterized in that as monomeric compounds with at least one group with active hydrogen atoms Acetoacetoxyethyl methacrylate used becomes.   15. The method according to any one of claims 1 to 14, characterized characterized in that as a crosslinking agent monomeric and / or oligomeric compounds with more than one ethylenically unsaturated double bond can be used per molecule. 16. Curable compositions, characterized in that that they are using a method according to one of the claims 1 to 15 can be produced. 17. Use of the curable composition according to claim 16 as a coating agent for the automotive or car refinishing. 18. Use of the curable composition according to claim 16 as top or clear coat.